From: Arnaldo Carvalho de Melo <a...@redhat.com> It is not read as commonly as 'page_size', so it makes sense to read it lazily, caching its value when it is first read.
Less files open unconditionally at startup. Cc: Adrian Hunter <adrian.hun...@intel.com> Cc: David Ahern <dsah...@gmail.com> Cc: Jiri Olsa <jo...@kernel.org> Cc: Namhyung Kim <namhy...@kernel.org> Cc: Wang Nan <wangn...@huawei.com> Link: https://lkml.kernel.org/n/tip-35xhrq91u94uc1djtclek...@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <a...@redhat.com> --- tools/perf/perf.c | 11 ----------- tools/perf/util/sort.c | 4 ++-- tools/perf/util/sort.h | 4 ++-- tools/perf/util/util.c | 21 ++++++++++++++++++++- tools/perf/util/util.h | 2 +- 5 files changed, 25 insertions(+), 17 deletions(-) diff --git a/tools/perf/perf.c b/tools/perf/perf.c index d5a0878de816..cefd8f74630c 100644 --- a/tools/perf/perf.c +++ b/tools/perf/perf.c @@ -421,16 +421,6 @@ 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)) - pr_debug("cannot determine cache line size"); -} -#endif - int main(int argc, const char **argv) { int err; @@ -444,7 +434,6 @@ int main(int argc, const char **argv) /* The page_size is placed in util object. */ page_size = sysconf(_SC_PAGE_SIZE); - cache_line_size(&cacheline_size); if (sysctl__read_int("kernel/perf_event_max_stack", &value) == 0) sysctl_perf_event_max_stack = value; diff --git a/tools/perf/util/sort.c b/tools/perf/util/sort.c index e65903a695a6..4058ade352a5 100644 --- a/tools/perf/util/sort.c +++ b/tools/perf/util/sort.c @@ -2582,7 +2582,7 @@ int sort_dimension__add(struct perf_hpp_list *list, const char *tok, if (sort__mode != SORT_MODE__MEMORY) return -EINVAL; - if (sd->entry == &sort_mem_dcacheline && cacheline_size == 0) + if (sd->entry == &sort_mem_dcacheline && cacheline_size() == 0) return -EINVAL; if (sd->entry == &sort_mem_daddr_sym) @@ -2628,7 +2628,7 @@ static int setup_sort_list(struct perf_hpp_list *list, char *str, if (*tok) { ret = sort_dimension__add(list, tok, evlist, level); if (ret == -EINVAL) { - if (!cacheline_size && !strncasecmp(tok, "dcacheline", strlen(tok))) + if (!cacheline_size() && !strncasecmp(tok, "dcacheline", strlen(tok))) pr_err("The \"dcacheline\" --sort key needs to know the cacheline size and it couldn't be determined on this system"); else pr_err("Invalid --sort key: `%s'", tok); diff --git a/tools/perf/util/sort.h b/tools/perf/util/sort.h index 035b62e2c60b..9e6896293bbd 100644 --- a/tools/perf/util/sort.h +++ b/tools/perf/util/sort.h @@ -186,13 +186,13 @@ static inline float hist_entry__get_percent_limit(struct hist_entry *he) static inline u64 cl_address(u64 address) { /* return the cacheline of the address */ - return (address & ~(cacheline_size - 1)); + return (address & ~(cacheline_size() - 1)); } static inline u64 cl_offset(u64 address) { /* return the cacheline of the address */ - return (address & (cacheline_size - 1)); + return (address & (cacheline_size() - 1)); } enum sort_mode { diff --git a/tools/perf/util/util.c b/tools/perf/util/util.c index 1019bbc5dbd8..99ab52165680 100644 --- a/tools/perf/util/util.c +++ b/tools/perf/util/util.c @@ -38,7 +38,26 @@ void perf_set_multithreaded(void) } unsigned int page_size; -int cacheline_size; + +#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)) + pr_debug("cannot determine cache line size"); +} +#endif + +int cacheline_size(void) +{ + static int size; + + if (!size) + cache_line_size(&size); + + return size; +} int sysctl_perf_event_max_stack = PERF_MAX_STACK_DEPTH; int sysctl_perf_event_max_contexts_per_stack = PERF_MAX_CONTEXTS_PER_STACK; diff --git a/tools/perf/util/util.h b/tools/perf/util/util.h index c9626c206208..74d21dfe0d29 100644 --- a/tools/perf/util/util.h +++ b/tools/perf/util/util.h @@ -43,7 +43,7 @@ size_t hex_width(u64 v); int hex2u64(const char *ptr, u64 *val); extern unsigned int page_size; -extern int cacheline_size; +int __pure cacheline_size(void); int fetch_kernel_version(unsigned int *puint, char *str, size_t str_sz); -- 2.14.3
