Commit b303e7c1 authored Apr 04, 2016 by Peter Zijlstra Committed by Ingo Molnar Apr 23, 2016

perf/core: Make sysctl_perf_cpu_time_max_percent conform to documentation



Markus reported that 0 should also disable the throttling we per
Documentation/sysctl/kernel.txt.

Reported-by: Markus Trippelsdorf <markus@trippelsdorf.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Fixes: 91a612ee ("perf/core: Fix dynamic interrupt throttle")
Signed-off-by: Ingo Molnar <mingo@kernel.org>

parent e1089602

kernel/events/core.c

+2 −1

Original line number	Diff line number	Diff line
		@@ -412,7 +412,8 @@ int perf_cpu_time_max_percent_handler(struct ctl_table *table, int write,
		if (ret \|\| !write)
		return ret;

		if (sysctl_perf_cpu_time_max_percent == 100) {
		if (sysctl_perf_cpu_time_max_percent == 100 \|\|
		sysctl_perf_cpu_time_max_percent == 0) {
		printk(KERN_WARNING
		"perf: Dynamic interrupt throttling disabled, can hang your system!\n");
		WRITE_ONCE(perf_sample_allowed_ns, 0);