user/sven/linux.git/tools/lib/traceevent/plugin_sched_switch.c, branch v4.4.294

tools lib traceevent: Fix prev/next_prio for deadline tasks

2017-08-07T02:19:46Z

[ Upstream commit 074859184d770824f4437dca716bdeb625ae8b1c ] Currently, the sched:sched_switch tracepoint reports deadline tasks with priority -1. But when reading the trace via perf script I've got the following output: # ./d & # (d is a deadline task, see [1]) # perf record -e sched:sched_switch -a sleep 1 # perf script ... swapper 0 [000] 2146.962441: sched:sched_switch: swapper/0:0 [120] R ==> d:2593 [4294967295] d 2593 [000] 2146.972472: sched:sched_switch: d:2593 [4294967295] R ==> g:2590 [4294967295] The task d reports the wrong priority [4294967295]. This happens because the "int prio" is stored in an unsigned long long val. Although it is set as a %lld, as int is shorter than unsigned long long, trace_seq_printf prints it as a positive number. The fix is just to cast the val as an int, and print it as a %d, as in the sched:sched_switch tracepoint's "format". The output with the fix is: # ./d & # perf record -e sched:sched_switch -a sleep 1 # perf script ... swapper 0 [000] 4306.374037: sched:sched_switch: swapper/0:0 [120] R ==> d:10941 [-1] d 10941 [000] 4306.383823: sched:sched_switch: d:10941 [-1] R ==> swapper/0:0 [120] [1] d.c --- #include #include #include #include #include struct sched_attr { __u32 size, sched_policy; __u64 sched_flags; __s32 sched_nice; __u32 sched_priority; __u64 sched_runtime, sched_deadline, sched_period; }; int sched_setattr(pid_t pid, const struct sched_attr *attr, unsigned int flags) { return syscall(__NR_sched_setattr, pid, attr, flags); } int main(void) { struct sched_attr attr = { .size = sizeof(attr), .sched_policy = SCHED_DEADLINE, /* This creates a 10ms/30ms reservation */ .sched_runtime = 10 * 1000 * 1000, .sched_period = attr.sched_deadline = 30 * 1000 * 1000, }; if (sched_setattr(0, &attr, 0) < 0) { perror("sched_setattr"); return -1; } for(;;); } --- Committer notes: Got the program from the provided URL, http://bristot.me/lkml/d.c, trimmed it and included in the cset log above, so that we have everything needed to test it in one place. Signed-off-by: Daniel Bristot de Oliveira Acked-by: Steven Rostedt Tested-by: Arnaldo Carvalho de Melo Cc: Alexander Shishkin Cc: Daniel Bristot de Oliveira Cc: Jiri Olsa Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/866ef75bcebf670ae91c6a96daa63597ba981f0d.1483443552.git.bristot@redhat.com Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

tools lib traceevent: Unregister handler when sched_switch plugin is unloaded

2014-01-16T19:26:25Z

The event handlers should be unregistered when the plugin is unloaded otherwise they'll try to access invalid memory. Signed-off-by: Namhyung Kim Reviewed-by: Jiri Olsa Acked-by: Steven Rostedt Cc: Frederic Weisbecker Cc: Ingo Molnar Cc: Jiri Olsa Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Steven Rostedt Link: http://lkml.kernel.org/r/1389839478-5887-8-git-send-email-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo

tools lib traceevent: Add sched_switch plugin

2013-12-04T18:31:11Z

Backporting sched_switch plugin. Backported from Steven Rostedt's trace-cmd repo (HEAD 0f2c2fb): git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/trace-cmd.git This plugin adds fields resolving for sched:sched_switch tracepoint event. The diff of 'perf script' output generated by old and new code: (data was generated by 'perf record -e sched:sched_switch -a') --- script.sched_switch.old +++ script.sched_switch.new - perf 577 [002] 30965.311852: sched:sched_switch: prev_comm=perf prev_pid=577 prev_prio=120 prev_state=S ==> next_comm=swapper/2 next_pid=0 next_prio=120 + perf 577 [002] 30965.311852: sched:sched_switch: perf:577 [120] S ==> swapper/2:0 [120] Signed-off-by: Jiri Olsa Cc: Corey Ashford Cc: David Ahern Cc: Frederic Weisbecker Cc: Ingo Molnar Cc: Namhyung Kim Cc: Paul Mackerras Cc: Peter Zijlstra Cc: Steven Rostedt Link: http://lkml.kernel.org/r/1386076182-14484-18-git-send-email-jolsa@redhat.com Signed-off-by: Steven Rostedt Signed-off-by: Arnaldo Carvalho de Melo