diff options
author | Kan Liang | 2017-09-29 16:47:53 +0200 |
---|---|---|
committer | Arnaldo Carvalho de Melo | 2017-10-03 14:27:36 +0200 |
commit | f988e71bc6220d8b404dbd43c0e0962e30305795 (patch) | |
tree | 4f554e04a5480e14b7342934339a995d42af23dc /tools | |
parent | perf tools: Lock to protect namespaces and comm list (diff) | |
download | kernel-qcow2-linux-f988e71bc6220d8b404dbd43c0e0962e30305795.tar.gz kernel-qcow2-linux-f988e71bc6220d8b404dbd43c0e0962e30305795.tar.xz kernel-qcow2-linux-f988e71bc6220d8b404dbd43c0e0962e30305795.zip |
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@intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Lukasz Odzioba <lukasz.odzioba@intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1506696477-146932-3-git-send-email-kan.liang@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools')
-rw-r--r-- | tools/perf/util/comm.c | 18 |
1 files changed, 17 insertions, 1 deletions
diff --git a/tools/perf/util/comm.c b/tools/perf/util/comm.c index 7bc981b6bf29..756a9c14efbb 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)); |