prempt_disable/enable tracepoints occurs only in the preemption
enabled <-> disable transition. As preempt_latency_stop() and
preempt_latency_start() already do this control, avoid code
duplication by using these functions in the softirq code as well.
RFC: Should we move preempt_latency_start/preempt_latency_stop
to a trace source file... or even a header?
Signed-off-by: Daniel Bristot de Oliveira <bris...@redhat.com>
Cc: "Steven Rostedt (VMware)" <rost...@goodmis.org>
Cc: Ingo Molnar <mi...@redhat.com>
Cc: Peter Zijlstra <pet...@infradead.org>
Cc: Thomas Gleixner <t...@linutronix.de>
Cc: "Paul E. McKenney" <paul...@linux.vnet.ibm.com>
Cc: Matthias Kaehlcke <m...@chromium.org>
Cc: "Joel Fernandes (Google)" <j...@joelfernandes.org>
Cc: Frederic Weisbecker <frede...@kernel.org>
Cc: Yangtao Li <tiny.win...@gmail.com>
Cc: Tommaso Cucinotta <tommaso.cucino...@santannapisa.it>
Cc: linux-kernel@vger.kernel.org
---
kernel/sched/core.c | 4 ++--
kernel/softirq.c | 13 +++++--------
2 files changed, 7 insertions(+), 10 deletions(-)
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 874c427742a9..8c0b414e45dc 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -3152,7 +3152,7 @@ static inline void sched_tick_stop(int cpu) { }
* If the value passed in is equal to the current preempt count
* then we just disabled preemption. Start timing the latency.
*/
-static inline void preempt_latency_start(int val)
+void preempt_latency_start(int val)
{
if (preempt_count() == val) {
unsigned long ip = get_lock_parent_ip();
@@ -3189,7 +3189,7 @@ NOKPROBE_SYMBOL(preempt_count_add);
* If the value passed in equals to the current preempt count
* then we just enabled preemption. Stop timing the latency.
*/
-static inline void preempt_latency_stop(int val)
+void preempt_latency_stop(int val)
{
if (preempt_count() == val)
trace_preempt_on(CALLER_ADDR0, get_lock_parent_ip());
diff --git a/kernel/softirq.c b/kernel/softirq.c
index 2c3382378d94..c9ad89c3dfed 100644
--- a/kernel/softirq.c
+++ b/kernel/softirq.c
@@ -108,6 +108,8 @@ static bool ksoftirqd_running(unsigned long pending)
* where hardirqs are disabled legitimately:
*/
#ifdef CONFIG_TRACE_IRQFLAGS
+extern void preempt_latency_start(int val);
+extern void preempt_latency_stop(int val);
void __local_bh_disable_ip(unsigned long ip, unsigned int cnt)
{
unsigned long flags;
@@ -130,12 +132,8 @@ void __local_bh_disable_ip(unsigned long ip, unsigned int
cnt)
trace_softirqs_off(ip);
raw_local_irq_restore(flags);
- if (preempt_count() == cnt) {
-#ifdef CONFIG_DEBUG_PREEMPT
- current->preempt_disable_ip = get_lock_parent_ip();
-#endif
- trace_preempt_off(CALLER_ADDR0, get_lock_parent_ip());
- }
+ preempt_latency_start(cnt);
+
}
EXPORT_SYMBOL(__local_bh_disable_ip);
#endif /* CONFIG_TRACE_IRQFLAGS */
@@ -144,8 +142,7 @@ static void __local_bh_enable(unsigned int cnt)
{
lockdep_assert_irqs_disabled();
- if (preempt_count() == cnt)
- trace_preempt_on(CALLER_ADDR0, get_lock_parent_ip());
+ preempt_latency_stop(cnt);
if (softirq_count() == (cnt & SOFTIRQ_MASK))
trace_softirqs_on(_RET_IP_);
--
2.20.1
