gfs2: dump fsid when dumping glock problems

Before this patch, if a glock error was encountered, the glock with
the problem was dumped. But sometimes you may have lots of file systems
mounted, and that doesn't tell you which file system it was for.

This patch adds a new boolean parameter fsid to the dump_glock family
of functions. For non-error cases, such as dumping the glocks debugfs
file, the fsid is not dumped in order to keep lock dumps and glocktop
as clean as possible. For all error cases, such as GLOCK_BUG_ON, the
file system id is now printed. This will make it easier to debug.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>

fs/gfs2/glock.c

@@ -1075,7 +1075,7 @@ __acquires(&gl->gl_lockref.lock)
 	fs_err(sdp, "pid: %d\n", pid_nr(gh->gh_owner_pid));
 	fs_err(sdp, "lock type: %d req lock state : %d\n",
 	       gh->gh_gl->gl_name.ln_type, gh->gh_state);
-	gfs2_dump_glock(NULL, gl);
+	gfs2_dump_glock(NULL, gl, true);
 	BUG();
 }
 
@@ -1610,16 +1610,16 @@ void gfs2_glock_thaw(struct gfs2_sbd *sdp)
 	glock_hash_walk(thaw_glock, sdp);
 }
 
-static void dump_glock(struct seq_file *seq, struct gfs2_glock *gl)
+static void dump_glock(struct seq_file *seq, struct gfs2_glock *gl, bool fsid)
 {
 	spin_lock(&gl->gl_lockref.lock);
-	gfs2_dump_glock(seq, gl);
+	gfs2_dump_glock(seq, gl, fsid);
 	spin_unlock(&gl->gl_lockref.lock);
 }
 
 static void dump_glock_func(struct gfs2_glock *gl)
 {
-	dump_glock(NULL, gl);
+	dump_glock(NULL, gl, true);
 }
 
 /**
@@ -1704,10 +1704,12 @@ static const char *hflags2str(char *buf, u16 flags, unsigned long iflags)
  * dump_holder - print information about a glock holder
  * @seq: the seq_file struct
  * @gh: the glock holder
+ * @fs_id_buf: pointer to file system id (if requested)
  *
  */
 
-static void dump_holder(struct seq_file *seq, const struct gfs2_holder *gh)
+static void dump_holder(struct seq_file *seq, const struct gfs2_holder *gh,
+			const char *fs_id_buf)
 {
 	struct task_struct *gh_owner = NULL;
 	char flags_buf[32];
@@ -1715,8 +1717,8 @@ static void dump_holder(struct seq_file *seq, const struct gfs2_holder *gh)
 	rcu_read_lock();
 	if (gh->gh_owner_pid)
 		gh_owner = pid_task(gh->gh_owner_pid, PIDTYPE_PID);
-	gfs2_print_dbg(seq, " H: s:%s f:%s e:%d p:%ld [%s] %pS\n",
-		       state2str(gh->gh_state),
+	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,
@@ -1766,6 +1768,7 @@ static const char *gflags2str(char *buf, const struct gfs2_glock *gl)
  * gfs2_dump_glock - print information about a glock
  * @seq: The seq_file struct
  * @gl: the glock
+ * @fsid: If true, also dump the file system id
  *
  * The file format is as follows:
  * One line per object, capital letters are used to indicate objects
@@ -1779,19 +1782,24 @@ static const char *gflags2str(char *buf, const struct gfs2_glock *gl)
  *
  */
 
-void gfs2_dump_glock(struct seq_file *seq, struct gfs2_glock *gl)
+void gfs2_dump_glock(struct seq_file *seq, struct gfs2_glock *gl, bool fsid)
 {
 	const struct gfs2_glock_operations *glops = gl->gl_ops;
 	unsigned long long dtime;
 	const struct gfs2_holder *gh;
 	char gflags_buf[32];
+	char fs_id_buf[GFS2_FSNAME_LEN + 3 * sizeof(int) + 2];
+	struct gfs2_sbd *sdp = gl->gl_name.ln_sbd;
 
+	memset(fs_id_buf, 0, sizeof(fs_id_buf));
+	if (fsid && sdp) /* safety precaution */
+		sprintf(fs_id_buf, "fsid=%s: ", sdp->sd_fsname);
 	dtime = jiffies - gl->gl_demote_time;
 	dtime *= 1000000/HZ; /* demote time in uSec */
 	if (!test_bit(GLF_DEMOTE, &gl->gl_flags))
 		dtime = 0;
-	gfs2_print_dbg(seq, "G:  s:%s n:%u/%llx f:%s t:%s d:%s/%llu a:%d v:%d r:%d m:%ld\n",
-		  state2str(gl->gl_state),
+	gfs2_print_dbg(seq, "%sG:  s:%s n:%u/%llx f:%s t:%s d:%s/%llu a:%d "
+		       "v:%d r:%d m:%ld\n", fs_id_buf, state2str(gl->gl_state),
 		  gl->gl_name.ln_type,
 		  (unsigned long long)gl->gl_name.ln_number,
 		  gflags2str(gflags_buf, gl),
@@ -1802,10 +1810,10 @@ void gfs2_dump_glock(struct seq_file *seq, struct gfs2_glock *gl)
 		  (int)gl->gl_lockref.count, gl->gl_hold_time);
 
 	list_for_each_entry(gh, &gl->gl_holders, gh_list)
-		dump_holder(seq, gh);
+		dump_holder(seq, gh, fs_id_buf);
 
 	if (gl->gl_state != LM_ST_UNLOCKED && glops->go_dump)
-		glops->go_dump(seq, gl);
+		glops->go_dump(seq, gl, fs_id_buf);
 }
 
 static int gfs2_glstats_seq_show(struct seq_file *seq, void *iter_ptr)
@@ -2006,7 +2014,7 @@ static void gfs2_glock_seq_stop(struct seq_file *seq, void *iter_ptr)
 
 static int gfs2_glock_seq_show(struct seq_file *seq, void *iter_ptr)
 {
-	dump_glock(seq, iter_ptr);
+	dump_glock(seq, iter_ptr, false);
 	return 0;
 }
 

fs/gfs2/glock.h

@@ -199,8 +199,11 @@ extern int gfs2_glock_nq_num(struct gfs2_sbd *sdp, u64 number,
 			     struct gfs2_holder *gh);
 extern int gfs2_glock_nq_m(unsigned int num_gh, struct gfs2_holder *ghs);
 extern void gfs2_glock_dq_m(unsigned int num_gh, struct gfs2_holder *ghs);
-extern void gfs2_dump_glock(struct seq_file *seq, struct gfs2_glock *gl);
-#define GLOCK_BUG_ON(gl,x) do { if (unlikely(x)) { gfs2_dump_glock(NULL, gl); BUG(); } } while(0)
+extern void gfs2_dump_glock(struct seq_file *seq, struct gfs2_glock *gl,
+			    bool fsid);
+#define GLOCK_BUG_ON(gl,x) do { if (unlikely(x)) {		\
+			gfs2_dump_glock(NULL, gl, true);	\
+			BUG(); } } while(0)
 extern __printf(2, 3)
 void gfs2_print_dbg(struct seq_file *seq, const char *fmt, ...);
 
@@ -266,7 +269,7 @@ static inline void glock_set_object(struct gfs2_glock *gl, void *object)
 {
 	spin_lock(&gl->gl_lockref.lock);
 	if (gfs2_assert_warn(gl->gl_name.ln_sbd, gl->gl_object == NULL))
-		gfs2_dump_glock(NULL, gl);
+		gfs2_dump_glock(NULL, gl, true);
 	gl->gl_object = object;
 	spin_unlock(&gl->gl_lockref.lock);
 }
@@ -278,7 +281,7 @@ static inline void glock_set_object(struct gfs2_glock *gl, void *object)
  *
  * I'd love to similarly add this:
  *	else if (gfs2_assert_warn(gl->gl_sbd, gl->gl_object == object))
- *		gfs2_dump_glock(NULL, gl);
+ *		gfs2_dump_glock(NULL, gl, true);
  * Unfortunately, that's not possible because as soon as gfs2_delete_inode
  * frees the block in the rgrp, another process can reassign it for an I_NEW
  * inode in gfs2_create_inode because that calls new_inode, not gfs2_iget.

fs/gfs2/glops.c

@@ -461,10 +461,12 @@ static int inode_go_lock(struct gfs2_holder *gh)
  * inode_go_dump - print information about an inode
  * @seq: The iterator
  * @ip: the inode
+ * @fs_id_buf: file system id (may be empty)
  *
  */
 
-static void inode_go_dump(struct seq_file *seq, struct gfs2_glock *gl)
+static void inode_go_dump(struct seq_file *seq, struct gfs2_glock *gl,
+			  const char *fs_id_buf)
 {
 	struct gfs2_inode *ip = gl->gl_object;
 	struct inode *inode = &ip->i_inode;
@@ -477,7 +479,8 @@ static void inode_go_dump(struct seq_file *seq, struct gfs2_glock *gl)
 	nrpages = inode->i_data.nrpages;
 	xa_unlock_irq(&inode->i_data.i_pages);
 
-	gfs2_print_dbg(seq, " I: n:%llu/%llu t:%u f:0x%02lx d:0x%08x s:%llu p:%lu\n",
+	gfs2_print_dbg(seq, "%s I: n:%llu/%llu t:%u f:0x%02lx d:0x%08x s:%llu "
+		       "p:%lu\n", fs_id_buf,
 		  (unsigned long long)ip->i_no_formal_ino,
 		  (unsigned long long)ip->i_no_addr,
 		  IF2DT(ip->i_inode.i_mode), ip->i_flags,

fs/gfs2/incore.h

@@ -240,7 +240,8 @@ struct gfs2_glock_operations {
 	int (*go_demote_ok) (const struct gfs2_glock *gl);
 	int (*go_lock) (struct gfs2_holder *gh);
 	void (*go_unlock) (struct gfs2_holder *gh);
-	void (*go_dump)(struct seq_file *seq, struct gfs2_glock *gl);
+	void (*go_dump)(struct seq_file *seq, struct gfs2_glock *gl,
+			const char *fs_id_buf);
 	void (*go_callback)(struct gfs2_glock *gl, bool remote);
 	const int go_type;
 	const unsigned long go_flags;

fs/gfs2/lops.c

@@ -775,7 +775,7 @@ static int buf_lo_scan_elements(struct gfs2_jdesc *jd, u32 start,
 					fs_info(sdp, "busy:%d, pinned:%d\n",
 						buffer_busy(rgd->rd_bits->bi_bh) ? 1 : 0,
 						buffer_pinned(rgd->rd_bits->bi_bh));
-					gfs2_dump_glock(NULL, rgd->rd_gl);
+					gfs2_dump_glock(NULL, rgd->rd_gl, true);
 				}
 			}
 			mark_buffer_dirty(bh_ip);

fs/gfs2/rgrp.c

@@ -610,11 +610,12 @@ int gfs2_rsqa_alloc(struct gfs2_inode *ip)
 	return gfs2_qa_alloc(ip);
 }
 
-static void dump_rs(struct seq_file *seq, const struct gfs2_blkreserv *rs)
+static void dump_rs(struct seq_file *seq, const struct gfs2_blkreserv *rs,
+		    const char *fs_id_buf)
 {
 	struct gfs2_inode *ip = container_of(rs, struct gfs2_inode, i_res);
 
-	gfs2_print_dbg(seq, "  B: n:%llu s:%llu b:%u f:%u\n",
+	gfs2_print_dbg(seq, "%s  B: n:%llu s:%llu b:%u f:%u\n", fs_id_buf,
 		       (unsigned long long)ip->i_no_addr,
 		       (unsigned long long)gfs2_rbm_to_block(&rs->rs_rbm),
 		       rs->rs_rbm.offset, rs->rs_free);
@@ -2246,10 +2247,12 @@ static void rgblk_free(struct gfs2_sbd *sdp, struct gfs2_rgrpd *rgd,
  * gfs2_rgrp_dump - print out an rgrp
  * @seq: The iterator
  * @gl: The glock in question
+ * @fs_id_buf: pointer to file system id (if requested)
  *
  */
 
-void gfs2_rgrp_dump(struct seq_file *seq, struct gfs2_glock *gl)
+void gfs2_rgrp_dump(struct seq_file *seq, struct gfs2_glock *gl,
+		    const char *fs_id_buf)
 {
 	struct gfs2_rgrpd *rgd = gl->gl_object;
 	struct gfs2_blkreserv *trs;
@@ -2257,14 +2260,15 @@ void gfs2_rgrp_dump(struct seq_file *seq, struct gfs2_glock *gl)
 
 	if (rgd == NULL)
 		return;
-	gfs2_print_dbg(seq, " R: n:%llu f:%02x b:%u/%u i:%u r:%u e:%u\n",
+	gfs2_print_dbg(seq, "%s R: n:%llu f:%02x b:%u/%u i:%u r:%u e:%u\n",
+		       fs_id_buf,
 		       (unsigned long long)rgd->rd_addr, rgd->rd_flags,
 		       rgd->rd_free, rgd->rd_free_clone, rgd->rd_dinodes,
 		       rgd->rd_reserved, rgd->rd_extfail_pt);
 	if (rgd->rd_sbd->sd_args.ar_rgrplvb) {
 		struct gfs2_rgrp_lvb *rgl = rgd->rd_rgl;
 
-		gfs2_print_dbg(seq, "  L: f:%02x b:%u i:%u\n",
+		gfs2_print_dbg(seq, "%s  L: f:%02x b:%u i:%u\n", fs_id_buf,
 			       be32_to_cpu(rgl->rl_flags),
 			       be32_to_cpu(rgl->rl_free),
 			       be32_to_cpu(rgl->rl_dinodes));
@@ -2272,7 +2276,7 @@ void gfs2_rgrp_dump(struct seq_file *seq, struct gfs2_glock *gl)
 	spin_lock(&rgd->rd_rsspin);
 	for (n = rb_first(&rgd->rd_rstree); n; n = rb_next(&trs->rs_node)) {
 		trs = rb_entry(n, struct gfs2_blkreserv, rs_node);
-		dump_rs(seq, trs);
+		dump_rs(seq, trs, fs_id_buf);
 	}
 	spin_unlock(&rgd->rd_rsspin);
 }
@@ -2280,10 +2284,13 @@ void gfs2_rgrp_dump(struct seq_file *seq, struct gfs2_glock *gl)
 static void gfs2_rgrp_error(struct gfs2_rgrpd *rgd)
 {
 	struct gfs2_sbd *sdp = rgd->rd_sbd;
+	char fs_id_buf[GFS2_FSNAME_LEN + 3 * sizeof(int) + 2];
+
 	fs_warn(sdp, "rgrp %llu has an error, marking it readonly until umount\n",
 		(unsigned long long)rgd->rd_addr);
 	fs_warn(sdp, "umount on all nodes and run fsck.gfs2 to fix the error\n");
-	gfs2_rgrp_dump(NULL, rgd->rd_gl);
+	sprintf(fs_id_buf, "fsid=%s: ", sdp->sd_fsname);
+	gfs2_rgrp_dump(NULL, rgd->rd_gl, fs_id_buf);
 	rgd->rd_flags |= GFS2_RDF_ERROR;
 }
 

fs/gfs2/rgrp.h

@@ -69,7 +69,8 @@ extern void gfs2_rlist_add(struct gfs2_inode *ip, struct gfs2_rgrp_list *rlist,
 extern void gfs2_rlist_alloc(struct gfs2_rgrp_list *rlist);
 extern void gfs2_rlist_free(struct gfs2_rgrp_list *rlist);
 extern u64 gfs2_ri_total(struct gfs2_sbd *sdp);
-extern void gfs2_rgrp_dump(struct seq_file *seq, struct gfs2_glock *gl);
+extern void gfs2_rgrp_dump(struct seq_file *seq, struct gfs2_glock *gl,
+			   const char *fs_id_buf);
 extern int gfs2_rgrp_send_discards(struct gfs2_sbd *sdp, u64 offset,
 				   struct buffer_head *bh,
 				   const struct gfs2_bitmap *bi, unsigned minlen, u64 *ptrimmed);

fs/gfs2/util.c

@@ -178,9 +178,11 @@ int gfs2_consist_rgrpd_i(struct gfs2_rgrpd *rgd, int cluster_wide,
 			 const char *function, char *file, unsigned int line)
 {
 	struct gfs2_sbd *sdp = rgd->rd_sbd;
+	char fs_id_buf[GFS2_FSNAME_LEN + 3 * sizeof(int) + 2];
 	int rv;
 
-	gfs2_rgrp_dump(NULL, rgd->rd_gl);
+	sprintf(fs_id_buf, "fsid=%s: ", sdp->sd_fsname);
+	gfs2_rgrp_dump(NULL, rgd->rd_gl, fs_id_buf);
 	rv = gfs2_lm_withdraw(sdp,
 			      "fatal: filesystem consistency error\n"
 			      "  RG = %llu\n"