From 4e3d24ed1a1285fe3289653aacc965642706bacb Mon Sep 17 00:00:00 2001 From: Sunil Mushran Date: Mon, 10 Mar 2008 15:16:24 -0700 Subject: [PATCH] ocfs2/dlm: Dumps the lockres' into a debugfs file This patch dumps all the lockres' alongwith all the locks into a debugfs file. Useful for debugging. Signed-off-by: Sunil Mushran Signed-off-by: Joel Becker Signed-off-by: Mark Fasheh --- fs/ocfs2/dlm/dlmdebug.c | 247 ++++++++++++++++++++++++++++++++++++++++ fs/ocfs2/dlm/dlmdebug.h | 8 ++ 2 files changed, 255 insertions(+) diff --git a/fs/ocfs2/dlm/dlmdebug.c b/fs/ocfs2/dlm/dlmdebug.c index e33540380013..cccb1ce33723 100644 --- a/fs/ocfs2/dlm/dlmdebug.c +++ b/fs/ocfs2/dlm/dlmdebug.c @@ -273,8 +273,35 @@ EXPORT_SYMBOL_GPL(dlm_errname); static struct dentry *dlm_debugfs_root = NULL; +/* NOTE: This function converts a lockname into a string. It uses knowledge + * of the format of the lockname that should be outside the purview of the dlm. + * We are adding only to make dlm debugging slightly easier. + * + * For more on lockname formats, please refer to dlmglue.c and ocfs2_lockid.h. + */ +static int stringify_lockname(const char *lockname, int locklen, + char *buf, int len) +{ + int out = 0; + __be64 inode_blkno_be; + +#define OCFS2_DENTRY_LOCK_INO_START 18 + if (*lockname == 'N') { + memcpy((__be64 *)&inode_blkno_be, + (char *)&lockname[OCFS2_DENTRY_LOCK_INO_START], + sizeof(__be64)); + out += snprintf(buf + out, len - out, "%.*s%08x", + OCFS2_DENTRY_LOCK_INO_START - 1, lockname, + (unsigned int)be64_to_cpu(inode_blkno_be)); + } else + out += snprintf(buf + out, len - out, "%.*s", + locklen, lockname); + return out; +} + #define DLM_DEBUGFS_DIR "o2dlm" #define DLM_DEBUGFS_DLM_STATE "dlm_state" +#define DLM_DEBUGFS_LOCKING_STATE "locking_state" /* begin - utils funcs */ static void dlm_debug_free(struct kref *kref) @@ -368,6 +395,213 @@ static int debug_buffer_release(struct inode *inode, struct file *file) } /* end - util funcs */ +/* begin - debug lockres funcs */ +static int dump_lock(struct dlm_lock *lock, int list_type, char *buf, int len) +{ + int out; + +#define DEBUG_LOCK_VERSION 1 + spin_lock(&lock->spinlock); + out = snprintf(buf, len, "LOCK:%d,%d,%d,%d,%d,%d:%lld,%d,%d,%d,%d,%d," + "%d,%d,%d,%d\n", + DEBUG_LOCK_VERSION, + list_type, lock->ml.type, lock->ml.convert_type, + lock->ml.node, + dlm_get_lock_cookie_node(be64_to_cpu(lock->ml.cookie)), + dlm_get_lock_cookie_seq(be64_to_cpu(lock->ml.cookie)), + !list_empty(&lock->ast_list), + !list_empty(&lock->bast_list), + lock->ast_pending, lock->bast_pending, + lock->convert_pending, lock->lock_pending, + lock->cancel_pending, lock->unlock_pending, + atomic_read(&lock->lock_refs.refcount)); + spin_unlock(&lock->spinlock); + + return out; +} + +static int dump_lockres(struct dlm_lock_resource *res, char *buf, int len) +{ + struct dlm_lock *lock; + int i; + int out = 0; + + out += snprintf(buf + out, len - out, "NAME:"); + out += stringify_lockname(res->lockname.name, res->lockname.len, + buf + out, len - out); + out += snprintf(buf + out, len - out, "\n"); + +#define DEBUG_LRES_VERSION 1 + out += snprintf(buf + out, len - out, + "LRES:%d,%d,%d,%ld,%d,%d,%d,%d,%d,%d,%d\n", + DEBUG_LRES_VERSION, + res->owner, res->state, res->last_used, + !list_empty(&res->purge), + !list_empty(&res->dirty), + !list_empty(&res->recovering), + res->inflight_locks, res->migration_pending, + atomic_read(&res->asts_reserved), + atomic_read(&res->refs.refcount)); + + /* refmap */ + out += snprintf(buf + out, len - out, "RMAP:"); + out += stringify_nodemap(res->refmap, O2NM_MAX_NODES, + buf + out, len - out); + out += snprintf(buf + out, len - out, "\n"); + + /* lvb */ + out += snprintf(buf + out, len - out, "LVBX:"); + for (i = 0; i < DLM_LVB_LEN; i++) + out += snprintf(buf + out, len - out, + "%02x", (unsigned char)res->lvb[i]); + out += snprintf(buf + out, len - out, "\n"); + + /* granted */ + list_for_each_entry(lock, &res->granted, list) + out += dump_lock(lock, 0, buf + out, len - out); + + /* converting */ + list_for_each_entry(lock, &res->converting, list) + out += dump_lock(lock, 1, buf + out, len - out); + + /* blocked */ + list_for_each_entry(lock, &res->blocked, list) + out += dump_lock(lock, 2, buf + out, len - out); + + out += snprintf(buf + out, len - out, "\n"); + + return out; +} + +static void *lockres_seq_start(struct seq_file *m, loff_t *pos) +{ + struct debug_lockres *dl = m->private; + struct dlm_ctxt *dlm = dl->dl_ctxt; + struct dlm_lock_resource *res = NULL; + + spin_lock(&dlm->spinlock); + + if (dl->dl_res) { + list_for_each_entry(res, &dl->dl_res->tracking, tracking) { + if (dl->dl_res) { + dlm_lockres_put(dl->dl_res); + dl->dl_res = NULL; + } + if (&res->tracking == &dlm->tracking_list) { + mlog(0, "End of list found, %p\n", res); + dl = NULL; + break; + } + dlm_lockres_get(res); + dl->dl_res = res; + break; + } + } else { + if (!list_empty(&dlm->tracking_list)) { + list_for_each_entry(res, &dlm->tracking_list, tracking) + break; + dlm_lockres_get(res); + dl->dl_res = res; + } else + dl = NULL; + } + + if (dl) { + spin_lock(&dl->dl_res->spinlock); + dump_lockres(dl->dl_res, dl->dl_buf, dl->dl_len - 1); + spin_unlock(&dl->dl_res->spinlock); + } + + spin_unlock(&dlm->spinlock); + + return dl; +} + +static void lockres_seq_stop(struct seq_file *m, void *v) +{ +} + +static void *lockres_seq_next(struct seq_file *m, void *v, loff_t *pos) +{ + return NULL; +} + +static int lockres_seq_show(struct seq_file *s, void *v) +{ + struct debug_lockres *dl = (struct debug_lockres *)v; + + seq_printf(s, "%s", dl->dl_buf); + + return 0; +} + +static struct seq_operations debug_lockres_ops = { + .start = lockres_seq_start, + .stop = lockres_seq_stop, + .next = lockres_seq_next, + .show = lockres_seq_show, +}; + +static int debug_lockres_open(struct inode *inode, struct file *file) +{ + struct dlm_ctxt *dlm = inode->i_private; + int ret = -ENOMEM; + struct seq_file *seq; + struct debug_lockres *dl = NULL; + + dl = kzalloc(sizeof(struct debug_lockres), GFP_KERNEL); + if (!dl) { + mlog_errno(ret); + goto bail; + } + + dl->dl_len = PAGE_SIZE; + dl->dl_buf = kmalloc(dl->dl_len, GFP_KERNEL); + if (!dl->dl_buf) { + mlog_errno(ret); + goto bail; + } + + ret = seq_open(file, &debug_lockres_ops); + if (ret) { + mlog_errno(ret); + goto bail; + } + + seq = (struct seq_file *) file->private_data; + seq->private = dl; + + dlm_grab(dlm); + dl->dl_ctxt = dlm; + + return 0; +bail: + if (dl) + kfree(dl->dl_buf); + kfree(dl); + return ret; +} + +static int debug_lockres_release(struct inode *inode, struct file *file) +{ + struct seq_file *seq = (struct seq_file *)file->private_data; + struct debug_lockres *dl = (struct debug_lockres *)seq->private; + + if (dl->dl_res) + dlm_lockres_put(dl->dl_res); + dlm_put(dl->dl_ctxt); + kfree(dl->dl_buf); + return seq_release_private(inode, file); +} + +static struct file_operations debug_lockres_fops = { + .open = debug_lockres_open, + .release = debug_lockres_release, + .read = seq_read, + .llseek = seq_lseek, +}; +/* end - debug lockres funcs */ + /* begin - debug state funcs */ static int debug_state_print(struct dlm_ctxt *dlm, struct debug_buffer *db) { @@ -544,6 +778,17 @@ int dlm_debug_init(struct dlm_ctxt *dlm) goto bail; } + /* for dumping lockres */ + dc->debug_lockres_dentry = + debugfs_create_file(DLM_DEBUGFS_LOCKING_STATE, + S_IFREG|S_IRUSR, + dlm->dlm_debugfs_subroot, + dlm, &debug_lockres_fops); + if (!dc->debug_lockres_dentry) { + mlog_errno(-ENOMEM); + goto bail; + } + dlm_debug_get(dc); return 0; @@ -557,6 +802,8 @@ void dlm_debug_shutdown(struct dlm_ctxt *dlm) struct dlm_debug_ctxt *dc = dlm->dlm_debug_ctxt; if (dc) { + if (dc->debug_lockres_dentry) + debugfs_remove(dc->debug_lockres_dentry); if (dc->debug_state_dentry) debugfs_remove(dc->debug_state_dentry); dlm_debug_put(dc); diff --git a/fs/ocfs2/dlm/dlmdebug.h b/fs/ocfs2/dlm/dlmdebug.h index 94cc10a4e19c..7c5b2b0a05ed 100644 --- a/fs/ocfs2/dlm/dlmdebug.h +++ b/fs/ocfs2/dlm/dlmdebug.h @@ -30,6 +30,7 @@ struct dlm_debug_ctxt { struct kref debug_refcnt; struct dentry *debug_state_dentry; + struct dentry *debug_lockres_dentry; }; struct debug_buffer { @@ -37,6 +38,13 @@ struct debug_buffer { char *buf; }; +struct debug_lockres { + int dl_len; + char *dl_buf; + struct dlm_ctxt *dl_ctxt; + struct dlm_lock_resource *dl_res; +}; + int dlm_debug_init(struct dlm_ctxt *dlm); void dlm_debug_shutdown(struct dlm_ctxt *dlm);