From f057f6cdf64175db1151b1f5d110e29904f119a1 Mon Sep 17 00:00:00 2001 From: Steven Whitehouse Date: Mon, 12 Jan 2009 10:43:39 +0000 Subject: GFS2: Merge lock_dlm module into GFS2 This is the big patch that I've been working on for some time now. There are many reasons for wanting to make this change such as: o Reducing overhead by eliminating duplicated fields between structures o Simplifcation of the code (reduces the code size by a fair bit) o The locking interface is now the DLM interface itself as proposed some time ago. o Fewer lookups of glocks when processing replies from the DLM o Fewer memory allocations/deallocations for each glock o Scope to do further optimisations in the future (but this patch is more than big enough for now!) Please note that (a) this patch relates to the lock_dlm module and not the DLM itself, that is still a separate module; and (b) that we retain the ability to build GFS2 as a standalone single node filesystem with out requiring the DLM. This patch needs a lot of testing, hence my keeping it I restarted my -git tree after the last merge window. That way, this has the maximum exposure before its merged. This is (modulo a few minor bug fixes) the same patch that I've been posting on and off the the last three months and its passed a number of different tests so far. Signed-off-by: Steven Whitehouse --- fs/gfs2/glock.c | 249 +++++++++++++++++--------------------------------------- 1 file changed, 75 insertions(+), 174 deletions(-) (limited to 'fs/gfs2/glock.c') diff --git a/fs/gfs2/glock.c b/fs/gfs2/glock.c index 6b983aef785d..cd200a564c79 100644 --- a/fs/gfs2/glock.c +++ b/fs/gfs2/glock.c @@ -10,7 +10,6 @@ #include #include #include -#include #include #include #include @@ -18,7 +17,6 @@ #include #include #include -#include #include #include #include @@ -155,13 +153,10 @@ static void glock_free(struct gfs2_glock *gl) struct gfs2_sbd *sdp = gl->gl_sbd; struct inode *aspace = gl->gl_aspace; - if (sdp->sd_lockstruct.ls_ops->lm_put_lock) - sdp->sd_lockstruct.ls_ops->lm_put_lock(gl->gl_lock); - if (aspace) gfs2_aspace_put(aspace); - kmem_cache_free(gfs2_glock_cachep, gl); + sdp->sd_lockstruct.ls_ops->lm_put_lock(gfs2_glock_cachep, gl); } /** @@ -211,7 +206,6 @@ int gfs2_glock_put(struct gfs2_glock *gl) atomic_dec(&lru_count); } spin_unlock(&lru_lock); - GLOCK_BUG_ON(gl, gl->gl_state != LM_ST_UNLOCKED); GLOCK_BUG_ON(gl, !list_empty(&gl->gl_lru)); GLOCK_BUG_ON(gl, !list_empty(&gl->gl_holders)); glock_free(gl); @@ -255,27 +249,6 @@ static struct gfs2_glock *search_bucket(unsigned int hash, return NULL; } -/** - * gfs2_glock_find() - Find glock by lock number - * @sdp: The GFS2 superblock - * @name: The lock name - * - * Returns: NULL, or the struct gfs2_glock with the requested number - */ - -static struct gfs2_glock *gfs2_glock_find(const struct gfs2_sbd *sdp, - const struct lm_lockname *name) -{ - unsigned int hash = gl_hash(sdp, name); - struct gfs2_glock *gl; - - read_lock(gl_lock_addr(hash)); - gl = search_bucket(hash, sdp, name); - read_unlock(gl_lock_addr(hash)); - - return gl; -} - /** * may_grant - check if its ok to grant a new lock * @gl: The glock @@ -523,7 +496,7 @@ out_locked: } static unsigned int gfs2_lm_lock(struct gfs2_sbd *sdp, void *lock, - unsigned int cur_state, unsigned int req_state, + unsigned int req_state, unsigned int flags) { int ret = LM_OUT_ERROR; @@ -532,7 +505,7 @@ static unsigned int gfs2_lm_lock(struct gfs2_sbd *sdp, void *lock, return req_state == LM_ST_UNLOCKED ? 0 : req_state; if (likely(!test_bit(SDF_SHUTDOWN, &sdp->sd_flags))) - ret = sdp->sd_lockstruct.ls_ops->lm_lock(lock, cur_state, + ret = sdp->sd_lockstruct.ls_ops->lm_lock(lock, req_state, flags); return ret; } @@ -575,7 +548,7 @@ __acquires(&gl->gl_spin) gl->gl_state == LM_ST_DEFERRED) && !(lck_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB))) lck_flags |= LM_FLAG_TRY_1CB; - ret = gfs2_lm_lock(sdp, gl->gl_lock, gl->gl_state, target, lck_flags); + ret = gfs2_lm_lock(sdp, gl, target, lck_flags); if (!(ret & LM_OUT_ASYNC)) { finish_xmote(gl, ret); @@ -681,18 +654,6 @@ static void glock_work_func(struct work_struct *work) gfs2_glock_put(gl); } -static int gfs2_lm_get_lock(struct gfs2_sbd *sdp, struct lm_lockname *name, - void **lockp) -{ - int error = -EIO; - if (!sdp->sd_lockstruct.ls_ops->lm_get_lock) - return 0; - if (likely(!test_bit(SDF_SHUTDOWN, &sdp->sd_flags))) - error = sdp->sd_lockstruct.ls_ops->lm_get_lock( - sdp->sd_lockstruct.ls_lockspace, name, lockp); - return error; -} - /** * gfs2_glock_get() - Get a glock, or create one if one doesn't exist * @sdp: The GFS2 superblock @@ -736,6 +697,9 @@ int gfs2_glock_get(struct gfs2_sbd *sdp, u64 number, gl->gl_demote_state = LM_ST_EXCLUSIVE; gl->gl_hash = hash; gl->gl_ops = glops; + snprintf(gl->gl_strname, GDLM_STRNAME_BYTES, "%8x%16llx", name.ln_type, (unsigned long long)number); + memset(&gl->gl_lksb, 0, sizeof(struct dlm_lksb)); + gl->gl_lksb.sb_lvbptr = gl->gl_lvb; gl->gl_stamp = jiffies; gl->gl_tchange = jiffies; gl->gl_object = NULL; @@ -753,10 +717,6 @@ int gfs2_glock_get(struct gfs2_sbd *sdp, u64 number, } } - error = gfs2_lm_get_lock(sdp, &name, &gl->gl_lock); - if (error) - goto fail_aspace; - write_lock(gl_lock_addr(hash)); tmp = search_bucket(hash, sdp, &name); if (tmp) { @@ -772,9 +732,6 @@ int gfs2_glock_get(struct gfs2_sbd *sdp, u64 number, return 0; -fail_aspace: - if (gl->gl_aspace) - gfs2_aspace_put(gl->gl_aspace); fail: kmem_cache_free(gfs2_glock_cachep, gl); return error; @@ -966,7 +923,7 @@ do_cancel: if (!(gh->gh_flags & LM_FLAG_PRIORITY)) { spin_unlock(&gl->gl_spin); if (sdp->sd_lockstruct.ls_ops->lm_cancel) - sdp->sd_lockstruct.ls_ops->lm_cancel(gl->gl_lock); + sdp->sd_lockstruct.ls_ops->lm_cancel(gl); spin_lock(&gl->gl_spin); } return; @@ -1240,70 +1197,13 @@ void gfs2_glock_dq_uninit_m(unsigned int num_gh, struct gfs2_holder *ghs) gfs2_glock_dq_uninit(&ghs[x]); } -static int gfs2_lm_hold_lvb(struct gfs2_sbd *sdp, void *lock, char **lvbp) +void gfs2_glock_cb(struct gfs2_glock *gl, unsigned int state) { - int error = -EIO; - if (!sdp->sd_lockstruct.ls_ops->lm_hold_lvb) - return 0; - if (likely(!test_bit(SDF_SHUTDOWN, &sdp->sd_flags))) - error = sdp->sd_lockstruct.ls_ops->lm_hold_lvb(lock, lvbp); - return error; -} - -/** - * gfs2_lvb_hold - attach a LVB from a glock - * @gl: The glock in question - * - */ - -int gfs2_lvb_hold(struct gfs2_glock *gl) -{ - int error; - - if (!atomic_read(&gl->gl_lvb_count)) { - error = gfs2_lm_hold_lvb(gl->gl_sbd, gl->gl_lock, &gl->gl_lvb); - if (error) - return error; - gfs2_glock_hold(gl); - } - atomic_inc(&gl->gl_lvb_count); - - return 0; -} - -/** - * gfs2_lvb_unhold - detach a LVB from a glock - * @gl: The glock in question - * - */ - -void gfs2_lvb_unhold(struct gfs2_glock *gl) -{ - struct gfs2_sbd *sdp = gl->gl_sbd; - - gfs2_glock_hold(gl); - gfs2_assert(gl->gl_sbd, atomic_read(&gl->gl_lvb_count) > 0); - if (atomic_dec_and_test(&gl->gl_lvb_count)) { - if (sdp->sd_lockstruct.ls_ops->lm_unhold_lvb) - sdp->sd_lockstruct.ls_ops->lm_unhold_lvb(gl->gl_lock, gl->gl_lvb); - gl->gl_lvb = NULL; - gfs2_glock_put(gl); - } - gfs2_glock_put(gl); -} - -static void blocking_cb(struct gfs2_sbd *sdp, struct lm_lockname *name, - unsigned int state) -{ - struct gfs2_glock *gl; unsigned long delay = 0; unsigned long holdtime; unsigned long now = jiffies; - gl = gfs2_glock_find(sdp, name); - if (!gl) - return; - + gfs2_glock_hold(gl); holdtime = gl->gl_tchange + gl->gl_ops->go_min_hold_time; if (time_before(now, holdtime)) delay = holdtime - now; @@ -1317,74 +1217,37 @@ static void blocking_cb(struct gfs2_sbd *sdp, struct lm_lockname *name, gfs2_glock_put(gl); } -static void gfs2_jdesc_make_dirty(struct gfs2_sbd *sdp, unsigned int jid) -{ - struct gfs2_jdesc *jd; - - spin_lock(&sdp->sd_jindex_spin); - list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) { - if (jd->jd_jid != jid) - continue; - jd->jd_dirty = 1; - break; - } - spin_unlock(&sdp->sd_jindex_spin); -} - /** - * gfs2_glock_cb - Callback used by locking module - * @sdp: Pointer to the superblock - * @type: Type of callback - * @data: Type dependent data pointer + * gfs2_glock_complete - Callback used by locking + * @gl: Pointer to the glock + * @ret: The return value from the dlm * - * Called by the locking module when it wants to tell us something. - * Either we need to drop a lock, one of our ASYNC requests completed, or - * a journal from another client needs to be recovered. */ -void gfs2_glock_cb(void *cb_data, unsigned int type, void *data) +void gfs2_glock_complete(struct gfs2_glock *gl, int ret) { - struct gfs2_sbd *sdp = cb_data; - - switch (type) { - case LM_CB_NEED_E: - blocking_cb(sdp, data, LM_ST_UNLOCKED); - return; - - case LM_CB_NEED_D: - blocking_cb(sdp, data, LM_ST_DEFERRED); - return; - - case LM_CB_NEED_S: - blocking_cb(sdp, data, LM_ST_SHARED); - return; - - case LM_CB_ASYNC: { - struct lm_async_cb *async = data; - struct gfs2_glock *gl; - - down_read(&gfs2_umount_flush_sem); - gl = gfs2_glock_find(sdp, &async->lc_name); - if (gfs2_assert_warn(sdp, gl)) + struct lm_lockstruct *ls = &gl->gl_sbd->sd_lockstruct; + down_read(&gfs2_umount_flush_sem); + gl->gl_reply = ret; + if (unlikely(test_bit(DFL_BLOCK_LOCKS, &ls->ls_flags))) { + struct gfs2_holder *gh; + spin_lock(&gl->gl_spin); + gh = find_first_waiter(gl); + if ((!(gh && (gh->gh_flags & LM_FLAG_NOEXP)) && + (gl->gl_target != LM_ST_UNLOCKED)) || + ((ret & ~LM_OUT_ST_MASK) != 0)) + set_bit(GLF_FROZEN, &gl->gl_flags); + spin_unlock(&gl->gl_spin); + if (test_bit(GLF_FROZEN, &gl->gl_flags)) { + up_read(&gfs2_umount_flush_sem); return; - gl->gl_reply = async->lc_ret; - set_bit(GLF_REPLY_PENDING, &gl->gl_flags); - if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0) - gfs2_glock_put(gl); - up_read(&gfs2_umount_flush_sem); - return; - } - - case LM_CB_NEED_RECOVERY: - gfs2_jdesc_make_dirty(sdp, *(unsigned int *)data); - if (sdp->sd_recoverd_process) - wake_up_process(sdp->sd_recoverd_process); - return; - - default: - gfs2_assert_warn(sdp, 0); - return; + } } + set_bit(GLF_REPLY_PENDING, &gl->gl_flags); + gfs2_glock_hold(gl); + if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0) + gfs2_glock_put(gl); + up_read(&gfs2_umount_flush_sem); } /** @@ -1515,6 +1378,27 @@ out: return has_entries; } + +/** + * thaw_glock - thaw out a glock which has an unprocessed reply waiting + * @gl: The glock to thaw + * + * N.B. When we freeze a glock, we leave a ref to the glock outstanding, + * so this has to result in the ref count being dropped by one. + */ + +static void thaw_glock(struct gfs2_glock *gl) +{ + if (!test_and_clear_bit(GLF_FROZEN, &gl->gl_flags)) + return; + down_read(&gfs2_umount_flush_sem); + set_bit(GLF_REPLY_PENDING, &gl->gl_flags); + gfs2_glock_hold(gl); + if (queue_delayed_work(glock_workqueue, &gl->gl_work, 0) == 0) + gfs2_glock_put(gl); + up_read(&gfs2_umount_flush_sem); +} + /** * clear_glock - look at a glock and see if we can free it from glock cache * @gl: the glock to look at @@ -1539,6 +1423,20 @@ static void clear_glock(struct gfs2_glock *gl) gfs2_glock_put(gl); } +/** + * gfs2_glock_thaw - Thaw any frozen glocks + * @sdp: The super block + * + */ + +void gfs2_glock_thaw(struct gfs2_sbd *sdp) +{ + unsigned x; + + for (x = 0; x < GFS2_GL_HASH_SIZE; x++) + examine_bucket(thaw_glock, sdp, x); +} + /** * gfs2_gl_hash_clear - Empty out the glock hash table * @sdp: the filesystem @@ -1619,7 +1517,7 @@ static const char *hflags2str(char *buf, unsigned flags, unsigned long iflags) if (flags & LM_FLAG_NOEXP) *p++ = 'e'; if (flags & LM_FLAG_ANY) - *p++ = 'a'; + *p++ = 'A'; if (flags & LM_FLAG_PRIORITY) *p++ = 'p'; if (flags & GL_ASYNC) @@ -1683,6 +1581,10 @@ static const char *gflags2str(char *buf, const unsigned long *gflags) *p++ = 'i'; if (test_bit(GLF_REPLY_PENDING, gflags)) *p++ = 'r'; + if (test_bit(GLF_INITIAL, gflags)) + *p++ = 'i'; + if (test_bit(GLF_FROZEN, gflags)) + *p++ = 'F'; *p = 0; return buf; } @@ -1717,14 +1619,13 @@ static int __dump_glock(struct seq_file *seq, const struct gfs2_glock *gl) dtime *= 1000000/HZ; /* demote time in uSec */ if (!test_bit(GLF_DEMOTE, &gl->gl_flags)) dtime = 0; - gfs2_print_dbg(seq, "G: s:%s n:%u/%llu f:%s t:%s d:%s/%llu l:%d a:%d r:%d\n", + gfs2_print_dbg(seq, "G: s:%s n:%u/%llu f:%s t:%s d:%s/%llu a:%d r:%d\n", state2str(gl->gl_state), gl->gl_name.ln_type, (unsigned long long)gl->gl_name.ln_number, gflags2str(gflags_buf, &gl->gl_flags), state2str(gl->gl_target), state2str(gl->gl_demote_state), dtime, - atomic_read(&gl->gl_lvb_count), atomic_read(&gl->gl_ail_count), atomic_read(&gl->gl_ref)); -- cgit v1.2.3