From 6802e3400ff4549525930ee744030c36fce9cc73 Mon Sep 17 00:00:00 2001 From: Steven Whitehouse Date: Wed, 21 May 2008 17:03:22 +0100 Subject: [GFS2] Clean up the glock core This patch implements a number of cleanups to the core of the GFS2 glock code. As a result a lot of code is removed. It looks like a really big change, but actually a large part of this patch is either removing or moving existing code. There are some new bits too though, such as the new run_queue() function which is considerably streamlined. Highlights of this patch include: o Fixes a cluster coherency bug during SH -> EX lock conversions o Removes the "glmutex" code in favour of a single bit lock o Removes the ->go_xmote_bh() for inodes since it was duplicating ->go_lock() o We now only use the ->lm_lock() function for both locks and unlocks (i.e. unlock is a lock with target mode LM_ST_UNLOCKED) o The fast path is considerably shortly, giving performance gains especially with lock_nolock o The glock_workqueue is now used for all the callbacks from the DLM which allows us to simplify the lock_dlm module (see following patch) o The way is now open to make further changes such as eliminating the two threads (gfs2_glockd and gfs2_scand) in favour of a more efficient scheme. This patch has undergone extensive testing with various test suites so it should be pretty stable by now. Signed-off-by: Steven Whitehouse Cc: Bob Peterson --- fs/gfs2/glock.h | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) (limited to 'fs/gfs2/glock.h') diff --git a/fs/gfs2/glock.h b/fs/gfs2/glock.h index cdad3e6f8150..7389f8ef0a31 100644 --- a/fs/gfs2/glock.h +++ b/fs/gfs2/glock.h @@ -26,11 +26,8 @@ #define GL_SKIP 0x00000100 #define GL_ATIME 0x00000200 #define GL_NOCACHE 0x00000400 -#define GL_FLOCK 0x00000800 -#define GL_NOCANCEL 0x00001000 #define GLR_TRYFAILED 13 -#define GLR_CANCELED 14 static inline struct gfs2_holder *gfs2_glock_is_locked_by_me(struct gfs2_glock *gl) { @@ -41,6 +38,8 @@ static inline struct gfs2_holder *gfs2_glock_is_locked_by_me(struct gfs2_glock * spin_lock(&gl->gl_spin); pid = task_pid(current); list_for_each_entry(gh, &gl->gl_holders, gh_list) { + if (!test_bit(HIF_HOLDER, &gh->gh_iflags)) + break; if (gh->gh_owner_pid == pid) goto out; } @@ -70,7 +69,7 @@ static inline int gfs2_glock_is_blocking(struct gfs2_glock *gl) { int ret; spin_lock(&gl->gl_spin); - ret = test_bit(GLF_DEMOTE, &gl->gl_flags) || !list_empty(&gl->gl_waiters3); + ret = test_bit(GLF_DEMOTE, &gl->gl_flags); spin_unlock(&gl->gl_spin); return ret; } @@ -98,6 +97,7 @@ int gfs2_glock_nq_num(struct gfs2_sbd *sdp, int gfs2_glock_nq_m(unsigned int num_gh, struct gfs2_holder *ghs); void gfs2_glock_dq_m(unsigned int num_gh, struct gfs2_holder *ghs); void gfs2_glock_dq_uninit_m(unsigned int num_gh, struct gfs2_holder *ghs); +void gfs2_print_dbg(struct seq_file *seq, const char *fmt, ...); /** * gfs2_glock_nq_init - intialize a holder and enqueue it on a glock @@ -130,7 +130,6 @@ int gfs2_lvb_hold(struct gfs2_glock *gl); void gfs2_lvb_unhold(struct gfs2_glock *gl); void gfs2_glock_cb(void *cb_data, unsigned int type, void *data); - void gfs2_glock_schedule_for_reclaim(struct gfs2_glock *gl); void gfs2_reclaim_glock(struct gfs2_sbd *sdp); void gfs2_gl_hash_clear(struct gfs2_sbd *sdp, int wait); -- cgit v1.2.3 From 1bdad606338debc6384b2844f1b53cc436b3ac90 Mon Sep 17 00:00:00 2001 From: Steven Whitehouse Date: Tue, 3 Jun 2008 14:09:53 +0100 Subject: [GFS2] Remove remote lock dropping code There are several reasons why this is undesirable: 1. It never happens during normal operation anyway 2. If it does happen it causes performance to be very, very poor 3. It isn't likely to solve the original problem (memory shortage on remote DLM node) it was supposed to solve 4. It uses a bunch of arbitrary constants which are unlikely to be correct for any particular situation and for which the tuning seems to be a black art. 5. In an N node cluster, only 1/N of the dropped locked will actually contribute to solving the problem on average. So all in all we are better off without it. This also makes merging the lock_dlm module into GFS2 a bit easier. Signed-off-by: Steven Whitehouse --- fs/gfs2/glock.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'fs/gfs2/glock.h') diff --git a/fs/gfs2/glock.h b/fs/gfs2/glock.h index 7389f8ef0a31..971d92af70fc 100644 --- a/fs/gfs2/glock.h +++ b/fs/gfs2/glock.h @@ -132,7 +132,7 @@ void gfs2_lvb_unhold(struct gfs2_glock *gl); void gfs2_glock_cb(void *cb_data, unsigned int type, void *data); void gfs2_glock_schedule_for_reclaim(struct gfs2_glock *gl); void gfs2_reclaim_glock(struct gfs2_sbd *sdp); -void gfs2_gl_hash_clear(struct gfs2_sbd *sdp, int wait); +void gfs2_gl_hash_clear(struct gfs2_sbd *sdp); int __init gfs2_glock_init(void); void gfs2_glock_exit(void); -- cgit v1.2.3