From 9a3dc28bb015fc730f7ffc49b7b0abf830b56b61 Mon Sep 17 00:00:00 2001 From: Arnaldo Carvalho de Melo Date: Tue, 12 Jul 2016 11:01:17 -0300 Subject: [PATCH] perf tools: Fallback to reading sysfs to get cacheline size On systems where sysconf(_SC_LEVEL1_DCACHE_LINESIZE) is not available, such as musl LIBC and Android's bionic libc. Cc: Adrian Hunter Cc: Chris Phlipot Cc: David Ahern Cc: Jiri Olsa Cc: Namhyung Kim Cc: Wang Nan Link: http://lkml.kernel.org/n/tip-772obxzby758g7m2wmzcejxz@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/perf.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/tools/perf/perf.c b/tools/perf/perf.c index f7d7dbb..4b2ff02 100644 --- a/tools/perf/perf.c +++ b/tools/perf/perf.c @@ -497,6 +497,16 @@ void pthread__unblock_sigwinch(void) pthread_sigmask(SIG_UNBLOCK, &set, NULL); } +#ifdef _SC_LEVEL1_DCACHE_LINESIZE +#define cache_line_size(cacheline_sizep) *cacheline_sizep = sysconf(_SC_LEVEL1_DCACHE_LINESIZE) +#else +static void cache_line_size(int *cacheline_sizep) +{ + if (sysfs__read_int("devices/system/cpu/cpu0/cache/index0/coherency_line_size", cacheline_sizep)) + perror("cannot determine cache line size"); +} +#endif + int main(int argc, const char **argv) { const char *cmd; @@ -509,7 +519,7 @@ int main(int argc, const char **argv) /* The page_size is placed in util object. */ page_size = sysconf(_SC_PAGE_SIZE); - cacheline_size = sysconf(_SC_LEVEL1_DCACHE_LINESIZE); + cache_line_size(&cacheline_size); if (sysctl__read_int("kernel/perf_event_max_stack", &value) == 0) sysctl_perf_event_max_stack = value; -- 2.7.4