From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751604AbdLBExO (ORCPT ); Fri, 1 Dec 2017 23:53:14 -0500 Received: from mga01.intel.com ([192.55.52.88]:10285 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751373AbdLBExN (ORCPT ); Fri, 1 Dec 2017 23:53:13 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.45,348,1508828400"; d="scan'208";a="1250968343" Subject: Re: [PATCH v5 10/12] perf util: Reuse thread_map__new_by_uid to enumerate threads from /proc To: Arnaldo Carvalho de Melo Cc: jolsa@kernel.org, peterz@infradead.org, mingo@redhat.com, alexander.shishkin@linux.intel.com, Linux-kernel@vger.kernel.org, ak@linux.intel.com, kan.liang@intel.com, yao.jin@intel.com References: <1512125856-22056-1-git-send-email-yao.jin@linux.intel.com> <1512125856-22056-11-git-send-email-yao.jin@linux.intel.com> <20171201144425.GZ3298@kernel.org> <20171201150234.GA3298@kernel.org> From: "Jin, Yao" Message-ID: Date: Sat, 2 Dec 2017 12:53:09 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:52.0) Gecko/20100101 Thunderbird/52.4.0 MIME-Version: 1.0 In-Reply-To: <20171201150234.GA3298@kernel.org> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 12/1/2017 11:02 PM, Arnaldo Carvalho de Melo wrote: > Em Fri, Dec 01, 2017 at 11:44:25AM -0300, Arnaldo Carvalho de Melo escreveu: >> Em Fri, Dec 01, 2017 at 06:57:34PM +0800, Jin Yao escreveu: >>> Perf already has a function thread_map__new_by_uid() which can >>> enumerate all threads from /proc by uid. >>> >>> This patch creates a static function enumerate_threads() which >>> reuses the common code in thread_map__new_by_uid() to enumerate >>> threads from /proc. >>> >>> The enumerate_threads() is shared by thread_map__new_by_uid() >>> and a new function thread_map__new_threads(). >>> >>> The new function thread_map__new_threads() is called to enumerate >>> all threads from /proc. >>> >>> Signed-off-by: Jin Yao >>> --- >>> tools/perf/tests/thread-map.c | 2 +- >>> tools/perf/util/evlist.c | 3 ++- >>> tools/perf/util/thread_map.c | 19 ++++++++++++++++--- >>> tools/perf/util/thread_map.h | 3 ++- >>> 4 files changed, 21 insertions(+), 6 deletions(-) >>> >>> diff --git a/tools/perf/tests/thread-map.c b/tools/perf/tests/thread-map.c >>> index dbcb6a1..4de1939 100644 >>> --- a/tools/perf/tests/thread-map.c >>> +++ b/tools/perf/tests/thread-map.c >>> @@ -105,7 +105,7 @@ int test__thread_map_remove(struct test *test __maybe_unused, int subtest __mayb >>> TEST_ASSERT_VAL("failed to allocate map string", >>> asprintf(&str, "%d,%d", getpid(), getppid()) >= 0); >>> >>> - threads = thread_map__new_str(str, NULL, 0); >>> + threads = thread_map__new_str(str, NULL, 0, false); >>> >>> TEST_ASSERT_VAL("failed to allocate thread_map", >>> threads); >>> diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c >>> index 199bb82..05b8f2b 100644 >>> --- a/tools/perf/util/evlist.c >>> +++ b/tools/perf/util/evlist.c >>> @@ -1102,7 +1102,8 @@ int perf_evlist__create_maps(struct perf_evlist *evlist, struct target *target) >>> struct cpu_map *cpus; >>> struct thread_map *threads; >>> >>> - threads = thread_map__new_str(target->pid, target->tid, target->uid); >>> + threads = thread_map__new_str(target->pid, target->tid, target->uid, >>> + target->per_thread); >>> >>> if (!threads) >>> return -1; >>> diff --git a/tools/perf/util/thread_map.c b/tools/perf/util/thread_map.c >>> index be0d5a7..5672268 100644 >>> --- a/tools/perf/util/thread_map.c >>> +++ b/tools/perf/util/thread_map.c >>> @@ -92,7 +92,7 @@ struct thread_map *thread_map__new_by_tid(pid_t tid) >>> return threads; >>> } >>> >>> -struct thread_map *thread_map__new_by_uid(uid_t uid) >>> +static struct thread_map *enumerate_threads(uid_t uid) >>> { >>> DIR *proc; >>> int max_threads = 32, items, i; >>> @@ -124,7 +124,7 @@ struct thread_map *thread_map__new_by_uid(uid_t uid) >>> if (stat(path, &st) != 0) >>> continue; >> >> Look, for the case where you want all threads enumerated you will incur >> the above stat() cost for all of them and will not use it at all... >> >> And new_threads() seems vague, I'm using the ter used by 'perf record' >> for system wide sampling, see the patch below: >> > > The one below even compiles, I'll push what I merged already and we can > continue from there: > > [acme@jouet linux]$ git log --oneline -3 > 5cc4fc8994eb (HEAD -> perf/core) perf thread_map: Add method to map all threads in the system > 9e49c22bd4d8 perf stat: Add rbtree node_delete op > 1c92e3226546 perf rblist: Create rblist__exit() function > [acme@jouet linux]$ > > Yes we can continue from these commits. I just pull the branch perf/core from https://git.kernel.org/pub/scm/linux/kernel/git/acme/linux.git, but it looks the new commits have not been synced. Maybe I will wait to next week to see if the new commits are synced and then continue the work. Thanks Jin Yao > commit 5cc4fc8994eb3f3af1950f3b726b6008900c7b06 > Author: Arnaldo Carvalho de Melo > Date: Fri Dec 1 11:44:30 2017 -0300 > > perf thread_map: Add method to map all threads in the system > > Reusing the thread_map__new_by_uid() proc scanning already in place to > return a map with all threads in the system. > > Based-on-a-patch-by: Jin Yao > Acked-by: Jiri Olsa > Cc: Alexander Shishkin > Cc: Andi Kleen > Cc: Kan Liang > Cc: Peter Zijlstra > Link: https://lkml.kernel.org/n/tip-khh28q0wwqbqtrk32bfe07hd@git.kernel.org > Signed-off-by: Arnaldo Carvalho de Melo > > diff --git a/tools/perf/util/thread_map.c b/tools/perf/util/thread_map.c > index be0d5a736dea..2b653853eec2 100644 > --- a/tools/perf/util/thread_map.c > +++ b/tools/perf/util/thread_map.c > @@ -92,7 +92,7 @@ struct thread_map *thread_map__new_by_tid(pid_t tid) > return threads; > } > > -struct thread_map *thread_map__new_by_uid(uid_t uid) > +static struct thread_map *__thread_map__new_all_cpus(uid_t uid) > { > DIR *proc; > int max_threads = 32, items, i; > @@ -113,7 +113,6 @@ struct thread_map *thread_map__new_by_uid(uid_t uid) > while ((dirent = readdir(proc)) != NULL) { > char *end; > bool grow = false; > - struct stat st; > pid_t pid = strtol(dirent->d_name, &end, 10); > > if (*end) /* only interested in proper numerical dirents */ > @@ -121,11 +120,12 @@ struct thread_map *thread_map__new_by_uid(uid_t uid) > > snprintf(path, sizeof(path), "/proc/%s", dirent->d_name); > > - if (stat(path, &st) != 0) > - continue; > + if (uid != UINT_MAX) { > + struct stat st; > > - if (st.st_uid != uid) > - continue; > + if (stat(path, &st) != 0 || st.st_uid != uid) > + continue; > + } > > snprintf(path, sizeof(path), "/proc/%d/task", pid); > items = scandir(path, &namelist, filter, NULL); > @@ -178,6 +178,16 @@ struct thread_map *thread_map__new_by_uid(uid_t uid) > goto out_closedir; > } > > +struct thread_map *thread_map__new_all_cpus(void) > +{ > + return __thread_map__new_all_cpus(UINT_MAX); > +} > + > +struct thread_map *thread_map__new_by_uid(uid_t uid) > +{ > + return __thread_map__new_all_cpus(uid); > +} > + > struct thread_map *thread_map__new(pid_t pid, pid_t tid, uid_t uid) > { > if (pid != -1) > diff --git a/tools/perf/util/thread_map.h b/tools/perf/util/thread_map.h > index f15803985435..07a765fb22bb 100644 > --- a/tools/perf/util/thread_map.h > +++ b/tools/perf/util/thread_map.h > @@ -23,6 +23,7 @@ struct thread_map *thread_map__new_dummy(void); > struct thread_map *thread_map__new_by_pid(pid_t pid); > struct thread_map *thread_map__new_by_tid(pid_t tid); > struct thread_map *thread_map__new_by_uid(uid_t uid); > +struct thread_map *thread_map__new_all_cpus(void); > struct thread_map *thread_map__new(pid_t pid, pid_t tid, uid_t uid); > struct thread_map *thread_map__new_event(struct thread_map_event *event); > >