diff options
author | Luo Longjun <luolongjun@huawei.com> | 2021-02-26 04:58:29 +0100 |
---|---|---|
committer | Jeff Layton <jlayton@kernel.org> | 2021-03-11 13:48:11 +0100 |
commit | b8da9b10e26cee58eba7b0fd72717127edfb316b (patch) | |
tree | 1387b885216317522fb97fa47d30d96fd9eb1700 /fs/locks.c | |
parent | Linux 5.12-rc2 (diff) | |
download | linux-b8da9b10e26cee58eba7b0fd72717127edfb316b.tar.xz linux-b8da9b10e26cee58eba7b0fd72717127edfb316b.zip |
fs/locks: print full locks information
Commit fd7732e033e3 ("fs/locks: create a tree of dependent requests.")
has put blocked locks into a tree.
So, with a for loop, we can't check all locks information.
To solve this problem, we should traverse the tree.
Signed-off-by: Luo Longjun <luolongjun@huawei.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Diffstat (limited to 'fs/locks.c')
-rw-r--r-- | fs/locks.c | 65 |
1 files changed, 56 insertions, 9 deletions
diff --git a/fs/locks.c b/fs/locks.c index 99ca97e81b7a..ecaecd1f1b58 100644 --- a/fs/locks.c +++ b/fs/locks.c @@ -2828,7 +2828,7 @@ struct locks_iterator { }; static void lock_get_status(struct seq_file *f, struct file_lock *fl, - loff_t id, char *pfx) + loff_t id, char *pfx, int repeat) { struct inode *inode = NULL; unsigned int fl_pid; @@ -2844,7 +2844,11 @@ static void lock_get_status(struct seq_file *f, struct file_lock *fl, if (fl->fl_file != NULL) inode = locks_inode(fl->fl_file); - seq_printf(f, "%lld:%s ", id, pfx); + seq_printf(f, "%lld: ", id); + + if (repeat) + seq_printf(f, "%*s", repeat - 1 + (int)strlen(pfx), pfx); + if (IS_POSIX(fl)) { if (fl->fl_flags & FL_ACCESS) seq_puts(f, "ACCESS"); @@ -2906,21 +2910,64 @@ static void lock_get_status(struct seq_file *f, struct file_lock *fl, } } +static struct file_lock *get_next_blocked_member(struct file_lock *node) +{ + struct file_lock *tmp; + + /* NULL node or root node */ + if (node == NULL || node->fl_blocker == NULL) + return NULL; + + /* Next member in the linked list could be itself */ + tmp = list_next_entry(node, fl_blocked_member); + if (list_entry_is_head(tmp, &node->fl_blocker->fl_blocked_requests, fl_blocked_member) + || tmp == node) { + return NULL; + } + + return tmp; +} + static int locks_show(struct seq_file *f, void *v) { struct locks_iterator *iter = f->private; - struct file_lock *fl, *bfl; + struct file_lock *cur, *tmp; struct pid_namespace *proc_pidns = proc_pid_ns(file_inode(f->file)->i_sb); + int level = 0; - fl = hlist_entry(v, struct file_lock, fl_link); + cur = hlist_entry(v, struct file_lock, fl_link); - if (locks_translate_pid(fl, proc_pidns) == 0) + if (locks_translate_pid(cur, proc_pidns) == 0) return 0; - lock_get_status(f, fl, iter->li_pos, ""); + /* View this crossed linked list as a binary tree, the first member of fl_blocked_requests + * is the left child of current node, the next silibing in fl_blocked_member is the + * right child, we can alse get the parent of current node from fl_blocker, so this + * question becomes traversal of a binary tree + */ + while (cur != NULL) { + if (level) + lock_get_status(f, cur, iter->li_pos, "-> ", level); + else + lock_get_status(f, cur, iter->li_pos, "", level); - list_for_each_entry(bfl, &fl->fl_blocked_requests, fl_blocked_member) - lock_get_status(f, bfl, iter->li_pos, " ->"); + if (!list_empty(&cur->fl_blocked_requests)) { + /* Turn left */ + cur = list_first_entry_or_null(&cur->fl_blocked_requests, + struct file_lock, fl_blocked_member); + level++; + } else { + /* Turn right */ + tmp = get_next_blocked_member(cur); + /* Fall back to parent node */ + while (tmp == NULL && cur->fl_blocker != NULL) { + cur = cur->fl_blocker; + level--; + tmp = get_next_blocked_member(cur); + } + cur = tmp; + } + } return 0; } @@ -2941,7 +2988,7 @@ static void __show_fd_locks(struct seq_file *f, (*id)++; seq_puts(f, "lock:\t"); - lock_get_status(f, fl, *id, ""); + lock_get_status(f, fl, *id, "", 0); } } |