From 4cb93446c587d56e2a54f4f83113daba2c0b6dee Mon Sep 17 00:00:00 2001 From: Arnaldo Carvalho de Melo Date: Wed, 27 Apr 2016 10:16:24 -0300 Subject: perf tools: Set the maximum allowed stack from /proc/sys/kernel/perf_event_max_stack There is an upper limit to what tooling considers a valid callchain, and it was tied to the hardcoded value in the kernel, PERF_MAX_STACK_DEPTH (127), now that this can be tuned via a sysctl, make it read it and use that as the upper limit, falling back to PERF_MAX_STACK_DEPTH for kernels where this sysctl isn't present. Cc: Adrian Hunter Cc: Brendan Gregg Cc: David Ahern Cc: Frederic Weisbecker Cc: Jiri Olsa Cc: Milian Wolff Cc: Namhyung Kim Cc: Wang Nan Link: http://lkml.kernel.org/n/tip-yjqsd30nnkogvj5oyx9ghir9@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/scripting-engines/trace-event-perl.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'tools/perf/util/scripting-engines') diff --git a/tools/perf/util/scripting-engines/trace-event-perl.c b/tools/perf/util/scripting-engines/trace-event-perl.c index ae1cebc..62c7f69 100644 --- a/tools/perf/util/scripting-engines/trace-event-perl.c +++ b/tools/perf/util/scripting-engines/trace-event-perl.c @@ -265,7 +265,7 @@ static SV *perl_process_callchain(struct perf_sample *sample, if (thread__resolve_callchain(al->thread, &callchain_cursor, evsel, sample, NULL, NULL, - PERF_MAX_STACK_DEPTH) != 0) { + sysctl_perf_event_max_stack) != 0) { pr_err("Failed to resolve callchain. Skipping\n"); goto exit; } -- cgit v1.1