From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sunil Mushran Date: Wed, 24 Mar 2010 14:41:51 -0700 Subject: [Ocfs2-devel] [PATCH] ocfs2: be within spinlock when checking the owner of a lockres In-Reply-To: <201003241442.o2NAdfs4028087@acsinet15.oracle.com> References: <201003241442.o2NAdfs4028087@acsinet15.oracle.com> Message-ID: <4BAA871F.7030200@oracle.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: ocfs2-devel@oss.oracle.com Signed-off-by: Sunil Mushran Wengang Wang wrote: > The checking of lockres owner in dlm_update_lvb() is not with spinlock > protection. I don't see problem in current call path of dlm_update_lvb(). > But just for code robustness. > > Signed-off-by: Wengang Wang > --- > fs/ocfs2/dlm/dlmast.c | 5 ++--- > 1 files changed, 2 insertions(+), 3 deletions(-) > > diff --git a/fs/ocfs2/dlm/dlmast.c b/fs/ocfs2/dlm/dlmast.c > index dccc439..b7a25ef 100644 > --- a/fs/ocfs2/dlm/dlmast.c > +++ b/fs/ocfs2/dlm/dlmast.c > @@ -185,9 +185,8 @@ static void dlm_update_lvb(struct dlm_ctxt *dlm, struct dlm_lock_resource *res, > BUG_ON(!lksb); > > /* only updates if this node masters the lockres */ > + spin_lock(&res->spinlock); > if (res->owner == dlm->node_num) { > - > - spin_lock(&res->spinlock); > /* check the lksb flags for the direction */ > if (lksb->flags & DLM_LKSB_GET_LVB) { > mlog(0, "getting lvb from lockres for %s node\n", > @@ -202,8 +201,8 @@ static void dlm_update_lvb(struct dlm_ctxt *dlm, struct dlm_lock_resource *res, > * here. In the future we might want to clear it at the time > * the put is actually done. > */ > - spin_unlock(&res->spinlock); > } > + spin_unlock(&res->spinlock); > > /* reset any lvb flags on the lksb */ > lksb->flags &= ~(DLM_LKSB_PUT_LVB|DLM_LKSB_GET_LVB); >