Commit 3b09b2bd authored by Eric Dumazet's avatar Eric Dumazet Committed by Jakub Kicinski
Browse files

net: dst_cache: annotate data-races around dst_cache->reset_ts 



dst_cache->reset_ts is read or written locklessly,
add READ_ONCE() and WRITE_ONCE() annotations.

Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
Acked-by: default avatarPaolo Abeni <pabeni@redhat.com>
Link: https://lore.kernel.org/r/20240507132000.614591-1-edumazet@google.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent e497c322

include/net/dst_cache.h

+1 −1
Original line number Diff line number Diff line
@@ -76,7 +76,7 @@ struct dst_entry *dst_cache_get_ip6(struct dst_cache *dst_cache, 
 */

static inline void dst_cache_reset(struct dst_cache *dst_cache)

{

	dst_cache->reset_ts = jiffies;

	WRITE_ONCE(dst_cache->reset_ts, jiffies);

}



/**

net/core/dst_cache.c

+3 −2
Original line number Diff line number Diff line
@@ -47,7 +47,8 @@ static struct dst_entry *dst_cache_per_cpu_get(struct dst_cache *dst_cache, 
	/* the cache already hold a dst reference; it can't go away */

	dst_hold(dst);



	if (unlikely(!time_after(idst->refresh_ts, dst_cache->reset_ts) ||

	if (unlikely(!time_after(idst->refresh_ts,

				 READ_ONCE(dst_cache->reset_ts)) ||

		     (dst->obsolete && !dst->ops->check(dst, idst->cookie)))) {

		dst_cache_per_cpu_dst_set(idst, NULL, 0);

		dst_release(dst);
@@ -170,7 +171,7 @@ void dst_cache_reset_now(struct dst_cache *dst_cache) 
	if (!dst_cache->cache)

		return;



	dst_cache->reset_ts = jiffies;

	dst_cache_reset(dst_cache);

	for_each_possible_cpu(i) {

		struct dst_cache_pcpu *idst = per_cpu_ptr(dst_cache->cache, i);

		struct dst_entry *dst = idst->dst;