From: Kaitao Cheng Date: Tue, 31 Dec 2019 13:35:30 +0000 (-0800) Subject: kernel/trace: Fix do not unregister tracepoints when register sched_migrate_task... X-Git-Tag: v3.16.83~92 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=5d6c167fb5498bc3c32dfcb37f144ceb5c2d9138;p=thirdparty%2Fkernel%2Fstable.git kernel/trace: Fix do not unregister tracepoints when register sched_migrate_task fail commit 50f9ad607ea891a9308e67b81f774c71736d1098 upstream. In the function, if register_trace_sched_migrate_task() returns error, sched_switch/sched_wakeup_new/sched_wakeup won't unregister. That is why fail_deprobe_sched_switch was added. Link: http://lkml.kernel.org/r/20191231133530.2794-1-pilgrimtao@gmail.com Fixes: 478142c39c8c2 ("tracing: do not grab lock in wakeup latency function tracing") Signed-off-by: Kaitao Cheng Signed-off-by: Steven Rostedt (VMware) Signed-off-by: Ben Hutchings --- diff --git a/kernel/trace/trace_sched_wakeup.c b/kernel/trace/trace_sched_wakeup.c index 19bd8928ce944..0928ea8c55675 100644 --- a/kernel/trace/trace_sched_wakeup.c +++ b/kernel/trace/trace_sched_wakeup.c @@ -567,7 +567,7 @@ static void start_wakeup_tracer(struct trace_array *tr) if (ret) { pr_info("wakeup trace: Couldn't activate tracepoint" " probe to kernel_sched_migrate_task\n"); - return; + goto fail_deprobe_sched_switch; } wakeup_reset(tr); @@ -585,6 +585,8 @@ static void start_wakeup_tracer(struct trace_array *tr) printk(KERN_ERR "failed to start wakeup tracer\n"); return; +fail_deprobe_sched_switch: + unregister_trace_sched_switch(probe_wakeup_sched_switch, NULL); fail_deprobe_wake_new: unregister_trace_sched_wakeup_new(probe_wakeup, NULL); fail_deprobe: