From: Namhyung Kim <namhyung@kernel.org>
To: Arnaldo Carvalho de Melo <acme@kernel.org>, Jiri Olsa <jolsa@redhat.com>
Cc: LKML <linux-kernel@vger.kernel.org>,
Krister Johansen <kjlx@templeofstupid.com>,
Hari Bathini <hbathini@linux.vnet.ibm.com>
Subject: [PATCH 1/3] perf tools: Protect reading thread's namespace
Date: Wed, 22 May 2019 14:32:48 +0900 [thread overview]
Message-ID: <20190522053250.207156-2-namhyung@kernel.org> (raw)
In-Reply-To: <20190522053250.207156-1-namhyung@kernel.org>
It seems that the current code lacks holding the namespace lock in
thread__namespaces(). Otherwise it can see inconsistent results.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
---
tools/perf/util/thread.c | 15 +++++++++++++--
1 file changed, 13 insertions(+), 2 deletions(-)
diff --git a/tools/perf/util/thread.c b/tools/perf/util/thread.c
index 403045a2bbea..b413ba5b9835 100644
--- a/tools/perf/util/thread.c
+++ b/tools/perf/util/thread.c
@@ -133,7 +133,7 @@ void thread__put(struct thread *thread)
}
}
-struct namespaces *thread__namespaces(const struct thread *thread)
+static struct namespaces *__thread__namespaces(const struct thread *thread)
{
if (list_empty(&thread->namespaces_list))
return NULL;
@@ -141,10 +141,21 @@ struct namespaces *thread__namespaces(const struct thread *thread)
return list_first_entry(&thread->namespaces_list, struct namespaces, list);
}
+struct namespaces *thread__namespaces(const struct thread *thread)
+{
+ struct namespaces *ns;
+
+ down_read((struct rw_semaphore *)&thread->namespaces_lock);
+ ns = __thread__namespaces(thread);
+ up_read((struct rw_semaphore *)&thread->namespaces_lock);
+
+ return ns;
+}
+
static int __thread__set_namespaces(struct thread *thread, u64 timestamp,
struct namespaces_event *event)
{
- struct namespaces *new, *curr = thread__namespaces(thread);
+ struct namespaces *new, *curr = __thread__namespaces(thread);
new = namespaces__new(event);
if (!new)
--
2.21.0.1020.gf2820cf01a-goog
next prev parent reply other threads:[~2019-05-22 5:33 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-05-22 5:32 [PATCH 0/3] perf tools: Assorted fixes and cleanups for namespace events Namhyung Kim
2019-05-22 5:32 ` Namhyung Kim [this message]
2019-05-22 13:18 ` [PATCH 1/3] perf tools: Protect reading thread's namespace Arnaldo Carvalho de Melo
2019-05-23 2:36 ` Namhyung Kim
2019-05-27 6:11 ` [PATCH 4/3] perf tools: Remove const from thread read accessors Namhyung Kim
2019-05-27 14:15 ` Arnaldo Carvalho de Melo
2019-05-30 8:07 ` [tip:perf/core] " tip-bot for Namhyung Kim
2019-05-28 21:27 ` [tip:perf/urgent] perf namespace: Protect reading thread's namespace tip-bot for Namhyung Kim
2019-05-22 5:32 ` [PATCH 2/3] perf tools: Add missing swap ops for namespace events Namhyung Kim
2019-05-22 13:23 ` Arnaldo Carvalho de Melo
2019-05-28 21:28 ` [tip:perf/urgent] perf session: " tip-bot for Namhyung Kim
2019-05-22 5:32 ` [PATCH 3/3] perf top: Enable --namespaces option Namhyung Kim
2019-05-22 13:24 ` Arnaldo Carvalho de Melo
2019-05-23 2:42 ` Namhyung Kim
2019-05-30 8:06 ` [tip:perf/core] perf top: Add " tip-bot for Namhyung Kim
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