BMC/Intel-BMC/linux.git/kernel/trace/trace_sched_wakeup.c, branch dev-4.3

sched: Introduce the 'trace_sched_waking' tracepoint

2015-08-03T10:21:22+00:00

Mathieu reported that since 317f394160e9 ("sched: Move the second half of ttwu() to the remote cpu") trace_sched_wakeup() can happen out of context of the waker. This is a problem when you want to analyse wakeup paths because it is now very hard to correlate the wakeup event to whoever issued the wakeup. OTOH trace_sched_wakeup() is issued at the point where we set p->state = TASK_RUNNING, which is right were we hand the task off to the scheduler, so this is an important point when looking at scheduling behaviour, up to here its been the wakeup path everything hereafter is due to scheduler policy. To bridge this gap, introduce a second tracepoint: trace_sched_waking. It is guaranteed to be called in the waker context. Reported-by: Mathieu Desnoyers Signed-off-by: Peter Zijlstra (Intel) Cc: Francis Giraldeau Cc: Linus Torvalds Cc: Mike Galbraith Cc: Peter Zijlstra Cc: Steven Rostedt Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/20150609091336.GQ3644@twins.programming.kicks-ass.net Signed-off-by: Ingo Molnar

tracing: Rename ftrace_event_{call,class} to trace_event_{call,class}

2015-05-13T18:06:10+00:00

The name "ftrace" really refers to the function hook infrastructure. It is not about the trace_events. The structures ftrace_event_call and ftrace_event_class have nothing to do with the function hooks, and are really trace_event structures. Rename ftrace_event_* to trace_event_*. Signed-off-by: Steven Rostedt

tracing: Remove unneeded includes of debugfs.h and fs.h

2015-01-22T16:19:48+00:00

The creation of tracing files and directories is for the most part encapsulated in helper functions in trace.c. Other files do not need to include debugfs.h or fs.h, as they may have needed to in the past. Remove them from the files that do not need them. Signed-off-by: Steven Rostedt

tracing: Move tracing_sched_{switch,wakeup}() into wakeup tracer

2014-11-11T17:43:15+00:00

The only code that references tracing_sched_switch_trace() and tracing_sched_wakeup_trace() is the wakeup latency tracer. Those two functions use to belong to the sched_switch tracer which has long been removed. These functions were left behind because the wakeup latency tracer used them. But since the wakeup latency tracer is the only one to use them, they should be static functions inside that code. Signed-off-by: Steven Rostedt

tracing: Remove mock up poll wait function

2014-04-30T12:40:05+00:00

Now that the ring buffer has a built in way to wake up readers when there's data, using irq_work such that it is safe to do it in any context. But it was still using the old "poor man's" wait polling that checks every 1/10 of a second to see if it should wake up a waiter. This makes the latency for a wake up excruciatingly long. No need to do that anymore. Completely remove the different wait_poll types from the tracers and have them all use the default one now. Reported-by: Johannes Berg Signed-off-by: Steven Rostedt

tracing: Allow wakeup tracers to be used by instances

2014-04-21T17:59:28+00:00

The wakeup and wakeup_rt tracers can now be used by instances. But they may only be used by one instance at a time (including the top level directory). This allows multiple tracers to run while the wakeup tracer is running simultaneously. Signed-off-by: Steven Rostedt

tracing: Move tracing_max_latency into trace_array

2014-04-21T17:59:26+00:00

In preparation for letting the latency tracers be used by instances, remove the global tracing_max_latency variable and add a max_latency field to the trace_array that the latency tracers will now use. Signed-off-by: Steven Rostedt

ftrace: Remove global function list and call function directly

2014-04-21T17:59:25+00:00

Instead of having a list of global functions that are called, as only one global function is allow to be enabled at a time, there's no reason to have a list. Instead, simply have all the users of the global ops, use the global ops directly, instead of registering their own ftrace_ops. Just switch what function is used before enabling the function tracer. This removes a lot of code as well as the complexity involved with it. Signed-off-by: Steven Rostedt

tracing: Pass trace_array to flag_changed callback

2014-02-20T17:13:08+00:00

As options (flags) may affect instances instead of being global the flag_changed() callbacks need to receive the trace_array descriptor of the instance they will be modifying. Signed-off-by: Steven Rostedt

tracing: Pass trace_array to set_flag callback

2014-02-20T17:13:07+00:00

As options (flags) may affect instances instead of being global the set_flag() callbacks need to receive the trace_array descriptor of the instance they will be modifying. Signed-off-by: Steven Rostedt