xfs log recovery delay instrumentation

index b194652..919a64c 100644
@@ -47,6 +47,7 @@
 #include "xfs_dinode.h"
 #include "xfs_filestream.h"
 #include "xfs_quota.h"
+#include "xfs_sysfs.h"
 
 #include <linux/namei.h>
 #include <linux/init.h>

@@ -61,7 +62,11 @@
 static const struct super_operations xfs_super_operations;
 static kmem_zone_t *xfs_ioend_zone;
 mempool_t *xfs_ioend_pool;
-struct kset *xfs_kset;
+
+struct kset *xfs_kset;			/* top-level xfs sysfs dir */
+#ifdef DEBUG
+static struct xfs_kobj xfs_dbg_kobj;	/* global debug sysfs attrs */
+#endif
 
 #define MNTOPT_LOGBUFS	"logbufs"	/* number of XFS log buffers */
 #define MNTOPT_LOGBSIZE	"logbsize"	/* size of XFS log buffers */

@@ -1768,9 +1773,16 @@ init_xfs_fs(void)
 		goto out_sysctl_unregister;;
 	}
 
-	error = xfs_qm_init();
+#ifdef DEBUG
+	xfs_dbg_kobj.kobject.kset = xfs_kset;
+	error = xfs_sysfs_init(&xfs_dbg_kobj, &xfs_dbg_ktype, NULL, "debug");
 	if (error)
 		goto out_kset_unregister;
+#endif
+
+	error = xfs_qm_init();
+	if (error)
+		goto out_remove_kobj;
 
 	error = register_filesystem(&xfs_fs_type);
 	if (error)

@@ -1779,7 +1791,11 @@ init_xfs_fs(void)
 
  out_qm_exit:
 	xfs_qm_exit();
+ out_remove_kobj:
+#ifdef DEBUG
+	xfs_sysfs_del(&xfs_dbg_kobj);
  out_kset_unregister:
+#endif
 	kset_unregister(xfs_kset);
  out_sysctl_unregister:
 	xfs_sysctl_unregister();

@@ -1802,6 +1818,9 @@ exit_xfs_fs(void)
 {
 	xfs_qm_exit();
 	unregister_filesystem(&xfs_fs_type);
+#ifdef DEBUG
+	xfs_sysfs_del(&xfs_dbg_kobj);
+#endif
 	kset_unregister(xfs_kset);
 	xfs_sysctl_unregister();
 	xfs_cleanup_procfs();

49 lines not on this page · raw message

index 54a2091..240eee3 100644
@@ -20,6 +20,7 @@
 #define __XFS_SYSFS_H__
 
 extern struct kobj_type xfs_mp_ktype;	/* xfs_mount */
+extern struct kobj_type xfs_dbg_ktype;	/* debug */
 extern struct kobj_type xfs_log_ktype;	/* xlog */
 
 static inline struct xfs_kobj *

index 5399ef2..4d41b24 100644
@@ -43,3 +43,7 @@ xfs_param_t xfs_params = {
 	.fstrm_timer	= {	1,		30*100,		3600*100},
 	.eofb_timer	= {	1,		300,		3600*24},
 };
+
+struct xfs_globals xfs_globals = {
+	.log_recovery_delay	=	0,	/* no delay by default */
+};

index 1fd5787..176c4b3 100644
@@ -4509,6 +4509,18 @@ xlog_recover(
 			return -EINVAL;
 		}
 
+		/*
+		 * Delay log recovery if the debug hook is set. This is debug
+		 * instrumention to coordinate simulation of I/O failures with
+		 * log recovery.
+		 */
+		if (xfs_globals.log_recovery_delay) {
+			xfs_notice(log->l_mp,
+				"Delaying log recovery for %d seconds.",
+				xfs_globals.log_recovery_delay);
+			msleep(xfs_globals.log_recovery_delay * 1000);
+		}
+
 		xfs_notice(log->l_mp, "Starting recovery (logdev: %s)",
 				log->l_mp->m_logname ? log->l_mp->m_logname
 						     : "internal");

index bd8e157..ffef453 100644
@@ -92,6 +92,11 @@ enum {
 
 extern xfs_param_t	xfs_params;
 
+struct xfs_globals {
+	int	log_recovery_delay;	/* log recovery delay (secs) */
+};
+extern struct xfs_globals	xfs_globals;
+
 #ifdef CONFIG_SYSCTL
 extern int xfs_sysctl_register(void);
 extern void xfs_sysctl_unregister(void);

index 32ddf0c..aa03670 100644
@@ -54,7 +54,38 @@ struct kobj_type xfs_mp_ktype = {
 #ifdef DEBUG
 /* debug */
 
+STATIC ssize_t
+log_recovery_delay_store(
+	const char	*buf,
+	size_t		count,
+	void		*data)
+{
+	int		ret;
+	int		val;
+
+	ret = kstrtoint(buf, 0, &val);
+	if (ret)
+		return ret;
+
+	if (val < 0 || val > 60)
+		return -EINVAL;
+
+	xfs_globals.log_recovery_delay = val;
+
+	return count;
+}
+
+STATIC ssize_t
+log_recovery_delay_show(
+	char	*buf,
+	void	*data)
+{
+	return snprintf(buf, PAGE_SIZE, "%d\n", xfs_globals.log_recovery_delay);
+}
+XFS_SYSFS_ATTR_RW(log_recovery_delay);
+
 static struct attribute *xfs_dbg_attrs[] = {
+	ATTR_LIST(log_recovery_delay),
 	NULL,
 };