Merge tag 'trace-v5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing updates from Steven Rostedt:

 - simplify the Kconfig use of FTRACE and TRACE_IRQFLAGS_SUPPORT

 - bootconfig can now start histograms

 - bootconfig supports group/all enabling

 - histograms now can put values in linear size buckets

 - execnames can be passed to synthetic events

 - introduce "event probes" that attach to other events and can retrieve
   data from pointers of fields, or record fields as different types (a
   pointer to a string as a string instead of just a hex number)

 - various fixes and clean ups

* tag 'trace-v5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (35 commits)
  tracing/doc: Fix table format in histogram code
  selftests/ftrace: Add selftest for testing duplicate eprobes and kprobes
  selftests/ftrace: Add selftest for testing eprobe events on synthetic events
  selftests/ftrace: Add test case to test adding and removing of event probe
  selftests/ftrace: Fix requirement check of README file
  selftests/ftrace: Add clear_dynamic_events() to test cases
  tracing: Add a probe that attaches to trace events
  tracing/probes: Reject events which have the same name of existing one
  tracing/probes: Have process_fetch_insn() take a void * instead of pt_regs
  tracing/probe: Change traceprobe_set_print_fmt() to take a type
  tracing/probes: Use struct_size() instead of defining custom macros
  tracing/probes: Allow for dot delimiter as well as slash for system names
  tracing/probe: Have traceprobe_parse_probe_arg() take a const arg
  tracing: Have dynamic events have a ref counter
  tracing: Add DYNAMIC flag for dynamic events
  tracing: Replace deprecated CPU-hotplug functions.
  MAINTAINERS: Add an entry for os noise/latency
  tracepoint: Fix kerneldoc comments
  bootconfig/tracing/ktest: Update ktest example for boot-time tracing
  tools/bootconfig: Use per-group/all enable option in ftrace2bconf script
  ...

63 files changed, 2149 insertions, 275 deletions

diff --git a/Documentation/trace/boottime-trace.rst b/Documentation/trace/boottime-trace.rst
index 8053898cfeb4..6dcfbc64014d 100644
--- a/Documentation/trace/boottime-trace.rst
+++ b/Documentation/trace/boottime-trace.rst
@@ -125,6 +125,71 @@ Note that kprobe and synthetic event definitions can be written under
 instance node, but those are also visible from other instances. So please
 take care for event name conflict.
 
+Ftrace Histogram Options
+------------------------
+
+Since it is too long to write a histogram action as a string for per-event
+action option, there are tree-style options under per-event 'hist' subkey
+for the histogram actions. For the detail of the each parameter,
+please read the event histogram document [3]_.
+
+.. [3] See :ref:`Documentation/trace/histogram.rst <histogram>`
+
+ftrace.[instance.INSTANCE.]event.GROUP.EVENT.hist.[N.]keys = KEY1[, KEY2[...]]
+  Set histogram key parameters. (Mandatory)
+  The 'N' is a digit string for the multiple histogram. You can omit it
+  if there is one histogram on the event.
+
+ftrace.[instance.INSTANCE.]event.GROUP.EVENT.hist.[N.]values = VAL1[, VAL2[...]]
+  Set histogram value parameters.
+
+ftrace.[instance.INSTANCE.]event.GROUP.EVENT.hist.[N.]sort = SORT1[, SORT2[...]]
+  Set histogram sort parameter options.
+
+ftrace.[instance.INSTANCE.]event.GROUP.EVENT.hist.[N.]size = NR_ENTRIES
+  Set histogram size (number of entries).
+
+ftrace.[instance.INSTANCE.]event.GROUP.EVENT.hist.[N.]name = NAME
+  Set histogram name.
+
+ftrace.[instance.INSTANCE.]event.GROUP.EVENT.hist.[N.]var.VARIABLE = EXPR
+  Define a new VARIABLE by EXPR expression.
+
+ftrace.[instance.INSTANCE.]event.GROUP.EVENT.hist.[N.]<pause|continue|clear>
+  Set histogram control parameter. You can set one of them.
+
+ftrace.[instance.INSTANCE.]event.GROUP.EVENT.hist.[N.]onmatch.[M.]event = GROUP.EVENT
+  Set histogram 'onmatch' handler matching event parameter.
+  The 'M' is a digit string for the multiple 'onmatch' handler. You can omit it
+  if there is one 'onmatch' handler on this histogram.
+
+ftrace.[instance.INSTANCE.]event.GROUP.EVENT.hist.[N.]onmatch.[M.]trace = EVENT[, ARG1[...]]
+  Set histogram 'trace' action for 'onmatch'.
+  EVENT must be a synthetic event name, and ARG1... are parameters
+  for that event. Mandatory if 'onmatch.event' option is set.
+
+ftrace.[instance.INSTANCE.]event.GROUP.EVENT.hist.[N.]onmax.[M.]var = VAR
+  Set histogram 'onmax' handler variable parameter.
+
+ftrace.[instance.INSTANCE.]event.GROUP.EVENT.hist.[N.]onchange.[M.]var = VAR
+  Set histogram 'onchange' handler variable parameter.
+
+ftrace.[instance.INSTANCE.]event.GROUP.EVENT.hist.[N.]<onmax|onchange>.[M.]save = ARG1[, ARG2[...]]
+  Set histogram 'save' action parameters for 'onmax' or 'onchange' handler.
+  This option or below 'snapshot' option is mandatory if 'onmax.var' or
+  'onchange.var' option is set.
+
+ftrace.[instance.INSTANCE.]event.GROUP.EVENT.hist.[N.]<onmax|onchange>.[M.]snapshot
+  Set histogram 'snapshot' action for 'onmax' or 'onchange' handler.
+  This option or above 'save' option is mandatory if 'onmax.var' or
+  'onchange.var' option is set.
+
+ftrace.[instance.INSTANCE.]event.GROUP.EVENT.hist.filter = FILTER_EXPR
+  Set histogram filter expression. You don't need 'if' in the FILTER_EXPR.
+
+Note that this 'hist' option can conflict with the per-event 'actions'
+option if the 'actions' option has a histogram action.
+
 
 When to Start
 =============
@@ -159,13 +224,23 @@ below::
         }
         synthetic.initcall_latency {
                 fields = "unsigned long func", "u64 lat"
-                actions = "hist:keys=func.sym,lat:vals=lat:sort=lat"
+                hist {
+                        keys = func.sym, lat
+                        values = lat
+                        sort = lat
+                }
         }
-        initcall.initcall_start {
-                actions = "hist:keys=func:ts0=common_timestamp.usecs"
+        initcall.initcall_start.hist {
+                keys = func
+                var.ts0 = common_timestamp.usecs
         }
-        initcall.initcall_finish {
-                actions = "hist:keys=func:lat=common_timestamp.usecs-$ts0:onmatch(initcall.initcall_start).initcall_latency(func,$lat)"
+        initcall.initcall_finish.hist {
+                keys = func
+                var.lat = common_timestamp.usecs - $ts0
+                onmatch {
+                        event = initcall.initcall_start
+                        trace = initcall_latency, func, $lat
+                }
         }
   }
 
diff --git a/Documentation/trace/histogram.rst b/Documentation/trace/histogram.rst
index f99be8062bc8..533415644c54 100644
--- a/Documentation/trace/histogram.rst
+++ b/Documentation/trace/histogram.rst
@@ -70,15 +70,16 @@ Documentation written by Tom Zanussi
   modified by appending any of the following modifiers to the field
   name:
 
-	=========== ==========================================
-        .hex        display a number as a hex value
-	.sym        display an address as a symbol
-	.sym-offset display an address as a symbol and offset
-	.syscall    display a syscall id as a system call name
-	.execname   display a common_pid as a program name
-	.log2       display log2 value rather than raw number
-	.usecs      display a common_timestamp in microseconds
-	=========== ==========================================
+	=============  =================================================
+        .hex           display a number as a hex value
+	.sym           display an address as a symbol
+	.sym-offset    display an address as a symbol and offset
+	.syscall       display a syscall id as a system call name
+	.execname      display a common_pid as a program name
+	.log2          display log2 value rather than raw number
+	.buckets=size  display grouping of values rather than raw number
+	.usecs         display a common_timestamp in microseconds
+	=============  =================================================
 
   Note that in general the semantics of a given field aren't
   interpreted when applying a modifier to it, but there are some
@@ -228,7 +229,7 @@ Extended error information
   that lists the total number of bytes requested for each function in
   the kernel that made one or more calls to kmalloc::
 
-    # echo 'hist:key=call_site:val=bytes_req' > \
+    # echo 'hist:key=call_site:val=bytes_req.buckets=32' > \
             /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger
 
   This tells the tracing system to create a 'hist' trigger using the
@@ -1823,20 +1824,99 @@ and variables defined on other events (see Section 2.2.3 below on
 how that is done using hist trigger 'onmatch' action). Once that is
 done, the 'wakeup_latency' synthetic event instance is created.
 
-A histogram can now be defined for the new synthetic event::
-
-  # echo 'hist:keys=pid,prio,lat.log2:sort=pid,lat' >> \
-        /sys/kernel/debug/tracing/events/synthetic/wakeup_latency/trigger
-
 The new event is created under the tracing/events/synthetic/ directory
 and looks and behaves just like any other event::
 
   # ls /sys/kernel/debug/tracing/events/synthetic/wakeup_latency
         enable  filter  format  hist  id  trigger
 
+A histogram can now be defined for the new synthetic event::
+
+  # echo 'hist:keys=pid,prio,lat.log2:sort=lat' >> \
+        /sys/kernel/debug/tracing/events/synthetic/wakeup_latency/trigger
+
+The above shows the latency "lat" in a power of 2 grouping.
+
 Like any other event, once a histogram is enabled for the event, the
 output can be displayed by reading the event's 'hist' file.
 
+  # cat /sys/kernel/debug/tracing/events/synthetic/wakeup_latency/hist
+
+  # event histogram
+  #
+  # trigger info: hist:keys=pid,prio,lat.log2:vals=hitcount:sort=lat.log2:size=2048 [active]
+  #
+
+  { pid:       2035, prio:          9, lat: ~ 2^2  } hitcount:         43
+  { pid:       2034, prio:          9, lat: ~ 2^2  } hitcount:         60
+  { pid:       2029, prio:          9, lat: ~ 2^2  } hitcount:        965
+  { pid:       2034, prio:        120, lat: ~ 2^2  } hitcount:          9
+  { pid:       2033, prio:        120, lat: ~ 2^2  } hitcount:          5
+  { pid:       2030, prio:          9, lat: ~ 2^2  } hitcount:        335
+  { pid:       2030, prio:        120, lat: ~ 2^2  } hitcount:         10
+  { pid:       2032, prio:        120, lat: ~ 2^2  } hitcount:          1
+  { pid:       2035, prio:        120, lat: ~ 2^2  } hitcount:          2
+  { pid:       2031, prio:          9, lat: ~ 2^2  } hitcount:        176
+  { pid:       2028, prio:        120, lat: ~ 2^2  } hitcount:         15
+  { pid:       2033, prio:          9, lat: ~ 2^2  } hitcount:         91
+  { pid:       2032, prio:          9, lat: ~ 2^2  } hitcount:        125
+  { pid:       2029, prio:        120, lat: ~ 2^2  } hitcount:          4
+  { pid:       2031, prio:        120, lat: ~ 2^2  } hitcount:          3
+  { pid:       2029, prio:        120, lat: ~ 2^3  } hitcount:          2
+  { pid:       2035, prio:          9, lat: ~ 2^3  } hitcount:         41
+  { pid:       2030, prio:        120, lat: ~ 2^3  } hitcount:          1
+  { pid:       2032, prio:          9, lat: ~ 2^3  } hitcount:         32
+  { pid:       2031, prio:          9, lat: ~ 2^3  } hitcount:         44
+  { pid:       2034, prio:          9, lat: ~ 2^3  } hitcount:         40
+  { pid:       2030, prio:          9, lat: ~ 2^3  } hitcount:         29
+  { pid:       2033, prio:          9, lat: ~ 2^3  } hitcount:         31
+  { pid:       2029, prio:          9, lat: ~ 2^3  } hitcount:         31
+  { pid:       2028, prio:        120, lat: ~ 2^3  } hitcount:         18
+  { pid:       2031, prio:        120, lat: ~ 2^3  } hitcount:          2
+  { pid:       2028, prio:        120, lat: ~ 2^4  } hitcount:          1
+  { pid:       2029, prio:          9, lat: ~ 2^4  } hitcount:          4
+  { pid:       2031, prio:        120, lat: ~ 2^7  } hitcount:          1
+  { pid:       2032, prio:        120, lat: ~ 2^7  } hitcount:          1
+
+  Totals:
+      Hits: 2122
+      Entries: 30
+      Dropped: 0
+
+
+The latency values can also be grouped linearly by a given size with
+the ".buckets" modifier and specify a size (in this case groups of 10).
+
+  # echo 'hist:keys=pid,prio,lat.buckets=10:sort=lat' >> \
+        /sys/kernel/debug/tracing/events/synthetic/wakeup_latency/trigger
+
+  # event histogram
+  #
+  # trigger info: hist:keys=pid,prio,lat.buckets=10:vals=hitcount:sort=lat.buckets=10:size=2048 [active]
+  #
+
+  { pid:       2067, prio:          9, lat: ~ 0-9 } hitcount:        220
+  { pid:       2068, prio:          9, lat: ~ 0-9 } hitcount:        157
+  { pid:       2070, prio:          9, lat: ~ 0-9 } hitcount:        100
+  { pid:       2067, prio:        120, lat: ~ 0-9 } hitcount:          6
+  { pid:       2065, prio:        120, lat: ~ 0-9 } hitcount:          2
+  { pid:       2066, prio:        120, lat: ~ 0-9 } hitcount:          2
+  { pid:       2069, prio:          9, lat: ~ 0-9 } hitcount:        122
+  { pid:       2069, prio:        120, lat: ~ 0-9 } hitcount:          8
+  { pid:       2070, prio:        120, lat: ~ 0-9 } hitcount:          1
+  { pid:       2068, prio:        120, lat: ~ 0-9 } hitcount:          7
+  { pid:       2066, prio:          9, lat: ~ 0-9 } hitcount:        365
+  { pid:       2064, prio:        120, lat: ~ 0-9 } hitcount:         35
+  { pid:       2065, prio:          9, lat: ~ 0-9 } hitcount:        998
+  { pid:       2071, prio:          9, lat: ~ 0-9 } hitcount:         85
+  { pid:       2065, prio:          9, lat: ~ 10-19 } hitcount:          2
+  { pid:       2064, prio:        120, lat: ~ 10-19 } hitcount:          2
+
+  Totals:
+      Hits: 2112
+      Entries: 16
+      Dropped: 0
+
 2.2.3 Hist trigger 'handlers' and 'actions'
 -------------------------------------------
 
diff --git a/MAINTAINERS b/MAINTAINERS
index cfec5dc5a76f..4278b389218e 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -18973,6 +18973,20 @@ F:	arch/x86/mm/testmmiotrace.c
 F:	include/linux/mmiotrace.h
 F:	kernel/trace/trace_mmiotrace.c
 
+TRACING OS NOISE / LATENCY TRACERS
+M:	Steven Rostedt <rostedt@goodmis.org>
+M:	Daniel Bristot de Oliveira <bristot@kernel.org>
+S:	Maintained
+F:	kernel/trace/trace_osnoise.c
+F:	include/trace/events/osnoise.h
+F:	kernel/trace/trace_hwlat.c
+F:	kernel/trace/trace_irqsoff.c
+F:	kernel/trace/trace_sched_wakeup.c
+F:	Documentation/trace/osnoise-tracer.rst
+F:	Documentation/trace/timerlat-tracer.rst
+F:	Documentation/trace/hwlat_detector.rst
+F:	arch/*/kernel/trace.c
+
 TRADITIONAL CHINESE DOCUMENTATION
 M:	Hu Haowen <src.res@email.cn>
 L:	linux-doc-tw-discuss@lists.sourceforge.net
diff --git a/arch/Kconfig b/arch/Kconfig
index 98db63496bab..3743174da870 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -197,6 +197,9 @@ config HAVE_FUNCTION_ERROR_INJECTION
 config HAVE_NMI
 	bool
 
+config TRACE_IRQFLAGS_SUPPORT
+	bool
+
 #
 # An arch should select this if it provides all these things:
 #
diff --git a/arch/arc/Kconfig b/arch/arc/Kconfig
index f631a7a60979..3a5a80f302e1 100644
--- a/arch/arc/Kconfig
+++ b/arch/arc/Kconfig
@@ -49,9 +49,7 @@ config ARC
 	select PERF_USE_VMALLOC if ARC_CACHE_VIPT_ALIASING
 	select HAVE_ARCH_JUMP_LABEL if ISA_ARCV2 && !CPU_ENDIAN_BE32
 	select SET_FS
-
-config TRACE_IRQFLAGS_SUPPORT
-	def_bool y
+	select TRACE_IRQFLAGS_SUPPORT
 
 config LOCKDEP_SUPPORT
 	def_bool y
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index f1d6531b5ce5..99863022436d 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -126,6 +126,7 @@ config ARM
 	select RTC_LIB
 	select SET_FS
 	select SYS_SUPPORTS_APM_EMULATION
+	select TRACE_IRQFLAGS_SUPPORT if !CPU_V7M
 	# Above selects are sorted alphabetically; please add new ones
 	# according to that.  Thanks.
 	help
@@ -189,10 +190,6 @@ config LOCKDEP_SUPPORT
 	bool
 	default y
 
-config TRACE_IRQFLAGS_SUPPORT
-	bool
-	default !CPU_V7M
-
 config ARCH_HAS_ILOG2_U32
 	bool
 
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 9dc1720a909f..077f2ec4eeb2 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -220,6 +220,7 @@ config ARM64
 	select SYSCTL_EXCEPTION_TRACE
 	select THREAD_INFO_IN_TASK
 	select HAVE_ARCH_USERFAULTFD_MINOR if USERFAULTFD
+	select TRACE_IRQFLAGS_SUPPORT
 	help
 	  ARM 64-bit (AArch64) Linux support.
 
@@ -287,9 +288,6 @@ config ILLEGAL_POINTER_VALUE
 config LOCKDEP_SUPPORT
 	def_bool y
 
-config TRACE_IRQFLAGS_SUPPORT
-	def_bool y
-
 config GENERIC_BUG
 	def_bool y
 	depends on BUG
diff --git a/arch/csky/Kconfig b/arch/csky/Kconfig
index 2716f6395ba7..9d4d898df76b 100644
--- a/arch/csky/Kconfig
+++ b/arch/csky/Kconfig
@@ -82,6 +82,7 @@ config CSKY
 	select PCI_SYSCALL if PCI
 	select PCI_MSI if PCI
 	select SET_FS
+	select TRACE_IRQFLAGS_SUPPORT
 
 config LOCKDEP_SUPPORT
 	def_bool y
@@ -139,9 +140,6 @@ config STACKTRACE_SUPPORT
 config TIME_LOW_RES
 	def_bool y
 
-config TRACE_IRQFLAGS_SUPPORT
-	def_bool y
-
 config CPU_TLB_SIZE
 	int
 	default "128"	if (CPU_CK610 || CPU_CK807 || CPU_CK810)
diff --git a/arch/hexagon/Kconfig b/arch/hexagon/Kconfig
index aab1a40eb653..15dd8f38b698 100644
--- a/arch/hexagon/Kconfig
+++ b/arch/hexagon/Kconfig
@@ -32,6 +32,7 @@ config HEXAGON
 	select GENERIC_CPU_DEVICES
 	select SET_FS
 	select ARCH_WANT_LD_ORPHAN_WARN
+	select TRACE_IRQFLAGS_SUPPORT
 	help
 	  Qualcomm Hexagon is a processor architecture designed for high
 	  performance and low power across a wide variety of applications.
@@ -53,9 +54,6 @@ config EARLY_PRINTK
 config MMU
 	def_bool y
 
-config TRACE_IRQFLAGS_SUPPORT
-	def_bool y
-
 config GENERIC_CSUM
 	def_bool y
 
diff --git a/arch/microblaze/Kconfig b/arch/microblaze/Kconfig
index 14a67a42fcae..59798e43cdb0 100644
--- a/arch/microblaze/Kconfig
+++ b/arch/microblaze/Kconfig
@@ -44,6 +44,7 @@ config MICROBLAZE
 	select SPARSE_IRQ
 	select SET_FS
 	select ZONE_DMA
+	select TRACE_IRQFLAGS_SUPPORT
 
 # Endianness selection
 choice
diff --git a/arch/microblaze/Kconfig.debug b/arch/microblaze/Kconfig.debug
index 865527ac332a..a4e40e534e6a 100644
--- a/arch/microblaze/Kconfig.debug
+++ b/arch/microblaze/Kconfig.debug
@@ -1,6 +1 @@
 # SPDX-License-Identifier: GPL-2.0-only
-# For a description of the syntax of this configuration file,
-# see Documentation/kbuild/kconfig-language.rst.
-
-config TRACE_IRQFLAGS_SUPPORT
-	def_bool y
diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index 9b8ff6c2c1e3..771ca53af06d 100644
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -98,6 +98,7 @@ config MIPS
 	select PCI_MSI_ARCH_FALLBACKS if PCI_MSI
 	select RTC_LIB
 	select SYSCTL_EXCEPTION_TRACE
+	select TRACE_IRQFLAGS_SUPPORT
 	select VIRT_TO_BUS
 	select ARCH_HAS_ELFCORE_COMPAT
 
diff --git a/arch/mips/Kconfig.debug b/arch/mips/Kconfig.debug
index 43dbf5930796..f4ae7900fcd3 100644
--- a/arch/mips/Kconfig.debug
+++ b/arch/mips/Kconfig.debug
@@ -1,9 +1,5 @@
 # SPDX-License-Identifier: GPL-2.0
 
-config TRACE_IRQFLAGS_SUPPORT
-	bool
-	default y
-
 config EARLY_PRINTK
 	bool "Early printk" if EXPERT
 	depends on SYS_HAS_EARLY_PRINTK
diff --git a/arch/nds32/Kconfig b/arch/nds32/Kconfig
index 9c9f3877abf9..aea26e739543 100644
--- a/arch/nds32/Kconfig
+++ b/arch/nds32/Kconfig
@@ -46,6 +46,7 @@ config NDS32
 	select HAVE_FTRACE_MCOUNT_RECORD
 	select HAVE_DYNAMIC_FTRACE
 	select SET_FS
+	select TRACE_IRQFLAGS_SUPPORT
 	help
 	  Andes(nds32) Linux support.
 
@@ -62,9 +63,6 @@ config GENERIC_LOCKBREAK
 	def_bool y
 	depends on PREEMPTION
 
-config TRACE_IRQFLAGS_SUPPORT
-	def_bool y
-
 config STACKTRACE_SUPPORT
 	def_bool y
 
diff --git a/arch/nios2/Kconfig b/arch/nios2/Kconfig
index 3efe5533ea1c..33fd06f5fa41 100644
--- a/arch/nios2/Kconfig
+++ b/arch/nios2/Kconfig
@@ -41,9 +41,6 @@ config NO_IOPORT_MAP
 config FPU
 	def_bool n
 
-config TRACE_IRQFLAGS_SUPPORT
-	def_bool n
-
 menu "Kernel features"
 
 source "kernel/Kconfig.hz"
diff --git a/arch/openrisc/Kconfig b/arch/openrisc/Kconfig
index 50035a9816c8..e804026b4797 100644
--- a/arch/openrisc/Kconfig
+++ b/arch/openrisc/Kconfig
@@ -37,6 +37,7 @@ config OPENRISC
 	select GENERIC_IRQ_MULTI_HANDLER
 	select MMU_GATHER_NO_RANGE if MMU
 	select SET_FS
+	select TRACE_IRQFLAGS_SUPPORT
 
 config CPU_BIG_ENDIAN
 	def_bool y
@@ -50,9 +51,6 @@ config GENERIC_HWEIGHT
 config NO_IOPORT_MAP
 	def_bool y
 
-config TRACE_IRQFLAGS_SUPPORT
-	def_bool y
-
 # For now, use generic checksum functions
 #These can be reimplemented in assembly later if so inclined
 config GENERIC_CSUM
diff --git a/arch/parisc/Kconfig b/arch/parisc/Kconfig
index 95d4bbf4e455..3001a7d8fc76 100644
--- a/arch/parisc/Kconfig
+++ b/arch/parisc/Kconfig
@@ -66,6 +66,7 @@ config PARISC
 	select HAVE_DYNAMIC_FTRACE_WITH_REGS
 	select HAVE_SOFTIRQ_ON_OWN_STACK if IRQSTACKS
 	select SET_FS
+	select TRACE_IRQFLAGS_SUPPORT
 
 	help
 	  The PA-RISC microprocessor is designed by Hewlett-Packard and used
diff --git a/arch/parisc/Kconfig.debug b/arch/parisc/Kconfig.debug
index 1478ded0e247..f66554cd5c45 100644
--- a/arch/parisc/Kconfig.debug
+++ b/arch/parisc/Kconfig.debug
@@ -1,4 +1 @@
 # SPDX-License-Identifier: GPL-2.0
-
-config TRACE_IRQFLAGS_SUPPORT
-	def_bool y
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 8a93b509337d..ba5b66189358 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -94,10 +94,6 @@ config STACKTRACE_SUPPORT
 	bool
 	default y
 
-config TRACE_IRQFLAGS_SUPPORT
-	bool
-	default y
-
 config LOCKDEP_SUPPORT
 	bool
 	default y
@@ -270,6 +266,7 @@ config PPC
 	select STRICT_KERNEL_RWX if STRICT_MODULE_RWX
 	select SYSCTL_EXCEPTION_TRACE
 	select THREAD_INFO_IN_TASK
+	select TRACE_IRQFLAGS_SUPPORT
 	select VIRT_TO_BUS			if !PPC64
 	#
 	# Please keep this list sorted alphabetically.
diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
index baf60fc350a4..aac669a6c3d8 100644
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig
@@ -113,6 +113,7 @@ config RISCV
 	select SPARSE_IRQ
 	select SYSCTL_EXCEPTION_TRACE
 	select THREAD_INFO_IN_TASK
+	select TRACE_IRQFLAGS_SUPPORT
 	select UACCESS_MEMCPY if !MMU
 	select ZONE_DMA32 if 64BIT
 
@@ -182,9 +183,6 @@ config ARCH_SUPPORTS_UPROBES
 config STACKTRACE_SUPPORT
 	def_bool y
 
-config TRACE_IRQFLAGS_SUPPORT
-	def_bool y
-
 config GENERIC_BUG
 	def_bool y
 	depends on BUG
diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index 92c0a1b4c528..5af51ace0588 100644
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -209,6 +209,7 @@ config S390
 	select SWIOTLB
 	select SYSCTL_EXCEPTION_TRACE
 	select THREAD_INFO_IN_TASK
+	select TRACE_IRQFLAGS_SUPPORT
 	select TTY
 	select VIRT_CPU_ACCOUNTING
 	select ZONE_DMA
diff --git a/arch/s390/Kconfig.debug b/arch/s390/Kconfig.debug
index 9ea6e61d5858..e94a2a7f6bf4 100644
--- a/arch/s390/Kconfig.debug
+++ b/arch/s390/Kconfig.debug
@@ -1,8 +1,5 @@
 # SPDX-License-Identifier: GPL-2.0
 
-config TRACE_IRQFLAGS_SUPPORT
-	def_bool y
-
 config EARLY_PRINTK
 	def_bool y
 
diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig
index f37280e805ea..6904f4bdbf00 100644
--- a/arch/sh/Kconfig
+++ b/arch/sh/Kconfig
@@ -69,6 +69,7 @@ config SUPERH
 	select RTC_LIB
 	select SET_FS
 	select SPARSE_IRQ
+	select TRACE_IRQFLAGS_SUPPORT
 	help
 	  The SuperH is a RISC processor targeted for use in embedded systems
 	  and consumer electronics; it was also used in the Sega Dreamcast
diff --git a/arch/sh/Kconfig.debug b/arch/sh/Kconfig.debug
index 28a43d63bde1..958f790273ab 100644
--- a/arch/sh/Kconfig.debug
+++ b/arch/sh/Kconfig.debug
@@ -1,8 +1,5 @@
 # SPDX-License-Identifier: GPL-2.0
 
-config TRACE_IRQFLAGS_SUPPORT
-	def_bool y
-
 config SH_STANDARD_BIOS
 	bool "Use LinuxSH standard BIOS"
 	help
diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig
index fa650e4eadba..b120ed947f50 100644
--- a/arch/sparc/Kconfig
+++ b/arch/sparc/Kconfig
@@ -47,6 +47,7 @@ config SPARC
 	select NEED_DMA_MAP_STATE
 	select NEED_SG_DMA_LENGTH
 	select SET_FS
+	select TRACE_IRQFLAGS_SUPPORT
 
 config SPARC32
 	def_bool !64BIT
diff --git a/arch/sparc/Kconfig.debug b/arch/sparc/Kconfig.debug
index 50a918d496c8..6b2bec1888b3 100644
--- a/arch/sparc/Kconfig.debug
+++ b/arch/sparc/Kconfig.debug
@@ -1,9 +1,5 @@
 # SPDX-License-Identifier: GPL-2.0
 
-config TRACE_IRQFLAGS_SUPPORT
-	bool
-	default y
-
 config DEBUG_DCFLUSH
 	bool "D-cache flush debugging"
 	depends on SPARC64 && DEBUG_KERNEL
diff --git a/arch/um/Kconfig b/arch/um/Kconfig
index 77e66d3719f6..8de2646fbdb1 100644
--- a/arch/um/Kconfig
+++ b/arch/um/Kconfig
@@ -22,6 +22,7 @@ config UML
 	select GENERIC_CPU_DEVICES
 	select HAVE_GCC_PLUGINS
 	select SET_FS
+	select TRACE_IRQFLAGS_SUPPORT
 	select TTY # Needed for line.c
 
 config MMU
@@ -52,10 +53,6 @@ config ISA
 config SBUS
 	bool
 
-config TRACE_IRQFLAGS_SUPPORT
-	bool
-	default y
-
 config LOCKDEP_SUPPORT
 	bool
 	default y
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 1146b85d708b..4e001bbbb425 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -259,6 +259,7 @@ config X86
 	select STACK_VALIDATION			if HAVE_STACK_VALIDATION && (HAVE_STATIC_CALL_INLINE || RETPOLINE)
 	select SYSCTL_EXCEPTION_TRACE
 	select THREAD_INFO_IN_TASK
+	select TRACE_IRQFLAGS_SUPPORT
 	select USER_STACKTRACE_SUPPORT
 	select VIRT_TO_BUS
 	select HAVE_ARCH_KCSAN			if X86_64
diff --git a/arch/x86/Kconfig.debug b/arch/x86/Kconfig.debug
index 80b57e7f4947..d3a6f74a94bd 100644
--- a/arch/x86/Kconfig.debug
+++ b/arch/x86/Kconfig.debug
@@ -1,8 +1,5 @@
 # SPDX-License-Identifier: GPL-2.0
 
-config TRACE_IRQFLAGS_SUPPORT
-	def_bool y
-
 config TRACE_IRQFLAGS_NMI_SUPPORT
 	def_bool y
 
diff --git a/arch/xtensa/Kconfig b/arch/xtensa/Kconfig
index 9bf2a9bc8539..0e56bad058fa 100644
--- a/arch/xtensa/Kconfig
+++ b/arch/xtensa/Kconfig
@@ -42,6 +42,7 @@ config XTENSA
 	select MODULES_USE_ELF_RELA
 	select PERF_USE_VMALLOC
 	select SET_FS
+	select TRACE_IRQFLAGS_SUPPORT
 	select VIRT_TO_BUS
 	help
 	  Xtensa processors are 32-bit RISC machines designed by Tensilica
@@ -73,9 +74,6 @@ config LOCKDEP_SUPPORT
 config STACKTRACE_SUPPORT
 	def_bool y
 
-config TRACE_IRQFLAGS_SUPPORT
-	def_bool y
-
 config MMU
 	def_bool n
 
diff --git a/include/linux/trace_events.h b/include/linux/trace_events.h
index 8e0631a4b046..3e475eeb5a99 100644
--- a/include/linux/trace_events.h
+++ b/include/linux/trace_events.h
@@ -310,8 +310,10 @@ enum {
 	TRACE_EVENT_FL_NO_SET_FILTER_BIT,
 	TRACE_EVENT_FL_IGNORE_ENABLE_BIT,
 	TRACE_EVENT_FL_TRACEPOINT_BIT,
+	TRACE_EVENT_FL_DYNAMIC_BIT,
 	TRACE_EVENT_FL_KPROBE_BIT,
 	TRACE_EVENT_FL_UPROBE_BIT,
+	TRACE_EVENT_FL_EPROBE_BIT,
 };
 
 /*
@@ -321,8 +323,10 @@ enum {
  *  NO_SET_FILTER - Set when filter has error and is to be ignored
  *  IGNORE_ENABLE - For trace internal events, do not enable with debugfs file
  *  TRACEPOINT    - Event is a tracepoint
+ *  DYNAMIC       - Event is a dynamic event (created at run time)
  *  KPROBE        - Event is a kprobe
  *  UPROBE        - Event is a uprobe
+ *  EPROBE        - Event is an event probe
  */
 enum {
 	TRACE_EVENT_FL_FILTERED		= (1 << TRACE_EVENT_FL_FILTERED_BIT),
@@ -330,8 +334,10 @@ enum {
 	TRACE_EVENT_FL_NO_SET_FILTER	= (1 << TRACE_EVENT_FL_NO_SET_FILTER_BIT),
 	TRACE_EVENT_FL_IGNORE_ENABLE	= (1 << TRACE_EVENT_FL_IGNORE_ENABLE_BIT),
 	TRACE_EVENT_FL_TRACEPOINT	= (1 << TRACE_EVENT_FL_TRACEPOINT_BIT),
+	TRACE_EVENT_FL_DYNAMIC		= (1 << TRACE_EVENT_FL_DYNAMIC_BIT),
 	TRACE_EVENT_FL_KPROBE		= (1 << TRACE_EVENT_FL_KPROBE_BIT),
 	TRACE_EVENT_FL_UPROBE		= (1 << TRACE_EVENT_FL_UPROBE_BIT),
+	TRACE_EVENT_FL_EPROBE		= (1 << TRACE_EVENT_FL_EPROBE_BIT),
 };
 
 #define TRACE_EVENT_FL_UKPROBE (TRACE_EVENT_FL_KPROBE | TRACE_EVENT_FL_UPROBE)
@@ -347,7 +353,14 @@ struct trace_event_call {
 	struct trace_event	event;
 	char			*print_fmt;
 	struct event_filter	*filter;
-	void			*mod;
+	/*
+	 * Static events can disappear with modules,
+	 * where as dynamic ones need their own ref count.
+	 */
+	union {
+		void				*module;
+		atomic_t			refcnt;
+	};
 	void			*data;
 
 	/* See the TRACE_EVENT_FL_* flags above */
@@ -363,6 +376,42 @@ struct trace_event_call {
 #endif
 };
 
+#ifdef CONFIG_DYNAMIC_EVENTS
+bool trace_event_dyn_try_get_ref(struct trace_event_call *call);
+void trace_event_dyn_put_ref(struct trace_event_call *call);
+bool trace_event_dyn_busy(struct trace_event_call *call);
+#else
+static inline bool trace_event_dyn_try_get_ref(struct trace_event_call *call)
+{
+	/* Without DYNAMIC_EVENTS configured, nothing should be calling this */
+	return false;
+}
+static inline void trace_event_dyn_put_ref(struct trace_event_call *call)
+{
+}
+static inline bool trace_event_dyn_busy(struct trace_event_call *call)
+{
+	/* Nothing should call this without DYNAIMIC_EVENTS configured. */
+	return true;
+}
+#endif
+
+static inline bool trace_event_try_get_ref(struct trace_event_call *call)
+{
+	if (call->flags & TRACE_EVENT_FL_DYNAMIC)
+		return trace_event_dyn_try_get_ref(call);
+	else
+		return try_module_get(call->module);
+}
+
+static inline void trace_event_put_ref(struct trace_event_call *call)
+{
+	if (call->flags & TRACE_EVENT_FL_DYNAMIC)
+		trace_event_dyn_put_ref(call);
+	else
+		module_put(call->module);
+}
+
 #ifdef CONFIG_PERF_EVENTS
 static inline bool bpf_prog_array_valid(struct trace_event_call *call)
 {
@@ -634,6 +683,7 @@ enum event_trigger_type {
 	ETT_EVENT_ENABLE	= (1 << 3),
 	ETT_EVENT_HIST		= (1 << 4),
 	ETT_HIST_ENABLE		= (1 << 5),
+	ETT_EVENT_EPROBE	= (1 << 6),
 };
 
 extern int filter_match_preds(struct event_filter *filter, void *rec);
diff --git a/include/linux/tracepoint.h b/include/linux/tracepoint.h
index ab58696d0ddd..28031b15f878 100644
--- a/include/linux/tracepoint.h
+++ b/include/linux/tracepoint.h
@@ -475,7 +475,7 @@ static inline struct tracepoint *tracepoint_ptr_deref(tracepoint_ptr_t *p)
  *	*
  *	* The declared 'local variable' is called '__entry'
  *	*
- *	* __field(pid_t, prev_prid) is equivalent to a standard declaration:
+ *	* __field(pid_t, prev_pid) is equivalent to a standard declaration:
  *	*
  *	*	pid_t	prev_pid;
  *	*
diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig
index 3ee23f4d437f..420ff4bc67fd 100644
--- a/kernel/trace/Kconfig
+++ b/kernel/trace/Kconfig
@@ -135,10 +135,9 @@ config TRACING_SUPPORT
 	depends on STACKTRACE_SUPPORT
 	default y
 
-if TRACING_SUPPORT
-
 menuconfig FTRACE
 	bool "Tracers"
+	depends on TRACING_SUPPORT
 	default y if DEBUG_KERNEL
 	help
 	  Enable the kernel tracing infrastructure.
@@ -1037,6 +1036,3 @@ config HIST_TRIGGERS_DEBUG
           If unsure, say N.
 
 endif # FTRACE
-
-endif # TRACING_SUPPORT
-
diff --git a/kernel/trace/Makefile b/kernel/trace/Makefile
index b1c47ccf4f73..6de5d4d63165 100644
--- a/kernel/trace/Makefile
+++ b/kernel/trace/Makefile
@@ -77,6 +77,7 @@ obj-$(CONFIG_EVENT_TRACING) += trace_event_perf.o
 endif
 obj-$(CONFIG_EVENT_TRACING) += trace_events_filter.o
 obj-$(CONFIG_EVENT_TRACING) += trace_events_trigger.o
+obj-$(CONFIG_PROBE_EVENTS) += trace_eprobe.o
 obj-$(CONFIG_TRACE_EVENT_INJECT) += trace_events_inject.o
 obj-$(CONFIG_SYNTH_EVENTS) += trace_events_synth.o
 obj-$(CONFIG_HIST_TRIGGERS) += trace_events_hist.o
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index e592d1df6f88..c5a3fbf19617 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -2111,7 +2111,7 @@ int ring_buffer_resize(struct trace_buffer *buffer, unsigned long size,
 			}
 		}
 
-		get_online_cpus();
+		cpus_read_lock();
 		/*
 		 * Fire off all the required work handlers
 		 * We can't schedule on offline CPUs, but it's not necessary
@@ -2143,7 +2143,7 @@ int ring_buffer_resize(struct trace_buffer *buffer, unsigned long size,
 			cpu_buffer->nr_pages_to_update = 0;
 		}
 
-		put_online_cpus();
+		cpus_read_unlock();
 	} else {
 		cpu_buffer = buffer->buffers[cpu_id];
 
@@ -2171,7 +2171,7 @@ int ring_buffer_resize(struct trace_buffer *buffer, unsigned long size,
 			goto out_err;
 		}
 
-		get_online_cpus();
+		cpus_read_lock();
 
 		/* Can't run something on an offline CPU. */
 		if (!cpu_online(cpu_id))
@@ -2183,7 +2183,7 @@ int ring_buffer_resize(struct trace_buffer *buffer, unsigned long size,
 		}
 
 		cpu_buffer->nr_pages_to_update = 0;
-		put_online_cpus();
+		cpus_read_unlock();
 	}
 
  out:
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 2755534b0737..2dbf797aa133 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -3697,11 +3697,11 @@ static bool trace_safe_str(struct trace_iterator *iter, const char *str)
 		return false;
 
 	event = container_of(trace_event, struct trace_event_call, event);
-	if (!event->mod)
+	if ((event->flags & TRACE_EVENT_FL_DYNAMIC) || !event->module)
 		return false;
 
 	/* Would rather have rodata, but this will suffice */
-	if (within_module_core(addr, event->mod))
+	if (within_module_core(addr, event->module))
 		return true;
 
 	return false;
@@ -5543,6 +5543,7 @@ static const char readme_msg[] =
 #ifdef CONFIG_HIST_TRIGGERS
 	"\t           s:[synthetic/]<event> <field> [<field>]\n"
 #endif
+	"\t           e[:[<group>/]<event>] <attached-group>.<attached-event> [<args>]\n"
 	"\t           -:[<group>/]<event>\n"
 #ifdef CONFIG_KPROBE_EVENTS
 	"\t    place: [<module>:]<symbol>[+<offset>]|<memaddr>\n"
@@ -5552,7 +5553,7 @@ static const char readme_msg[] =
   "   place (uprobe): <path>:<offset>[%return][(ref_ctr_offset)]\n"
 #endif
 	"\t     args: <name>=fetcharg[:type]\n"
-	"\t fetcharg: %<register>, @<address>, @<symbol>[+|-<offset>],\n"
+	"\t fetcharg: (%<register>|$<efield>), @<address>, @<symbol>[+|-<offset>],\n"
 #ifdef CONFIG_HAVE_FUNCTION_ARG_ACCESS_API
 	"\t           $stack<index>, $stack, $retval, $comm, $arg<N>,\n"
 #else
@@ -5567,6 +5568,8 @@ static const char readme_msg[] =
 	"\t    stype: u8/u16/u32/u64, s8/s16/s32/s64, pid_t,\n"
 	"\t           [unsigned] char/int/long\n"
 #endif
+	"\t    efield: For event probes ('e' types), the field is on of the fields\n"
+	"\t            of the <attached-group>/<attached-event>.\n"
 #endif
 	"  events/\t\t- Directory containing all trace event subsystems:\n"
 	"      enable\t\t- Write 0/1 to enable/disable tracing of all events\n"
@@ -5654,6 +5657,7 @@ static const char readme_msg[] =
 	"\t            .execname   display a common_pid as a program name\n"
 	"\t            .syscall    display a syscall id as a syscall name\n"
 	"\t            .log2       display log2 value rather than raw number\n"
+	"\t            .buckets=size  display values in groups of size rather than raw number\n"
 	"\t            .usecs      display a common_timestamp in microseconds\n\n"
 	"\t    The 'pause' parameter can be used to pause an existing hist\n"
 	"\t    trigger or to start a hist trigger but not log any events\n"
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index 4a0e693000c6..b7c0f8e160fb 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -126,6 +126,11 @@ struct kprobe_trace_entry_head {
 	unsigned long		ip;
 };
 
+struct eprobe_trace_entry_head {
+	struct trace_entry	ent;
+	unsigned int		type;
+};
+
 struct kretprobe_trace_entry_head {
 	struct trace_entry	ent;
 	unsigned long		func;
@@ -1508,9 +1513,14 @@ static inline int register_trigger_hist_enable_disable_cmds(void) { return 0; }
 extern int register_trigger_cmds(void);
 extern void clear_event_triggers(struct trace_array *tr);
 
+enum {
+	EVENT_TRIGGER_FL_PROBE		= BIT(0),
+};
+
 struct event_trigger_data {
 	unsigned long			count;
 	int				ref;
+	int				flags;
 	struct event_trigger_ops	*ops;
 	struct event_command		*cmd_ops;
 	struct event_filter __rcu	*filter;
@@ -1918,6 +1928,14 @@ static inline bool is_good_name(const char *name)
 	return true;
 }
 
+/* Convert certain expected symbols into '_' when generating event names */
+static inline void sanitize_event_name(char *name)
+{
+	while (*name++ != '\0')
+		if (*name == ':' || *name == '.')
+			*name = '_';
+}
+
 /*
  * This is a generic way to read and write a u64 value from a file in tracefs.
  *
diff --git a/kernel/trace/trace_boot.c b/kernel/trace/trace_boot.c
index 94ef2d099e32..1060b0446032 100644
--- a/kernel/trace/trace_boot.c
+++ b/kernel/trace/trace_boot.c
@@ -171,6 +171,290 @@ trace_boot_add_synth_event(struct xbc_node *node, const char *event)
 }
 #endif
 
+#ifdef CONFIG_HIST_TRIGGERS
+static int __init __printf(3, 4)
+append_printf(char **bufp, char *end, const char *fmt, ...)
+{
+	va_list args;
+	int ret;
+
+	if (*bufp == end)
+		return -ENOSPC;
+
+	va_start(args, fmt);
+	ret = vsnprintf(*bufp, end - *bufp, fmt, args);
+	if (ret < end - *bufp) {
+		*bufp += ret;
+	} else {
+		*bufp = end;
+		ret = -ERANGE;
+	}
+	va_end(args);
+
+	return ret;
+}
+
+static int __init
+append_str_nospace(char **bufp, char *end, const char *str)
+{
+	char *p = *bufp;
+	int len;
+
+	while (p < end - 1 && *str != '\0') {
+		if (!isspace(*str))
+			*(p++) = *str;
+		str++;
+	}
+	*p = '\0';
+	if (p == end - 1) {
+		*bufp = end;
+		return -ENOSPC;
+	}
+	len = p - *bufp;
+	*bufp = p;
+	return (int)len;
+}
+
+static int __init
+trace_boot_hist_add_array(struct xbc_node *hnode, char **bufp,
+			  char *end, const char *key)
+{
+	struct xbc_node *knode, *anode;
+	const char *p;
+	char sep;
+
+	knode = xbc_node_find_child(hnode, key);
+	if (knode) {
+		anode = xbc_node_get_child(knode);
+		if (!anode) {
+			pr_err("hist.%s requires value(s).\n", key);
+			return -EINVAL;
+		}
+
+		append_printf(bufp, end, ":%s", key);
+		sep = '=';
+		xbc_array_for_each_value(anode, p) {
+			append_printf(bufp, end, "%c%s", sep, p);
+			if (sep == '=')
+				sep = ',';
+		}
+	} else
+		return -ENOENT;
+
+	return 0;
+}
+
+static int __init
+trace_boot_hist_add_one_handler(struct xbc_node *hnode, char **bufp,
+				char *end, const char *handler,
+				const char *param)
+{
+	struct xbc_node *knode, *anode;
+	const char *p;
+	char sep;
+
+	/* Compose 'handler' parameter */
+	p = xbc_node_find_value(hnode, param, NULL);
+	if (!p) {
+		pr_err("hist.%s requires '%s' option.\n",
+		       xbc_node_get_data(hnode), param);
+		return -EINVAL;
+	}
+	append_printf(bufp, end, ":%s(%s)", handler, p);
+
+	/* Compose 'action' parameter */
+	knode = xbc_node_find_child(hnode, "trace");
+	if (!knode)
+		knode = xbc_node_find_child(hnode, "save");
+
+	if (knode) {
+		anode = xbc_node_get_child(knode);
+		if (!anode || !xbc_node_is_value(anode)) {
+			pr_err("hist.%s.%s requires value(s).\n",
+			       xbc_node_get_data(hnode),
+			       xbc_node_get_data(knode));
+			return -EINVAL;
+		}
+
+		append_printf(bufp, end, ".%s", xbc_node_get_data(knode));
+		sep = '(';
+		xbc_array_for_each_value(anode, p) {
+			append_printf(bufp, end, "%c%s", sep, p);
+			if (sep == '(')
+				sep = ',';
+		}
+		append_printf(bufp, end, ")");
+	} else if (xbc_node_find_child(hnode, "snapshot")) {
+		append_printf(bufp, end, ".snapshot()");
+	} else {
+		pr_err("hist.%s requires an action.\n",
+		       xbc_node_get_data(hnode));
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int __init
+trace_boot_hist_add_handlers(struct xbc_node *hnode, char **bufp,
+			     char *end, const char *param)
+{
+	struct xbc_node *node;
+	const char *p, *handler;
+	int ret;
+
+	handler = xbc_node_get_data(hnode);
+
+	xbc_node_for_each_subkey(hnode, node) {
+		p = xbc_node_get_data(node);
+		if (!isdigit(p[0]))
+			continue;
+		/* All digit started node should be instances. */
+		ret = trace_boot_hist_add_one_handler(node, bufp, end, handler, param);
+		if (ret < 0)
+			break;
+	}
+
+	if (xbc_node_find_child(hnode, param))
+		ret = trace_boot_hist_add_one_handler(hnode, bufp, end, handler, param);
+
+	return ret;
+}
+
+/*
+ * Histogram boottime tracing syntax.
+ *
+ * ftrace.[instance.INSTANCE.]event.GROUP.EVENT.hist[.N] {
+ *	keys = <KEY>[,...]
+ *	values = <VAL>[,...]
+ *	sort = <SORT-KEY>[,...]
+ *	size = <ENTRIES>
+ *	name = <HISTNAME>
+ *	var { <VAR> = <EXPR> ... }
+ *	pause|continue|clear
+ *	onmax|onchange[.N] { var = <VAR>; <ACTION> [= <PARAM>] }
+ *	onmatch[.N] { event = <EVENT>; <ACTION> [= <PARAM>] }
+ *	filter = <FILTER>
+ * }
+ *
+ * Where <ACTION> are;
+ *
+ *	trace = <EVENT>, <ARG1>[, ...]
+ *	save = <ARG1>[, ...]
+ *	snapshot
+ */
+static int __init
+trace_boot_compose_hist_cmd(struct xbc_node *hnode, char *buf, size_t size)
+{
+	struct xbc_node *node, *knode;
+	char *end = buf + size;
+	const char *p;
+	int ret = 0;
+
+	append_printf(&buf, end, "hist");
+
+	ret = trace_boot_hist_add_array(hnode, &buf, end, "keys");
+	if (ret < 0) {
+		if (ret == -ENOENT)
+			pr_err("hist requires keys.\n");
+		return -EINVAL;
+	}
+
+	ret = trace_boot_hist_add_array(hnode, &buf, end, "values");
+	if (ret == -EINVAL)
+		return ret;
+	ret = trace_boot_hist_add_array(hnode, &buf, end, "sort");
+	if (ret == -EINVAL)
+		return ret;
+
+	p = xbc_node_find_value(hnode, "size", NULL);
+	if (p)
+		append_printf(&buf, end, ":size=%s", p);
+
+	p = xbc_node_find_value(hnode, "name", NULL);
+	if (p)
+		append_printf(&buf, end, ":name=%s", p);
+
+	node = xbc_node_find_child(hnode, "var");
+	if (node) {
+		xbc_node_for_each_key_value(node, knode, p) {
+			/* Expression must not include spaces. */
+			append_printf(&buf, end, ":%s=",
+				      xbc_node_get_data(knode));
+			append_str_nospace(&buf, end, p);
+		}
+	}
+
+	/* Histogram control attributes (mutual exclusive) */
+	if (xbc_node_find_child(hnode, "pause"))
+		append_printf(&buf, end, ":pause");
+	else if (xbc_node_find_child(hnode, "continue"))
+		append_printf(&buf, end, ":continue");
+	else if (xbc_node_find_child(hnode, "clear"))
+		append_printf(&buf, end, ":clear");
+
+	/* Histogram handler and actions */
+	node = xbc_node_find_child(hnode, "onmax");
+	if (node && trace_boot_hist_add_handlers(node, &buf, end, "var") < 0)
+		return -EINVAL;
+	node = xbc_node_find_child(hnode, "onchange");
+	if (node && trace_boot_hist_add_handlers(node, &buf, end, "var") < 0)
+		return -EINVAL;
+	node = xbc_node_find_child(hnode, "onmatch");
+	if (node && trace_boot_hist_add_handlers(node, &buf, end, "event") < 0)
+		return -EINVAL;
+
+	p = xbc_node_find_value(hnode, "filter", NULL);
+	if (p)
+		append_printf(&buf, end, " if %s", p);
+
+	if (buf == end) {
+		pr_err("hist exceeds the max command length.\n");
+		return -E2BIG;
+	}
+
+	return 0;
+}
+
+static void __init
+trace_boot_init_histograms(struct trace_event_file *file,
+			   struct xbc_node *hnode, char *buf, size_t size)
+{
+	struct xbc_node *node;
+	const char *p;
+	char *tmp;
+
+	xbc_node_for_each_subkey(hnode, node) {
+		p = xbc_node_get_data(node);
+		if (!isdigit(p[0]))
+			continue;
+		/* All digit started node should be instances. */
+		if (trace_boot_compose_hist_cmd(node, buf, size) == 0) {
+			tmp = kstrdup(buf, GFP_KERNEL);
+			if (trigger_process_regex(file, buf) < 0)
+				pr_err("Failed to apply hist trigger: %s\n", tmp);
+			kfree(tmp);
+		}
+	}
+
+	if (xbc_node_find_child(hnode, "keys")) {
+		if (trace_boot_compose_hist_cmd(hnode, buf, size) == 0) {
+			tmp = kstrdup(buf, GFP_KERNEL);
+			if (trigger_process_regex(file, buf) < 0)
+				pr_err("Failed to apply hist trigger: %s\n", tmp);
+			kfree(tmp);
+		}
+	}
+}
+#else
+static void __init
+trace_boot_init_histograms(struct trace_event_file *file,
+			   struct xbc_node *hnode, char *buf, size_t size)
+{
+	/* do nothing */
+}
+#endif
+
 static void __init
 trace_boot_init_one_event(struct trace_array *tr, struct xbc_node *gnode,
 			  struct xbc_node *enode)
@@ -205,12 +489,18 @@ trace_boot_init_one_event(struct trace_array *tr, struct xbc_node *gnode,
 			pr_err("Failed to apply filter: %s\n", buf);
 	}
 
-	xbc_node_for_each_array_value(enode, "actions", anode, p) {
-		if (strlcpy(buf, p, ARRAY_SIZE(buf)) >= ARRAY_SIZE(buf))
-			pr_err("action string is too long: %s\n", p);
-		else if (trigger_process_regex(file, buf) < 0)
-			pr_err("Failed to apply an action: %s\n", buf);
-	}
+	if (IS_ENABLED(CONFIG_HIST_TRIGGERS)) {
+		xbc_node_for_each_array_value(enode, "actions", anode, p) {
+			if (strlcpy(buf, p, ARRAY_SIZE(buf)) >= ARRAY_SIZE(buf))
+				pr_err("action string is too long: %s\n", p);
+			else if (trigger_process_regex(file, buf) < 0)
+				pr_err("Failed to apply an action: %s\n", p);
+		}
+		anode = xbc_node_find_child(enode, "hist");
+		if (anode)
+			trace_boot_init_histograms(file, anode, buf, ARRAY_SIZE(buf));
+	} else if (xbc_node_find_value(enode, "actions", NULL))
+		pr_err("Failed to apply event actions because CONFIG_HIST_TRIGGERS is not set.\n");
 
 	if (xbc_node_find_value(enode, "enable", NULL)) {
 		if (trace_event_enable_disable(file, 1, 0) < 0)
diff --git a/kernel/trace/trace_dynevent.c b/kernel/trace/trace_dynevent.c
index e57cc0870892..1110112e55bd 100644
--- a/kernel/trace/trace_dynevent.c
+++ b/kernel/trace/trace_dynevent.c
@@ -13,11 +13,49 @@
 #include <linux/tracefs.h>
 
 #include "trace.h"
+#include "trace_output.h"	/* for trace_event_sem */
 #include "trace_dynevent.h"
 
 static DEFINE_MUTEX(dyn_event_ops_mutex);
 static LIST_HEAD(dyn_event_ops_list);
 
+bool trace_event_dyn_try_get_ref(struct trace_event_call *dyn_call)
+{
+	struct trace_event_call *call;
+	bool ret = false;
+
+	if (WARN_ON_ONCE(!(dyn_call->flags & TRACE_EVENT_FL_DYNAMIC)))
+		return false;
+
+	down_read(&trace_event_sem);
+	list_for_each_entry(call, &ftrace_events, list) {
+		if (call == dyn_call) {
+			atomic_inc(&dyn_call->refcnt);
+			ret = true;
+		}
+	}
+	up_read(&trace_event_sem);
+	return ret;
+}
+
+void trace_event_dyn_put_ref(struct trace_event_call *call)
+{
+	if (WARN_ON_ONCE(!(call->flags & TRACE_EVENT_FL_DYNAMIC)))
+		return;
+
+	if (WARN_ON_ONCE(atomic_read(&call->refcnt) <= 0)) {
+		atomic_set(&call->refcnt, 0);
+		return;
+	}
+
+	atomic_dec(&call->refcnt);
+}
+
+bool trace_event_dyn_busy(struct trace_event_call *call)
+{
+	return atomic_read(&call->refcnt) != 0;
+}
+
 int dyn_event_register(struct dyn_event_operations *ops)
 {
 	if (!ops || !ops->create || !ops->show || !ops->is_busy ||
diff --git a/kernel/trace/trace_dynevent.h b/kernel/trace/trace_dynevent.h
index 7754936b57ee..936477a111d3 100644
--- a/kernel/trace/trace_dynevent.h
+++ b/kernel/trace/trace_dynevent.h
@@ -76,13 +76,15 @@ int dyn_event_init(struct dyn_event *ev, struct dyn_event_operations *ops)
 	return 0;
 }
 
-static inline int dyn_event_add(struct dyn_event *ev)
+static inline int dyn_event_add(struct dyn_event *ev,
+				struct trace_event_call *call)
 {
 	lockdep_assert_held(&event_mutex);
 
 	if (!ev || !ev->ops)
 		return -EINVAL;
 
+	call->flags |= TRACE_EVENT_FL_DYNAMIC;
 	list_add_tail(&ev->list, &dyn_event_list);
 	return 0;
 }
diff --git a/kernel/trace/trace_eprobe.c b/kernel/trace/trace_eprobe.c
new file mode 100644
index 000000000000..56a96e9750cf
--- /dev/null
+++ b/kernel/trace/trace_eprobe.c
@@ -0,0 +1,903 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * event probes
+ *
+ * Part of this code was copied from kernel/trace/trace_kprobe.c written by
+ * Masami Hiramatsu <mhiramat@kernel.org>
+ *
+ * Copyright (C) 2021, VMware Inc, Steven Rostedt <rostedt@goodmis.org>
+ * Copyright (C) 2021, VMware Inc, Tzvetomir Stoyanov tz.stoyanov@gmail.com>
+ *
+ */
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/ftrace.h>
+
+#include "trace_dynevent.h"
+#include "trace_probe.h"
+#include "trace_probe_tmpl.h"
+
+#define EPROBE_EVENT_SYSTEM "eprobes"
+
+struct trace_eprobe {
+	/* tracepoint system */
+	const char *event_system;
+
+	/* tracepoint event */
+	const char *event_name;
+
+	struct trace_event_call *event;
+
+	struct dyn_event	devent;
+	struct trace_probe	tp;
+};
+
+struct eprobe_data {
+	struct trace_event_file	*file;
+	struct trace_eprobe	*ep;
+};
+
+static int __trace_eprobe_create(int argc, const char *argv[]);
+
+static void trace_event_probe_cleanup(struct trace_eprobe *ep)
+{
+	if (!ep)
+		return;
+	trace_probe_cleanup(&ep->tp);
+	kfree(ep->event_name);
+	kfree(ep->event_system);
+	if (ep->event)
+		trace_event_put_ref(ep->event);
+	kfree(ep);
+}
+
+static struct trace_eprobe *to_trace_eprobe(struct dyn_event *ev)
+{
+	return container_of(ev, struct trace_eprobe, devent);
+}
+
+static int eprobe_dyn_event_create(const char *raw_command)
+{
+	return trace_probe_create(raw_command, __trace_eprobe_create);
+}
+
+static int eprobe_dyn_event_show(struct seq_file *m, struct dyn_event *ev)
+{
+	struct trace_eprobe *ep = to_trace_eprobe(ev);
+	int i;
+
+	seq_printf(m, "e:%s/%s", trace_probe_group_name(&ep->tp),
+				trace_probe_name(&ep->tp));
+	seq_printf(m, " %s.%s", ep->event_system, ep->event_name);
+
+	for (i = 0; i < ep->tp.nr_args; i++)
+		seq_printf(m, " %s=%s", ep->tp.args[i].name, ep->tp.args[i].comm);
+	seq_putc(m, '\n');
+
+	return 0;
+}
+
+static int unregister_trace_eprobe(struct trace_eprobe *ep)
+{
+	/* If other probes are on the event, just unregister eprobe */
+	if (trace_probe_has_sibling(&ep->tp))
+		goto unreg;
+
+	/* Enabled event can not be unregistered */
+	if (trace_probe_is_enabled(&ep->tp))
+		return -EBUSY;
+
+	/* Will fail if probe is being used by ftrace or perf */
+	if (trace_probe_unregister_event_call(&ep->tp))
+		return -EBUSY;
+
+unreg:
+	dyn_event_remove(&ep->devent);
+	trace_probe_unlink(&ep->tp);
+
+	return 0;
+}
+
+static int eprobe_dyn_event_release(struct dyn_event *ev)
+{
+	struct trace_eprobe *ep = to_trace_eprobe(ev);
+	int ret = unregister_trace_eprobe(ep);
+
+	if (!ret)
+		trace_event_probe_cleanup(ep);
+	return ret;
+}
+
+static bool eprobe_dyn_event_is_busy(struct dyn_event *ev)
+{
+	struct trace_eprobe *ep = to_trace_eprobe(ev);
+
+	return trace_probe_is_enabled(&ep->tp);
+}
+
+static bool eprobe_dyn_event_match(const char *system, const char *event,
+			int argc, const char **argv, struct dyn_event *ev)
+{
+	struct trace_eprobe *ep = to_trace_eprobe(ev);
+
+	return strcmp(trace_probe_name(&ep->tp), event) == 0 &&
+	    (!system || strcmp(trace_probe_group_name(&ep->tp), system) == 0) &&
+	    trace_probe_match_command_args(&ep->tp, argc, argv);
+}
+
+static struct dyn_event_operations eprobe_dyn_event_ops = {
+	.create = eprobe_dyn_event_create,
+	.show = eprobe_dyn_event_show,
+	.is_busy = eprobe_dyn_event_is_busy,
+	.free = eprobe_dyn_event_release,
+	.match = eprobe_dyn_event_match,
+};
+
+static struct trace_eprobe *alloc_event_probe(const char *group,
+					      const char *this_event,
+					      struct trace_event_call *event,
+					      int nargs)
+{
+	struct trace_eprobe *ep;
+	const char *event_name;
+	const char *sys_name;
+	int ret = -ENOMEM;
+
+	if (!event)
+		return ERR_PTR(-ENODEV);
+
+	sys_name = event->class->system;
+	event_name = trace_event_name(event);
+
+	ep = kzalloc(struct_size(ep, tp.args, nargs), GFP_KERNEL);
+	if (!ep) {
+		trace_event_put_ref(ep->event);
+		goto error;
+	}
+	ep->event = event;
+	ep->event_name = kstrdup(event_name, GFP_KERNEL);
+	if (!ep->event_name)
+		goto error;
+	ep->event_system = kstrdup(sys_name, GFP_KERNEL);
+	if (!ep->event_system)
+		goto error;
+
+	ret = trace_probe_init(&ep->tp, this_event, group, false);
+	if (ret < 0)
+		goto error;
+
+	dyn_event_init(&ep->devent, &eprobe_dyn_event_ops);
+	return ep;
+error:
+	trace_event_probe_cleanup(ep);
+	return ERR_PTR(ret);
+}
+
+static int trace_eprobe_tp_arg_update(struct trace_eprobe *ep, int i)
+{
+	struct probe_arg *parg = &ep->tp.args[i];
+	struct ftrace_event_field *field;
+	struct list_head *head;
+
+	head = trace_get_fields(ep->event);
+	list_for_each_entry(field, head, link) {
+		if (!strcmp(parg->code->data, field->name)) {
+			kfree(parg->code->data);
+			parg->code->data = field;
+			return 0;
+		}
+	}
+	kfree(parg->code->data);
+	parg->code->data = NULL;
+	return -ENOENT;
+}
+
+static int eprobe_event_define_fields(struct trace_event_call *event_call)
+{
+	int ret;
+	struct eprobe_trace_entry_head field;
+	struct trace_probe *tp;
+
+	tp = trace_probe_primary_from_call(event_call);
+	if (WARN_ON_ONCE(!tp))
+		return -ENOENT;
+
+	DEFINE_FIELD(unsigned int, type, FIELD_STRING_TYPE, 0);
+
+	return traceprobe_define_arg_fields(event_call, sizeof(field), tp);
+}
+
+static struct trace_event_fields eprobe_fields_array[] = {
+	{ .type = TRACE_FUNCTION_TYPE,
+	  .define_fields = eprobe_event_define_fields },
+	{}
+};
+
+/* Event entry printers */
+static enum print_line_t
+print_eprobe_event(struct trace_iterator *iter, int flags,
+		   struct trace_event *event)
+{
+	struct eprobe_trace_entry_head *field;
+	struct trace_event_call *pevent;
+	struct trace_event *probed_event;
+	struct trace_seq *s = &iter->seq;
+	struct trace_probe *tp;
+
+	field = (struct eprobe_trace_entry_head *)iter->ent;
+	tp = trace_probe_primary_from_call(
+		container_of(event, struct trace_event_call, event));
+	if (WARN_ON_ONCE(!tp))
+		goto out;
+
+	trace_seq_printf(s, "%s: (", trace_probe_name(tp));
+
+	probed_event = ftrace_find_event(field->type);
+	if (probed_event) {
+		pevent = container_of(probed_event, struct trace_event_call, event);
+		trace_seq_printf(s, "%s.%s", pevent->class->system,
+				 trace_event_name(pevent));
+	} else {
+		trace_seq_printf(s, "%u", field->type);
+	}
+
+	trace_seq_putc(s, ')');
+
+	if (print_probe_args(s, tp->args, tp->nr_args,
+			     (u8 *)&field[1], field) < 0)
+		goto out;
+
+	trace_seq_putc(s, '\n');
+ out:
+	return trace_handle_return(s);
+}
+
+static unsigned long get_event_field(struct fetch_insn *code, void *rec)
+{
+	struct ftrace_event_field *field = code->data;
+	unsigned long val;
+	void *addr;
+
+	addr = rec + field->offset;
+
+	switch (field->size) {
+	case 1:
+		if (field->is_signed)
+			val = *(char *)addr;
+		else
+			val = *(unsigned char *)addr;
+		break;
+	case 2:
+		if (field->is_signed)
+			val = *(short *)addr;
+		else
+			val = *(unsigned short *)addr;
+		break;
+	case 4:
+		if (field->is_signed)
+			val = *(int *)addr;
+		else
+			val = *(unsigned int *)addr;
+		break;
+	default:
+		if (field->is_signed)
+			val = *(long *)addr;
+		else
+			val = *(unsigned long *)addr;
+		break;
+	}
+	return val;
+}
+
+static int get_eprobe_size(struct trace_probe *tp, void *rec)
+{
+	struct probe_arg *arg;
+	int i, len, ret = 0;
+
+	for (i = 0; i < tp->nr_args; i++) {
+		arg = tp->args + i;
+		if (unlikely(arg->dynamic)) {
+			unsigned long val;
+
+			val = get_event_field(arg->code, rec);
+			len = process_fetch_insn_bottom(arg->code + 1, val, NULL, NULL);
+			if (len > 0)
+				ret += len;
+		}
+	}
+
+	return ret;
+}
+
+/* Kprobe specific fetch functions */
+
+/* Note that we don't verify it, since the code does not come from user space */
+static int
+process_fetch_insn(struct fetch_insn *code, void *rec, void *dest,
+		   void *base)
+{
+	unsigned long val;
+
+	val = get_event_field(code, rec);
+	return process_fetch_insn_bottom(code + 1, val, dest, base);
+}
+NOKPROBE_SYMBOL(process_fetch_insn)
+
+/* Return the length of string -- including null terminal byte */
+static nokprobe_inline int
+fetch_store_strlen_user(unsigned long addr)
+{
+	const void __user *uaddr =  (__force const void __user *)addr;
+
+	return strnlen_user_nofault(uaddr, MAX_STRING_SIZE);
+}
+
+/* Return the length of string -- including null terminal byte */
+static nokprobe_inline int
+fetch_store_strlen(unsigned long addr)
+{
+	int ret, len = 0;
+	u8 c;
+
+#ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
+	if (addr < TASK_SIZE)
+		return fetch_store_strlen_user(addr);
+#endif
+
+	do {
+		ret = copy_from_kernel_nofault(&c, (u8 *)addr + len, 1);
+		len++;
+	} while (c && ret == 0 && len < MAX_STRING_SIZE);
+
+	return (ret < 0) ? ret : len;
+}
+
+/*
+ * Fetch a null-terminated string from user. Caller MUST set *(u32 *)buf
+ * with max length and relative data location.
+ */
+static nokprobe_inline int
+fetch_store_string_user(unsigned long addr, void *dest, void *base)
+{
+	const void __user *uaddr =  (__force const void __user *)addr;
+	int maxlen = get_loc_len(*(u32 *)dest);
+	void *__dest;
+	long ret;
+
+	if (unlikely(!maxlen))
+		return -ENOMEM;
+
+	__dest = get_loc_data(dest, base);
+
+	ret = strncpy_from_user_nofault(__dest, uaddr, maxlen);
+	if (ret >= 0)
+		*(u32 *)dest = make_data_loc(ret, __dest - base);
+
+	return ret;
+}
+
+/*
+ * Fetch a null-terminated string. Caller MUST set *(u32 *)buf with max
+ * length and relative data location.
+ */
+static nokprobe_inline int
+fetch_store_string(unsigned long addr, void *dest, void *base)
+{
+	int maxlen = get_loc_len(*(u32 *)dest);
+	void *__dest;
+	long ret;
+
+#ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
+	if ((unsigned long)addr < TASK_SIZE)
+		return fetch_store_string_user(addr, dest, base);
+#endif
+
+	if (unlikely(!maxlen))
+		return -ENOMEM;
+
+	__dest = get_loc_data(dest, base);
+
+	/*
+	 * Try to get string again, since the string can be changed while
+	 * probing.
+	 */
+	ret = strncpy_from_kernel_nofault(__dest, (void *)addr, maxlen);
+	if (ret >= 0)
+		*(u32 *)dest = make_data_loc(ret, __dest - base);
+
+	return ret;
+}
+
+static nokprobe_inline int
+probe_mem_read_user(void *dest, void *src, size_t size)
+{
+	const void __user *uaddr =  (__force const void __user *)src;
+
+	return copy_from_user_nofault(dest, uaddr, size);
+}
+
+static nokprobe_inline int
+probe_mem_read(void *dest, void *src, size_t size)
+{
+#ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
+	if ((unsigned long)src < TASK_SIZE)
+		return probe_mem_read_user(dest, src, size);
+#endif
+	return copy_from_kernel_nofault(dest, src, size);
+}
+
+/* eprobe handler */
+static inline void
+__eprobe_trace_func(struct eprobe_data *edata, void *rec)
+{
+	struct eprobe_trace_entry_head *entry;
+	struct trace_event_call *call = trace_probe_event_call(&edata->ep->tp);
+	struct trace_event_buffer fbuffer;
+	int dsize;
+
+	if (WARN_ON_ONCE(call != edata->file->event_call))
+		return;
+
+	if (trace_trigger_soft_disabled(edata->file))
+		return;
+
+	fbuffer.trace_ctx = tracing_gen_ctx();
+	fbuffer.trace_file = edata->file;
+
+	dsize = get_eprobe_size(&edata->ep->tp, rec);
+	fbuffer.regs = NULL;
+
+	fbuffer.event =
+		trace_event_buffer_lock_reserve(&fbuffer.buffer, edata->file,
+					call->event.type,
+					sizeof(*entry) + edata->ep->tp.size + dsize,
+					fbuffer.trace_ctx);
+	if (!fbuffer.event)
+		return;
+
+	entry = fbuffer.entry = ring_buffer_event_data(fbuffer.event);
+	if (edata->ep->event)
+		entry->type = edata->ep->event->event.type;
+	else
+		entry->type = 0;
+	store_trace_args(&entry[1], &edata->ep->tp, rec, sizeof(*entry), dsize);
+
+	trace_event_buffer_commit(&fbuffer);
+}
+
+/*
+ * The event probe implementation uses event triggers to get access to
+ * the event it is attached to, but is not an actual trigger. The below
+ * functions are just stubs to fulfill what is needed to use the trigger
+ * infrastructure.
+ */
+static int eprobe_trigger_init(struct event_trigger_ops *ops,
+			       struct event_trigger_data *data)
+{
+	return 0;
+}
+
+static void eprobe_trigger_free(struct event_trigger_ops *ops,
+				struct event_trigger_data *data)
+{
+
+}
+
+static int eprobe_trigger_print(struct seq_file *m,
+				struct event_trigger_ops *ops,
+				struct event_trigger_data *data)
+{
+	/* Do not print eprobe event triggers */
+	return 0;
+}
+
+static void eprobe_trigger_func(struct event_trigger_data *data,
+				struct trace_buffer *buffer, void *rec,
+				struct ring_buffer_event *rbe)
+{
+	struct eprobe_data *edata = data->private_data;
+
+	__eprobe_trace_func(edata, rec);
+}
+
+static struct event_trigger_ops eprobe_trigger_ops = {
+	.func			= eprobe_trigger_func,
+	.print			= eprobe_trigger_print,
+	.init			= eprobe_trigger_init,
+	.free			= eprobe_trigger_free,
+};
+
+static int eprobe_trigger_cmd_func(struct event_command *cmd_ops,
+				   struct trace_event_file *file,
+				   char *glob, char *cmd, char *param)
+{
+	return -1;
+}
+
+static int eprobe_trigger_reg_func(char *glob, struct event_trigger_ops *ops,
+				 struct event_trigger_data *data,
+				 struct trace_event_file *file)
+{
+	return -1;
+}
+
+static void eprobe_trigger_unreg_func(char *glob, struct event_trigger_ops *ops,
+				    struct event_trigger_data *data,
+				    struct trace_event_file *file)
+{
+
+}
+
+static struct event_trigger_ops *eprobe_trigger_get_ops(char *cmd,
+							char *param)
+{
+	return &eprobe_trigger_ops;
+}
+
+static struct event_command event_trigger_cmd = {
+	.name			= "eprobe",
+	.trigger_type		= ETT_EVENT_EPROBE,
+	.flags			= EVENT_CMD_FL_NEEDS_REC,
+	.func			= eprobe_trigger_cmd_func,
+	.reg			= eprobe_trigger_reg_func,
+	.unreg			= eprobe_trigger_unreg_func,
+	.unreg_all		= NULL,
+	.get_trigger_ops	= eprobe_trigger_get_ops,
+	.set_filter		= NULL,
+};
+
+static struct event_trigger_data *
+new_eprobe_trigger(struct trace_eprobe *ep, struct trace_event_file *file)
+{
+	struct event_trigger_data *trigger;
+	struct eprobe_data *edata;
+
+	edata = kzalloc(sizeof(*edata), GFP_KERNEL);
+	trigger = kzalloc(sizeof(*trigger), GFP_KERNEL);
+	if (!trigger || !edata) {
+		kfree(edata);
+		kfree(trigger);
+		return ERR_PTR(-ENOMEM);
+	}
+
+	trigger->flags = EVENT_TRIGGER_FL_PROBE;
+	trigger->count = -1;
+	trigger->ops = &eprobe_trigger_ops;
+
+	/*
+	 * EVENT PROBE triggers are not registered as commands with
+	 * register_event_command(), as they are not controlled by the user
+	 * from the trigger file
+	 */
+	trigger->cmd_ops = &event_trigger_cmd;
+
+	INIT_LIST_HEAD(&trigger->list);
+	RCU_INIT_POINTER(trigger->filter, NULL);
+
+	edata->file = file;
+	edata->ep = ep;
+	trigger->private_data = edata;
+
+	return trigger;
+}
+
+static int enable_eprobe(struct trace_eprobe *ep,
+			 struct trace_event_file *eprobe_file)
+{
+	struct event_trigger_data *trigger;
+	struct trace_event_file *file;
+	struct trace_array *tr = eprobe_file->tr;
+
+	file = find_event_file(tr, ep->event_system, ep->event_name);
+	if (!file)
+		return -ENOENT;
+	trigger = new_eprobe_trigger(ep, eprobe_file);
+	if (IS_ERR(trigger))
+		return PTR_ERR(trigger);
+
+	list_add_tail_rcu(&trigger->list, &file->triggers);
+
+	trace_event_trigger_enable_disable(file, 1);
+	update_cond_flag(file);
+
+	return 0;
+}
+
+static struct trace_event_functions eprobe_funcs = {
+	.trace		= print_eprobe_event
+};
+
+static int disable_eprobe(struct trace_eprobe *ep,
+			  struct trace_array *tr)
+{
+	struct event_trigger_data *trigger;
+	struct trace_event_file *file;
+	struct eprobe_data *edata;
+
+	file = find_event_file(tr, ep->event_system, ep->event_name);
+	if (!file)
+		return -ENOENT;
+
+	list_for_each_entry(trigger, &file->triggers, list) {
+		if (!(trigger->flags & EVENT_TRIGGER_FL_PROBE))
+			continue;
+		edata = trigger->private_data;
+		if (edata->ep == ep)
+			break;
+	}
+	if (list_entry_is_head(trigger, &file->triggers, list))
+		return -ENODEV;
+
+	list_del_rcu(&trigger->list);
+
+	trace_event_trigger_enable_disable(file, 0);
+	update_cond_flag(file);
+	return 0;
+}
+
+static int enable_trace_eprobe(struct trace_event_call *call,
+			       struct trace_event_file *file)
+{
+	struct trace_probe *pos, *tp;
+	struct trace_eprobe *ep;
+	bool enabled;
+	int ret = 0;
+
+	tp = trace_probe_primary_from_call(call);
+	if (WARN_ON_ONCE(!tp))
+		return -ENODEV;
+	enabled = trace_probe_is_enabled(tp);
+
+	/* This also changes "enabled" state */
+	if (file) {
+		ret = trace_probe_add_file(tp, file);
+		if (ret)
+			return ret;
+	} else
+		trace_probe_set_flag(tp, TP_FLAG_PROFILE);
+
+	if (enabled)
+		return 0;
+
+	list_for_each_entry(pos, trace_probe_probe_list(tp), list) {
+		ep = container_of(pos, struct trace_eprobe, tp);
+		ret = enable_eprobe(ep, file);
+		if (ret)
+			break;
+		enabled = true;
+	}
+
+	if (ret) {
+		/* Failed to enable one of them. Roll back all */
+		if (enabled)
+			disable_eprobe(ep, file->tr);
+		if (file)
+			trace_probe_remove_file(tp, file);
+		else
+			trace_probe_clear_flag(tp, TP_FLAG_PROFILE);
+	}
+
+	return ret;
+}
+
+static int disable_trace_eprobe(struct trace_event_call *call,
+				struct trace_event_file *file)
+{
+	struct trace_probe *pos, *tp;
+	struct trace_eprobe *ep;
+
+	tp = trace_probe_primary_from_call(call);
+	if (WARN_ON_ONCE(!tp))
+		return -ENODEV;
+
+	if (file) {
+		if (!trace_probe_get_file_link(tp, file))
+			return -ENOENT;
+		if (!trace_probe_has_single_file(tp))
+			goto out;
+		trace_probe_clear_flag(tp, TP_FLAG_TRACE);
+	} else
+		trace_probe_clear_flag(tp, TP_FLAG_PROFILE);
+
+	if (!trace_probe_is_enabled(tp)) {
+		list_for_each_entry(pos, trace_probe_probe_list(tp), list) {
+			ep = container_of(pos, struct trace_eprobe, tp);
+			disable_eprobe(ep, file->tr);
+		}
+	}
+
+ out:
+	if (file)
+		/*
+		 * Synchronization is done in below function. For perf event,
+		 * file == NULL and perf_trace_event_unreg() calls
+		 * tracepoint_synchronize_unregister() to ensure synchronize
+		 * event. We don't need to care about it.
+		 */
+		trace_probe_remove_file(tp, file);
+
+	return 0;
+}
+
+static int eprobe_register(struct trace_event_call *event,
+			   enum trace_reg type, void *data)
+{
+	struct trace_event_file *file = data;
+
+	switch (type) {
+	case TRACE_REG_REGISTER:
+		return enable_trace_eprobe(event, file);
+	case TRACE_REG_UNREGISTER:
+		return disable_trace_eprobe(event, file);
+#ifdef CONFIG_PERF_EVENTS
+	case TRACE_REG_PERF_REGISTER:
+	case TRACE_REG_PERF_UNREGISTER:
+	case TRACE_REG_PERF_OPEN:
+	case TRACE_REG_PERF_CLOSE:
+	case TRACE_REG_PERF_ADD:
+	case TRACE_REG_PERF_DEL:
+		return 0;
+#endif
+	}
+	return 0;
+}
+
+static inline void init_trace_eprobe_call(struct trace_eprobe *ep)
+{
+	struct trace_event_call *call = trace_probe_event_call(&ep->tp);
+
+	call->flags = TRACE_EVENT_FL_EPROBE;
+	call->event.funcs = &eprobe_funcs;
+	call->class->fields_array = eprobe_fields_array;
+	call->class->reg = eprobe_register;
+}
+
+static struct trace_event_call *
+find_and_get_event(const char *system, const char *event_name)
+{
+	struct trace_event_call *tp_event;
+	const char *name;
+
+	list_for_each_entry(tp_event, &ftrace_events, list) {
+		/* Skip other probes and ftrace events */
+		if (tp_event->flags &
+		    (TRACE_EVENT_FL_IGNORE_ENABLE |
+		     TRACE_EVENT_FL_KPROBE |
+		     TRACE_EVENT_FL_UPROBE |
+		     TRACE_EVENT_FL_EPROBE))
+			continue;
+		if (!tp_event->class->system ||
+		    strcmp(system, tp_event->class->system))
+			continue;
+		name = trace_event_name(tp_event);
+		if (!name || strcmp(event_name, name))
+			continue;
+		if (!trace_event_try_get_ref(tp_event)) {
+			return NULL;
+			break;
+		}
+		return tp_event;
+		break;
+	}
+	return NULL;
+}
+
+static int trace_eprobe_tp_update_arg(struct trace_eprobe *ep, const char *argv[], int i)
+{
+	unsigned int flags = TPARG_FL_KERNEL | TPARG_FL_TPOINT;
+	int ret;
+
+	ret = traceprobe_parse_probe_arg(&ep->tp, i, argv[i], flags);
+	if (ret)
+		return ret;
+
+	if (ep->tp.args[i].code->op == FETCH_OP_TP_ARG)
+		ret = trace_eprobe_tp_arg_update(ep, i);
+
+	return ret;
+}
+
+static int __trace_eprobe_create(int argc, const char *argv[])
+{
+	/*
+	 * Argument syntax:
+	 *      e[:[GRP/]ENAME] SYSTEM.EVENT [FETCHARGS]
+	 * Fetch args:
+	 *  <name>=$<field>[:TYPE]
+	 */
+	const char *event = NULL, *group = EPROBE_EVENT_SYSTEM;
+	const char *sys_event = NULL, *sys_name = NULL;
+	struct trace_event_call *event_call;
+	struct trace_eprobe *ep = NULL;
+	char buf1[MAX_EVENT_NAME_LEN];
+	char buf2[MAX_EVENT_NAME_LEN];
+	int ret = 0;
+	int i;
+
+	if (argc < 2 || argv[0][0] != 'e')
+		return -ECANCELED;
+
+	trace_probe_log_init("event_probe", argc, argv);
+
+	event = strchr(&argv[0][1], ':');
+	if (event) {
+		event++;
+		ret = traceprobe_parse_event_name(&event, &group, buf1,
+						  event - argv[0]);
+		if (ret)
+			goto parse_error;
+	} else {
+		strscpy(buf1, argv[1], MAX_EVENT_NAME_LEN);
+		sanitize_event_name(buf1);
+		event = buf1;
+	}
+	if (!is_good_name(event) || !is_good_name(group))
+		goto parse_error;
+
+	sys_event = argv[1];
+	ret = traceprobe_parse_event_name(&sys_event, &sys_name, buf2,
+					  sys_event - argv[1]);
+	if (ret || !sys_name)
+		goto parse_error;
+	if (!is_good_name(sys_event) || !is_good_name(sys_name))
+		goto parse_error;
+
+	mutex_lock(&event_mutex);
+	event_call = find_and_get_event(sys_name, sys_event);
+	ep = alloc_event_probe(group, event, event_call, argc - 2);
+	mutex_unlock(&event_mutex);
+
+	if (IS_ERR(ep)) {
+		ret = PTR_ERR(ep);
+		/* This must return -ENOMEM, else there is a bug */
+		WARN_ON_ONCE(ret != -ENOMEM);
+		goto error;	/* We know ep is not allocated */
+	}
+
+	argc -= 2; argv += 2;
+	/* parse arguments */
+	for (i = 0; i < argc && i < MAX_TRACE_ARGS; i++) {
+		trace_probe_log_set_index(i + 2);
+		ret = trace_eprobe_tp_update_arg(ep, argv, i);
+		if (ret)
+			goto error;
+	}
+	ret = traceprobe_set_print_fmt(&ep->tp, PROBE_PRINT_EVENT);
+	if (ret < 0)
+		goto error;
+	init_trace_eprobe_call(ep);
+	mutex_lock(&event_mutex);
+	ret = trace_probe_register_event_call(&ep->tp);
+	if (ret) {
+		if (ret == -EEXIST) {
+			trace_probe_log_set_index(0);
+			trace_probe_log_err(0, EVENT_EXIST);
+		}
+		mutex_unlock(&event_mutex);
+		goto error;
+	}
+	ret = dyn_event_add(&ep->devent, &ep->tp.event->call);
+	mutex_unlock(&event_mutex);
+	return ret;
+parse_error:
+	ret = -EINVAL;
+error:
+	trace_event_probe_cleanup(ep);
+	return ret;
+}
+
+/*
+ * Register dynevent at core_initcall. This allows kernel to setup eprobe
+ * events in postcore_initcall without tracefs.
+ */
+static __init int trace_events_eprobe_init_early(void)
+{
+	int err = 0;
+
+	err = dyn_event_register(&eprobe_dyn_event_ops);
+	if (err)
+		pr_warn("Could not register eprobe_dyn_event_ops\n");
+
+	return err;
+}
+core_initcall(trace_events_eprobe_init_early);
diff --git a/kernel/trace/trace_event_perf.c b/kernel/trace/trace_event_perf.c
index 03be4435d103..6aed10e2f7ce 100644
--- a/kernel/trace/trace_event_perf.c
+++ b/kernel/trace/trace_event_perf.c
@@ -177,7 +177,7 @@ static void perf_trace_event_unreg(struct perf_event *p_event)
 		}
 	}
 out:
-	module_put(tp_event->mod);
+	trace_event_put_ref(tp_event);
 }
 
 static int perf_trace_event_open(struct perf_event *p_event)
@@ -224,10 +224,10 @@ int perf_trace_init(struct perf_event *p_event)
 	list_for_each_entry(tp_event, &ftrace_events, list) {
 		if (tp_event->event.type == event_id &&
 		    tp_event->class && tp_event->class->reg &&
-		    try_module_get(tp_event->mod)) {
+		    trace_event_try_get_ref(tp_event)) {
 			ret = perf_trace_event_init(tp_event, p_event);
 			if (ret)
-				module_put(tp_event->mod);
+				trace_event_put_ref(tp_event);
 			break;
 		}
 	}
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index 80e96989770e..1349b6de5eeb 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -2525,7 +2525,10 @@ __register_event(struct trace_event_call *call, struct module *mod)
 		return ret;
 
 	list_add(&call->list, &ftrace_events);
-	call->mod = mod;
+	if (call->flags & TRACE_EVENT_FL_DYNAMIC)
+		atomic_set(&call->refcnt, 0);
+	else
+		call->module = mod;
 
 	return 0;
 }
@@ -2839,7 +2842,9 @@ static void trace_module_remove_events(struct module *mod)
 
 	down_write(&trace_event_sem);
 	list_for_each_entry_safe(call, p, &ftrace_events, list) {
-		if (call->mod == mod)
+		if ((call->flags & TRACE_EVENT_FL_DYNAMIC) || !call->module)
+			continue;
+		if (call->module == mod)
 			__trace_remove_event_call(call);
 	}
 	up_write(&trace_event_sem);
@@ -2982,7 +2987,7 @@ struct trace_event_file *trace_get_event_file(const char *instance,
 	}
 
 	/* Don't let event modules unload while in use */
-	ret = try_module_get(file->event_call->mod);
+	ret = trace_event_try_get_ref(file->event_call);
 	if (!ret) {
 		trace_array_put(tr);
 		ret = -EBUSY;
@@ -3012,7 +3017,7 @@ EXPORT_SYMBOL_GPL(trace_get_event_file);
 void trace_put_event_file(struct trace_event_file *file)
 {
 	mutex_lock(&event_mutex);
-	module_put(file->event_call->mod);
+	trace_event_put_ref(file->event_call);
 	mutex_unlock(&event_mutex);
 
 	trace_array_put(file->tr);
@@ -3147,7 +3152,7 @@ static int free_probe_data(void *data)
 	if (!edata->ref) {
 		/* Remove the SOFT_MODE flag */
 		__ftrace_event_enable_disable(edata->file, 0, 1);
-		module_put(edata->file->event_call->mod);
+		trace_event_put_ref(edata->file->event_call);
 		kfree(edata);
 	}
 	return 0;
@@ -3280,7 +3285,7 @@ event_enable_func(struct trace_array *tr, struct ftrace_hash *hash,
 
  out_reg:
 	/* Don't let event modules unload while probe registered */
-	ret = try_module_get(file->event_call->mod);
+	ret = trace_event_try_get_ref(file->event_call);
 	if (!ret) {
 		ret = -EBUSY;
 		goto out_free;
@@ -3310,7 +3315,7 @@ event_enable_func(struct trace_array *tr, struct ftrace_hash *hash,
  out_disable:
 	__ftrace_event_enable_disable(file, 0, 1);
  out_put:
-	module_put(file->event_call->mod);
+	trace_event_put_ref(file->event_call);
  out_free:
 	kfree(data);
 	goto out;
@@ -3376,7 +3381,8 @@ void __trace_early_add_events(struct trace_array *tr)
 
 	list_for_each_entry(call, &ftrace_events, list) {
 		/* Early boot up should not have any modules loaded */
-		if (WARN_ON_ONCE(call->mod))
+		if (!(call->flags & TRACE_EVENT_FL_DYNAMIC) &&
+		    WARN_ON_ONCE(call->module))
 			continue;
 
 		ret = __trace_early_add_new_event(call, tr);
diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
index a48aa2a2875b..9d91b1c06957 100644
--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c
@@ -121,6 +121,7 @@ struct hist_field {
 	unsigned int			size;
 	unsigned int			offset;
 	unsigned int                    is_signed;
+	unsigned long			buckets;
 	const char			*type;
 	struct hist_field		*operands[HIST_FIELD_OPERANDS_MAX];
 	struct hist_trigger_data	*hist_data;
@@ -219,6 +220,27 @@ static u64 hist_field_log2(struct hist_field *hist_field,
 	return (u64) ilog2(roundup_pow_of_two(val));
 }
 
+static u64 hist_field_bucket(struct hist_field *hist_field,
+			     struct tracing_map_elt *elt,
+			     struct trace_buffer *buffer,
+			     struct ring_buffer_event *rbe,
+			     void *event)
+{
+	struct hist_field *operand = hist_field->operands[0];
+	unsigned long buckets = hist_field->buckets;
+
+	u64 val = operand->fn(operand, elt, buffer, rbe, event);
+
+	if (WARN_ON_ONCE(!buckets))
+		return val;
+
+	if (val >= LONG_MAX)
+		val = div64_ul(val, buckets);
+	else
+		val = (u64)((unsigned long)val / buckets);
+	return val * buckets;
+}
+
 static u64 hist_field_plus(struct hist_field *hist_field,
 			   struct tracing_map_elt *elt,
 			   struct trace_buffer *buffer,
@@ -318,6 +340,7 @@ enum hist_field_flags {
 	HIST_FIELD_FL_VAR_REF		= 1 << 14,
 	HIST_FIELD_FL_CPU		= 1 << 15,
 	HIST_FIELD_FL_ALIAS		= 1 << 16,
+	HIST_FIELD_FL_BUCKET		= 1 << 17,
 };
 
 struct var_defs {
@@ -1109,7 +1132,8 @@ static const char *hist_field_name(struct hist_field *field,
 	if (field->field)
 		field_name = field->field->name;
 	else if (field->flags & HIST_FIELD_FL_LOG2 ||
-		 field->flags & HIST_FIELD_FL_ALIAS)
+		 field->flags & HIST_FIELD_FL_ALIAS ||
+		 field->flags & HIST_FIELD_FL_BUCKET)
 		field_name = hist_field_name(field->operands[0], ++level);
 	else if (field->flags & HIST_FIELD_FL_CPU)
 		field_name = "common_cpu";
@@ -1396,17 +1420,17 @@ static int hist_trigger_elt_data_alloc(struct tracing_map_elt *elt)
 	struct hist_trigger_data *hist_data = elt->map->private_data;
 	unsigned int size = TASK_COMM_LEN;
 	struct hist_elt_data *elt_data;
-	struct hist_field *key_field;
+	struct hist_field *hist_field;
 	unsigned int i, n_str;
 
 	elt_data = kzalloc(sizeof(*elt_data), GFP_KERNEL);
 	if (!elt_data)
 		return -ENOMEM;
 
-	for_each_hist_key_field(i, hist_data) {
-		key_field = hist_data->fields[i];
+	for_each_hist_field(i, hist_data) {
+		hist_field = hist_data->fields[i];
 
-		if (key_field->flags & HIST_FIELD_FL_EXECNAME) {
+		if (hist_field->flags & HIST_FIELD_FL_EXECNAME) {
 			elt_data->comm = kzalloc(size, GFP_KERNEL);
 			if (!elt_data->comm) {
 				kfree(elt_data);
@@ -1470,6 +1494,8 @@ static const char *get_hist_field_flags(struct hist_field *hist_field)
 		flags_str = "syscall";
 	else if (hist_field->flags & HIST_FIELD_FL_LOG2)
 		flags_str = "log2";
+	else if (hist_field->flags & HIST_FIELD_FL_BUCKET)
+		flags_str = "buckets";
 	else if (hist_field->flags & HIST_FIELD_FL_TIMESTAMP_USECS)
 		flags_str = "usecs";
 
@@ -1590,7 +1616,9 @@ static void __destroy_hist_field(struct hist_field *hist_field)
 
 	kfree(hist_field->var.name);
 	kfree(hist_field->name);
-	kfree(hist_field->type);
+
+	/* Can likely be a const */
+	kfree_const(hist_field->type);
 
 	kfree(hist_field->system);
 	kfree(hist_field->event_name);
@@ -1647,9 +1675,7 @@ static struct hist_field *create_hist_field(struct hist_trigger_data *hist_data,
 	if (flags & HIST_FIELD_FL_HITCOUNT) {
 		hist_field->fn = hist_field_counter;
 		hist_field->size = sizeof(u64);
-		hist_field->type = kstrdup("u64", GFP_KERNEL);
-		if (!hist_field->type)
-			goto free;
+		hist_field->type = "u64";
 		goto out;
 	}
 
@@ -1658,12 +1684,13 @@ static struct hist_field *create_hist_field(struct hist_trigger_data *hist_data,
 		goto out;
 	}
 
-	if (flags & HIST_FIELD_FL_LOG2) {
-		unsigned long fl = flags & ~HIST_FIELD_FL_LOG2;
-		hist_field->fn = hist_field_log2;
+	if (flags & (HIST_FIELD_FL_LOG2 | HIST_FIELD_FL_BUCKET)) {
+		unsigned long fl = flags & ~(HIST_FIELD_FL_LOG2 | HIST_FIELD_FL_BUCKET);
+		hist_field->fn = flags & HIST_FIELD_FL_LOG2 ? hist_field_log2 :
+			hist_field_bucket;
 		hist_field->operands[0] = create_hist_field(hist_data, field, fl, NULL);
 		hist_field->size = hist_field->operands[0]->size;
-		hist_field->type = kstrdup(hist_field->operands[0]->type, GFP_KERNEL);
+		hist_field->type = kstrdup_const(hist_field->operands[0]->type, GFP_KERNEL);
 		if (!hist_field->type)
 			goto free;
 		goto out;
@@ -1672,18 +1699,14 @@ static struct hist_field *create_hist_field(struct hist_trigger_data *hist_data,
 	if (flags & HIST_FIELD_FL_TIMESTAMP) {
 		hist_field->fn = hist_field_timestamp;
 		hist_field->size = sizeof(u64);
-		hist_field->type = kstrdup("u64", GFP_KERNEL);
-		if (!hist_field->type)
-			goto free;
+		hist_field->type = "u64";
 		goto out;
 	}
 
 	if (flags & HIST_FIELD_FL_CPU) {
 		hist_field->fn = hist_field_cpu;
 		hist_field->size = sizeof(int);
-		hist_field->type = kstrdup("unsigned int", GFP_KERNEL);
-		if (!hist_field->type)
-			goto free;
+		hist_field->type = "unsigned int";
 		goto out;
 	}
 
@@ -1696,7 +1719,7 @@ static struct hist_field *create_hist_field(struct hist_trigger_data *hist_data,
 		flags |= HIST_FIELD_FL_STRING;
 
 		hist_field->size = MAX_FILTER_STR_VAL;
-		hist_field->type = kstrdup(field->type, GFP_KERNEL);
+		hist_field->type = kstrdup_const(field->type, GFP_KERNEL);
 		if (!hist_field->type)
 			goto free;
 
@@ -1709,7 +1732,7 @@ static struct hist_field *create_hist_field(struct hist_trigger_data *hist_data,
 	} else {
 		hist_field->size = field->size;
 		hist_field->is_signed = field->is_signed;
-		hist_field->type = kstrdup(field->type, GFP_KERNEL);
+		hist_field->type = kstrdup_const(field->type, GFP_KERNEL);
 		if (!hist_field->type)
 			goto free;
 
@@ -1795,7 +1818,7 @@ static int init_var_ref(struct hist_field *ref_field,
 		}
 	}
 
-	ref_field->type = kstrdup(var_field->type, GFP_KERNEL);
+	ref_field->type = kstrdup_const(var_field->type, GFP_KERNEL);
 	if (!ref_field->type) {
 		err = -ENOMEM;
 		goto free;
@@ -1953,7 +1976,7 @@ static struct hist_field *parse_var_ref(struct hist_trigger_data *hist_data,
 
 static struct ftrace_event_field *
 parse_field(struct hist_trigger_data *hist_data, struct trace_event_file *file,
-	    char *field_str, unsigned long *flags)
+	    char *field_str, unsigned long *flags, unsigned long *buckets)
 {
 	struct ftrace_event_field *field = NULL;
 	char *field_name, *modifier, *str;
@@ -1980,7 +2003,22 @@ parse_field(struct hist_trigger_data *hist_data, struct trace_event_file *file,
 			*flags |= HIST_FIELD_FL_LOG2;
 		else if (strcmp(modifier, "usecs") == 0)
 			*flags |= HIST_FIELD_FL_TIMESTAMP_USECS;
-		else {
+		else if (strncmp(modifier, "bucket", 6) == 0) {
+			int ret;
+
+			modifier += 6;
+
+			if (*modifier == 's')
+				modifier++;
+			if (*modifier != '=')
+				goto error;
+			modifier++;
+			ret = kstrtoul(modifier, 0, buckets);
+			if (ret || !(*buckets))
+				goto error;
+			*flags |= HIST_FIELD_FL_BUCKET;
+		} else {
+ error:
 			hist_err(tr, HIST_ERR_BAD_FIELD_MODIFIER, errpos(modifier));
 			field = ERR_PTR(-EINVAL);
 			goto out;
@@ -2049,6 +2087,7 @@ static struct hist_field *parse_atom(struct hist_trigger_data *hist_data,
 	char *s, *ref_system = NULL, *ref_event = NULL, *ref_var = str;
 	struct ftrace_event_field *field = NULL;
 	struct hist_field *hist_field = NULL;
+	unsigned long buckets = 0;
 	int ret = 0;
 
 	s = strchr(str, '.');
@@ -2086,7 +2125,7 @@ static struct hist_field *parse_atom(struct hist_trigger_data *hist_data,
 	} else
 		str = s;
 
-	field = parse_field(hist_data, file, str, flags);
+	field = parse_field(hist_data, file, str, flags, &buckets);
 	if (IS_ERR(field)) {
 		ret = PTR_ERR(field);
 		goto out;
@@ -2097,6 +2136,7 @@ static struct hist_field *parse_atom(struct hist_trigger_data *hist_data,
 		ret = -ENOMEM;
 		goto out;
 	}
+	hist_field->buckets = buckets;
 
 	return hist_field;
  out:
@@ -2171,7 +2211,7 @@ static struct hist_field *parse_unary(struct hist_trigger_data *hist_data,
 	expr->operands[0] = operand1;
 	expr->operator = FIELD_OP_UNARY_MINUS;
 	expr->name = expr_str(expr, 0);
-	expr->type = kstrdup(operand1->type, GFP_KERNEL);
+	expr->type = kstrdup_const(operand1->type, GFP_KERNEL);
 	if (!expr->type) {
 		ret = -ENOMEM;
 		goto free;
@@ -2311,7 +2351,7 @@ static struct hist_field *parse_expr(struct hist_trigger_data *hist_data,
 
 	expr->operator = field_op;
 	expr->name = expr_str(expr, 0);
-	expr->type = kstrdup(operand1->type, GFP_KERNEL);
+	expr->type = kstrdup_const(operand1->type, GFP_KERNEL);
 	if (!expr->type) {
 		ret = -ENOMEM;
 		goto free;
@@ -2699,10 +2739,10 @@ static struct hist_field *create_var(struct hist_trigger_data *hist_data,
 	var->var.hist_data = var->hist_data = hist_data;
 	var->size = size;
 	var->var.name = kstrdup(name, GFP_KERNEL);
-	var->type = kstrdup(type, GFP_KERNEL);
+	var->type = kstrdup_const(type, GFP_KERNEL);
 	if (!var->var.name || !var->type) {
+		kfree_const(var->type);
 		kfree(var->var.name);
-		kfree(var->type);
 		kfree(var);
 		var = ERR_PTR(-ENOMEM);
 	}
@@ -3731,6 +3771,41 @@ static int create_val_field(struct hist_trigger_data *hist_data,
 	return __create_val_field(hist_data, val_idx, file, NULL, field_str, 0);
 }
 
+static const char *no_comm = "(no comm)";
+
+static u64 hist_field_execname(struct hist_field *hist_field,
+			       struct tracing_map_elt *elt,
+			       struct trace_buffer *buffer,
+			       struct ring_buffer_event *rbe,
+			       void *event)
+{
+	struct hist_elt_data *elt_data;
+
+	if (WARN_ON_ONCE(!elt))
+		return (u64)(unsigned long)no_comm;
+
+	elt_data = elt->private_data;
+
+	if (WARN_ON_ONCE(!elt_data->comm))
+		return (u64)(unsigned long)no_comm;
+
+	return (u64)(unsigned long)(elt_data->comm);
+}
+
+/* Convert a var that points to common_pid.execname to a string */
+static void update_var_execname(struct hist_field *hist_field)
+{
+	hist_field->flags = HIST_FIELD_FL_STRING | HIST_FIELD_FL_VAR |
+		HIST_FIELD_FL_EXECNAME;
+	hist_field->size = MAX_FILTER_STR_VAL;
+	hist_field->is_signed = 0;
+
+	kfree_const(hist_field->type);
+	hist_field->type = "char[]";
+
+	hist_field->fn = hist_field_execname;
+}
+
 static int create_var_field(struct hist_trigger_data *hist_data,
 			    unsigned int val_idx,
 			    struct trace_event_file *file,
@@ -3755,6 +3830,9 @@ static int create_var_field(struct hist_trigger_data *hist_data,
 
 	ret = __create_val_field(hist_data, val_idx, file, var_name, expr_str, flags);
 
+	if (!ret && hist_data->fields[val_idx]->flags & HIST_FIELD_FL_EXECNAME)
+		update_var_execname(hist_data->fields[val_idx]);
+
 	if (!ret && hist_data->fields[val_idx]->flags & HIST_FIELD_FL_STRING)
 		hist_data->fields[val_idx]->var_str_idx = hist_data->n_var_str++;
 
@@ -4698,6 +4776,11 @@ static void hist_trigger_print_key(struct seq_file *m,
 		} else if (key_field->flags & HIST_FIELD_FL_LOG2) {
 			seq_printf(m, "%s: ~ 2^%-2llu", field_name,
 				   *(u64 *)(key + key_field->offset));
+		} else if (key_field->flags & HIST_FIELD_FL_BUCKET) {
+			unsigned long buckets = key_field->buckets;
+			uval = *(u64 *)(key + key_field->offset);
+			seq_printf(m, "%s: ~ %llu-%llu", field_name,
+				   uval, uval + buckets -1);
 		} else if (key_field->flags & HIST_FIELD_FL_STRING) {
 			seq_printf(m, "%s: %-50s", field_name,
 				   (char *)(key + key_field->offset));
@@ -5137,6 +5220,8 @@ static void hist_field_print(struct seq_file *m, struct hist_field *hist_field)
 				seq_printf(m, ".%s", flags);
 		}
 	}
+	if (hist_field->buckets)
+		seq_printf(m, "=%ld", hist_field->buckets);
 }
 
 static int event_hist_trigger_print(struct seq_file *m,
diff --git a/kernel/trace/trace_events_synth.c b/kernel/trace/trace_events_synth.c
index 9315fc03e303..d54094b7a9d7 100644
--- a/kernel/trace/trace_events_synth.c
+++ b/kernel/trace/trace_events_synth.c
@@ -1298,7 +1298,7 @@ static int __create_synth_event(const char *name, const char *raw_fields)
 	}
 	ret = register_synth_event(event);
 	if (!ret)
-		dyn_event_add(&event->devent);
+		dyn_event_add(&event->devent, &event->call);
 	else
 		free_synth_event(event);
  out:
@@ -1369,13 +1369,15 @@ static int destroy_synth_event(struct synth_event *se)
 	int ret;
 
 	if (se->ref)
-		ret = -EBUSY;
-	else {
-		ret = unregister_synth_event(se);
-		if (!ret) {
-			dyn_event_remove(&se->devent);
-			free_synth_event(se);
-		}
+		return -EBUSY;
+
+	if (trace_event_dyn_busy(&se->call))
+		return -EBUSY;
+
+	ret = unregister_synth_event(se);
+	if (!ret) {
+		dyn_event_remove(&se->devent);
+		free_synth_event(se);
 	}
 
 	return ret;
@@ -2102,6 +2104,9 @@ static int synth_event_release(struct dyn_event *ev)
 	if (event->ref)
 		return -EBUSY;
 
+	if (trace_event_dyn_busy(&event->call))
+		return -EBUSY;
+
 	ret = unregister_synth_event(event);
 	if (ret)
 		return ret;
diff --git a/kernel/trace/trace_events_trigger.c b/kernel/trace/trace_events_trigger.c
index cf84d0f6583a..3d5c07239a2a 100644
--- a/kernel/trace/trace_events_trigger.c
+++ b/kernel/trace/trace_events_trigger.c
@@ -124,6 +124,18 @@ static void *trigger_next(struct seq_file *m, void *t, loff_t *pos)
 	return seq_list_next(t, &event_file->triggers, pos);
 }
 
+static bool check_user_trigger(struct trace_event_file *file)
+{
+	struct event_trigger_data *data;
+
+	list_for_each_entry_rcu(data, &file->triggers, list) {
+		if (data->flags & EVENT_TRIGGER_FL_PROBE)
+			continue;
+		return true;
+	}
+	return false;
+}
+
 static void *trigger_start(struct seq_file *m, loff_t *pos)
 {
 	struct trace_event_file *event_file;
@@ -134,7 +146,7 @@ static void *trigger_start(struct seq_file *m, loff_t *pos)
 	if (unlikely(!event_file))
 		return ERR_PTR(-ENODEV);
 
-	if (list_empty(&event_file->triggers))
+	if (list_empty(&event_file->triggers) || !check_user_trigger(event_file))
 		return *pos == 0 ? SHOW_AVAILABLE_TRIGGERS : NULL;
 
 	return seq_list_start(&event_file->triggers, *pos);
@@ -1334,7 +1346,7 @@ void event_enable_trigger_free(struct event_trigger_ops *ops,
 	if (!data->ref) {
 		/* Remove the SOFT_MODE flag */
 		trace_event_enable_disable(enable_data->file, 0, 1);
-		module_put(enable_data->file->event_call->mod);
+		trace_event_put_ref(enable_data->file->event_call);
 		trigger_data_free(data);
 		kfree(enable_data);
 	}
@@ -1481,7 +1493,7 @@ int event_enable_trigger_func(struct event_command *cmd_ops,
 
  out_reg:
 	/* Don't let event modules unload while probe registered */
-	ret = try_module_get(event_enable_file->event_call->mod);
+	ret = trace_event_try_get_ref(event_enable_file->event_call);
 	if (!ret) {
 		ret = -EBUSY;
 		goto out_free;
@@ -1510,7 +1522,7 @@ int event_enable_trigger_func(struct event_command *cmd_ops,
  out_disable:
 	trace_event_enable_disable(event_enable_file, 0, 1);
  out_put:
-	module_put(event_enable_file->event_call->mod);
+	trace_event_put_ref(event_enable_file->event_call);
  out_free:
 	if (cmd_ops->set_filter)
 		cmd_ops->set_filter(NULL, trigger_data, NULL);
diff --git a/kernel/trace/trace_hwlat.c b/kernel/trace/trace_hwlat.c
index 14f46aae1981..1b83d75eb103 100644
--- a/kernel/trace/trace_hwlat.c
+++ b/kernel/trace/trace_hwlat.c
@@ -325,10 +325,10 @@ static void move_to_next_cpu(void)
 	if (!cpumask_equal(current_mask, current->cpus_ptr))
 		goto change_mode;
 
-	get_online_cpus();
+	cpus_read_lock();
 	cpumask_and(current_mask, cpu_online_mask, tr->tracing_cpumask);
 	next_cpu = cpumask_next(raw_smp_processor_id(), current_mask);
-	put_online_cpus();
+	cpus_read_unlock();
 
 	if (next_cpu >= nr_cpu_ids)
 		next_cpu = cpumask_first(current_mask);
@@ -398,7 +398,7 @@ static void stop_single_kthread(void)
 	struct hwlat_kthread_data *kdata = get_cpu_data();
 	struct task_struct *kthread;
 
-	get_online_cpus();
+	cpus_read_lock();
 	kthread = kdata->kthread;
 
 	if (!kthread)
@@ -408,7 +408,7 @@ static void stop_single_kthread(void)
 	kdata->kthread = NULL;
 
 out_put_cpus:
-	put_online_cpus();
+	cpus_read_unlock();
 }
 
 
@@ -425,14 +425,14 @@ static int start_single_kthread(struct trace_array *tr)
 	struct task_struct *kthread;
 	int next_cpu;
 
-	get_online_cpus();
+	cpus_read_lock();
 	if (kdata->kthread)
 		goto out_put_cpus;
 
 	kthread = kthread_create(kthread_fn, NULL, "hwlatd");
 	if (IS_ERR(kthread)) {
 		pr_err(BANNER "could not start sampling thread\n");
-		put_online_cpus();
+		cpus_read_unlock();
 		return -ENOMEM;
 	}
 
@@ -452,7 +452,7 @@ static int start_single_kthread(struct trace_array *tr)
 	wake_up_process(kthread);
 
 out_put_cpus:
-	put_online_cpus();
+	cpus_read_unlock();
 	return 0;
 }
 
@@ -479,10 +479,10 @@ static void stop_per_cpu_kthreads(void)
 {
 	unsigned int cpu;
 
-	get_online_cpus();
+	cpus_read_lock();
 	for_each_online_cpu(cpu)
 		stop_cpu_kthread(cpu);
-	put_online_cpus();
+	cpus_read_unlock();
 }
 
 /*
@@ -515,7 +515,7 @@ static void hwlat_hotplug_workfn(struct work_struct *dummy)
 
 	mutex_lock(&trace_types_lock);
 	mutex_lock(&hwlat_data.lock);
-	get_online_cpus();
+	cpus_read_lock();
 
 	if (!hwlat_busy || hwlat_data.thread_mode != MODE_PER_CPU)
 		goto out_unlock;
@@ -526,7 +526,7 @@ static void hwlat_hotplug_workfn(struct work_struct *dummy)
 	start_cpu_kthread(cpu);
 
 out_unlock:
-	put_online_cpus();
+	cpus_read_unlock();
 	mutex_unlock(&hwlat_data.lock);
 	mutex_unlock(&trace_types_lock);
 }
@@ -582,7 +582,7 @@ static int start_per_cpu_kthreads(struct trace_array *tr)
 	unsigned int cpu;
 	int retval;
 
-	get_online_cpus();
+	cpus_read_lock();
 	/*
 	 * Run only on CPUs in which hwlat is allowed to run.
 	 */
@@ -596,12 +596,12 @@ static int start_per_cpu_kthreads(struct trace_array *tr)
 		if (retval)
 			goto out_error;
 	}
-	put_online_cpus();
+	cpus_read_unlock();
 
 	return 0;
 
 out_error:
-	put_online_cpus();
+	cpus_read_unlock();
 	stop_per_cpu_kthreads();
 	return retval;
 }
diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
index ea6178cb5e33..3a64ba4bbad6 100644
--- a/kernel/trace/trace_kprobe.c
+++ b/kernel/trace/trace_kprobe.c
@@ -80,10 +80,6 @@ static struct trace_kprobe *to_trace_kprobe(struct dyn_event *ev)
 	for_each_dyn_event(dpos)		\
 		if (is_trace_kprobe(dpos) && (pos = to_trace_kprobe(dpos)))
 
-#define SIZEOF_TRACE_KPROBE(n)				\
-	(offsetof(struct trace_kprobe, tp.args) +	\
-	(sizeof(struct probe_arg) * (n)))
-
 static nokprobe_inline bool trace_kprobe_is_return(struct trace_kprobe *tk)
 {
 	return tk->rp.handler != NULL;
@@ -265,7 +261,7 @@ static struct trace_kprobe *alloc_trace_kprobe(const char *group,
 	struct trace_kprobe *tk;
 	int ret = -ENOMEM;
 
-	tk = kzalloc(SIZEOF_TRACE_KPROBE(nargs), GFP_KERNEL);
+	tk = kzalloc(struct_size(tk, tp.args, nargs), GFP_KERNEL);
 	if (!tk)
 		return ERR_PTR(ret);
 
@@ -543,6 +539,10 @@ static int unregister_trace_kprobe(struct trace_kprobe *tk)
 	if (trace_probe_is_enabled(&tk->tp))
 		return -EBUSY;
 
+	/* If there's a reference to the dynamic event */
+	if (trace_event_dyn_busy(trace_probe_event_call(&tk->tp)))
+		return -EBUSY;
+
 	/* Will fail if probe is being used by ftrace or perf */
 	if (unregister_kprobe_event(tk))
 		return -EBUSY;
@@ -618,7 +618,7 @@ static int append_trace_kprobe(struct trace_kprobe *tk, struct trace_kprobe *to)
 	if (ret)
 		trace_probe_unlink(&tk->tp);
 	else
-		dyn_event_add(&tk->devent);
+		dyn_event_add(&tk->devent, trace_probe_event_call(&tk->tp));
 
 	return ret;
 }
@@ -647,7 +647,11 @@ static int register_trace_kprobe(struct trace_kprobe *tk)
 	/* Register new event */
 	ret = register_kprobe_event(tk);
 	if (ret) {
-		pr_warn("Failed to register probe event(%d)\n", ret);
+		if (ret == -EEXIST) {
+			trace_probe_log_set_index(0);
+			trace_probe_log_err(0, EVENT_EXIST);
+		} else
+			pr_warn("Failed to register probe event(%d)\n", ret);
 		goto end;
 	}
 
@@ -661,7 +665,7 @@ static int register_trace_kprobe(struct trace_kprobe *tk)
 	if (ret < 0)
 		unregister_kprobe_event(tk);
 	else
-		dyn_event_add(&tk->devent);
+		dyn_event_add(&tk->devent, trace_probe_event_call(&tk->tp));
 
 end:
 	mutex_unlock(&event_mutex);
@@ -703,14 +707,6 @@ static struct notifier_block trace_kprobe_module_nb = {
 	.priority = 1	/* Invoked after kprobe module callback */
 };
 
-/* Convert certain expected symbols into '_' when generating event names */
-static inline void sanitize_event_name(char *name)
-{
-	while (*name++ != '\0')
-		if (*name == ':' || *name == '.')
-			*name = '_';
-}
-
 static int __trace_kprobe_create(int argc, const char *argv[])
 {
 	/*
@@ -742,6 +738,7 @@ static int __trace_kprobe_create(int argc, const char *argv[])
 	bool is_return = false;
 	char *symbol = NULL, *tmp = NULL;
 	const char *event = NULL, *group = KPROBE_EVENT_SYSTEM;
+	enum probe_print_type ptype;
 	int maxactive = 0;
 	long offset = 0;
 	void *addr = NULL;
@@ -869,20 +866,14 @@ static int __trace_kprobe_create(int argc, const char *argv[])
 
 	/* parse arguments */
 	for (i = 0; i < argc && i < MAX_TRACE_ARGS; i++) {
-		tmp = kstrdup(argv[i], GFP_KERNEL);
-		if (!tmp) {
-			ret = -ENOMEM;
-			goto error;
-		}
-
 		trace_probe_log_set_index(i + 2);
-		ret = traceprobe_parse_probe_arg(&tk->tp, i, tmp, flags);
-		kfree(tmp);
+		ret = traceprobe_parse_probe_arg(&tk->tp, i, argv[i], flags);
 		if (ret)
 			goto error;	/* This can be -ENOMEM */
 	}
 
-	ret = traceprobe_set_print_fmt(&tk->tp, is_return);
+	ptype = is_return ? PROBE_PRINT_RETURN : PROBE_PRINT_NORMAL;
+	ret = traceprobe_set_print_fmt(&tk->tp, ptype);
 	if (ret < 0)
 		goto error;
 
@@ -1330,9 +1321,10 @@ probe_mem_read(void *dest, void *src, size_t size)
 
 /* Note that we don't verify it, since the code does not come from user space */
 static int
-process_fetch_insn(struct fetch_insn *code, struct pt_regs *regs, void *dest,
+process_fetch_insn(struct fetch_insn *code, void *rec, void *dest,
 		   void *base)
 {
+	struct pt_regs *regs = rec;
 	unsigned long val;
 
 retry:
@@ -1806,6 +1798,7 @@ struct trace_event_call *
 create_local_trace_kprobe(char *func, void *addr, unsigned long offs,
 			  bool is_return)
 {
+	enum probe_print_type ptype;
 	struct trace_kprobe *tk;
 	int ret;
 	char *event;
@@ -1829,7 +1822,9 @@ create_local_trace_kprobe(char *func, void *addr, unsigned long offs,
 
 	init_trace_event_call(tk);
 
-	if (traceprobe_set_print_fmt(&tk->tp, trace_kprobe_is_return(tk)) < 0) {
+	ptype = trace_kprobe_is_return(tk) ?
+		PROBE_PRINT_RETURN : PROBE_PRINT_NORMAL;
+	if (traceprobe_set_print_fmt(&tk->tp, ptype) < 0) {
 		ret = -ENOMEM;
 		goto error;
 	}
diff --git a/kernel/trace/trace_osnoise.c b/kernel/trace/trace_osnoise.c
index b61eefe5ccf5..65b08b8e5bf8 100644
--- a/kernel/trace/trace_osnoise.c
+++ b/kernel/trace/trace_osnoise.c
@@ -1498,12 +1498,12 @@ static void stop_per_cpu_kthreads(void)
 {
 	int cpu;
 
-	get_online_cpus();
+	cpus_read_lock();
 
 	for_each_online_cpu(cpu)
 		stop_kthread(cpu);
 
-	put_online_cpus();
+	cpus_read_unlock();
 }
 
 /*
@@ -1551,7 +1551,7 @@ static int start_per_cpu_kthreads(struct trace_array *tr)
 	int retval;
 	int cpu;
 
-	get_online_cpus();
+	cpus_read_lock();
 	/*
 	 * Run only on CPUs in which trace and osnoise are allowed to run.
 	 */
@@ -1572,7 +1572,7 @@ static int start_per_cpu_kthreads(struct trace_array *tr)
 		}
 	}
 
-	put_online_cpus();
+	cpus_read_unlock();
 
 	return 0;
 }
@@ -1590,7 +1590,7 @@ static void osnoise_hotplug_workfn(struct work_struct *dummy)
 		goto out_unlock_trace;
 
 	mutex_lock(&interface_lock);
-	get_online_cpus();
+	cpus_read_lock();
 
 	if (!cpumask_test_cpu(cpu, &osnoise_cpumask))
 		goto out_unlock;
@@ -1601,7 +1601,7 @@ static void osnoise_hotplug_workfn(struct work_struct *dummy)
 	start_kthread(cpu);
 
 out_unlock:
-	put_online_cpus();
+	cpus_read_unlock();
 	mutex_unlock(&interface_lock);
 out_unlock_trace:
 	mutex_unlock(&trace_types_lock);
@@ -1743,11 +1743,11 @@ osnoise_cpus_write(struct file *filp, const char __user *ubuf, size_t count,
 	/*
 	 * osnoise_cpumask is read by CPU hotplug operations.
 	 */
-	get_online_cpus();
+	cpus_read_lock();
 
 	cpumask_copy(&osnoise_cpumask, osnoise_cpumask_new);
 
-	put_online_cpus();
+	cpus_read_unlock();
 	mutex_unlock(&interface_lock);
 
 	if (running)
diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c
index 15413ad7cef2..3ed2a3f37297 100644
--- a/kernel/trace/trace_probe.c
+++ b/kernel/trace/trace_probe.c
@@ -233,6 +233,9 @@ int traceprobe_parse_event_name(const char **pevent, const char **pgroup,
 	int len;
 
 	slash = strchr(event, '/');
+	if (!slash)
+		slash = strchr(event, '.');
+
 	if (slash) {
 		if (slash == event) {
 			trace_probe_log_err(offset, NO_GROUP_NAME);
@@ -316,6 +319,13 @@ static int parse_probe_vars(char *arg, const struct fetch_type *t,
 		code->op = FETCH_OP_ARG;
 		code->param = (unsigned int)param - 1;
 #endif
+	} else if (flags & TPARG_FL_TPOINT) {
+		if (code->data)
+			return -EFAULT;
+		code->data = kstrdup(arg, GFP_KERNEL);
+		if (!code->data)
+			return -ENOMEM;
+		code->op = FETCH_OP_TP_ARG;
 	} else
 		goto inval_var;
 
@@ -540,26 +550,34 @@ static int __parse_bitfield_probe_arg(const char *bf,
 }
 
 /* String length checking wrapper */
-static int traceprobe_parse_probe_arg_body(char *arg, ssize_t *size,
+static int traceprobe_parse_probe_arg_body(const char *argv, ssize_t *size,
 		struct probe_arg *parg, unsigned int flags, int offset)
 {
 	struct fetch_insn *code, *scode, *tmp = NULL;
 	char *t, *t2, *t3;
+	char *arg;
 	int ret, len;
 
+	arg = kstrdup(argv, GFP_KERNEL);
+	if (!arg)
+		return -ENOMEM;
+
+	ret = -EINVAL;
 	len = strlen(arg);
 	if (len > MAX_ARGSTR_LEN) {
 		trace_probe_log_err(offset, ARG_TOO_LONG);
-		return -EINVAL;
+		goto out;
 	} else if (len == 0) {
 		trace_probe_log_err(offset, NO_ARG_BODY);
-		return -EINVAL;
+		goto out;
 	}
 
+	ret = -ENOMEM;
 	parg->comm = kstrdup(arg, GFP_KERNEL);
 	if (!parg->comm)
-		return -ENOMEM;
+		goto out;
 
+	ret = -EINVAL;
 	t = strchr(arg, ':');
 	if (t) {
 		*t = '\0';
@@ -571,22 +589,22 @@ static int traceprobe_parse_probe_arg_body(char *arg, ssize_t *size,
 				offset += t2 + strlen(t2) - arg;
 				trace_probe_log_err(offset,
 						    ARRAY_NO_CLOSE);
-				return -EINVAL;
+				goto out;
 			} else if (t3[1] != '\0') {
 				trace_probe_log_err(offset + t3 + 1 - arg,
 						    BAD_ARRAY_SUFFIX);
-				return -EINVAL;
+				goto out;
 			}
 			*t3 = '\0';
 			if (kstrtouint(t2, 0, &parg->count) || !parg->count) {
 				trace_probe_log_err(offset + t2 - arg,
 						    BAD_ARRAY_NUM);
-				return -EINVAL;
+				goto out;
 			}
 			if (parg->count > MAX_ARRAY_LEN) {
 				trace_probe_log_err(offset + t2 - arg,
 						    ARRAY_TOO_BIG);
-				return -EINVAL;
+				goto out;
 			}
 		}
 	}
@@ -598,29 +616,30 @@ static int traceprobe_parse_probe_arg_body(char *arg, ssize_t *size,
 	if (strcmp(arg, "$comm") == 0 || strncmp(arg, "\\\"", 2) == 0) {
 		/* The type of $comm must be "string", and not an array. */
 		if (parg->count || (t && strcmp(t, "string")))
-			return -EINVAL;
+			goto out;
 		parg->type = find_fetch_type("string");
 	} else
 		parg->type = find_fetch_type(t);
 	if (!parg->type) {
 		trace_probe_log_err(offset + (t ? (t - arg) : 0), BAD_TYPE);
-		return -EINVAL;
+		goto out;
 	}
 	parg->offset = *size;
 	*size += parg->type->size * (parg->count ?: 1);
 
+	ret = -ENOMEM;
 	if (parg->count) {
 		len = strlen(parg->type->fmttype) + 6;
 		parg->fmt = kmalloc(len, GFP_KERNEL);
 		if (!parg->fmt)
-			return -ENOMEM;
+			goto out;
 		snprintf(parg->fmt, len, "%s[%d]", parg->type->fmttype,
 			 parg->count);
 	}
 
 	code = tmp = kcalloc(FETCH_INSN_MAX, sizeof(*code), GFP_KERNEL);
 	if (!code)
-		return -ENOMEM;
+		goto out;
 	code[FETCH_INSN_MAX - 1].op = FETCH_OP_END;
 
 	ret = parse_probe_arg(arg, parg->type, &code, &code[FETCH_INSN_MAX - 1],
@@ -628,19 +647,20 @@ static int traceprobe_parse_probe_arg_body(char *arg, ssize_t *size,
 	if (ret)
 		goto fail;
 
+	ret = -EINVAL;
 	/* Store operation */
 	if (!strcmp(parg->type->name, "string") ||
 	    !strcmp(parg->type->name, "ustring")) {
 		if (code->op != FETCH_OP_DEREF && code->op != FETCH_OP_UDEREF &&
 		    code->op != FETCH_OP_IMM && code->op != FETCH_OP_COMM &&
-		    code->op != FETCH_OP_DATA) {
+		    code->op != FETCH_OP_DATA && code->op != FETCH_OP_TP_ARG) {
 			trace_probe_log_err(offset + (t ? (t - arg) : 0),
 					    BAD_STRING);
-			ret = -EINVAL;
 			goto fail;
 		}
 		if ((code->op == FETCH_OP_IMM || code->op == FETCH_OP_COMM ||
-		     code->op == FETCH_OP_DATA) || parg->count) {
+		     code->op == FETCH_OP_DATA) || code->op == FETCH_OP_TP_ARG ||
+		     parg->count) {
 			/*
 			 * IMM, DATA and COMM is pointing actual address, those
 			 * must be kept, and if parg->count != 0, this is an
@@ -650,7 +670,6 @@ static int traceprobe_parse_probe_arg_body(char *arg, ssize_t *size,
 			code++;
 			if (code->op != FETCH_OP_NOP) {
 				trace_probe_log_err(offset, TOO_MANY_OPS);
-				ret = -EINVAL;
 				goto fail;
 			}
 		}
@@ -672,7 +691,6 @@ static int traceprobe_parse_probe_arg_body(char *arg, ssize_t *size,
 		code++;
 		if (code->op != FETCH_OP_NOP) {
 			trace_probe_log_err(offset, TOO_MANY_OPS);
-			ret = -EINVAL;
 			goto fail;
 		}
 		code->op = FETCH_OP_ST_RAW;
@@ -687,6 +705,7 @@ static int traceprobe_parse_probe_arg_body(char *arg, ssize_t *size,
 			goto fail;
 		}
 	}
+	ret = -EINVAL;
 	/* Loop(Array) operation */
 	if (parg->count) {
 		if (scode->op != FETCH_OP_ST_MEM &&
@@ -694,13 +713,11 @@ static int traceprobe_parse_probe_arg_body(char *arg, ssize_t *size,
 		    scode->op != FETCH_OP_ST_USTRING) {
 			trace_probe_log_err(offset + (t ? (t - arg) : 0),
 					    BAD_STRING);
-			ret = -EINVAL;
 			goto fail;
 		}
 		code++;
 		if (code->op != FETCH_OP_NOP) {
 			trace_probe_log_err(offset, TOO_MANY_OPS);
-			ret = -EINVAL;
 			goto fail;
 		}
 		code->op = FETCH_OP_LP_ARRAY;
@@ -709,6 +726,7 @@ static int traceprobe_parse_probe_arg_body(char *arg, ssize_t *size,
 	code++;
 	code->op = FETCH_OP_END;
 
+	ret = 0;
 	/* Shrink down the code buffer */
 	parg->code = kcalloc(code - tmp + 1, sizeof(*code), GFP_KERNEL);
 	if (!parg->code)
@@ -724,6 +742,8 @@ fail:
 				kfree(code->data);
 	}
 	kfree(tmp);
+out:
+	kfree(arg);
 
 	return ret;
 }
@@ -745,11 +765,11 @@ static int traceprobe_conflict_field_name(const char *name,
 	return 0;
 }
 
-int traceprobe_parse_probe_arg(struct trace_probe *tp, int i, char *arg,
+int traceprobe_parse_probe_arg(struct trace_probe *tp, int i, const char *arg,
 				unsigned int flags)
 {
 	struct probe_arg *parg = &tp->args[i];
-	char *body;
+	const char *body;
 
 	/* Increment count for freeing args in error case */
 	tp->nr_args++;
@@ -839,19 +859,29 @@ int traceprobe_update_arg(struct probe_arg *arg)
 /* When len=0, we just calculate the needed length */
 #define LEN_OR_ZERO (len ? len - pos : 0)
 static int __set_print_fmt(struct trace_probe *tp, char *buf, int len,
-			   bool is_return)
+			   enum probe_print_type ptype)
 {
 	struct probe_arg *parg;
 	int i, j;
 	int pos = 0;
 	const char *fmt, *arg;
 
-	if (!is_return) {
+	switch (ptype) {
+	case PROBE_PRINT_NORMAL:
 		fmt = "(%lx)";
 		arg = "REC->" FIELD_STRING_IP;
-	} else {
+		break;
+	case PROBE_PRINT_RETURN:
 		fmt = "(%lx <- %lx)";
 		arg = "REC->" FIELD_STRING_FUNC ", REC->" FIELD_STRING_RETIP;
+		break;
+	case PROBE_PRINT_EVENT:
+		fmt = "(%u)";
+		arg = "REC->" FIELD_STRING_TYPE;
+		break;
+	default:
+		WARN_ON_ONCE(1);
+		return 0;
 	}
 
 	pos += snprintf(buf + pos, LEN_OR_ZERO, "\"%s", fmt);
@@ -900,20 +930,20 @@ static int __set_print_fmt(struct trace_probe *tp, char *buf, int len,
 }
 #undef LEN_OR_ZERO
 
-int traceprobe_set_print_fmt(struct trace_probe *tp, bool is_return)
+int traceprobe_set_print_fmt(struct trace_probe *tp, enum probe_print_type ptype)
 {
 	struct trace_event_call *call = trace_probe_event_call(tp);
 	int len;
 	char *print_fmt;
 
 	/* First: called with 0 length to calculate the needed length */
-	len = __set_print_fmt(tp, NULL, 0, is_return);
+	len = __set_print_fmt(tp, NULL, 0, ptype);
 	print_fmt = kmalloc(len + 1, GFP_KERNEL);
 	if (!print_fmt)
 		return -ENOMEM;
 
 	/* Second: actually write the @print_fmt */
-	__set_print_fmt(tp, print_fmt, len + 1, is_return);
+	__set_print_fmt(tp, print_fmt, len + 1, ptype);
 	call->print_fmt = print_fmt;
 
 	return 0;
@@ -1029,11 +1059,36 @@ error:
 	return ret;
 }
 
+static struct trace_event_call *
+find_trace_event_call(const char *system, const char *event_name)
+{
+	struct trace_event_call *tp_event;
+	const char *name;
+
+	list_for_each_entry(tp_event, &ftrace_events, list) {
+		if (!tp_event->class->system ||
+		    strcmp(system, tp_event->class->system))
+			continue;
+		name = trace_event_name(tp_event);
+		if (!name || strcmp(event_name, name))
+			continue;
+		return tp_event;
+	}
+
+	return NULL;
+}
+
 int trace_probe_register_event_call(struct trace_probe *tp)
 {
 	struct trace_event_call *call = trace_probe_event_call(tp);
 	int ret;
 
+	lockdep_assert_held(&event_mutex);
+
+	if (find_trace_event_call(trace_probe_group_name(tp),
+				  trace_probe_name(tp)))
+		return -EEXIST;
+
 	ret = register_trace_event(&call->event);
 	if (!ret)
 		return -ENODEV;
diff --git a/kernel/trace/trace_probe.h b/kernel/trace/trace_probe.h
index 227d518e5ba5..99e7a5df025e 100644
--- a/kernel/trace/trace_probe.h
+++ b/kernel/trace/trace_probe.h
@@ -38,6 +38,7 @@
 #define FIELD_STRING_IP		"__probe_ip"
 #define FIELD_STRING_RETIP	"__probe_ret_ip"
 #define FIELD_STRING_FUNC	"__probe_func"
+#define FIELD_STRING_TYPE	"__probe_type"
 
 #undef DEFINE_FIELD
 #define DEFINE_FIELD(type, item, name, is_signed)			\
@@ -102,6 +103,7 @@ enum fetch_op {
 	FETCH_OP_MOD_BF,	/* Bitfield: .basesize, .lshift, .rshift */
 	// Stage 5 (loop) op
 	FETCH_OP_LP_ARRAY,	/* Array: .param = loop count */
+	FETCH_OP_TP_ARG,	/* Trace Point argument */
 	FETCH_OP_END,
 	FETCH_NOP_SYMBOL,	/* Unresolved Symbol holder */
 };
@@ -351,10 +353,11 @@ int trace_probe_create(const char *raw_command, int (*createfn)(int, const char
 #define TPARG_FL_RETURN BIT(0)
 #define TPARG_FL_KERNEL BIT(1)
 #define TPARG_FL_FENTRY BIT(2)
-#define TPARG_FL_MASK	GENMASK(2, 0)
+#define TPARG_FL_TPOINT BIT(3)
+#define TPARG_FL_MASK	GENMASK(3, 0)
 
 extern int traceprobe_parse_probe_arg(struct trace_probe *tp, int i,
-				char *arg, unsigned int flags);
+				const char *argv, unsigned int flags);
 
 extern int traceprobe_update_arg(struct probe_arg *arg);
 extern void traceprobe_free_probe_arg(struct probe_arg *arg);
@@ -363,7 +366,13 @@ extern int traceprobe_split_symbol_offset(char *symbol, long *offset);
 int traceprobe_parse_event_name(const char **pevent, const char **pgroup,
 				char *buf, int offset);
 
-extern int traceprobe_set_print_fmt(struct trace_probe *tp, bool is_return);
+enum probe_print_type {
+	PROBE_PRINT_NORMAL,
+	PROBE_PRINT_RETURN,
+	PROBE_PRINT_EVENT,
+};
+
+extern int traceprobe_set_print_fmt(struct trace_probe *tp, enum probe_print_type ptype);
 
 #ifdef CONFIG_PERF_EVENTS
 extern struct trace_event_call *
@@ -399,6 +408,7 @@ extern int traceprobe_define_arg_fields(struct trace_event_call *event_call,
 	C(NO_EVENT_NAME,	"Event name is not specified"),		\
 	C(EVENT_TOO_LONG,	"Event name is too long"),		\
 	C(BAD_EVENT_NAME,	"Event name must follow the same rules as C identifiers"), \
+	C(EVENT_EXIST,		"Given group/event name is already used by another event"), \
 	C(RETVAL_ON_PROBE,	"$retval is not available on probe"),	\
 	C(BAD_STACK_NUM,	"Invalid stack number"),		\
 	C(BAD_ARG_NUM,		"Invalid argument number"),		\
diff --git a/kernel/trace/trace_probe_tmpl.h b/kernel/trace/trace_probe_tmpl.h
index f003c5d02a3a..b3bdb8ddb862 100644
--- a/kernel/trace/trace_probe_tmpl.h
+++ b/kernel/trace/trace_probe_tmpl.h
@@ -54,7 +54,7 @@ fetch_apply_bitfield(struct fetch_insn *code, void *buf)
  * If dest is NULL, don't store result and return required dynamic data size.
  */
 static int
-process_fetch_insn(struct fetch_insn *code, struct pt_regs *regs,
+process_fetch_insn(struct fetch_insn *code, void *rec,
 		   void *dest, void *base);
 static nokprobe_inline int fetch_store_strlen(unsigned long addr);
 static nokprobe_inline int
@@ -188,7 +188,7 @@ __get_data_size(struct trace_probe *tp, struct pt_regs *regs)
 
 /* Store the value of each argument */
 static nokprobe_inline void
-store_trace_args(void *data, struct trace_probe *tp, struct pt_regs *regs,
+store_trace_args(void *data, struct trace_probe *tp, void *rec,
 		 int header_size, int maxlen)
 {
 	struct probe_arg *arg;
@@ -203,7 +203,7 @@ store_trace_args(void *data, struct trace_probe *tp, struct pt_regs *regs,
 		/* Point the dynamic data area if needed */
 		if (unlikely(arg->dynamic))
 			*dl = make_data_loc(maxlen, dyndata - base);
-		ret = process_fetch_insn(arg->code, regs, dl, base);
+		ret = process_fetch_insn(arg->code, rec, dl, base);
 		if (unlikely(ret < 0 && arg->dynamic)) {
 			*dl = make_data_loc(0, dyndata - base);
 		} else {
diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c
index 9b50869a5ddb..225ce569bf8f 100644
--- a/kernel/trace/trace_uprobe.c
+++ b/kernel/trace/trace_uprobe.c
@@ -83,10 +83,6 @@ static struct trace_uprobe *to_trace_uprobe(struct dyn_event *ev)
 	for_each_dyn_event(dpos)		\
 		if (is_trace_uprobe(dpos) && (pos = to_trace_uprobe(dpos)))
 
-#define SIZEOF_TRACE_UPROBE(n)				\
-	(offsetof(struct trace_uprobe, tp.args) +	\
-	(sizeof(struct probe_arg) * (n)))
-
 static int register_uprobe_event(struct trace_uprobe *tu);
 static int unregister_uprobe_event(struct trace_uprobe *tu);
 
@@ -217,9 +213,10 @@ static unsigned long translate_user_vaddr(unsigned long file_offset)
 
 /* Note that we don't verify it, since the code does not come from user space */
 static int
-process_fetch_insn(struct fetch_insn *code, struct pt_regs *regs, void *dest,
+process_fetch_insn(struct fetch_insn *code, void *rec, void *dest,
 		   void *base)
 {
+	struct pt_regs *regs = rec;
 	unsigned long val;
 
 	/* 1st stage: get value from context */
@@ -340,7 +337,7 @@ alloc_trace_uprobe(const char *group, const char *event, int nargs, bool is_ret)
 	struct trace_uprobe *tu;
 	int ret;
 
-	tu = kzalloc(SIZEOF_TRACE_UPROBE(nargs), GFP_KERNEL);
+	tu = kzalloc(struct_size(tu, tp.args, nargs), GFP_KERNEL);
 	if (!tu)
 		return ERR_PTR(-ENOMEM);
 
@@ -393,6 +390,10 @@ static int unregister_trace_uprobe(struct trace_uprobe *tu)
 	if (trace_probe_has_sibling(&tu->tp))
 		goto unreg;
 
+	/* If there's a reference to the dynamic event */
+	if (trace_event_dyn_busy(trace_probe_event_call(&tu->tp)))
+		return -EBUSY;
+
 	ret = unregister_uprobe_event(tu);
 	if (ret)
 		return ret;
@@ -455,7 +456,7 @@ static int append_trace_uprobe(struct trace_uprobe *tu, struct trace_uprobe *to)
 	/* Append to existing event */
 	ret = trace_probe_append(&tu->tp, &to->tp);
 	if (!ret)
-		dyn_event_add(&tu->devent);
+		dyn_event_add(&tu->devent, trace_probe_event_call(&tu->tp));
 
 	return ret;
 }
@@ -514,11 +515,15 @@ static int register_trace_uprobe(struct trace_uprobe *tu)
 
 	ret = register_uprobe_event(tu);
 	if (ret) {
-		pr_warn("Failed to register probe event(%d)\n", ret);
+		if (ret == -EEXIST) {
+			trace_probe_log_set_index(0);
+			trace_probe_log_err(0, EVENT_EXIST);
+		} else
+			pr_warn("Failed to register probe event(%d)\n", ret);
 		goto end;
 	}
 
-	dyn_event_add(&tu->devent);
+	dyn_event_add(&tu->devent, trace_probe_event_call(&tu->tp));
 
 end:
 	mutex_unlock(&event_mutex);
@@ -536,6 +541,7 @@ static int __trace_uprobe_create(int argc, const char **argv)
 	const char *event = NULL, *group = UPROBE_EVENT_SYSTEM;
 	char *arg, *filename, *rctr, *rctr_end, *tmp;
 	char buf[MAX_EVENT_NAME_LEN];
+	enum probe_print_type ptype;
 	struct path path;
 	unsigned long offset, ref_ctr_offset;
 	bool is_return = false;
@@ -680,21 +686,15 @@ static int __trace_uprobe_create(int argc, const char **argv)
 
 	/* parse arguments */
 	for (i = 0; i < argc && i < MAX_TRACE_ARGS; i++) {
-		tmp = kstrdup(argv[i], GFP_KERNEL);
-		if (!tmp) {
-			ret = -ENOMEM;
-			goto error;
-		}
-
 		trace_probe_log_set_index(i + 2);
-		ret = traceprobe_parse_probe_arg(&tu->tp, i, tmp,
+		ret = traceprobe_parse_probe_arg(&tu->tp, i, argv[i],
 					is_return ? TPARG_FL_RETURN : 0);
-		kfree(tmp);
 		if (ret)
 			goto error;
 	}
 
-	ret = traceprobe_set_print_fmt(&tu->tp, is_ret_probe(tu));
+	ptype = is_ret_probe(tu) ? PROBE_PRINT_RETURN : PROBE_PRINT_NORMAL;
+	ret = traceprobe_set_print_fmt(&tu->tp, ptype);
 	if (ret < 0)
 		goto error;
 
@@ -1585,6 +1585,7 @@ struct trace_event_call *
 create_local_trace_uprobe(char *name, unsigned long offs,
 			  unsigned long ref_ctr_offset, bool is_return)
 {
+	enum probe_print_type ptype;
 	struct trace_uprobe *tu;
 	struct path path;
 	int ret;
@@ -1619,7 +1620,8 @@ create_local_trace_uprobe(char *name, unsigned long offs,
 	tu->filename = kstrdup(name, GFP_KERNEL);
 	init_trace_event_call(tu);
 
-	if (traceprobe_set_print_fmt(&tu->tp, is_ret_probe(tu)) < 0) {
+	ptype = is_ret_probe(tu) ? PROBE_PRINT_RETURN : PROBE_PRINT_NORMAL;
+	if (traceprobe_set_print_fmt(&tu->tp, ptype) < 0) {
 		ret = -ENOMEM;
 		goto error;
 	}
diff --git a/kernel/tracepoint.c b/kernel/tracepoint.c
index efd14c79fab4..64ea283f2f86 100644
--- a/kernel/tracepoint.c
+++ b/kernel/tracepoint.c
@@ -577,7 +577,7 @@ bool trace_module_has_bad_taint(struct module *mod)
 static BLOCKING_NOTIFIER_HEAD(tracepoint_notify_list);
 
 /**
- * register_tracepoint_notifier - register tracepoint coming/going notifier
+ * register_tracepoint_module_notifier - register tracepoint coming/going notifier
  * @nb: notifier block
  *
  * Notifiers registered with this function are called on module
@@ -603,7 +603,7 @@ end:
 EXPORT_SYMBOL_GPL(register_tracepoint_module_notifier);
 
 /**
- * unregister_tracepoint_notifier - unregister tracepoint coming/going notifier
+ * unregister_tracepoint_module_notifier - unregister tracepoint coming/going notifier
  * @nb: notifier block
  *
  * The notifier block callback should expect a "struct tp_module" data
diff --git a/tools/bootconfig/scripts/bconf2ftrace.sh b/tools/bootconfig/scripts/bconf2ftrace.sh
index feb30c2c7881..850c2073433e 100755
--- a/tools/bootconfig/scripts/bconf2ftrace.sh
+++ b/tools/bootconfig/scripts/bconf2ftrace.sh
@@ -94,6 +94,92 @@ compose_synth() { # event_name branch
 	xbc_get_val $2 | while read field; do echo -n "$field; "; done
 }
 
+print_hist_array() { # prefix key
+	__sep="="
+	if xbc_has_key ${1}.${2}; then
+		echo -n ":$2"
+		xbc_get_val ${1}.${2} | while read field; do
+			echo -n "$__sep$field"; __sep=","
+		done
+	fi
+}
+
+print_hist_action_array() { # prefix key
+	__sep="("
+	echo -n ".$2"
+	xbc_get_val ${1}.${2} | while read field; do
+		echo -n "$__sep$field"; __sep=","
+	done
+	echo -n ")"
+}
+
+print_hist_one_action() { # prefix handler param
+	echo -n ":${2}("`xbc_get_val ${1}.${3}`")"
+	if xbc_has_key "${1}.trace"; then
+		print_hist_action_array ${1} "trace"
+	elif xbc_has_key "${1}.save"; then
+		print_hist_action_array ${1} "save"
+	elif xbc_has_key "${1}.snapshot"; then
+		echo -n ".snapshot()"
+	fi
+}
+
+print_hist_actions() { # prefix handler param
+	for __hdr in `xbc_subkeys ${1}.${2} 1 ".[0-9]"`; do
+		print_hist_one_action ${1}.${2}.$__hdr ${2} ${3}
+	done
+	if xbc_has_key ${1}.${2}.${3} ; then
+		print_hist_one_action ${1}.${2} ${2} ${3}
+	fi
+}
+
+print_hist_var() { # prefix varname
+	echo -n ":${2}="`xbc_get_val ${1}.var.${2} | tr -d [:space:]`
+}
+
+print_one_histogram() { # prefix
+	echo -n "hist"
+	print_hist_array $1 "keys"
+	print_hist_array $1 "values"
+	print_hist_array $1 "sort"
+	if xbc_has_key "${1}.size"; then
+		echo -n ":size="`xbc_get_val ${1}.size`
+	fi
+	if xbc_has_key "${1}.name"; then
+		echo -n ":name="`xbc_get_val ${1}.name`
+	fi
+	for __var in `xbc_subkeys "${1}.var" 1`; do
+		print_hist_var ${1} ${__var}
+	done
+	if xbc_has_key "${1}.pause"; then
+		echo -n ":pause"
+	elif xbc_has_key "${1}.continue"; then
+		echo -n ":continue"
+	elif xbc_has_key "${1}.clear"; then
+		echo -n ":clear"
+	fi
+	print_hist_actions ${1} "onmax" "var"
+	print_hist_actions ${1} "onchange" "var"
+	print_hist_actions ${1} "onmatch" "event"
+
+	if xbc_has_key "${1}.filter"; then
+		echo -n " if "`xbc_get_val ${1}.filter`
+	fi
+}
+
+setup_one_histogram() { # prefix trigger-file
+	run_cmd "echo '`print_one_histogram ${1}`' >> ${2}"
+}
+
+setup_histograms() { # prefix trigger-file
+	for __hist in `xbc_subkeys ${1} 1 ".[0-9]"`; do
+		setup_one_histogram ${1}.$__hist ${2}
+	done
+	if xbc_has_key ${1}.keys; then
+		setup_one_histogram ${1} ${2}
+	fi
+}
+
 setup_event() { # prefix group event [instance]
 	branch=$1.$2.$3
 	if [ "$4" ]; then
@@ -101,6 +187,12 @@ setup_event() { # prefix group event [instance]
 	else
 		eventdir="$TRACEFS/events/$2/$3"
 	fi
+	# group enable
+	if [ "$3" = "enable" ]; then
+		run_cmd "echo 1 > ${eventdir}"
+		return
+	fi
+
 	case $2 in
 	kprobes)
 		xbc_get_val ${branch}.probes | while read line; do
@@ -115,6 +207,8 @@ setup_event() { # prefix group event [instance]
 	set_value_of ${branch}.filter ${eventdir}/filter
 	set_array_of ${branch}.actions ${eventdir}/trigger
 
+	setup_histograms ${branch}.hist ${eventdir}/trigger
+
 	if xbc_has_key ${branch}.enable; then
 		run_cmd "echo 1 > ${eventdir}/enable"
 	fi
@@ -127,6 +221,13 @@ setup_events() { # prefix("ftrace" or "ftrace.instance.INSTANCE") [instance]
 			setup_event $prefix ${grpev%.*} ${grpev#*.} $2
 		done
 	fi
+	if xbc_has_branch ${1}.event.enable; then
+		if [ "$2" ]; then
+			run_cmd "echo 1 > $TRACEFS/instances/$2/events/enable"
+		else
+			run_cmd "echo 1 > $TRACEFS/events/enable"
+		fi
+	fi
 }
 
 size2kb() { # size[KB|MB]
diff --git a/tools/bootconfig/scripts/ftrace2bconf.sh b/tools/bootconfig/scripts/ftrace2bconf.sh
index a0c3bcc6da4f..fbaf07dc91bf 100755
--- a/tools/bootconfig/scripts/ftrace2bconf.sh
+++ b/tools/bootconfig/scripts/ftrace2bconf.sh
@@ -92,6 +92,10 @@ referred_vars() {
 	grep "^hist" $1/trigger | grep -o '$[a-zA-Z0-9]*'
 }
 
+event_is_enabled() { # enable-file
+	test -f $1 & grep -q "1" $1
+}
+
 per_event_options() { # event-dir
 	evdir=$1
 	# Check the special event which has no filter and no trigger
@@ -113,7 +117,9 @@ per_event_options() { # event-dir
 		emit_kv $PREFIX.event.$group.$event.actions += \'$action\'
 	done
 
-	# enable is not checked; this is done by set_event in the instance.
+	if [ $GROUP_ENABLED -eq 0 ] && event_is_enabled $evdir/enable; then
+		emit_kv $PREFIX.event.$group.$event.enable
+	fi
 	val=`cat $evdir/filter`
 	if [ "$val" != "none" ]; then
 		emit_kv $PREFIX.event.$group.$event.filter = "$val"
@@ -137,8 +143,19 @@ event_options() {
 		kprobe_event_options
 		synth_event_options
 	fi
+	ALL_ENABLED=0
+	if event_is_enabled $INSTANCE/events/enable; then
+		emit_kv $PREFIX.event.enable
+		ALL_ENABLED=1
+	fi
 	for group in `ls $INSTANCE/events/` ; do
 		[ ! -d $INSTANCE/events/$group ] && continue
+		GROUP_ENABLED=$ALL_ENABLED
+		if [ $ALL_ENABLED -eq 0 ] && \
+		   event_is_enabled $INSTANCE/events/$group/enable ;then
+			emit_kv $PREFIX.event.$group.enable
+			GROUP_ENABLED=1
+		fi
 		for event in `ls $INSTANCE/events/$group/` ;do
 			[ ! -d $INSTANCE/events/$group/$event ] && continue
 			per_event_options $INSTANCE/events/$group/$event
@@ -226,11 +243,6 @@ instance_options() { # [instance-name]
 		emit_kv $PREFIX.tracing_on = $val
 	fi
 
-	val=
-	for i in `cat $INSTANCE/set_event`; do
-		val="$val, $i"
-	done
-	[ "$val" ] && emit_kv $PREFIX.events = "${val#,}"
 	val=`cat $INSTANCE/current_tracer`
 	[ $val != nop ] && emit_kv $PREFIX.tracer = $val
 	if grep -qv "^#" $INSTANCE/set_ftrace_filter $INSTANCE/set_ftrace_notrace; then
diff --git a/tools/bootconfig/scripts/xbc.sh b/tools/bootconfig/scripts/xbc.sh
index b8c84e654556..1f0ebf50dd2d 100644
--- a/tools/bootconfig/scripts/xbc.sh
+++ b/tools/bootconfig/scripts/xbc.sh
@@ -49,8 +49,8 @@ xbc_has_branch() { # prefix-key
 	grep -q "^$1" $XBC_TMPFILE
 }
 
-xbc_subkeys() { # prefix-key depth
+xbc_subkeys() { # prefix-key depth [subkey-pattern]
 	__keys=`echo $1 | sed "s/\./ /g"`
 	__s=`nr_args $__keys`
-	grep "^$1" $XBC_TMPFILE | cut -d= -f1| cut -d. -f$((__s + 1))-$((__s + $2)) | uniq
+	grep "^$1$3" $XBC_TMPFILE | cut -d= -f1| cut -d. -f$((__s + 1))-$((__s + $2)) | uniq
 }
diff --git a/tools/testing/ktest/examples/bootconfigs/boottrace.bconf b/tools/testing/ktest/examples/bootconfigs/boottrace.bconf
index 9db64ec589d5..7aa706cccb3b 100644
--- a/tools/testing/ktest/examples/bootconfigs/boottrace.bconf
+++ b/tools/testing/ktest/examples/bootconfigs/boottrace.bconf
@@ -10,13 +10,23 @@ ftrace.event {
 	}
 	synthetic.initcall_latency {
 		fields = "unsigned long func", "u64 lat"
-		actions = "hist:keys=func.sym,lat:vals=lat:sort=lat"
+		hist {
+			keys = func.sym,lat
+			values = lat
+			sort = lat
+		}
 	}
-	initcall.initcall_start {
-		actions = "hist:keys=func:ts0=common_timestamp.usecs"
+	initcall.initcall_start.hist {
+		keys = func;
+		var.ts0 = common_timestamp.usecs
 	}
-	initcall.initcall_finish {
-		actions = "hist:keys=func:lat=common_timestamp.usecs-$ts0:onmatch(initcall.initcall_start).initcall_latency(func,$lat)"
+	initcall.initcall_finish.hist {
+		keys = func
+		var.lat = common_timestamp.usecs - $ts0
+		onmatch {
+			event = initcall.initcall_start
+			trace = initcall_latency, func, $lat
+		}
 	}
 }
 
diff --git a/tools/testing/ktest/examples/bootconfigs/verify-boottrace.sh b/tools/testing/ktest/examples/bootconfigs/verify-boottrace.sh
index f271940ce7fb..233e95cfcf20 100755
--- a/tools/testing/ktest/examples/bootconfigs/verify-boottrace.sh
+++ b/tools/testing/ktest/examples/bootconfigs/verify-boottrace.sh
@@ -58,7 +58,7 @@ compare_file_partial "events/synthetic/initcall_latency/enable" "0"
 compare_file_partial "events/initcall/initcall_start/trigger" "hist:keys=func:vals=hitcount:ts0=common_timestamp.usecs"
 compare_file_partial "events/initcall/initcall_start/enable" "1"
 
-compare_file_partial "events/initcall/initcall_finish/trigger" 'hist:keys=func:vals=hitcount:lat=common_timestamp.usecs-\$ts0:sort=hitcount:size=2048:clock=global:onmatch(initcall.initcall_start).initcall_latency(func,\$lat)'
+compare_file_partial "events/initcall/initcall_finish/trigger" 'hist:keys=func:vals=hitcount:lat=common_timestamp.usecs-\$ts0:sort=hitcount:size=2048:clock=global:onmatch(initcall.initcall_start).trace(initcall_latency,func,\$lat)'
 compare_file_partial "events/initcall/initcall_finish/enable" "1"
 
 compare_file "instances/foo/current_tracer" "function"
diff --git a/tools/testing/selftests/ftrace/test.d/dynevent/add_remove_eprobe.tc b/tools/testing/selftests/ftrace/test.d/dynevent/add_remove_eprobe.tc
new file mode 100644
index 000000000000..25a3da4eaa44
--- /dev/null
+++ b/tools/testing/selftests/ftrace/test.d/dynevent/add_remove_eprobe.tc
@@ -0,0 +1,40 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+# description: Generic dynamic event - add/remove eprobe events
+# requires: dynamic_events events/syscalls/sys_enter_openat "e[:[<group>/]<event>] <attached-group>.<attached-event> [<args>]":README
+
+echo 0 > events/enable
+
+clear_dynamic_events
+
+SYSTEM="syscalls"
+EVENT="sys_enter_openat"
+FIELD="filename"
+EPROBE="eprobe_open"
+
+echo "e:$EPROBE $SYSTEM/$EVENT file=+0(\$filename):ustring" >> dynamic_events
+
+grep -q "$EPROBE" dynamic_events
+test -d events/eprobes/$EPROBE
+
+echo 1 > events/eprobes/$EPROBE/enable
+ls
+echo 0 > events/eprobes/$EPROBE/enable
+
+content=`grep '^ *ls-' trace | grep 'file='`
+nocontent=`grep '^ *ls-' trace | grep 'file=' | grep -v -e '"/' -e '"."'` || true
+
+if [ -z "$content" ]; then
+	exit_fail
+fi
+
+if [ ! -z "$nocontent" ]; then
+	exit_fail
+fi
+
+echo "-:$EPROBE" >> dynamic_events
+
+! grep -q "$EPROBE" dynamic_events
+! test -d events/eprobes/$EPROBE
+
+clear_trace
diff --git a/tools/testing/selftests/ftrace/test.d/dynevent/test_duplicates.tc b/tools/testing/selftests/ftrace/test.d/dynevent/test_duplicates.tc
new file mode 100644
index 000000000000..db522577ff78
--- /dev/null
+++ b/tools/testing/selftests/ftrace/test.d/dynevent/test_duplicates.tc
@@ -0,0 +1,38 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+# description: Generic dynamic event - check if duplicate events are caught
+# requires: dynamic_events "e[:[<group>/]<event>] <attached-group>.<attached-event> [<args>]":README
+
+echo 0 > events/enable
+
+HAVE_KPROBES=0
+
+if [ -f kprobe_events ]; then
+	HAVE_KPROBES=1
+fi
+
+clear_dynamic_events
+
+# first create dynamic events for eprobes and kprobes.
+
+echo 'e:egroup/eevent syscalls/sys_enter_openat file=+0($filename):ustring' >> dynamic_events
+
+# Test eprobe for same eprobe, existing kprobe and existing event
+! echo 'e:egroup/eevent syscalls/sys_enter_openat file=+0($filename):ustring' >> dynamic_events
+! echo 'e:syscalls/sys_enter_open syscalls/sys_enter_openat file=+0($filename):ustring' >> dynamic_events
+
+if [ $HAVE_KPROBES -eq 1 ]; then
+    echo 'p:kgroup/kevent vfs_open file=+0($arg2)' >> dynamic_events
+    ! echo 'e:kgroup/kevent syscalls/sys_enter_openat file=+0($filename):ustring' >> dynamic_events
+
+# Test kprobe for same kprobe, existing eprobe and existing event
+    ! echo 'p:kgroup/kevent vfs_open file=+0($arg2)' >> dynamic_events
+    ! echo 'p:egroup/eevent vfs_open file=+0($arg2)' >> dynamic_events
+    ! echo 'p:syscalls/sys_enter_open vfs_open file=+0($arg2)' >> dynamic_events
+
+    echo '-:kgroup/kevent' >> dynamic_events
+fi
+
+echo '-:egroup/eevent' >> dynamic_events
+
+clear_trace
diff --git a/tools/testing/selftests/ftrace/test.d/functions b/tools/testing/selftests/ftrace/test.d/functions
index a6fac927ee82..000fd05e84b1 100644
--- a/tools/testing/selftests/ftrace/test.d/functions
+++ b/tools/testing/selftests/ftrace/test.d/functions
@@ -83,6 +83,27 @@ clear_synthetic_events() { # reset all current synthetic events
     done
 }
 
+clear_dynamic_events() { # reset all current dynamic events
+    again=1
+    stop=1
+    # loop mulitple times as some events require other to be removed first
+    while [ $again -eq 1 ]; do
+	stop=$((stop+1))
+	# Prevent infinite loops
+	if [ $stop -gt 10 ]; then
+	    break;
+	fi
+	again=2
+	grep -v '^#' dynamic_events|
+	while read line; do
+	    del=`echo $line | sed -e 's/^.\([^ ]*\).*/-\1/'`
+	    if ! echo "$del" >> dynamic_events; then
+		again=1
+	    fi
+	done
+    done
+}
+
 initialize_ftrace() { # Reset ftrace to initial-state
 # As the initial state, ftrace will be set to nop tracer,
 # no events, no triggers, no filters, no function filters,
@@ -93,6 +114,7 @@ initialize_ftrace() { # Reset ftrace to initial-state
     reset_events_filter
     reset_ftrace_filter
     disable_events
+    clear_dynamic_events
     [ -f set_event_pid ] && echo > set_event_pid
     [ -f set_ftrace_pid ] && echo > set_ftrace_pid
     [ -f set_ftrace_notrace ] && echo > set_ftrace_notrace
@@ -115,7 +137,7 @@ check_requires() { # Check required files and tracers
                 echo "Required tracer $t is not configured."
                 exit_unsupported
             fi
-        elif [ $r != $i ]; then
+        elif [ "$r" != "$i" ]; then
             if ! grep -Fq "$r" README ; then
                 echo "Required feature pattern \"$r\" is not in README."
                 exit_unsupported
diff --git a/tools/testing/selftests/ftrace/test.d/trigger/inter-event/trigger-synthetic-eprobe.tc b/tools/testing/selftests/ftrace/test.d/trigger/inter-event/trigger-synthetic-eprobe.tc
new file mode 100644
index 000000000000..914fe2e5d030
--- /dev/null
+++ b/tools/testing/selftests/ftrace/test.d/trigger/inter-event/trigger-synthetic-eprobe.tc
@@ -0,0 +1,53 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+# description: event trigger - test inter-event histogram trigger eprobe on synthetic event
+# requires: dynamic_events synthetic_events events/syscalls/sys_enter_openat/hist "e[:[<group>/]<event>] <attached-group>.<attached-event> [<args>]":README
+
+echo 0 > events/enable
+
+clear_dynamic_events
+
+SYSTEM="syscalls"
+START="sys_enter_openat"
+END="sys_exit_openat"
+FIELD="filename"
+SYNTH="synth_open"
+EPROBE="eprobe_open"
+
+echo "$SYNTH u64 filename; s64 ret;" > synthetic_events
+echo "hist:keys=common_pid:__arg__1=$FIELD" > events/$SYSTEM/$START/trigger
+echo "hist:keys=common_pid:filename=\$__arg__1,ret=ret:onmatch($SYSTEM.$START).trace($SYNTH,\$filename,\$ret)" > events/$SYSTEM/$END/trigger
+
+echo "e:$EPROBE synthetic/$SYNTH file=+0(\$filename):ustring ret=\$ret:s64" >> dynamic_events
+
+grep -q "$SYNTH" dynamic_events
+grep -q "$EPROBE" dynamic_events
+test -d events/synthetic/$SYNTH
+test -d events/eprobes/$EPROBE
+
+echo 1 > events/eprobes/$EPROBE/enable
+ls
+echo 0 > events/eprobes/$EPROBE/enable
+
+content=`grep '^ *ls-' trace | grep 'file='`
+nocontent=`grep '^ *ls-' trace | grep 'file=' | grep -v -e '"/' -e '"."'` || true
+
+if [ -z "$content" ]; then
+	exit_fail
+fi
+
+if [ ! -z "$nocontent" ]; then
+	exit_fail
+fi
+
+echo "-:$EPROBE" >> dynamic_events
+echo '!'"hist:keys=common_pid:filename=\$__arg__1,ret=ret:onmatch($SYSTEM.$START).trace($SYNTH,\$filename,\$ret)" > events/$SYSTEM/$END/trigger
+echo '!'"hist:keys=common_pid:__arg__1=$FIELD" > events/$SYSTEM/$START/trigger
+echo '!'"$SYNTH u64 filename; s64 ret;" >> synthetic_events
+
+! grep -q "$SYNTH" dynamic_events
+! grep -q "$EPROBE" dynamic_events
+! test -d events/synthetic/$SYNTH
+! test -d events/eprobes/$EPROBE
+
+clear_trace