From: "Steven Rostedt (VMware)" rostedt@goodmis.org
stable inclusion from linux-4.19.196 commit 04e7a7c95027e72bba8973e1c4b9b4a1b29f7a0c
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commit 4fdd595e4f9a1ff6d93ec702eaecae451cfc6591 upstream.
A while ago, when the "trace" file was opened, tracing was stopped, and code was added to stop recording the comms to saved_cmdlines, for mapping of the pids to the task name.
Code has been added that only records the comm if a trace event occurred, and there's no reason to not trace it if the trace file is opened.
Cc: stable@vger.kernel.org Fixes: 7ffbd48d5cab2 ("tracing: Cache comms only after an event occurred") Signed-off-by: Steven Rostedt (VMware) rostedt@goodmis.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Yang Yingliang yangyingliang@huawei.com --- kernel/trace/trace.c | 9 --------- 1 file changed, 9 deletions(-)
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 9b03b8cff9285..475577163c0e9 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -1741,9 +1741,6 @@ struct saved_cmdlines_buffer { }; static struct saved_cmdlines_buffer *savedcmd;
-/* temporary disable recording */ -static atomic_t trace_record_taskinfo_disabled __read_mostly; - static inline char *get_saved_cmdlines(int idx) { return &savedcmd->saved_cmdlines[idx * TASK_COMM_LEN]; @@ -3254,9 +3251,6 @@ static void *s_start(struct seq_file *m, loff_t *pos) return ERR_PTR(-EBUSY); #endif
- if (!iter->snapshot) - atomic_inc(&trace_record_taskinfo_disabled); - if (*pos != iter->pos) { iter->ent = NULL; iter->cpu = 0; @@ -3299,9 +3293,6 @@ static void s_stop(struct seq_file *m, void *p) return; #endif
- if (!iter->snapshot) - atomic_dec(&trace_record_taskinfo_disabled); - trace_access_unlock(iter->cpu_file); trace_event_read_unlock(); }