[dpdk-dev] eal: protect malloc stats with lock

Message ID 39635342ba1c29bc96bee904e6b888b058f0a5ca.1513865781.git.anatoly.burakov@intel.com (mailing list archive)
State Accepted, archived
Delegated to: Thomas Monjalon
Headers

Checks

Context Check Description
ci/checkpatch success coding style OK
ci/Intel-compilation success Compilation OK

Commit Message

Anatoly Burakov Dec. 21, 2017, 5:32 p.m. UTC
  When we're gathering statistics, we are traversing the freelist,
which may change under our feet in multithreaded scenario. This
is verified by occasional segfaults when running malloc autotest
on a machine with big amount of cores.

This patch protects malloc heap stats call with a lock. It changes
its definition in the process due to locking invalidating the
const-ness, but this isn't a public API, so that's OK.

Cc: stable@dpdk.org
Signed-off-by: Anatoly Burakov <anatoly.burakov@intel.com>
---
 lib/librte_eal/common/malloc_heap.c | 6 +++++-
 lib/librte_eal/common/malloc_heap.h | 2 +-
 2 files changed, 6 insertions(+), 2 deletions(-)
  

Comments

Thomas Monjalon Jan. 12, 2018, 2:42 p.m. UTC | #1
21/12/2017 18:32, Anatoly Burakov:
> When we're gathering statistics, we are traversing the freelist,
> which may change under our feet in multithreaded scenario. This
> is verified by occasional segfaults when running malloc autotest
> on a machine with big amount of cores.
> 
> This patch protects malloc heap stats call with a lock. It changes
> its definition in the process due to locking invalidating the
> const-ness, but this isn't a public API, so that's OK.
> 
> Cc: stable@dpdk.org
> Signed-off-by: Anatoly Burakov <anatoly.burakov@intel.com>

Applied, thanks
  

Patch

diff --git a/lib/librte_eal/common/malloc_heap.c b/lib/librte_eal/common/malloc_heap.c
index 267a4c6..c731f1c 100644
--- a/lib/librte_eal/common/malloc_heap.c
+++ b/lib/librte_eal/common/malloc_heap.c
@@ -178,12 +178,14 @@  malloc_heap_alloc(struct malloc_heap *heap,
  * Function to retrieve data for heap on given socket
  */
 int
-malloc_heap_get_stats(const struct malloc_heap *heap,
+malloc_heap_get_stats(struct malloc_heap *heap,
 		struct rte_malloc_socket_stats *socket_stats)
 {
 	size_t idx;
 	struct malloc_elem *elem;
 
+	rte_spinlock_lock(&heap->lock);
+
 	/* Initialise variables for heap */
 	socket_stats->free_count = 0;
 	socket_stats->heap_freesz_bytes = 0;
@@ -205,6 +207,8 @@  malloc_heap_get_stats(const struct malloc_heap *heap,
 	socket_stats->heap_allocsz_bytes = (socket_stats->heap_totalsz_bytes -
 			socket_stats->heap_freesz_bytes);
 	socket_stats->alloc_count = heap->alloc_count;
+
+	rte_spinlock_unlock(&heap->lock);
 	return 0;
 }
 
diff --git a/lib/librte_eal/common/malloc_heap.h b/lib/librte_eal/common/malloc_heap.h
index 3ccbef0..3b1166f 100644
--- a/lib/librte_eal/common/malloc_heap.h
+++ b/lib/librte_eal/common/malloc_heap.h
@@ -57,7 +57,7 @@  malloc_heap_alloc(struct malloc_heap *heap,	const char *type, size_t size,
 		unsigned flags, size_t align, size_t bound);
 
 int
-malloc_heap_get_stats(const struct malloc_heap *heap,
+malloc_heap_get_stats(struct malloc_heap *heap,
 		struct rte_malloc_socket_stats *socket_stats);
 
 int