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-rw-r--r--Documentation/trace/events-nmi.txt43
-rw-r--r--Documentation/trace/events-power.txt31
-rw-r--r--Documentation/trace/events.txt15
-rw-r--r--Documentation/trace/ftrace.txt17
-rw-r--r--Documentation/trace/tracepoints.txt19
5 files changed, 118 insertions, 7 deletions
diff --git a/Documentation/trace/events-nmi.txt b/Documentation/trace/events-nmi.txt
new file mode 100644
index 000000000000..c03c8c89f08d
--- /dev/null
+++ b/Documentation/trace/events-nmi.txt
@@ -0,0 +1,43 @@
+NMI Trace Events
+
+These events normally show up here:
+
+ /sys/kernel/debug/tracing/events/nmi
+
+--
+
+nmi_handler:
+
+You might want to use this tracepoint if you suspect that your
+NMI handlers are hogging large amounts of CPU time. The kernel
+will warn if it sees long-running handlers:
+
+ INFO: NMI handler took too long to run: 9.207 msecs
+
+and this tracepoint will allow you to drill down and get some
+more details.
+
+Let's say you suspect that perf_event_nmi_handler() is causing
+you some problems and you only want to trace that handler
+specifically. You need to find its address:
+
+ $ grep perf_event_nmi_handler /proc/kallsyms
+ ffffffff81625600 t perf_event_nmi_handler
+
+Let's also say you are only interested in when that function is
+really hogging a lot of CPU time, like a millisecond at a time.
+Note that the kernel's output is in milliseconds, but the input
+to the filter is in nanoseconds! You can filter on 'delta_ns':
+
+cd /sys/kernel/debug/tracing/events/nmi/nmi_handler
+echo 'handler==0xffffffff81625600 && delta_ns>1000000' > filter
+echo 1 > enable
+
+Your output would then look like:
+
+$ cat /sys/kernel/debug/tracing/trace_pipe
+<idle>-0 [000] d.h3 505.397558: nmi_handler: perf_event_nmi_handler() delta_ns: 3236765 handled: 1
+<idle>-0 [000] d.h3 505.805893: nmi_handler: perf_event_nmi_handler() delta_ns: 3174234 handled: 1
+<idle>-0 [000] d.h3 506.158206: nmi_handler: perf_event_nmi_handler() delta_ns: 3084642 handled: 1
+<idle>-0 [000] d.h3 506.334346: nmi_handler: perf_event_nmi_handler() delta_ns: 3080351 handled: 1
+
diff --git a/Documentation/trace/events-power.txt b/Documentation/trace/events-power.txt
index e1498ff8cf94..3bd33b8dc7c4 100644
--- a/Documentation/trace/events-power.txt
+++ b/Documentation/trace/events-power.txt
@@ -63,3 +63,34 @@ power_domain_target "%s state=%lu cpu_id=%lu"
The first parameter gives the power domain name (e.g. "mpu_pwrdm").
The second parameter is the power domain target state.
+4. PM QoS events
+================
+The PM QoS events are used for QoS add/update/remove request and for
+target/flags update.
+
+pm_qos_add_request "pm_qos_class=%s value=%d"
+pm_qos_update_request "pm_qos_class=%s value=%d"
+pm_qos_remove_request "pm_qos_class=%s value=%d"
+pm_qos_update_request_timeout "pm_qos_class=%s value=%d, timeout_us=%ld"
+
+The first parameter gives the QoS class name (e.g. "CPU_DMA_LATENCY").
+The second parameter is value to be added/updated/removed.
+The third parameter is timeout value in usec.
+
+pm_qos_update_target "action=%s prev_value=%d curr_value=%d"
+pm_qos_update_flags "action=%s prev_value=0x%x curr_value=0x%x"
+
+The first parameter gives the QoS action name (e.g. "ADD_REQ").
+The second parameter is the previous QoS value.
+The third parameter is the current QoS value to update.
+
+And, there are also events used for device PM QoS add/update/remove request.
+
+dev_pm_qos_add_request "device=%s type=%s new_value=%d"
+dev_pm_qos_update_request "device=%s type=%s new_value=%d"
+dev_pm_qos_remove_request "device=%s type=%s new_value=%d"
+
+The first parameter gives the device name which tries to add/update/remove
+QoS requests.
+The second parameter gives the request type (e.g. "DEV_PM_QOS_LATENCY").
+The third parameter is value to be added/updated/removed.
diff --git a/Documentation/trace/events.txt b/Documentation/trace/events.txt
index bb24c2a0e870..37732a220d33 100644
--- a/Documentation/trace/events.txt
+++ b/Documentation/trace/events.txt
@@ -183,13 +183,22 @@ The relational-operators depend on the type of the field being tested:
The operators available for numeric fields are:
-==, !=, <, <=, >, >=
+==, !=, <, <=, >, >=, &
And for string fields they are:
-==, !=
+==, !=, ~
-Currently, only exact string matches are supported.
+The glob (~) only accepts a wild card character (*) at the start and or
+end of the string. For example:
+
+ prev_comm ~ "*sh"
+ prev_comm ~ "sh*"
+ prev_comm ~ "*sh*"
+
+But does not allow for it to be within the string:
+
+ prev_comm ~ "ba*sh" <-- is invalid
5.2 Setting filters
-------------------
diff --git a/Documentation/trace/ftrace.txt b/Documentation/trace/ftrace.txt
index bfe8c29b1f1d..ea2d35d64d26 100644
--- a/Documentation/trace/ftrace.txt
+++ b/Documentation/trace/ftrace.txt
@@ -735,7 +735,7 @@ Here are the available options:
function as well as the function being traced.
print-parent:
- bash-4000 [01] 1477.606694: simple_strtoul <-strict_strtoul
+ bash-4000 [01] 1477.606694: simple_strtoul <-kstrtoul
noprint-parent:
bash-4000 [01] 1477.606694: simple_strtoul
@@ -759,7 +759,7 @@ Here are the available options:
latency-format option is enabled.
bash 4000 1 0 00000000 00010a95 [58127d26] 1720.415ms \
- (+0.000ms): simple_strtoul (strict_strtoul)
+ (+0.000ms): simple_strtoul (kstrtoul)
raw - This will display raw numbers. This option is best for
use with user applications that can translate the raw
@@ -2430,6 +2430,19 @@ The following commands are supported:
echo '!schedule:disable_event:sched:sched_switch' > \
set_ftrace_filter
+- dump
+ When the function is hit, it will dump the contents of the ftrace
+ ring buffer to the console. This is useful if you need to debug
+ something, and want to dump the trace when a certain function
+ is hit. Perhaps its a function that is called before a tripple
+ fault happens and does not allow you to get a regular dump.
+
+- cpudump
+ When the function is hit, it will dump the contents of the ftrace
+ ring buffer for the current CPU to the console. Unlike the "dump"
+ command, it only prints out the contents of the ring buffer for the
+ CPU that executed the function that triggered the dump.
+
trace_pipe
----------
diff --git a/Documentation/trace/tracepoints.txt b/Documentation/trace/tracepoints.txt
index da49437d5aeb..ac4170dd0f24 100644
--- a/Documentation/trace/tracepoints.txt
+++ b/Documentation/trace/tracepoints.txt
@@ -40,7 +40,13 @@ Two elements are required for tracepoints :
In order to use tracepoints, you should include linux/tracepoint.h.
-In include/trace/subsys.h :
+In include/trace/events/subsys.h :
+
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM subsys
+
+#if !defined(_TRACE_SUBSYS_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _TRACE_SUBSYS_H
#include <linux/tracepoint.h>
@@ -48,10 +54,16 @@ DECLARE_TRACE(subsys_eventname,
TP_PROTO(int firstarg, struct task_struct *p),
TP_ARGS(firstarg, p));
+#endif /* _TRACE_SUBSYS_H */
+
+/* This part must be outside protection */
+#include <trace/define_trace.h>
+
In subsys/file.c (where the tracing statement must be added) :
-#include <trace/subsys.h>
+#include <trace/events/subsys.h>
+#define CREATE_TRACE_POINTS
DEFINE_TRACE(subsys_eventname);
void somefct(void)
@@ -72,6 +84,9 @@ Where :
- TP_ARGS(firstarg, p) are the parameters names, same as found in the
prototype.
+- if you use the header in multiple source files, #define CREATE_TRACE_POINTS
+ should appear only in one source file.
+
Connecting a function (probe) to a tracepoint is done by providing a
probe (function to call) for the specific tracepoint through
register_trace_subsys_eventname(). Removing a probe is done through