Merge tag 'trace-v5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing updates from Steven Rostedt:
 "New tracing features:

   - New PERMANENT flag to ftrace_ops when attaching a callback to a
     function.

     As /proc/sys/kernel/ftrace_enabled when set to zero will disable
     all attached callbacks in ftrace, this has a detrimental impact on
     live kernel tracing, as it disables all that it patched. If a
     ftrace_ops is registered to ftrace with the PERMANENT flag set, it
     will prevent ftrace_enabled from being disabled, and if
     ftrace_enabled is already disabled, it will prevent a ftrace_ops
     with PREMANENT flag set from being registered.

   - New register_ftrace_direct().

     As eBPF would like to register its own trampolines to be called by
     the ftrace nop locations directly, without going through the ftrace
     trampoline, this function has been added. This allows for eBPF
     trampolines to live along side of ftrace, perf, kprobe and live
     patching. It also utilizes the ftrace enabled_functions file that
     keeps track of functions that have been modified in the kernel, to
     allow for security auditing.

   - Allow for kernel internal use of ftrace instances.

     Subsystems in the kernel can now create and destroy their own
     tracing instances which allows them to have their own tracing
     buffer, and be able to record events without worrying about other
     users from writing over their data.

   - New seq_buf_hex_dump() that lets users use the hex_dump() in their
     seq_buf usage.

   - Notifications now added to tracing_max_latency to allow user space
     to know when a new max latency is hit by one of the latency
     tracers.

   - Wider spread use of generic compare operations for use of bsearch
     and friends.

   - More synthetic event fields may be defined (32 up from 16)

   - Use of xarray for architectures with sparse system calls, for the
     system call trace events.

  This along with small clean ups and fixes"

* tag 'trace-v5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (51 commits)
  tracing: Enable syscall optimization for MIPS
  tracing: Use xarray for syscall trace events
  tracing: Sample module to demonstrate kernel access to Ftrace instances.
  tracing: Adding new functions for kernel access to Ftrace instances
  tracing: Fix Kconfig indentation
  ring-buffer: Fix typos in function ring_buffer_producer
  ftrace: Use BIT() macro
  ftrace: Return ENOTSUPP when DYNAMIC_FTRACE_WITH_DIRECT_CALLS is not configured
  ftrace: Rename ftrace_graph_stub to ftrace_stub_graph
  ftrace: Add a helper function to modify_ftrace_direct() to allow arch optimization
  ftrace: Add helper find_direct_entry() to consolidate code
  ftrace: Add another check for match in register_ftrace_direct()
  ftrace: Fix accounting bug with direct->count in register_ftrace_direct()
  ftrace/selftests: Fix spelling mistake "wakeing" -> "waking"
  tracing: Increase SYNTH_FIELDS_MAX for synthetic_events
  ftrace/samples: Add a sample module that implements modify_ftrace_direct()
  ftrace: Add modify_ftrace_direct()
  tracing: Add missing "inline" in stub function of latency_fsnotify()
  tracing: Remove stray tab in TRACE_EVAL_MAP_FILE's help text
  tracing: Use seq_buf_hex_dump() to dump buffers
  ...

1 files changed, 17 insertions, 9 deletions

diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig
index 382628b9b759..cdf5afa87f65 100644
--- a/kernel/trace/Kconfig
+++ b/kernel/trace/Kconfig
@@ -33,6 +33,9 @@ config HAVE_DYNAMIC_FTRACE
 config HAVE_DYNAMIC_FTRACE_WITH_REGS
 	bool
 
+config HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS
+	bool
+
 config HAVE_FTRACE_MCOUNT_RECORD
 	bool
 	help
@@ -76,7 +79,7 @@ config FTRACE_NMI_ENTER
 
 config EVENT_TRACING
 	select CONTEXT_SWITCH_TRACER
-        select GLOB
+	select GLOB
 	bool
 
 config CONTEXT_SWITCH_TRACER
@@ -307,7 +310,7 @@ config TRACER_SNAPSHOT
 	      cat snapshot
 
 config TRACER_SNAPSHOT_PER_CPU_SWAP
-        bool "Allow snapshot to swap per CPU"
+	bool "Allow snapshot to swap per CPU"
 	depends on TRACER_SNAPSHOT
 	select RING_BUFFER_ALLOW_SWAP
 	help
@@ -556,6 +559,11 @@ config DYNAMIC_FTRACE_WITH_REGS
 	depends on DYNAMIC_FTRACE
 	depends on HAVE_DYNAMIC_FTRACE_WITH_REGS
 
+config DYNAMIC_FTRACE_WITH_DIRECT_CALLS
+	def_bool y
+	depends on DYNAMIC_FTRACE
+	depends on HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS
+
 config FUNCTION_PROFILER
 	bool "Kernel function profiler"
 	depends on FUNCTION_TRACER
@@ -674,7 +682,7 @@ config MMIOTRACE_TEST
 	  Say N, unless you absolutely know what you are doing.
 
 config TRACEPOINT_BENCHMARK
-        bool "Add tracepoint that benchmarks tracepoints"
+	bool "Add tracepoint that benchmarks tracepoints"
 	help
 	 This option creates the tracepoint "benchmark:benchmark_event".
 	 When the tracepoint is enabled, it kicks off a kernel thread that
@@ -723,7 +731,7 @@ config RING_BUFFER_STARTUP_TEST
        bool "Ring buffer startup self test"
        depends on RING_BUFFER
        help
-         Run a simple self test on the ring buffer on boot up. Late in the
+	 Run a simple self test on the ring buffer on boot up. Late in the
 	 kernel boot sequence, the test will start that kicks off
 	 a thread per cpu. Each thread will write various size events
 	 into the ring buffer. Another thread is created to send IPIs
@@ -751,9 +759,9 @@ config PREEMPTIRQ_DELAY_TEST
 	  configurable delay. The module busy waits for the duration of the
 	  critical section.
 
-	  For example, the following invocation forces a one-time irq-disabled
-	  critical section for 500us:
-	  modprobe preemptirq_delay_test test_mode=irq delay=500000
+	  For example, the following invocation generates a burst of three
+	  irq-disabled critical sections for 500us:
+	  modprobe preemptirq_delay_test test_mode=irq delay=500 burst_size=3
 
 	  If unsure, say N
 
@@ -762,7 +770,7 @@ config TRACE_EVAL_MAP_FILE
        depends on TRACING
        help
 	The "print fmt" of the trace events will show the enum/sizeof names
-	instead	of their values. This can cause problems for user space tools
+	instead of their values. This can cause problems for user space tools
 	that use this string to parse the raw data as user space does not know
 	how to convert the string to its value.
 
@@ -783,7 +791,7 @@ config TRACE_EVAL_MAP_FILE
 	they are needed for the "eval_map" file. Enabling this option will
 	increase the memory footprint of the running kernel.
 
-	If unsure, say N
+	If unsure, say N.
 
 config GCOV_PROFILE_FTRACE
 	bool "Enable GCOV profiling on ftrace subsystem"