Commit-ID: 151ee834cc946fa159ee406c62b4d5ce1ebd7115 Gitweb: http://git.kernel.org/tip/151ee834cc946fa159ee406c62b4d5ce1ebd7115 Author: Namhyung Kim <namhy...@kernel.org> AuthorDate: Fri, 11 Dec 2015 11:56:54 +0900 Committer: Arnaldo Carvalho de Melo <a...@redhat.com> CommitDate: Fri, 11 Dec 2015 08:34:49 -0300
perf top: Access hists->lock only if needed The perf_top__record_precise_ip() releases and regrabs the he->hists->lock because it can sleep if there's an error. But it should be done conditionally as it slows down the fast path. Signed-off-by: Namhyung Kim <namhy...@kernel.org> Cc: David Ahern <dsah...@gmail.com> Cc: Jiri Olsa <jo...@redhat.com> Cc: Peter Zijlstra <a.p.zijls...@chello.nl> Link: http://lkml.kernel.org/r/1449802616-16170-2-git-send-email-namhy...@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <a...@redhat.com> --- tools/perf/builtin-top.c | 28 +++++++++++++++------------- 1 file changed, 15 insertions(+), 13 deletions(-) diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c index 3b0978e..586798a 100644 --- a/tools/perf/builtin-top.c +++ b/tools/perf/builtin-top.c @@ -194,21 +194,23 @@ static void perf_top__record_precise_ip(struct perf_top *top, pthread_mutex_unlock(¬es->lock); - /* - * This function is now called with he->hists->lock held. - * Release it before going to sleep. - */ - pthread_mutex_unlock(&he->hists->lock); + if (unlikely(err)) { + /* + * This function is now called with he->hists->lock held. + * Release it before going to sleep. + */ + pthread_mutex_unlock(&he->hists->lock); + + if (err == -ERANGE && !he->ms.map->erange_warned) + ui__warn_map_erange(he->ms.map, sym, ip); + else if (err == -ENOMEM) { + pr_err("Not enough memory for annotating '%s' symbol!\n", + sym->name); + sleep(1); + } - if (err == -ERANGE && !he->ms.map->erange_warned) - ui__warn_map_erange(he->ms.map, sym, ip); - else if (err == -ENOMEM) { - pr_err("Not enough memory for annotating '%s' symbol!\n", - sym->name); - sleep(1); + pthread_mutex_lock(&he->hists->lock); } - - pthread_mutex_lock(&he->hists->lock); } static void perf_top__show_details(struct perf_top *top) -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
