On Wed, Nov 9, 2022 at 3:12 PM Xiubo Li <xiubli@xxxxxxxxxx> wrote: > > > On 09/11/2022 20:56, Ilya Dryomov wrote: > > On Tue, Nov 8, 2022 at 2:56 PM <xiubli@xxxxxxxxxx> wrote: > >> From: Xiubo Li <xiubli@xxxxxxxxxx> > >> > >> The request's r_session maybe changed when it was forwarded or > >> resent. > >> > >> Cc: stable@xxxxxxxxxxxxxxx > >> URL: https://bugzilla.redhat.com/show_bug.cgi?id=2137955 > >> Signed-off-by: Xiubo Li <xiubli@xxxxxxxxxx> > >> --- > >> fs/ceph/caps.c | 60 ++++++++++++++++---------------------------------- > >> 1 file changed, 19 insertions(+), 41 deletions(-) > >> > >> diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c > >> index 894adfb4a092..83f9e18e3169 100644 > >> --- a/fs/ceph/caps.c > >> +++ b/fs/ceph/caps.c > >> @@ -2297,8 +2297,10 @@ static int flush_mdlog_and_wait_inode_unsafe_requests(struct inode *inode) > >> struct ceph_mds_client *mdsc = ceph_sb_to_client(inode->i_sb)->mdsc; > >> struct ceph_inode_info *ci = ceph_inode(inode); > >> struct ceph_mds_request *req1 = NULL, *req2 = NULL; > >> + struct ceph_mds_session **sessions = NULL; > >> + struct ceph_mds_session *s; > >> unsigned int max_sessions; > >> - int ret, err = 0; > >> + int i, ret, err = 0; > >> > >> spin_lock(&ci->i_unsafe_lock); > >> if (S_ISDIR(inode->i_mode) && !list_empty(&ci->i_unsafe_dirops)) { > >> @@ -2315,28 +2317,19 @@ static int flush_mdlog_and_wait_inode_unsafe_requests(struct inode *inode) > >> } > >> spin_unlock(&ci->i_unsafe_lock); > >> > >> - /* > >> - * The mdsc->max_sessions is unlikely to be changed > >> - * mostly, here we will retry it by reallocating the > >> - * sessions array memory to get rid of the mdsc->mutex > >> - * lock. > >> - */ > >> -retry: > >> - max_sessions = mdsc->max_sessions; > >> - > >> /* > >> * Trigger to flush the journal logs in all the relevant MDSes > >> * manually, or in the worst case we must wait at most 5 seconds > >> * to wait the journal logs to be flushed by the MDSes periodically. > >> */ > >> - if ((req1 || req2) && likely(max_sessions)) { > >> - struct ceph_mds_session **sessions = NULL; > >> - struct ceph_mds_session *s; > >> + mutex_lock(&mdsc->mutex); > >> + max_sessions = mdsc->max_sessions; > >> + if (req1 || req2) { > >> struct ceph_mds_request *req; > >> - int i; > >> > >> sessions = kcalloc(max_sessions, sizeof(s), GFP_KERNEL); > >> if (!sessions) { > >> + mutex_unlock(&mdsc->mutex); > >> err = -ENOMEM; > >> goto out; > >> } > >> @@ -2346,18 +2339,8 @@ static int flush_mdlog_and_wait_inode_unsafe_requests(struct inode *inode) > >> list_for_each_entry(req, &ci->i_unsafe_dirops, > >> r_unsafe_dir_item) { > >> s = req->r_session; > >> - if (!s) > >> + if (!s || unlikely(s->s_mds >= max_sessions)) > >> continue; > >> - if (unlikely(s->s_mds >= max_sessions)) { > >> - spin_unlock(&ci->i_unsafe_lock); > >> - for (i = 0; i < max_sessions; i++) { > >> - s = sessions[i]; > >> - if (s) > >> - ceph_put_mds_session(s); > >> - } > >> - kfree(sessions); > >> - goto retry; > >> - } > >> if (!sessions[s->s_mds]) { > >> s = ceph_get_mds_session(s); > >> sessions[s->s_mds] = s; > >> @@ -2368,18 +2351,8 @@ static int flush_mdlog_and_wait_inode_unsafe_requests(struct inode *inode) > >> list_for_each_entry(req, &ci->i_unsafe_iops, > >> r_unsafe_target_item) { > >> s = req->r_session; > >> - if (!s) > >> + if (!s || unlikely(s->s_mds >= max_sessions)) > >> continue; > >> - if (unlikely(s->s_mds >= max_sessions)) { > >> - spin_unlock(&ci->i_unsafe_lock); > >> - for (i = 0; i < max_sessions; i++) { > >> - s = sessions[i]; > >> - if (s) > >> - ceph_put_mds_session(s); > >> - } > >> - kfree(sessions); > >> - goto retry; > >> - } > >> if (!sessions[s->s_mds]) { > >> s = ceph_get_mds_session(s); > >> sessions[s->s_mds] = s; > >> @@ -2391,13 +2364,18 @@ static int flush_mdlog_and_wait_inode_unsafe_requests(struct inode *inode) > >> /* the auth MDS */ > >> spin_lock(&ci->i_ceph_lock); > >> if (ci->i_auth_cap) { > >> - s = ci->i_auth_cap->session; > >> - if (!sessions[s->s_mds]) > >> - sessions[s->s_mds] = ceph_get_mds_session(s); > >> + s = ci->i_auth_cap->session; > >> + if (likely(s->s_mds < max_sessions) > >> + && !sessions[s->s_mds]) { > > Hi Xiubo, > > > > Nit: keep && on the previous line for style consistency. > > Sure. Will fix it. > > > > > >> + sessions[s->s_mds] = ceph_get_mds_session(s); > >> + } > >> } > >> spin_unlock(&ci->i_ceph_lock); > >> + } > >> + mutex_unlock(&mdsc->mutex); > >> > >> - /* send flush mdlog request to MDSes */ > >> + /* send flush mdlog request to MDSes */ > >> + if (sessions) { > > Since mdlog is flushed only in "if (req1 || req2)" case, why not keep > > max_sessions loop there and avoid sessions != NULL check? > > This is because I must drop the mdsc->mutex before calling > "send_flush_mdlog()" in the max_sessions loop. If you move mdsc->mutex acquisition and max_sessions assignment into "if (req1 || req2)" branch, it can be trivially dropped before the loop. Thanks, Ilya
