diff --git a/fs/gfs2/glock.c b/fs/gfs2/glock.c index a3a24f2e99d2..e7075945b051 100644 --- a/fs/gfs2/glock.c +++ b/fs/gfs2/glock.c @@ -54,7 +54,7 @@ struct glock_iter { typedef void (*glock_examiner) (struct gfs2_glock * gl); static int gfs2_dump_lockstate(struct gfs2_sbd *sdp); -static void gfs2_glock_xmote_th(struct gfs2_holder *gh); +static void gfs2_glock_xmote_th(struct gfs2_glock *gl, struct gfs2_holder *gh); static void gfs2_glock_drop_th(struct gfs2_glock *gl); static DECLARE_RWSEM(gfs2_umount_flush_sem); static struct dentry *gfs2_root; @@ -212,7 +212,6 @@ int gfs2_glock_put(struct gfs2_glock *gl) gfs2_assert(sdp, list_empty(&gl->gl_reclaim)); gfs2_assert(sdp, list_empty(&gl->gl_holders)); gfs2_assert(sdp, list_empty(&gl->gl_waiters1)); - gfs2_assert(sdp, list_empty(&gl->gl_waiters2)); gfs2_assert(sdp, list_empty(&gl->gl_waiters3)); glock_free(gl); rv = 1; @@ -399,7 +398,7 @@ void gfs2_holder_reinit(unsigned int state, unsigned flags, struct gfs2_holder * { gh->gh_state = state; gh->gh_flags = flags; - gh->gh_iflags &= 1 << HIF_ALLOCED; + gh->gh_iflags = 0; gh->gh_ip = (unsigned long)__builtin_return_address(0); } @@ -416,54 +415,8 @@ void gfs2_holder_uninit(struct gfs2_holder *gh) gh->gh_ip = 0; } -/** - * gfs2_holder_get - get a struct gfs2_holder structure - * @gl: the glock - * @state: the state we're requesting - * @flags: the modifier flags - * @gfp_flags: - * - * Figure out how big an impact this function has. Either: - * 1) Replace it with a cache of structures hanging off the struct gfs2_sbd - * 2) Leave it like it is - * - * Returns: the holder structure, NULL on ENOMEM - */ - -static struct gfs2_holder *gfs2_holder_get(struct gfs2_glock *gl, - unsigned int state, - int flags, gfp_t gfp_flags) +static void gfs2_holder_wake(struct gfs2_holder *gh) { - struct gfs2_holder *gh; - - gh = kmalloc(sizeof(struct gfs2_holder), gfp_flags); - if (!gh) - return NULL; - - gfs2_holder_init(gl, state, flags, gh); - set_bit(HIF_ALLOCED, &gh->gh_iflags); - gh->gh_ip = (unsigned long)__builtin_return_address(0); - return gh; -} - -/** - * gfs2_holder_put - get rid of a struct gfs2_holder structure - * @gh: the holder structure - * - */ - -static void gfs2_holder_put(struct gfs2_holder *gh) -{ - gfs2_holder_uninit(gh); - kfree(gh); -} - -static void gfs2_holder_dispose_or_wake(struct gfs2_holder *gh) -{ - if (test_bit(HIF_DEALLOC, &gh->gh_iflags)) { - gfs2_holder_put(gh); - return; - } clear_bit(HIF_WAIT, &gh->gh_iflags); smp_mb(); wake_up_bit(&gh->gh_iflags, HIF_WAIT); @@ -529,7 +482,7 @@ static int rq_promote(struct gfs2_holder *gh) gfs2_reclaim_glock(sdp); } - gfs2_glock_xmote_th(gh); + gfs2_glock_xmote_th(gh->gh_gl, gh); spin_lock(&gl->gl_spin); } return 1; @@ -552,7 +505,7 @@ static int rq_promote(struct gfs2_holder *gh) gh->gh_error = 0; set_bit(HIF_HOLDER, &gh->gh_iflags); - gfs2_holder_dispose_or_wake(gh); + gfs2_holder_wake(gh); return 0; } @@ -564,32 +517,24 @@ static int rq_promote(struct gfs2_holder *gh) * Returns: 1 if the queue is blocked */ -static int rq_demote(struct gfs2_holder *gh) +static int rq_demote(struct gfs2_glock *gl) { - struct gfs2_glock *gl = gh->gh_gl; - if (!list_empty(&gl->gl_holders)) return 1; - if (gl->gl_state == gh->gh_state || gl->gl_state == LM_ST_UNLOCKED) { - list_del_init(&gh->gh_list); - gh->gh_error = 0; - spin_unlock(&gl->gl_spin); - gfs2_holder_dispose_or_wake(gh); - spin_lock(&gl->gl_spin); - } else { - gl->gl_req_gh = gh; - set_bit(GLF_LOCK, &gl->gl_flags); - spin_unlock(&gl->gl_spin); - - if (gh->gh_state == LM_ST_UNLOCKED || - gl->gl_state != LM_ST_EXCLUSIVE) - gfs2_glock_drop_th(gl); - else - gfs2_glock_xmote_th(gh); - - spin_lock(&gl->gl_spin); + if (gl->gl_state == gl->gl_demote_state || + gl->gl_state == LM_ST_UNLOCKED) { + clear_bit(GLF_DEMOTE, &gl->gl_flags); + return 0; } + set_bit(GLF_LOCK, &gl->gl_flags); + spin_unlock(&gl->gl_spin); + if (gl->gl_demote_state == LM_ST_UNLOCKED || + gl->gl_state != LM_ST_EXCLUSIVE) + gfs2_glock_drop_th(gl); + else + gfs2_glock_xmote_th(gl, NULL); + spin_lock(&gl->gl_spin); return 0; } @@ -617,16 +562,8 @@ static void run_queue(struct gfs2_glock *gl) else gfs2_assert_warn(gl->gl_sbd, 0); - } else if (!list_empty(&gl->gl_waiters2) && - !test_bit(GLF_SKIP_WAITERS2, &gl->gl_flags)) { - gh = list_entry(gl->gl_waiters2.next, - struct gfs2_holder, gh_list); - - if (test_bit(HIF_DEMOTE, &gh->gh_iflags)) - blocked = rq_demote(gh); - else - gfs2_assert_warn(gl->gl_sbd, 0); - + } else if (test_bit(GLF_DEMOTE, &gl->gl_flags)) { + blocked = rq_demote(gl); } else if (!list_empty(&gl->gl_waiters3)) { gh = list_entry(gl->gl_waiters3.next, struct gfs2_holder, gh_list); @@ -717,50 +654,24 @@ static void gfs2_glmutex_unlock(struct gfs2_glock *gl) } /** - * handle_callback - add a demote request to a lock's queue + * handle_callback - process a demote request * @gl: the glock * @state: the state the caller wants us to change to * - * Note: This may fail sliently if we are out of memory. + * There are only two requests that we are going to see in actual + * practise: LM_ST_SHARED and LM_ST_UNLOCKED */ static void handle_callback(struct gfs2_glock *gl, unsigned int state) { - struct gfs2_holder *gh, *new_gh = NULL; - -restart: spin_lock(&gl->gl_spin); - - list_for_each_entry(gh, &gl->gl_waiters2, gh_list) { - if (test_bit(HIF_DEMOTE, &gh->gh_iflags) && - gl->gl_req_gh != gh) { - if (gh->gh_state != state) - gh->gh_state = LM_ST_UNLOCKED; - goto out; - } + if (test_and_set_bit(GLF_DEMOTE, &gl->gl_flags) == 0) { + gl->gl_demote_state = state; + gl->gl_demote_time = jiffies; + } else if (gl->gl_demote_state != LM_ST_UNLOCKED) { + gl->gl_demote_state = state; } - - if (new_gh) { - list_add_tail(&new_gh->gh_list, &gl->gl_waiters2); - new_gh = NULL; - } else { - spin_unlock(&gl->gl_spin); - - new_gh = gfs2_holder_get(gl, state, LM_FLAG_TRY, GFP_NOFS); - if (!new_gh) - return; - set_bit(HIF_DEMOTE, &new_gh->gh_iflags); - set_bit(HIF_DEALLOC, &new_gh->gh_iflags); - set_bit(HIF_WAIT, &new_gh->gh_iflags); - - goto restart; - } - -out: spin_unlock(&gl->gl_spin); - - if (new_gh) - gfs2_holder_put(new_gh); } /** @@ -820,56 +731,37 @@ static void xmote_bh(struct gfs2_glock *gl, unsigned int ret) /* Deal with each possible exit condition */ - if (!gh) + if (!gh) { gl->gl_stamp = jiffies; - else if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags))) { + if (ret & LM_OUT_CANCELED) + op_done = 0; + else + clear_bit(GLF_DEMOTE, &gl->gl_flags); + } else { spin_lock(&gl->gl_spin); list_del_init(&gh->gh_list); gh->gh_error = -EIO; - spin_unlock(&gl->gl_spin); - } else if (test_bit(HIF_DEMOTE, &gh->gh_iflags)) { - spin_lock(&gl->gl_spin); - list_del_init(&gh->gh_list); - if (gl->gl_state == gh->gh_state || - gl->gl_state == LM_ST_UNLOCKED) { - gh->gh_error = 0; - } else { - if (gfs2_assert_warn(sdp, gh->gh_flags & - (LM_FLAG_TRY | LM_FLAG_TRY_1CB)) == -1) - fs_warn(sdp, "ret = 0x%.8X\n", ret); - gh->gh_error = GLR_TRYFAILED; - } - spin_unlock(&gl->gl_spin); - - if (ret & LM_OUT_CANCELED) - handle_callback(gl, LM_ST_UNLOCKED); - - } else if (ret & LM_OUT_CANCELED) { - spin_lock(&gl->gl_spin); - list_del_init(&gh->gh_list); + if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags))) + goto out; gh->gh_error = GLR_CANCELED; - spin_unlock(&gl->gl_spin); - - } else if (relaxed_state_ok(gl->gl_state, gh->gh_state, gh->gh_flags)) { - spin_lock(&gl->gl_spin); - list_move_tail(&gh->gh_list, &gl->gl_holders); - gh->gh_error = 0; - set_bit(HIF_HOLDER, &gh->gh_iflags); - spin_unlock(&gl->gl_spin); - - set_bit(HIF_FIRST, &gh->gh_iflags); - - op_done = 0; - - } else if (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB)) { - spin_lock(&gl->gl_spin); - list_del_init(&gh->gh_list); + if (ret & LM_OUT_CANCELED) + goto out; + if (relaxed_state_ok(gl->gl_state, gh->gh_state, gh->gh_flags)) { + list_add_tail(&gh->gh_list, &gl->gl_holders); + gh->gh_error = 0; + set_bit(HIF_HOLDER, &gh->gh_iflags); + set_bit(HIF_FIRST, &gh->gh_iflags); + op_done = 0; + goto out; + } gh->gh_error = GLR_TRYFAILED; - spin_unlock(&gl->gl_spin); - - } else { + if (gh->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB)) + goto out; + gh->gh_error = -EINVAL; if (gfs2_assert_withdraw(sdp, 0) == -1) fs_err(sdp, "ret = 0x%.8X\n", ret); +out: + spin_unlock(&gl->gl_spin); } if (glops->go_xmote_bh) @@ -887,7 +779,7 @@ static void xmote_bh(struct gfs2_glock *gl, unsigned int ret) gfs2_glock_put(gl); if (gh) - gfs2_holder_dispose_or_wake(gh); + gfs2_holder_wake(gh); } /** @@ -898,12 +790,11 @@ static void xmote_bh(struct gfs2_glock *gl, unsigned int ret) * */ -void gfs2_glock_xmote_th(struct gfs2_holder *gh) +void gfs2_glock_xmote_th(struct gfs2_glock *gl, struct gfs2_holder *gh) { - struct gfs2_glock *gl = gh->gh_gl; struct gfs2_sbd *sdp = gl->gl_sbd; - int flags = gh->gh_flags; - unsigned state = gh->gh_state; + int flags = gh ? gh->gh_flags : 0; + unsigned state = gh ? gh->gh_state : gl->gl_demote_state; const struct gfs2_glock_operations *glops = gl->gl_ops; int lck_flags = flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB | LM_FLAG_NOEXP | LM_FLAG_ANY | @@ -953,6 +844,7 @@ static void drop_bh(struct gfs2_glock *gl, unsigned int ret) gfs2_assert_warn(sdp, !ret); state_change(gl, LM_ST_UNLOCKED); + clear_bit(GLF_DEMOTE, &gl->gl_flags); if (glops->go_inval) glops->go_inval(gl, DIO_METADATA); @@ -974,7 +866,7 @@ static void drop_bh(struct gfs2_glock *gl, unsigned int ret) gfs2_glock_put(gl); if (gh) - gfs2_holder_dispose_or_wake(gh); + gfs2_holder_wake(gh); } /** @@ -1291,9 +1183,8 @@ void gfs2_glock_dq(struct gfs2_holder *gh) if (glops->go_unlock) glops->go_unlock(gh); - gl->gl_stamp = jiffies; - spin_lock(&gl->gl_spin); + gl->gl_stamp = jiffies; } clear_bit(GLF_LOCK, &gl->gl_flags); @@ -1981,16 +1872,16 @@ static int dump_glock(struct glock_iter *gi, struct gfs2_glock *gl) if (error) goto out; } - list_for_each_entry(gh, &gl->gl_waiters2, gh_list) { - error = dump_holder(gi, "Waiter2", gh); - if (error) - goto out; - } list_for_each_entry(gh, &gl->gl_waiters3, gh_list) { error = dump_holder(gi, "Waiter3", gh); if (error) goto out; } + if (test_bit(GLF_DEMOTE, &gl->gl_flags)) { + print_dbg(gi, " Demotion req to state %u (%llu uS ago)\n", + gl->gl_demote_state, + (u64)(jiffies - gl->gl_demote_time)*1000000/HZ); + } if (gl->gl_ops == &gfs2_inode_glops && gl->gl_object) { if (!test_bit(GLF_LOCK, &gl->gl_flags) && list_empty(&gl->gl_holders)) { diff --git a/fs/gfs2/glock.h b/fs/gfs2/glock.h index d7cef7408728..5e662eadc6f2 100644 --- a/fs/gfs2/glock.h +++ b/fs/gfs2/glock.h @@ -67,7 +67,7 @@ static inline int gfs2_glock_is_blocking(struct gfs2_glock *gl) { int ret; spin_lock(&gl->gl_spin); - ret = !list_empty(&gl->gl_waiters2) || !list_empty(&gl->gl_waiters3); + ret = test_bit(GLF_DEMOTE, &gl->gl_flags) || !list_empty(&gl->gl_waiters3); spin_unlock(&gl->gl_spin); return ret; } diff --git a/fs/gfs2/incore.h b/fs/gfs2/incore.h index 7555261d911f..9c125823d760 100644 --- a/fs/gfs2/incore.h +++ b/fs/gfs2/incore.h @@ -115,11 +115,8 @@ enum { /* Actions */ HIF_MUTEX = 0, HIF_PROMOTE = 1, - HIF_DEMOTE = 2, /* States */ - HIF_ALLOCED = 4, - HIF_DEALLOC = 5, HIF_HOLDER = 6, HIF_FIRST = 7, HIF_ABORTED = 9, @@ -142,8 +139,8 @@ struct gfs2_holder { enum { GLF_LOCK = 1, GLF_STICKY = 2, + GLF_DEMOTE = 3, GLF_DIRTY = 5, - GLF_SKIP_WAITERS2 = 6, }; struct gfs2_glock { @@ -156,11 +153,12 @@ struct gfs2_glock { unsigned int gl_state; unsigned int gl_hash; + unsigned int gl_demote_state; /* state requested by remote node */ + unsigned long gl_demote_time; /* time of first demote request */ struct task_struct *gl_owner; unsigned long gl_ip; struct list_head gl_holders; struct list_head gl_waiters1; /* HIF_MUTEX */ - struct list_head gl_waiters2; /* HIF_DEMOTE */ struct list_head gl_waiters3; /* HIF_PROMOTE */ const struct gfs2_glock_operations *gl_ops; diff --git a/fs/gfs2/main.c b/fs/gfs2/main.c index 218395371dbe..c4bb374eaf92 100644 --- a/fs/gfs2/main.c +++ b/fs/gfs2/main.c @@ -45,7 +45,6 @@ static void gfs2_init_glock_once(void *foo, struct kmem_cache *cachep, unsigned spin_lock_init(&gl->gl_spin); INIT_LIST_HEAD(&gl->gl_holders); INIT_LIST_HEAD(&gl->gl_waiters1); - INIT_LIST_HEAD(&gl->gl_waiters2); INIT_LIST_HEAD(&gl->gl_waiters3); gl->gl_lvb = NULL; atomic_set(&gl->gl_lvb_count, 0); diff --git a/fs/gfs2/ops_super.c b/fs/gfs2/ops_super.c index b89999d3a767..485ce3d49923 100644 --- a/fs/gfs2/ops_super.c +++ b/fs/gfs2/ops_super.c @@ -283,6 +283,31 @@ static int gfs2_remount_fs(struct super_block *sb, int *flags, char *data) return error; } +/** + * gfs2_drop_inode - Drop an inode (test for remote unlink) + * @inode: The inode to drop + * + * If we've received a callback on an iopen lock then its because a + * remote node tried to deallocate the inode but failed due to this node + * still having the inode open. Here we mark the link count zero + * since we know that it must have reached zero if the GLF_DEMOTE flag + * is set on the iopen glock. If we didn't do a disk read since the + * remote node removed the final link then we might otherwise miss + * this event. This check ensures that this node will deallocate the + * inode's blocks, or alternatively pass the baton on to another + * node for later deallocation. + */ +static void gfs2_drop_inode(struct inode *inode) +{ + if (inode->i_private && inode->i_nlink) { + struct gfs2_inode *ip = GFS2_I(inode); + struct gfs2_glock *gl = ip->i_iopen_gh.gh_gl; + if (gl && test_bit(GLF_DEMOTE, &gl->gl_flags)) + clear_nlink(inode); + } + generic_drop_inode(inode); +} + /** * gfs2_clear_inode - Deallocate an inode when VFS is done with it * @inode: The VFS inode @@ -441,7 +466,7 @@ out_unlock: out_uninit: gfs2_holder_uninit(&ip->i_iopen_gh); gfs2_glock_dq_uninit(&gh); - if (error) + if (error && error != GLR_TRYFAILED) fs_warn(sdp, "gfs2_delete_inode: %d\n", error); out: truncate_inode_pages(&inode->i_data, 0); @@ -481,6 +506,7 @@ const struct super_operations gfs2_super_ops = { .statfs = gfs2_statfs, .remount_fs = gfs2_remount_fs, .clear_inode = gfs2_clear_inode, + .drop_inode = gfs2_drop_inode, .show_options = gfs2_show_options, };