On Thu, 6 Jul 2017 16:17:18 -0700 Joel Fernandes <[email protected]> wrote:
> Hi Steven, > > On Thu, Jul 6, 2017 at 5:59 AM, Steven Rostedt <[email protected]> wrote: > [..] > >> diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c > >> index b66a1c8805f3..27b981a46389 100644 > >> --- a/kernel/trace/trace.c > >> +++ b/kernel/trace/trace.c > >> @@ -1918,7 +1918,11 @@ static int trace_save_cmdline(struct task_struct > >> *tsk) > >> { > >> unsigned pid, idx; > >> > >> - if (!tsk->pid || unlikely(tsk->pid > PID_MAX_DEFAULT)) > >> + /* treat recording of idle task as a success */ > >> + if (!tsk->pid) > >> + return 1; > >> + > >> + if (unlikely(tsk->pid > PID_MAX_DEFAULT)) > >> return 0; > > > > Make this a separate patch. This should go to stable. > > Actually I am not sure if this should be marked for stable since > before we were doing: > tracing_record_cmdline(prev); > tracing_record_cmdline(next); > in probe_sched_switch, thus even if prev was the idle task, it would > still goto record the next. Ah right. I wasn't sure when that change was made. I should have looked deeper into it. > > IMO it becomes an issue only with the new stuff where we record > cmdline for prev and next in the same call > (tracing_record_taskinfo_sched_switch). Anyway I already broke it up > into a different patch and sent it out. Let me know if anything else > needs to be done here, thanks. OK, I'll take a look at it tomorrow. Thanks, -- Steve
