From 5d47648fe95412beffe2089d6d6484adb5ea0f96 Mon Sep 17 00:00:00 2001 From: Xiubo Li Date: Tue, 26 Nov 2019 07:24:22 -0500 Subject: [PATCH] ceph: only choose one MDS who is in up:active state without laggy Even the MDS is in up:active state, but it also maybe laggy. Here will skip the laggy MDSs. Signed-off-by: Xiubo Li Reviewed-by: Jeff Layton Signed-off-by: Ilya Dryomov --- fs/ceph/mds_client.c | 13 +++++++++---- fs/ceph/mdsmap.c | 30 +++++++++++++++++++++++------- 2 files changed, 32 insertions(+), 11 deletions(-) diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c index 69631d1..1b53ace 100644 --- a/fs/ceph/mds_client.c +++ b/fs/ceph/mds_client.c @@ -974,14 +974,14 @@ static int __choose_mds(struct ceph_mds_client *mdsc, frag.frag, mds, (int)r, frag.ndist); if (ceph_mdsmap_get_state(mdsc->mdsmap, mds) >= - CEPH_MDS_STATE_ACTIVE) + CEPH_MDS_STATE_ACTIVE && + !ceph_mdsmap_is_laggy(mdsc->mdsmap, mds)) goto out; } /* since this file/dir wasn't known to be * replicated, then we want to look for the * authoritative mds. */ - mode = USE_AUTH_MDS; if (frag.mds >= 0) { /* choose auth mds */ mds = frag.mds; @@ -989,9 +989,14 @@ static int __choose_mds(struct ceph_mds_client *mdsc, "frag %u mds%d (auth)\n", inode, ceph_vinop(inode), frag.frag, mds); if (ceph_mdsmap_get_state(mdsc->mdsmap, mds) >= - CEPH_MDS_STATE_ACTIVE) - goto out; + CEPH_MDS_STATE_ACTIVE) { + if (mode == USE_ANY_MDS && + !ceph_mdsmap_is_laggy(mdsc->mdsmap, + mds)) + goto out; + } } + mode = USE_AUTH_MDS; } } diff --git a/fs/ceph/mdsmap.c b/fs/ceph/mdsmap.c index 7a925e0..a77e0ec 100644 --- a/fs/ceph/mdsmap.c +++ b/fs/ceph/mdsmap.c @@ -13,22 +13,24 @@ #include "super.h" +#define CEPH_MDS_IS_READY(i, ignore_laggy) \ + (m->m_info[i].state > 0 && (ignore_laggy ? true : !m->m_info[i].laggy)) -/* - * choose a random mds that is "up" (i.e. has a state > 0), or -1. - */ -int ceph_mdsmap_get_random_mds(struct ceph_mdsmap *m) +static int __mdsmap_get_random_mds(struct ceph_mdsmap *m, bool ignore_laggy) { int n = 0; int i, j; - /* special case for one mds */ + /* + * special case for one mds, no matter it is laggy or + * not we have no choice + */ if (1 == m->m_num_mds && m->m_info[0].state > 0) return 0; /* count */ for (i = 0; i < m->m_num_mds; i++) - if (m->m_info[i].state > 0) + if (CEPH_MDS_IS_READY(i, ignore_laggy)) n++; if (n == 0) return -1; @@ -36,7 +38,7 @@ int ceph_mdsmap_get_random_mds(struct ceph_mdsmap *m) /* pick */ n = prandom_u32() % n; for (j = 0, i = 0; i < m->m_num_mds; i++) { - if (m->m_info[i].state > 0) + if (CEPH_MDS_IS_READY(i, ignore_laggy)) j++; if (j > n) break; @@ -45,6 +47,20 @@ int ceph_mdsmap_get_random_mds(struct ceph_mdsmap *m) return i; } +/* + * choose a random mds that is "up" (i.e. has a state > 0), or -1. + */ +int ceph_mdsmap_get_random_mds(struct ceph_mdsmap *m) +{ + int mds; + + mds = __mdsmap_get_random_mds(m, false); + if (mds == m->m_num_mds || mds == -1) + mds = __mdsmap_get_random_mds(m, true); + + return mds == m->m_num_mds ? -1 : mds; +} + #define __decode_and_drop_type(p, end, type, bad) \ do { \ if (*p + sizeof(type) > end) \ -- 2.7.4