[PATCH] percpu: improve percpu_alloc_percpu_fail event trace

[George Guo]

From: George Guo <guodongtai@xxxxxxxxxx>

Add do_warn, warn_limit fields to the output of the
percpu_alloc_percpu_fail ftrace event.

This is required to percpu_alloc failed with no warning showing.

Signed-off-by: George Guo <guodongtai@xxxxxxxxxx>
---
 include/trace/events/percpu.h | 22 ++++++++++++++--------
 mm/percpu.c                   |  2 +-
 2 files changed, 15 insertions(+), 9 deletions(-)

diff --git a/include/trace/events/percpu.h b/include/trace/events/percpu.h
index 5b8211ca8950..c5f412e84bb8 100644
--- a/include/trace/events/percpu.h
+++ b/include/trace/events/percpu.h
@@ -75,15 +75,18 @@ TRACE_EVENT(percpu_free_percpu,
 
 TRACE_EVENT(percpu_alloc_percpu_fail,
 
-	TP_PROTO(bool reserved, bool is_atomic, size_t size, size_t align),
+	TP_PROTO(bool reserved, bool is_atomic, size_t size, size_t align,
+		 bool do_warn, int warn_limit),
 
-	TP_ARGS(reserved, is_atomic, size, align),
+	TP_ARGS(reserved, is_atomic, size, align, do_warn, warn_limit),
 
 	TP_STRUCT__entry(
-		__field(	bool,	reserved	)
-		__field(	bool,	is_atomic	)
-		__field(	size_t,	size		)
-		__field(	size_t, align		)
+		__field(bool,	reserved)
+		__field(bool,	is_atomic)
+		__field(size_t,	size)
+		__field(size_t, align)
+		__field(bool,	do_warn)
+		__field(int,	warn_limit)
 	),
 
 	TP_fast_assign(
@@ -91,11 +94,14 @@ TRACE_EVENT(percpu_alloc_percpu_fail,
 		__entry->is_atomic	= is_atomic;
 		__entry->size		= size;
 		__entry->align		= align;
+		__entry->do_warn	= do_warn;
+		__entry->warn_limit	= warn_limit;
 	),
 
-	TP_printk("reserved=%d is_atomic=%d size=%zu align=%zu",
+	TP_printk("reserved=%d is_atomic=%d size=%zu align=%zu do_warn=%d, warn_limit=%d",
 		  __entry->reserved, __entry->is_atomic,
-		  __entry->size, __entry->align)
+		  __entry->size, __entry->align,
+		  __entry->do_warn, __entry->warn_limit)
 );
 
 TRACE_EVENT(percpu_create_chunk,
diff --git a/mm/percpu.c b/mm/percpu.c
index 4e11fc1e6def..ac5b48268c99 100644
--- a/mm/percpu.c
+++ b/mm/percpu.c
@@ -1886,7 +1886,7 @@ static void __percpu *pcpu_alloc(size_t size, size_t align, bool reserved,
 fail_unlock:
 	spin_unlock_irqrestore(&pcpu_lock, flags);
 fail:
-	trace_percpu_alloc_percpu_fail(reserved, is_atomic, size, align);
+	trace_percpu_alloc_percpu_fail(reserved, is_atomic, size, align, do_warn, warn_limit);
 
 	if (do_warn && warn_limit) {
 		pr_warn("allocation failed, size=%zu align=%zu atomic=%d, %s\n",
-- 
2.34.1