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| author | Joel Fernandes <joelaf@google.com> | 2017-06-27 04:01:55 +0200 |
|---|---|---|
| committer | Steven Rostedt (VMware) <rostedt@goodmis.org> | 2017-06-27 19:30:28 +0200 |
| commit | d914ba37d7145acb9fd3bb23075c2d56e5a44eb6 (patch) | |
| tree | edb1e6c1bfa0f0a92e13e9f891be524a31b23cea /kernel/trace/trace.h | |
| parent | ftrace: Decrement count for dyn_ftrace_total_info file (diff) | |
| download | linux-d914ba37d7145acb9fd3bb23075c2d56e5a44eb6.tar.xz linux-d914ba37d7145acb9fd3bb23075c2d56e5a44eb6.zip | |
tracing: Add support for recording tgid of tasks
Inorder to support recording of tgid, the following changes are made:
* Introduce a new API (tracing_record_taskinfo) to additionally record the tgid
along with the task's comm at the same time. This has has the benefit of not
setting trace_cmdline_save before all the information for a task is saved.
* Add a new API tracing_record_taskinfo_sched_switch to record task information
for 2 tasks at a time (previous and next) and use it from sched_switch probe.
* Preserve the old API (tracing_record_cmdline) and create it as a wrapper
around the new one so that existing callers aren't affected.
* Reuse the existing sched_switch and sched_wakeup probes to record tgid
information and add a new option 'record-tgid' to enable recording of tgid
When record-tgid option isn't enabled to being with, we take care to make sure
that there's isn't memory or runtime overhead.
Link: http://lkml.kernel.org/r/20170627020155.5139-1-joelaf@google.com
Cc: kernel-team@android.com
Cc: Ingo Molnar <mingo@redhat.com>
Tested-by: Michael Sartain <mikesart@gmail.com>
Signed-off-by: Joel Fernandes <joelaf@google.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Diffstat (limited to 'kernel/trace/trace.h')
| -rw-r--r-- | kernel/trace/trace.h | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index 13823951e42b..6ade1c55cc3a 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -640,6 +640,9 @@ void set_graph_array(struct trace_array *tr); void tracing_start_cmdline_record(void); void tracing_stop_cmdline_record(void); +void tracing_start_tgid_record(void); +void tracing_stop_tgid_record(void); + int register_tracer(struct tracer *type); int is_tracing_stopped(void); @@ -700,6 +703,7 @@ static inline void __trace_stack(struct trace_array *tr, unsigned long flags, extern u64 ftrace_now(int cpu); extern void trace_find_cmdline(int pid, char comm[]); +extern int trace_find_tgid(int pid); extern void trace_event_follow_fork(struct trace_array *tr, bool enable); #ifdef CONFIG_DYNAMIC_FTRACE @@ -1124,6 +1128,7 @@ extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf, C(CONTEXT_INFO, "context-info"), /* Print pid/cpu/time */ \ C(LATENCY_FMT, "latency-format"), \ C(RECORD_CMD, "record-cmd"), \ + C(RECORD_TGID, "record-tgid"), \ C(OVERWRITE, "overwrite"), \ C(STOP_ON_FREE, "disable_on_free"), \ C(IRQ_INFO, "irq-info"), \ @@ -1440,6 +1445,8 @@ struct ftrace_event_field * trace_find_event_field(struct trace_event_call *call, char *name); extern void trace_event_enable_cmd_record(bool enable); +extern void trace_event_enable_tgid_record(bool enable); + extern int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr); extern int event_trace_del_tracer(struct trace_array *tr); |