Messages in this thread Patches in this message |  | | | From | NeilBrown <> | | Date | Fri, 1 Sep 2006 14:39:27 +1000 | | Subject | [PATCH 015 of 19] knfsd: make nlmclnt_next_cookie SMP safe |
From: Olaf Kirch <okir@suse.de>
The way we incremented the NLM cookie in nlmclnt_next_cookie was not thread safe. This patch changes the counter to an atomic_t
Signed-off-by: Olaf Kirch <okir@suse.de> Signed-off-by: Neil Brown <neilb@suse.de>
### Diffstat output ./fs/lockd/clntproc.c | 10 +++++----- ./include/linux/lockd/lockd.h | 1 + 2 files changed, 6 insertions(+), 5 deletions(-) diff .prev/fs/lockd/clntproc.c ./fs/lockd/clntproc.c --- .prev/fs/lockd/clntproc.c 2006-09-01 12:11:03.000000000 +1000 +++ ./fs/lockd/clntproc.c 2006-09-01 12:17:03.000000000 +1000 @@ -36,14 +36,14 @@ static const struct rpc_call_ops nlmclnt /* * Cookie counter for NLM requests */ -static u32 nlm_cookie = 0x1234; +static atomic_t nlm_cookie = ATOMIC_INIT(0x1234); -static inline void nlmclnt_next_cookie(struct nlm_cookie *c) +void nlmclnt_next_cookie(struct nlm_cookie *c) { - memcpy(c->data, &nlm_cookie, 4); - memset(c->data+4, 0, 4); + u32 cookie = atomic_inc_return(&nlm_cookie); + + memcpy(c->data, &cookie, 4); c->len=4; - nlm_cookie++; } static struct nlm_lockowner *nlm_get_lockowner(struct nlm_lockowner *lockowner) diff .prev/include/linux/lockd/lockd.h ./include/linux/lockd/lockd.h --- .prev/include/linux/lockd/lockd.h 2006-09-01 12:16:06.000000000 +1000 +++ ./include/linux/lockd/lockd.h 2006-09-01 12:17:03.000000000 +1000 @@ -157,6 +157,7 @@ int nlmclnt_block(struct nlm_wait *bl u32 nlmclnt_grant(const struct sockaddr_in *addr, const struct nlm_lock *); void nlmclnt_recovery(struct nlm_host *); int nlmclnt_reclaim(struct nlm_host *, struct file_lock *); +void nlmclnt_next_cookie(struct nlm_cookie *); /* * Host cache - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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