From 188bb5e2ce112463428994f91291e5df6fc05521 Mon Sep 17 00:00:00 2001 From: Adrian Hunter Date: Fri, 25 Sep 2015 16:15:46 +0300 Subject: [PATCH] perf report: Make max_stack value allow for synthesized callchains perf report has an option (--max-stack) to set the maximum stack depth when processing callchains. The option defaults to the hard-coded maximum definition PERF_MAX_STACK_DEPTH which is 127. The intention of the option is to allow the user to reduce the processing time by reducing the amount of the callchain that is processed. It is also possible, when processing instruction traces, to synthesize callchains. Synthesized callchains do not have the kernel size limitation and are whatever size the user requests, although validation presently prevents the user requested a value greater that 1024. The default value is 16. To allow for synthesized callchains, make the max_stack value at least the same size as the synthesized callchain size. Signed-off-by: Adrian Hunter Cc: Jiri Olsa Link: http://lkml.kernel.org/r/1443186956-18718-16-git-send-email-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/builtin-report.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/tools/perf/builtin-report.c b/tools/perf/builtin-report.c index e94e5c7155af..37c9f5125887 100644 --- a/tools/perf/builtin-report.c +++ b/tools/perf/builtin-report.c @@ -809,6 +809,10 @@ int cmd_report(int argc, const char **argv, const char *prefix __maybe_unused) if (report.inverted_callchain) callchain_param.order = ORDER_CALLER; + if (itrace_synth_opts.callchain && + (int)itrace_synth_opts.callchain_sz > report.max_stack) + report.max_stack = itrace_synth_opts.callchain_sz; + if (!input_name || !strlen(input_name)) { if (!fstat(STDIN_FILENO, &st) && S_ISFIFO(st.st_mode)) input_name = "-";