locking, latencytop: Annotate latency_lock as raw
The latency_lock is lock can be taken in the guts of the
scheduler code and therefore cannot be preempted on -rt -
annotate it.
In mainline this change documents the low level nature of
the lock - otherwise there's no functional difference. Lockdep
and Sparse checking will work as usual.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/kernel/latencytop.c b/kernel/latencytop.c
index 376066e..4ac8ebf 100644
--- a/kernel/latencytop.c
+++ b/kernel/latencytop.c
@@ -58,7 +58,7 @@
#include <linux/list.h>
#include <linux/stacktrace.h>
-static DEFINE_SPINLOCK(latency_lock);
+static DEFINE_RAW_SPINLOCK(latency_lock);
#define MAXLR 128
static struct latency_record latency_record[MAXLR];
@@ -72,19 +72,19 @@
if (!latencytop_enabled)
return;
- spin_lock_irqsave(&latency_lock, flags);
+ raw_spin_lock_irqsave(&latency_lock, flags);
memset(&p->latency_record, 0, sizeof(p->latency_record));
p->latency_record_count = 0;
- spin_unlock_irqrestore(&latency_lock, flags);
+ raw_spin_unlock_irqrestore(&latency_lock, flags);
}
static void clear_global_latency_tracing(void)
{
unsigned long flags;
- spin_lock_irqsave(&latency_lock, flags);
+ raw_spin_lock_irqsave(&latency_lock, flags);
memset(&latency_record, 0, sizeof(latency_record));
- spin_unlock_irqrestore(&latency_lock, flags);
+ raw_spin_unlock_irqrestore(&latency_lock, flags);
}
static void __sched
@@ -190,7 +190,7 @@
lat.max = usecs;
store_stacktrace(tsk, &lat);
- spin_lock_irqsave(&latency_lock, flags);
+ raw_spin_lock_irqsave(&latency_lock, flags);
account_global_scheduler_latency(tsk, &lat);
@@ -231,7 +231,7 @@
memcpy(&tsk->latency_record[i], &lat, sizeof(struct latency_record));
out_unlock:
- spin_unlock_irqrestore(&latency_lock, flags);
+ raw_spin_unlock_irqrestore(&latency_lock, flags);
}
static int lstats_show(struct seq_file *m, void *v)
