diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2022-10-10 20:13:22 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2022-10-10 20:13:22 -0700 |
commit | 288fc86067620dcbec34a335b95b75635551e8fe (patch) | |
tree | 9d18c8bbee7078b1f2ec44d457f49aeb7325603c | |
parent | 4875d2ffb0104db625db281944d18e8987f97030 (diff) | |
parent | c7d7d2d345697eb3781198e58a22504feb74af63 (diff) |
Merge tag 'gfs2-nopid-for-v6.1' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2
Pull gfs2 debugfs updates from Andreas Gruenbacher:
- Improve the way how the state of glocks is reported in debugfs for
glocks which are not held by processes, but rather by other resouces
like cached inodes or flocks.
* tag 'gfs2-nopid-for-v6.1' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2:
gfs2: Mark the remaining process-independent glock holders as GL_NOPID
gfs2: Mark flock glock holders as GL_NOPID
gfs2: Add GL_NOPID flag for process-independent glock holders
gfs2: Add flocks to glockfd debugfs file
gfs2: Add glockfd debugfs file
-rw-r--r-- | fs/file.c | 1 | ||||
-rw-r--r-- | fs/gfs2/file.c | 29 | ||||
-rw-r--r-- | fs/gfs2/glock.c | 213 | ||||
-rw-r--r-- | fs/gfs2/glock.h | 1 | ||||
-rw-r--r-- | fs/gfs2/inode.c | 5 | ||||
-rw-r--r-- | fs/gfs2/ops_fstype.c | 14 | ||||
-rw-r--r-- | fs/gfs2/super.c | 3 | ||||
-rw-r--r-- | fs/gfs2/util.c | 6 | ||||
-rw-r--r-- | kernel/pid.c | 1 |
9 files changed, 248 insertions, 25 deletions
diff --git a/fs/file.c b/fs/file.c index 3bcc1ecc314a..5f9c802a5d8d 100644 --- a/fs/file.c +++ b/fs/file.c @@ -980,6 +980,7 @@ struct file *task_lookup_next_fd_rcu(struct task_struct *task, unsigned int *ret *ret_fd = fd; return file; } +EXPORT_SYMBOL(task_lookup_next_fd_rcu); /* * Lightweight file lookup - no refcnt increment if fd table isn't shared. diff --git a/fs/gfs2/file.c b/fs/gfs2/file.c index 892006fbbb09..60c6fb91fb58 100644 --- a/fs/gfs2/file.c +++ b/fs/gfs2/file.c @@ -1443,6 +1443,22 @@ static int gfs2_lock(struct file *file, int cmd, struct file_lock *fl) return dlm_posix_lock(ls->ls_dlm, ip->i_no_addr, file, cmd, fl); } +static void __flock_holder_uninit(struct file *file, struct gfs2_holder *fl_gh) +{ + struct gfs2_glock *gl = fl_gh->gh_gl; + + /* + * Make sure gfs2_glock_put() won't sleep under the file->f_lock + * spinlock. + */ + + gfs2_glock_hold(gl); + spin_lock(&file->f_lock); + gfs2_holder_uninit(fl_gh); + spin_unlock(&file->f_lock); + gfs2_glock_put(gl); +} + static int do_flock(struct file *file, int cmd, struct file_lock *fl) { struct gfs2_file *fp = file->private_data; @@ -1455,7 +1471,9 @@ static int do_flock(struct file *file, int cmd, struct file_lock *fl) int sleeptime; state = (fl->fl_type == F_WRLCK) ? LM_ST_EXCLUSIVE : LM_ST_SHARED; - flags = (IS_SETLKW(cmd) ? 0 : LM_FLAG_TRY_1CB) | GL_EXACT; + flags = GL_EXACT | GL_NOPID; + if (!IS_SETLKW(cmd)) + flags |= LM_FLAG_TRY_1CB; mutex_lock(&fp->f_fl_mutex); @@ -1474,18 +1492,21 @@ static int do_flock(struct file *file, int cmd, struct file_lock *fl) &gfs2_flock_glops, CREATE, &gl); if (error) goto out; + spin_lock(&file->f_lock); gfs2_holder_init(gl, state, flags, fl_gh); + spin_unlock(&file->f_lock); gfs2_glock_put(gl); } for (sleeptime = 1; sleeptime <= 4; sleeptime <<= 1) { error = gfs2_glock_nq(fl_gh); if (error != GLR_TRYFAILED) break; - fl_gh->gh_flags = LM_FLAG_TRY | GL_EXACT; + fl_gh->gh_flags &= ~LM_FLAG_TRY_1CB; + fl_gh->gh_flags |= LM_FLAG_TRY; msleep(sleeptime); } if (error) { - gfs2_holder_uninit(fl_gh); + __flock_holder_uninit(file, fl_gh); if (error == GLR_TRYFAILED) error = -EAGAIN; } else { @@ -1507,7 +1528,7 @@ static void do_unflock(struct file *file, struct file_lock *fl) locks_lock_file_wait(file, fl); if (gfs2_holder_initialized(fl_gh)) { gfs2_glock_dq(fl_gh); - gfs2_holder_uninit(fl_gh); + __flock_holder_uninit(file, fl_gh); } mutex_unlock(&fp->f_fl_mutex); } diff --git a/fs/gfs2/glock.c b/fs/gfs2/glock.c index dca2cbf0338c..df335c258eb0 100644 --- a/fs/gfs2/glock.c +++ b/fs/gfs2/glock.c @@ -33,6 +33,9 @@ #include <linux/list_sort.h> #include <linux/lockref.h> #include <linux/rhashtable.h> +#include <linux/pid_namespace.h> +#include <linux/fdtable.h> +#include <linux/file.h> #include "gfs2.h" #include "incore.h" @@ -1456,6 +1459,15 @@ void gfs2_print_dbg(struct seq_file *seq, const char *fmt, ...) va_end(args); } +static inline bool pid_is_meaningful(const struct gfs2_holder *gh) +{ + if (!(gh->gh_flags & GL_NOPID)) + return true; + if (gh->gh_state == LM_ST_UNLOCKED) + return true; + return false; +} + /** * add_to_queue - Add a holder to the wait queue (but look for recursion) * @gh: the holder structure to add @@ -1492,10 +1504,17 @@ __acquires(&gl->gl_lockref.lock) } list_for_each_entry(gh2, &gl->gl_holders, gh_list) { - if (unlikely(gh2->gh_owner_pid == gh->gh_owner_pid && - (gh->gh_gl->gl_ops->go_type != LM_TYPE_FLOCK) && - !test_bit(HIF_MAY_DEMOTE, &gh2->gh_iflags))) - goto trap_recursive; + if (likely(gh2->gh_owner_pid != gh->gh_owner_pid)) + continue; + if (gh->gh_gl->gl_ops->go_type == LM_TYPE_FLOCK) + continue; + if (test_bit(HIF_MAY_DEMOTE, &gh2->gh_iflags)) + continue; + if (!pid_is_meaningful(gh2)) + continue; + goto trap_recursive; + } + list_for_each_entry(gh2, &gl->gl_holders, gh_list) { if (try_futile && !(gh2->gh_flags & (LM_FLAG_TRY | LM_FLAG_TRY_1CB))) { fail: @@ -2306,19 +2325,24 @@ static const char *hflags2str(char *buf, u16 flags, unsigned long iflags) static void dump_holder(struct seq_file *seq, const struct gfs2_holder *gh, const char *fs_id_buf) { - struct task_struct *gh_owner = NULL; + const char *comm = "(none)"; + pid_t owner_pid = 0; char flags_buf[32]; rcu_read_lock(); - if (gh->gh_owner_pid) + if (pid_is_meaningful(gh)) { + struct task_struct *gh_owner; + + comm = "(ended)"; + owner_pid = pid_nr(gh->gh_owner_pid); gh_owner = pid_task(gh->gh_owner_pid, PIDTYPE_PID); + if (gh_owner) + comm = gh_owner->comm; + } gfs2_print_dbg(seq, "%s H: s:%s f:%s e:%d p:%ld [%s] %pS\n", fs_id_buf, state2str(gh->gh_state), hflags2str(flags_buf, gh->gh_flags, gh->gh_iflags), - gh->gh_error, - gh->gh_owner_pid ? (long)pid_nr(gh->gh_owner_pid) : -1, - gh_owner ? gh_owner->comm : "(ended)", - (void *)gh->gh_ip); + gh->gh_error, (long)owner_pid, comm, (void *)gh->gh_ip); rcu_read_unlock(); } @@ -2733,6 +2757,172 @@ static const struct file_operations gfs2_glstats_fops = { .release = gfs2_glocks_release, }; +struct gfs2_glockfd_iter { + struct super_block *sb; + unsigned int tgid; + struct task_struct *task; + unsigned int fd; + struct file *file; +}; + +static struct task_struct *gfs2_glockfd_next_task(struct gfs2_glockfd_iter *i) +{ + struct pid_namespace *ns = task_active_pid_ns(current); + struct pid *pid; + + if (i->task) + put_task_struct(i->task); + + rcu_read_lock(); +retry: + i->task = NULL; + pid = find_ge_pid(i->tgid, ns); + if (pid) { + i->tgid = pid_nr_ns(pid, ns); + i->task = pid_task(pid, PIDTYPE_TGID); + if (!i->task) { + i->tgid++; + goto retry; + } + get_task_struct(i->task); + } + rcu_read_unlock(); + return i->task; +} + +static struct file *gfs2_glockfd_next_file(struct gfs2_glockfd_iter *i) +{ + if (i->file) { + fput(i->file); + i->file = NULL; + } + + rcu_read_lock(); + for(;; i->fd++) { + struct inode *inode; + + i->file = task_lookup_next_fd_rcu(i->task, &i->fd); + if (!i->file) { + i->fd = 0; + break; + } + inode = file_inode(i->file); + if (inode->i_sb != i->sb) + continue; + if (get_file_rcu(i->file)) + break; + } + rcu_read_unlock(); + return i->file; +} + +static void *gfs2_glockfd_seq_start(struct seq_file *seq, loff_t *pos) +{ + struct gfs2_glockfd_iter *i = seq->private; + + if (*pos) + return NULL; + while (gfs2_glockfd_next_task(i)) { + if (gfs2_glockfd_next_file(i)) + return i; + i->tgid++; + } + return NULL; +} + +static void *gfs2_glockfd_seq_next(struct seq_file *seq, void *iter_ptr, + loff_t *pos) +{ + struct gfs2_glockfd_iter *i = seq->private; + + (*pos)++; + i->fd++; + do { + if (gfs2_glockfd_next_file(i)) + return i; + i->tgid++; + } while (gfs2_glockfd_next_task(i)); + return NULL; +} + +static void gfs2_glockfd_seq_stop(struct seq_file *seq, void *iter_ptr) +{ + struct gfs2_glockfd_iter *i = seq->private; + + if (i->file) + fput(i->file); + if (i->task) + put_task_struct(i->task); +} + +static void gfs2_glockfd_seq_show_flock(struct seq_file *seq, + struct gfs2_glockfd_iter *i) +{ + struct gfs2_file *fp = i->file->private_data; + struct gfs2_holder *fl_gh = &fp->f_fl_gh; + struct lm_lockname gl_name = { .ln_type = LM_TYPE_RESERVED }; + + if (!READ_ONCE(fl_gh->gh_gl)) + return; + + spin_lock(&i->file->f_lock); + if (gfs2_holder_initialized(fl_gh)) + gl_name = fl_gh->gh_gl->gl_name; + spin_unlock(&i->file->f_lock); + + if (gl_name.ln_type != LM_TYPE_RESERVED) { + seq_printf(seq, "%d %u %u/%llx\n", + i->tgid, i->fd, gl_name.ln_type, + (unsigned long long)gl_name.ln_number); + } +} + +static int gfs2_glockfd_seq_show(struct seq_file *seq, void *iter_ptr) +{ + struct gfs2_glockfd_iter *i = seq->private; + struct inode *inode = file_inode(i->file); + struct gfs2_glock *gl; + + inode_lock_shared(inode); + gl = GFS2_I(inode)->i_iopen_gh.gh_gl; + if (gl) { + seq_printf(seq, "%d %u %u/%llx\n", + i->tgid, i->fd, gl->gl_name.ln_type, + (unsigned long long)gl->gl_name.ln_number); + } + gfs2_glockfd_seq_show_flock(seq, i); + inode_unlock_shared(inode); + return 0; +} + +static const struct seq_operations gfs2_glockfd_seq_ops = { + .start = gfs2_glockfd_seq_start, + .next = gfs2_glockfd_seq_next, + .stop = gfs2_glockfd_seq_stop, + .show = gfs2_glockfd_seq_show, +}; + +static int gfs2_glockfd_open(struct inode *inode, struct file *file) +{ + struct gfs2_glockfd_iter *i; + struct gfs2_sbd *sdp = inode->i_private; + + i = __seq_open_private(file, &gfs2_glockfd_seq_ops, + sizeof(struct gfs2_glockfd_iter)); + if (!i) + return -ENOMEM; + i->sb = sdp->sd_vfs; + return 0; +} + +static const struct file_operations gfs2_glockfd_fops = { + .owner = THIS_MODULE, + .open = gfs2_glockfd_open, + .read = seq_read, + .llseek = seq_lseek, + .release = seq_release_private, +}; + DEFINE_SEQ_ATTRIBUTE(gfs2_sbstats); void gfs2_create_debugfs_file(struct gfs2_sbd *sdp) @@ -2742,6 +2932,9 @@ void gfs2_create_debugfs_file(struct gfs2_sbd *sdp) debugfs_create_file("glocks", S_IFREG | S_IRUGO, sdp->debugfs_dir, sdp, &gfs2_glocks_fops); + debugfs_create_file("glockfd", S_IFREG | S_IRUGO, sdp->debugfs_dir, sdp, + &gfs2_glockfd_fops); + debugfs_create_file("glstats", S_IFREG | S_IRUGO, sdp->debugfs_dir, sdp, &gfs2_glstats_fops); diff --git a/fs/gfs2/glock.h b/fs/gfs2/glock.h index 0199a3dcb114..0d068f4fd7d6 100644 --- a/fs/gfs2/glock.h +++ b/fs/gfs2/glock.h @@ -91,6 +91,7 @@ enum { #define GL_ASYNC 0x0040 #define GL_EXACT 0x0080 #define GL_SKIP 0x0100 +#define GL_NOPID 0x0200 #define GL_NOCACHE 0x0400 /* diff --git a/fs/gfs2/inode.c b/fs/gfs2/inode.c index 56ded979988c..04a201584fa7 100644 --- a/fs/gfs2/inode.c +++ b/fs/gfs2/inode.c @@ -147,7 +147,7 @@ struct inode *gfs2_inode_lookup(struct super_block *sb, unsigned int type, else gfs2_cancel_delete_work(io_gl); error = gfs2_glock_nq_init(io_gl, LM_ST_SHARED, - GL_EXACT | extra_flags, + GL_EXACT | GL_NOPID | extra_flags, &ip->i_iopen_gh); gfs2_glock_put(io_gl); if (unlikely(error)) @@ -726,7 +726,8 @@ static int gfs2_create_inode(struct inode *dir, struct dentry *dentry, error = insert_inode_locked4(inode, ip->i_no_addr, iget_test, &ip->i_no_addr); BUG_ON(error); - error = gfs2_glock_nq_init(io_gl, LM_ST_SHARED, GL_EXACT, &ip->i_iopen_gh); + error = gfs2_glock_nq_init(io_gl, LM_ST_SHARED, GL_EXACT | GL_NOPID, + &ip->i_iopen_gh); if (error) goto fail_gunlock2; diff --git a/fs/gfs2/ops_fstype.c b/fs/gfs2/ops_fstype.c index c7e2e6238366..c0cf1d2d0ef5 100644 --- a/fs/gfs2/ops_fstype.c +++ b/fs/gfs2/ops_fstype.c @@ -406,7 +406,8 @@ static int init_locking(struct gfs2_sbd *sdp, struct gfs2_holder *mount_gh, error = gfs2_glock_nq_num(sdp, GFS2_MOUNT_LOCK, &gfs2_nondisk_glops, - LM_ST_EXCLUSIVE, LM_FLAG_NOEXP | GL_NOCACHE, + LM_ST_EXCLUSIVE, + LM_FLAG_NOEXP | GL_NOCACHE | GL_NOPID, mount_gh); if (error) { fs_err(sdp, "can't acquire mount glock: %d\n", error); @@ -416,7 +417,7 @@ static int init_locking(struct gfs2_sbd *sdp, struct gfs2_holder *mount_gh, error = gfs2_glock_nq_num(sdp, GFS2_LIVE_LOCK, &gfs2_nondisk_glops, LM_ST_SHARED, - LM_FLAG_NOEXP | GL_EXACT, + LM_FLAG_NOEXP | GL_EXACT | GL_NOPID, &sdp->sd_live_gh); if (error) { fs_err(sdp, "can't acquire live glock: %d\n", error); @@ -692,7 +693,7 @@ static int init_statfs(struct gfs2_sbd *sdp) iput(pn); pn = NULL; ip = GFS2_I(sdp->sd_sc_inode); - error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, + error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, GL_NOPID, &sdp->sd_sc_gh); if (error) { fs_err(sdp, "can't lock local \"sc\" file: %d\n", error); @@ -781,7 +782,7 @@ static int init_journal(struct gfs2_sbd *sdp, int undo) error = gfs2_glock_nq_num(sdp, sdp->sd_lockstruct.ls_jid, &gfs2_journal_glops, LM_ST_EXCLUSIVE, - LM_FLAG_NOEXP | GL_NOCACHE, + LM_FLAG_NOEXP | GL_NOCACHE | GL_NOPID, &sdp->sd_journal_gh); if (error) { fs_err(sdp, "can't acquire journal glock: %d\n", error); @@ -791,7 +792,8 @@ static int init_journal(struct gfs2_sbd *sdp, int undo) ip = GFS2_I(sdp->sd_jdesc->jd_inode); sdp->sd_jinode_gl = ip->i_gl; error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, - LM_FLAG_NOEXP | GL_EXACT | GL_NOCACHE, + LM_FLAG_NOEXP | GL_EXACT | + GL_NOCACHE | GL_NOPID, &sdp->sd_jinode_gh); if (error) { fs_err(sdp, "can't acquire journal inode glock: %d\n", @@ -962,7 +964,7 @@ static int init_per_node(struct gfs2_sbd *sdp, int undo) pn = NULL; ip = GFS2_I(sdp->sd_qc_inode); - error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, + error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, GL_NOPID, &sdp->sd_qc_gh); if (error) { fs_err(sdp, "can't lock local \"qc\" file: %d\n", error); diff --git a/fs/gfs2/super.c b/fs/gfs2/super.c index b5b0f285b27f..b018957a1bb2 100644 --- a/fs/gfs2/super.c +++ b/fs/gfs2/super.c @@ -346,7 +346,8 @@ static int gfs2_lock_fs_check_clean(struct gfs2_sbd *sdp) } error = gfs2_glock_nq_init(sdp->sd_freeze_gl, LM_ST_EXCLUSIVE, - LM_FLAG_NOEXP, &sdp->sd_freeze_gh); + LM_FLAG_NOEXP | GL_NOPID, + &sdp->sd_freeze_gh); if (error) goto out; diff --git a/fs/gfs2/util.c b/fs/gfs2/util.c index 88185a341504..7a6aeffcdf5c 100644 --- a/fs/gfs2/util.c +++ b/fs/gfs2/util.c @@ -232,7 +232,8 @@ static void signal_our_withdraw(struct gfs2_sbd *sdp) */ fs_warn(sdp, "Requesting recovery of jid %d.\n", sdp->sd_lockstruct.ls_jid); - gfs2_holder_reinit(LM_ST_EXCLUSIVE, LM_FLAG_TRY_1CB | LM_FLAG_NOEXP, + gfs2_holder_reinit(LM_ST_EXCLUSIVE, + LM_FLAG_TRY_1CB | LM_FLAG_NOEXP | GL_NOPID, &sdp->sd_live_gh); msleep(GL_GLOCK_MAX_HOLD); /* @@ -257,7 +258,8 @@ static void signal_our_withdraw(struct gfs2_sbd *sdp) fs_warn(sdp, "Unable to recover our journal jid %d.\n", sdp->sd_lockstruct.ls_jid); gfs2_glock_dq_wait(&sdp->sd_live_gh); - gfs2_holder_reinit(LM_ST_SHARED, LM_FLAG_NOEXP | GL_EXACT, + gfs2_holder_reinit(LM_ST_SHARED, + LM_FLAG_NOEXP | GL_EXACT | GL_NOPID, &sdp->sd_live_gh); gfs2_glock_nq(&sdp->sd_live_gh); } diff --git a/kernel/pid.c b/kernel/pid.c index 2fc0a16ec77b..3fbc5e46b721 100644 --- a/kernel/pid.c +++ b/kernel/pid.c @@ -519,6 +519,7 @@ struct pid *find_ge_pid(int nr, struct pid_namespace *ns) { return idr_get_next(&ns->idr, &nr); } +EXPORT_SYMBOL_GPL(find_ge_pid); struct pid *pidfd_get_pid(unsigned int fd, unsigned int *flags) { |