From 6df9f9a253c7dc9f8ed18bf89d762de350a31813 Mon Sep 17 00:00:00 2001 From: Andreas Gruenbacher Date: Fri, 17 Jun 2016 07:31:27 -0500 Subject: [PATCH] gfs2: Lock holder cleanup Make the code more readable by cleaning up the different ways of initializing lock holders and checking for initialized lock holders: mark lock holders as uninitialized by setting the holder's glock to NULL (gfs2_holder_mark_uninitialized) instead of zeroing out the entire object or using a separate flag. Recognize initialized holders by their non-NULL glock (gfs2_holder_initialized). Don't zero out holder objects which are immeditiately initialized via gfs2_holder_init or gfs2_glock_nq_init. Signed-off-by: Andreas Gruenbacher Signed-off-by: Bob Peterson --- fs/gfs2/dentry.c | 2 +- fs/gfs2/file.c | 2 +- fs/gfs2/glock.c | 2 +- fs/gfs2/glock.h | 10 ++++++++++ fs/gfs2/inode.c | 33 +++++++++++++++------------------ fs/gfs2/main.c | 2 +- fs/gfs2/quota.c | 2 +- fs/gfs2/rgrp.c | 4 ++-- fs/gfs2/super.c | 24 ++++++++++++++---------- 9 files changed, 46 insertions(+), 35 deletions(-) diff --git a/fs/gfs2/dentry.c b/fs/gfs2/dentry.c index 30822b148f3e..5173b98ca036 100644 --- a/fs/gfs2/dentry.c +++ b/fs/gfs2/dentry.c @@ -117,7 +117,7 @@ static int gfs2_dentry_delete(const struct dentry *dentry) return 0; ginode = GFS2_I(d_inode(dentry)); - if (!ginode->i_iopen_gh.gh_gl) + if (!gfs2_holder_initialized(&ginode->i_iopen_gh)) return 0; if (test_bit(GLF_DEMOTE, &ginode->i_iopen_gh.gh_gl->gl_flags)) diff --git a/fs/gfs2/file.c b/fs/gfs2/file.c index e0f98e483aec..320e65e61938 100644 --- a/fs/gfs2/file.c +++ b/fs/gfs2/file.c @@ -1098,7 +1098,7 @@ static void do_unflock(struct file *file, struct file_lock *fl) mutex_lock(&fp->f_fl_mutex); locks_lock_file_wait(file, fl); - if (fl_gh->gh_gl) { + if (gfs2_holder_initialized(fl_gh)) { gfs2_glock_dq(fl_gh); gfs2_holder_uninit(fl_gh); } diff --git a/fs/gfs2/glock.c b/fs/gfs2/glock.c index 1138a6131c61..3a90b2b5b9bb 100644 --- a/fs/gfs2/glock.c +++ b/fs/gfs2/glock.c @@ -801,7 +801,7 @@ void gfs2_holder_uninit(struct gfs2_holder *gh) { put_pid(gh->gh_owner_pid); gfs2_glock_put(gh->gh_gl); - gh->gh_gl = NULL; + gfs2_holder_mark_uninitialized(gh); gh->gh_ip = 0; } diff --git a/fs/gfs2/glock.h b/fs/gfs2/glock.h index 46ab67fc16da..ab1ef322f7a5 100644 --- a/fs/gfs2/glock.h +++ b/fs/gfs2/glock.h @@ -247,4 +247,14 @@ extern void gfs2_unregister_debugfs(void); extern const struct lm_lockops gfs2_dlm_ops; +static inline void gfs2_holder_mark_uninitialized(struct gfs2_holder *gh) +{ + gh->gh_gl = NULL; +} + +static inline bool gfs2_holder_initialized(struct gfs2_holder *gh) +{ + return gh->gh_gl; +} + #endif /* __GLOCK_DOT_H__ */ diff --git a/fs/gfs2/inode.c b/fs/gfs2/inode.c index 481b6496727d..de54d605cd09 100644 --- a/fs/gfs2/inode.c +++ b/fs/gfs2/inode.c @@ -127,9 +127,9 @@ struct inode *gfs2_inode_lookup(struct super_block *sb, unsigned int type, struct gfs2_inode *ip; struct gfs2_glock *io_gl = NULL; struct gfs2_holder i_gh; - bool unlock = false; int error; + gfs2_holder_mark_uninitialized(&i_gh); inode = gfs2_iget(sb, no_addr); if (!inode) return ERR_PTR(-ENOMEM); @@ -159,7 +159,6 @@ struct inode *gfs2_inode_lookup(struct super_block *sb, unsigned int type, GL_SKIP, &i_gh); if (error) goto fail_put; - unlock = true; if (blktype != GFS2_BLKST_FREE) { error = gfs2_check_blk_type(sdp, no_addr, @@ -191,7 +190,7 @@ struct inode *gfs2_inode_lookup(struct super_block *sb, unsigned int type, unlock_new_inode(inode); } - if (unlock) + if (gfs2_holder_initialized(&i_gh)) gfs2_glock_dq_uninit(&i_gh); return inode; @@ -203,7 +202,7 @@ struct inode *gfs2_inode_lookup(struct super_block *sb, unsigned int type, fail_put: if (io_gl) gfs2_glock_put(io_gl); - if (unlock) + if (gfs2_holder_initialized(&i_gh)) gfs2_glock_dq_uninit(&i_gh); ip->i_gl->gl_object = NULL; fail: @@ -281,8 +280,8 @@ struct inode *gfs2_lookupi(struct inode *dir, const struct qstr *name, struct gfs2_holder d_gh; int error = 0; struct inode *inode = NULL; - int unlock = 0; + gfs2_holder_mark_uninitialized(&d_gh); if (!name->len || name->len > GFS2_FNAMESIZE) return ERR_PTR(-ENAMETOOLONG); @@ -297,7 +296,6 @@ struct inode *gfs2_lookupi(struct inode *dir, const struct qstr *name, error = gfs2_glock_nq_init(dip->i_gl, LM_ST_SHARED, 0, &d_gh); if (error) return ERR_PTR(error); - unlock = 1; } if (!is_root) { @@ -310,7 +308,7 @@ struct inode *gfs2_lookupi(struct inode *dir, const struct qstr *name, if (IS_ERR(inode)) error = PTR_ERR(inode); out: - if (unlock) + if (gfs2_holder_initialized(&d_gh)) gfs2_glock_dq_uninit(&d_gh); if (error == -ENOENT) return NULL; @@ -1354,7 +1352,7 @@ static int gfs2_rename(struct inode *odir, struct dentry *odentry, struct gfs2_inode *ip = GFS2_I(d_inode(odentry)); struct gfs2_inode *nip = NULL; struct gfs2_sbd *sdp = GFS2_SB(odir); - struct gfs2_holder ghs[5], r_gh = { .gh_gl = NULL, }; + struct gfs2_holder ghs[5], r_gh; struct gfs2_rgrpd *nrgd; unsigned int num_gh; int dir_rename = 0; @@ -1362,6 +1360,7 @@ static int gfs2_rename(struct inode *odir, struct dentry *odentry, unsigned int x; int error; + gfs2_holder_mark_uninitialized(&r_gh); if (d_really_is_positive(ndentry)) { nip = GFS2_I(d_inode(ndentry)); if (ip == nip) @@ -1551,7 +1550,7 @@ static int gfs2_rename(struct inode *odir, struct dentry *odentry, gfs2_holder_uninit(ghs + x); } out_gunlock_r: - if (r_gh.gh_gl) + if (gfs2_holder_initialized(&r_gh)) gfs2_glock_dq_uninit(&r_gh); out: return error; @@ -1577,13 +1576,14 @@ static int gfs2_exchange(struct inode *odir, struct dentry *odentry, struct gfs2_inode *oip = GFS2_I(odentry->d_inode); struct gfs2_inode *nip = GFS2_I(ndentry->d_inode); struct gfs2_sbd *sdp = GFS2_SB(odir); - struct gfs2_holder ghs[5], r_gh = { .gh_gl = NULL, }; + struct gfs2_holder ghs[5], r_gh; unsigned int num_gh; unsigned int x; umode_t old_mode = oip->i_inode.i_mode; umode_t new_mode = nip->i_inode.i_mode; int error; + gfs2_holder_mark_uninitialized(&r_gh); error = gfs2_rindex_update(sdp); if (error) return error; @@ -1691,7 +1691,7 @@ static int gfs2_exchange(struct inode *odir, struct dentry *odentry, gfs2_holder_uninit(ghs + x); } out_gunlock_r: - if (r_gh.gh_gl) + if (gfs2_holder_initialized(&r_gh)) gfs2_glock_dq_uninit(&r_gh); out: return error; @@ -1788,9 +1788,8 @@ int gfs2_permission(struct inode *inode, int mask) struct gfs2_inode *ip; struct gfs2_holder i_gh; int error; - int unlock = 0; - + gfs2_holder_mark_uninitialized(&i_gh); ip = GFS2_I(inode); if (gfs2_glock_is_locked_by_me(ip->i_gl) == NULL) { if (mask & MAY_NOT_BLOCK) @@ -1798,14 +1797,13 @@ int gfs2_permission(struct inode *inode, int mask) error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, &i_gh); if (error) return error; - unlock = 1; } if ((mask & MAY_WRITE) && IS_IMMUTABLE(inode)) error = -EACCES; else error = generic_permission(inode, mask); - if (unlock) + if (gfs2_holder_initialized(&i_gh)) gfs2_glock_dq_uninit(&i_gh); return error; @@ -1977,17 +1975,16 @@ static int gfs2_getattr(struct vfsmount *mnt, struct dentry *dentry, struct gfs2_inode *ip = GFS2_I(inode); struct gfs2_holder gh; int error; - int unlock = 0; + gfs2_holder_mark_uninitialized(&gh); if (gfs2_glock_is_locked_by_me(ip->i_gl) == NULL) { error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, &gh); if (error) return error; - unlock = 1; } generic_fillattr(inode, stat); - if (unlock) + if (gfs2_holder_initialized(&gh)) gfs2_glock_dq_uninit(&gh); return 0; diff --git a/fs/gfs2/main.c b/fs/gfs2/main.c index 615f67581cc2..74fd0139e6c2 100644 --- a/fs/gfs2/main.c +++ b/fs/gfs2/main.c @@ -45,7 +45,7 @@ static void gfs2_init_inode_once(void *foo) memset(&ip->i_res, 0, sizeof(ip->i_res)); RB_CLEAR_NODE(&ip->i_res.rs_node); ip->i_hash_cache = NULL; - ip->i_iopen_gh.gh_gl = NULL; + gfs2_holder_mark_uninitialized(&ip->i_iopen_gh); } static void gfs2_init_glock_once(void *foo) diff --git a/fs/gfs2/quota.c b/fs/gfs2/quota.c index ce7d69a2fdc0..6c657b202501 100644 --- a/fs/gfs2/quota.c +++ b/fs/gfs2/quota.c @@ -883,7 +883,7 @@ static int do_sync(unsigned int num_qd, struct gfs2_quota_data **qda) gfs2_write_calc_reserv(ip, sizeof(struct gfs2_quota), &data_blocks, &ind_blocks); - ghs = kcalloc(num_qd, sizeof(struct gfs2_holder), GFP_NOFS); + ghs = kmalloc(num_qd * sizeof(struct gfs2_holder), GFP_NOFS); if (!ghs) return -ENOMEM; diff --git a/fs/gfs2/rgrp.c b/fs/gfs2/rgrp.c index 960aaf43d665..fba38ca94135 100644 --- a/fs/gfs2/rgrp.c +++ b/fs/gfs2/rgrp.c @@ -2100,7 +2100,7 @@ void gfs2_inplace_release(struct gfs2_inode *ip) { struct gfs2_blkreserv *rs = &ip->i_res; - if (rs->rs_rgd_gh.gh_gl) + if (gfs2_holder_initialized(&rs->rs_rgd_gh)) gfs2_glock_dq_uninit(&rs->rs_rgd_gh); } @@ -2600,7 +2600,7 @@ void gfs2_rlist_alloc(struct gfs2_rgrp_list *rlist, unsigned int state) { unsigned int x; - rlist->rl_ghs = kcalloc(rlist->rl_rgrps, sizeof(struct gfs2_holder), + rlist->rl_ghs = kmalloc(rlist->rl_rgrps * sizeof(struct gfs2_holder), GFP_NOFS | __GFP_NOFAIL); for (x = 0; x < rlist->rl_rgrps; x++) gfs2_holder_init(rlist->rl_rgd[x]->rd_gl, diff --git a/fs/gfs2/super.c b/fs/gfs2/super.c index 9b2ff353e45f..3a7e60bb39f8 100644 --- a/fs/gfs2/super.c +++ b/fs/gfs2/super.c @@ -855,7 +855,7 @@ static int gfs2_make_fs_ro(struct gfs2_sbd *sdp) wait_event(sdp->sd_reserving_log_wait, atomic_read(&sdp->sd_reserving_log) == 0); gfs2_assert_warn(sdp, atomic_read(&sdp->sd_log_blks_free) == sdp->sd_jdesc->jd_blocks); - if (freeze_gh.gh_gl) + if (gfs2_holder_initialized(&freeze_gh)) gfs2_glock_dq_uninit(&freeze_gh); gfs2_quota_cleanup(sdp); @@ -1033,7 +1033,7 @@ static int gfs2_unfreeze(struct super_block *sb) mutex_lock(&sdp->sd_freeze_mutex); if (atomic_read(&sdp->sd_freeze_state) != SFS_FROZEN || - sdp->sd_freeze_gh.gh_gl == NULL) { + !gfs2_holder_initialized(&sdp->sd_freeze_gh)) { mutex_unlock(&sdp->sd_freeze_mutex); return 0; } @@ -1084,9 +1084,11 @@ static int gfs2_statfs_slow(struct gfs2_sbd *sdp, struct gfs2_statfs_change_host int error = 0, err; memset(sc, 0, sizeof(struct gfs2_statfs_change_host)); - gha = kcalloc(slots, sizeof(struct gfs2_holder), GFP_KERNEL); + gha = kmalloc(slots * sizeof(struct gfs2_holder), GFP_KERNEL); if (!gha) return -ENOMEM; + for (x = 0; x < slots; x++) + gfs2_holder_mark_uninitialized(gha + x); rgd_next = gfs2_rgrpd_get_first(sdp); @@ -1096,7 +1098,7 @@ static int gfs2_statfs_slow(struct gfs2_sbd *sdp, struct gfs2_statfs_change_host for (x = 0; x < slots; x++) { gh = gha + x; - if (gh->gh_gl && gfs2_glock_poll(gh)) { + if (gfs2_holder_initialized(gh) && gfs2_glock_poll(gh)) { err = gfs2_glock_wait(gh); if (err) { gfs2_holder_uninit(gh); @@ -1109,7 +1111,7 @@ static int gfs2_statfs_slow(struct gfs2_sbd *sdp, struct gfs2_statfs_change_host } } - if (gh->gh_gl) + if (gfs2_holder_initialized(gh)) done = 0; else if (rgd_next && !error) { error = gfs2_glock_nq_init(rgd_next->rd_gl, @@ -1304,9 +1306,11 @@ static int gfs2_drop_inode(struct inode *inode) { struct gfs2_inode *ip = GFS2_I(inode); - if (!test_bit(GIF_FREE_VFS_INODE, &ip->i_flags) && inode->i_nlink) { + if (!test_bit(GIF_FREE_VFS_INODE, &ip->i_flags) && + inode->i_nlink && + gfs2_holder_initialized(&ip->i_iopen_gh)) { struct gfs2_glock *gl = ip->i_iopen_gh.gh_gl; - if (gl && test_bit(GLF_DEMOTE, &gl->gl_flags)) + if (test_bit(GLF_DEMOTE, &gl->gl_flags)) clear_nlink(inode); } return generic_drop_inode(inode); @@ -1551,7 +1555,7 @@ static void gfs2_evict_inode(struct inode *inode) goto out_truncate; } - if (ip->i_iopen_gh.gh_gl && + if (gfs2_holder_initialized(&ip->i_iopen_gh) && test_bit(HIF_HOLDER, &ip->i_iopen_gh.gh_iflags)) { ip->i_iopen_gh.gh_flags |= GL_NOCACHE; gfs2_glock_dq_wait(&ip->i_iopen_gh); @@ -1610,7 +1614,7 @@ static void gfs2_evict_inode(struct inode *inode) if (gfs2_rs_active(&ip->i_res)) gfs2_rs_deltree(&ip->i_res); - if (ip->i_iopen_gh.gh_gl) { + if (gfs2_holder_initialized(&ip->i_iopen_gh)) { if (test_bit(HIF_HOLDER, &ip->i_iopen_gh.gh_iflags)) { ip->i_iopen_gh.gh_flags |= GL_NOCACHE; gfs2_glock_dq_wait(&ip->i_iopen_gh); @@ -1632,7 +1636,7 @@ static void gfs2_evict_inode(struct inode *inode) gfs2_glock_add_to_lru(ip->i_gl); gfs2_glock_put(ip->i_gl); ip->i_gl = NULL; - if (ip->i_iopen_gh.gh_gl) { + if (gfs2_holder_initialized(&ip->i_iopen_gh)) { ip->i_iopen_gh.gh_gl->gl_object = NULL; ip->i_iopen_gh.gh_flags |= GL_NOCACHE; gfs2_glock_dq_wait(&ip->i_iopen_gh);