Commit-ID: f988e71bc6220d8b404dbd43c0e0962e30305795
Gitweb: https://git.kernel.org/tip/f988e71bc6220d8b404dbd43c0e0962e30305795
Author: Kan Liang <kan.liang@xxxxxxxxx>
AuthorDate: Fri, 29 Sep 2017 07:47:53 -0700
Committer: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
CommitDate: Tue, 3 Oct 2017 09:27:36 -0300
perf tools: Lock to protect comm_str rb tree
Add comm_str_lock to protect comm_str rb tree.
The lock is only needed for multithreaded code, so using mutex wrappers
provided by perf tool.
Signed-off-by: Kan Liang <kan.liang@xxxxxxxxx>
Acked-by: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Cc: Alexei Starovoitov <ast@xxxxxxxxxx>
Cc: Andi Kleen <ak@xxxxxxxxxxxxxxx>
Cc: He Kuang <hekuang@xxxxxxxxxx>
Cc: Lukasz Odzioba <lukasz.odzioba@xxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Wang Nan <wangnan0@xxxxxxxxxx>
Link: http://lkml.kernel.org/r/1506696477-146932-3-git-send-email-kan.liang@xxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
tools/perf/util/comm.c | 18 +++++++++++++++++-
1 file changed, 17 insertions(+), 1 deletion(-)
diff --git a/tools/perf/util/comm.c b/tools/perf/util/comm.c
index 7bc981b..756a9c1 100644
--- a/tools/perf/util/comm.c
+++ b/tools/perf/util/comm.c
@@ -5,6 +5,7 @@
#include <stdio.h>
#include <string.h>
#include <linux/refcount.h>
+#include "rwsem.h"
struct comm_str {
char *str;
@@ -14,6 +15,7 @@ struct comm_str {
/* Should perhaps be moved to struct machine */
static struct rb_root comm_str_root;
+static struct rw_semaphore comm_str_lock = {.lock = PTHREAD_RWLOCK_INITIALIZER,};
static struct comm_str *comm_str__get(struct comm_str *cs)
{
@@ -25,7 +27,9 @@ static struct comm_str *comm_str__get(struct comm_str *cs)
static void comm_str__put(struct comm_str *cs)
{
if (cs && refcount_dec_and_test(&cs->refcnt)) {
+ down_write(&comm_str_lock);
rb_erase(&cs->rb_node, &comm_str_root);
+ up_write(&comm_str_lock);
zfree(&cs->str);
free(cs);
}
@@ -50,7 +54,8 @@ static struct comm_str *comm_str__alloc(const char *str)
return cs;
}
-static struct comm_str *comm_str__findnew(const char *str, struct rb_root *root)
+static
+struct comm_str *__comm_str__findnew(const char *str, struct rb_root *root)
{
struct rb_node **p = &root->rb_node;
struct rb_node *parent = NULL;
@@ -81,6 +86,17 @@ static struct comm_str *comm_str__findnew(const char *str, struct rb_root *root)
return new;
}
+static struct comm_str *comm_str__findnew(const char *str, struct rb_root *root)
+{
+ struct comm_str *cs;
+
+ down_write(&comm_str_lock);
+ cs = __comm_str__findnew(str, root);
+ up_write(&comm_str_lock);
+
+ return cs;
+}
+
struct comm *comm__new(const char *str, u64 timestamp, bool exec)
{
struct comm *comm = zalloc(sizeof(*comm));
--
To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
|