ceph: only choose one MDS who is in up:active state without laggy (5d47648f) · Commits · 戴 / test

fs/ceph/mds_client.c

+9 −4

Original line number	Diff line number	Diff line
		@@ -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;
		@@ -989,10 +989,15 @@ 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)
		CEPH_MDS_STATE_ACTIVE) {
		if (mode == USE_ANY_MDS &&
		!ceph_mdsmap_is_laggy(mdsc->mdsmap,
		mds))
		goto out;
		}
		}
		mode = USE_AUTH_MDS;
		}
		}

		spin_lock(&ci->i_ceph_lock);

+23 −7

Original line number	Diff line number	Diff line
		@@ -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) \