trace_waitpid() loop hogs one CPU during trace-cmd record. Slow it down by making waitpid() hang for all non-stream cases (as per Steven's solution).
Signed-off-by: Vincent Stehlé <[email protected]> Cc: Steven Rostedt <[email protected]> --- On 02/04/2015 08:07 PM, Steven Rostedt wrote: > As you pointed it out, please send a new patch. Hi Steven, Thank you! Here is a v3 patch, which works for me on ARM and x86. Best regards, V. Changes since v2: - Make waitpid() hang instead of using nanosleep, as per Steven's solution. Changes since v1: - Use nanosleep and sleep_time from command line. trace-record.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/trace-record.c b/trace-record.c index 18e2e2d..3cb943d 100644 --- a/trace-record.c +++ b/trace-record.c @@ -838,7 +838,8 @@ static pid_t trace_waitpid(enum trace_type type, pid_t pid, int *status, int opt int ret; int profile = (type & TRACE_TYPE_PROFILE) == TRACE_TYPE_PROFILE; - options |= WNOHANG; + if (type & TRACE_TYPE_STREAM) + options |= WNOHANG; do { ret = waitpid(pid, status, options); -- 2.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-trace-users" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
