From 7e255d346c12888f7cce4b89a03a5fe5e9196ab1 Mon Sep 17 00:00:00 2001 From: Jerry Snitselaar Date: Thu, 30 Apr 2015 08:10:24 -0700 Subject: [PATCH] tracing: Export tracing clock functions Critical tracepoint hooks should never call anything that takes a lock, so they are unable to call getrawmonotonic() or ktime_get(). Export the rest of the tracing clock functions so can be used in tracepoint hooks. Background: We have a customer that adds their own module and registers a tracepoint hook to sched_wakeup. They were using ktime_get() for a time source, but it grabs a seq lock and caused a deadlock to occur. Link: http://lkml.kernel.org/r/1430406624-22609-1-git-send-email-jsnitsel@redhat.com Signed-off-by: Jerry Snitselaar Signed-off-by: Steven Rostedt --- kernel/trace/trace_clock.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/kernel/trace/trace_clock.c b/kernel/trace/trace_clock.c index 57b67b1f24d1..0f06532a755b 100644 --- a/kernel/trace/trace_clock.c +++ b/kernel/trace/trace_clock.c @@ -56,6 +56,7 @@ u64 notrace trace_clock(void) { return local_clock(); } +EXPORT_SYMBOL_GPL(trace_clock); /* * trace_jiffy_clock(): Simply use jiffies as a clock counter. @@ -68,6 +69,7 @@ u64 notrace trace_clock_jiffies(void) { return jiffies_64_to_clock_t(jiffies_64 - INITIAL_JIFFIES); } +EXPORT_SYMBOL_GPL(trace_clock_jiffies); /* * trace_clock_global(): special globally coherent trace clock @@ -123,6 +125,7 @@ u64 notrace trace_clock_global(void) return now; } +EXPORT_SYMBOL_GPL(trace_clock_global); static atomic64_t trace_counter; -- GitLab