From 47474d0b011bb385719e91a60bb9ff7649d66526 Mon Sep 17 00:00:00 2001 From: Chengguang Xu Date: Tue, 13 Mar 2018 23:01:07 +0800 Subject: [PATCH] ceph: optimize mds session register Do memory allocation first, so that avoid unnecessary initialization of newly allocated session in error case. Signed-off-by: Chengguang Xu Reviewed-by: "Yan, Zheng" Signed-off-by: Ilya Dryomov --- fs/ceph/mds_client.c | 36 +++++++++++++++++++----------------- 1 file changed, 19 insertions(+), 17 deletions(-) diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c index b9cbeeb32ab3..a511a777ffb9 100644 --- a/fs/ceph/mds_client.c +++ b/fs/ceph/mds_client.c @@ -448,6 +448,25 @@ static struct ceph_mds_session *register_session(struct ceph_mds_client *mdsc, s = kzalloc(sizeof(*s), GFP_NOFS); if (!s) return ERR_PTR(-ENOMEM); + + if (mds >= mdsc->max_sessions) { + int newmax = 1 << get_count_order(mds + 1); + struct ceph_mds_session **sa; + + dout("%s: realloc to %d\n", __func__, newmax); + sa = kcalloc(newmax, sizeof(void *), GFP_NOFS); + if (!sa) + goto fail_realloc; + if (mdsc->sessions) { + memcpy(sa, mdsc->sessions, + mdsc->max_sessions * sizeof(void *)); + kfree(mdsc->sessions); + } + mdsc->sessions = sa; + mdsc->max_sessions = newmax; + } + + dout("%s: mds%d\n", __func__, mds); s->s_mdsc = mdsc; s->s_mds = mds; s->s_state = CEPH_MDS_SESSION_NEW; @@ -476,23 +495,6 @@ static struct ceph_mds_session *register_session(struct ceph_mds_client *mdsc, INIT_LIST_HEAD(&s->s_cap_releases); INIT_LIST_HEAD(&s->s_cap_flushing); - dout("register_session mds%d\n", mds); - if (mds >= mdsc->max_sessions) { - int newmax = 1 << get_count_order(mds+1); - struct ceph_mds_session **sa; - - dout("register_session realloc to %d\n", newmax); - sa = kcalloc(newmax, sizeof(void *), GFP_NOFS); - if (!sa) - goto fail_realloc; - if (mdsc->sessions) { - memcpy(sa, mdsc->sessions, - mdsc->max_sessions * sizeof(void *)); - kfree(mdsc->sessions); - } - mdsc->sessions = sa; - mdsc->max_sessions = newmax; - } mdsc->sessions[mds] = s; atomic_inc(&mdsc->num_sessions); refcount_inc(&s->s_ref); /* one ref to sessions[], one to caller */ -- 2.30.2