From: Sebastien Buisson Date: Thu, 6 Jun 2013 12:39:13 +0000 (+0200) Subject: LU-2744 build: fix race issues thanks to oap_lock X-Git-Tag: 2.4.93~68 X-Git-Url: https://git.whamcloud.com/?p=fs%2Flustre-release.git;a=commitdiff_plain;h=0b2f943a317083a117d6f5f4a22e1d8233a7da77;hp=49d895fca7758498366328f2f6428b0edca75f77 LU-2744 build: fix race issues thanks to oap_lock Fix 'data race condition' defects found by Coverity version 6.5.0: Data race condition (MISSING_LOCK) Accessing variable without holding lock. Elsewhere, this variable is accessed with lock held. This patch is dedicated to code fragments involving oap_lock. Signed-off-by: Sebastien Buisson Change-Id: Ibfd5fe6338c624a1ab98b83ec621bcd88d736491 Reviewed-on: http://review.whamcloud.com/6572 Tested-by: Hudson Reviewed-by: Oleg Drokin Tested-by: Maloo Reviewed-by: Andreas Dilger --- diff --git a/lustre/osc/osc_cache.c b/lustre/osc/osc_cache.c index 8d9888f..11a5e0e 100644 --- a/lustre/osc/osc_cache.c +++ b/lustre/osc/osc_cache.c @@ -1079,7 +1079,9 @@ static int osc_extent_make_ready(const struct lu_env *env, last->oap_count = osc_refresh_count(env, last, OBD_BRW_WRITE); LASSERT(last->oap_count > 0); LASSERT(last->oap_page_off + last->oap_count <= PAGE_CACHE_SIZE); + spin_lock(&last->oap_lock); last->oap_async_flags |= ASYNC_COUNT_STABLE; + spin_unlock(&last->oap_lock); } /* for the rest of pages, we don't need to call osf_refresh_count() @@ -1087,7 +1089,9 @@ static int osc_extent_make_ready(const struct lu_env *env, cfs_list_for_each_entry(oap, &ext->oe_pages, oap_pending_item) { if (!(oap->oap_async_flags & ASYNC_COUNT_STABLE)) { oap->oap_count = PAGE_CACHE_SIZE - oap->oap_page_off; + spin_lock(&oap->oap_lock); oap->oap_async_flags |= ASYNC_COUNT_STABLE; + spin_unlock(&oap->oap_lock); } } @@ -2273,6 +2277,8 @@ int osc_queue_async_io(const struct lu_env *env, struct cl_io *io, oap->oap_cmd = cmd; oap->oap_page_off = ops->ops_from; oap->oap_count = ops->ops_to - ops->ops_from; + /* No need to hold a lock here, + * since this page is not in any list yet. */ oap->oap_async_flags = 0; oap->oap_brw_flags = brw_flags; diff --git a/lustre/osc/osc_io.c b/lustre/osc/osc_io.c index 110704c..bf93df5 100644 --- a/lustre/osc/osc_io.c +++ b/lustre/osc/osc_io.c @@ -164,8 +164,10 @@ static int osc_io_submit(const struct lu_env *env, } cl_page_list_move(qout, qin, page); + spin_lock(&oap->oap_lock); oap->oap_async_flags = ASYNC_URGENT|ASYNC_READY; oap->oap_async_flags |= ASYNC_COUNT_STABLE; + spin_unlock(&oap->oap_lock); osc_page_submit(env, opg, crt, brw_flags); cfs_list_add_tail(&oap->oap_pending_item, &list);