xfs: replace log_badcrc_factor knob with error injection tag

Now that error injection tags support dynamic frequency adjustment,
replace the debug mode sysfs knob that controls log record CRC error
injection with an error injection tag.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>

fs/xfs/xfs_error.c

@@ -56,6 +56,7 @@ static unsigned int xfs_errortag_random_default[] = {
 	XFS_RANDOM_BMAP_FINISH_ONE,
 	XFS_RANDOM_AG_RESV_CRITICAL,
 	XFS_RANDOM_DROP_WRITES,
+	XFS_RANDOM_LOG_BAD_CRC,
 };
 
 struct xfs_errortag_attr {
@@ -159,6 +160,7 @@ XFS_ERRORTAG_ATTR_RW(refcount_finish_one,	XFS_ERRTAG_REFCOUNT_FINISH_ONE);
 XFS_ERRORTAG_ATTR_RW(bmap_finish_one,	XFS_ERRTAG_BMAP_FINISH_ONE);
 XFS_ERRORTAG_ATTR_RW(ag_resv_critical,	XFS_ERRTAG_AG_RESV_CRITICAL);
 XFS_ERRORTAG_ATTR_RW(drop_writes,	XFS_ERRTAG_DROP_WRITES);
+XFS_ERRORTAG_ATTR_RW(log_bad_crc,	XFS_ERRTAG_LOG_BAD_CRC);
 
 static struct attribute *xfs_errortag_attrs[] = {
 	XFS_ERRORTAG_ATTR_LIST(noerror),
@@ -190,6 +192,7 @@ static struct attribute *xfs_errortag_attrs[] = {
 	XFS_ERRORTAG_ATTR_LIST(bmap_finish_one),
 	XFS_ERRORTAG_ATTR_LIST(ag_resv_critical),
 	XFS_ERRORTAG_ATTR_LIST(drop_writes),
+	XFS_ERRORTAG_ATTR_LIST(log_bad_crc),
 	NULL,
 };
 

fs/xfs/xfs_error.h

@@ -105,7 +105,8 @@ extern void xfs_verifier_error(struct xfs_buf *bp);
  * handling sequence.
  */
 #define XFS_ERRTAG_DROP_WRITES				28
-#define XFS_ERRTAG_MAX					29
+#define XFS_ERRTAG_LOG_BAD_CRC				29
+#define XFS_ERRTAG_MAX					30
 
 /*
  * Random factors for above tags, 1 means always, 2 means 1/2 time, etc.
@@ -139,6 +140,7 @@ extern void xfs_verifier_error(struct xfs_buf *bp);
 #define XFS_RANDOM_BMAP_FINISH_ONE			1
 #define XFS_RANDOM_AG_RESV_CRITICAL			4
 #define XFS_RANDOM_DROP_WRITES				1
+#define XFS_RANDOM_LOG_BAD_CRC				1
 
 #ifdef DEBUG
 extern int xfs_errortag_init(struct xfs_mount *mp);

fs/xfs/xfs_log.c

@@ -1841,7 +1841,6 @@ xlog_sync(
 	/* calculcate the checksum */
 	iclog->ic_header.h_crc = xlog_cksum(log, &iclog->ic_header,
 					    iclog->ic_datap, size);
-#ifdef DEBUG
 	/*
 	 * Intentionally corrupt the log record CRC based on the error injection
 	 * frequency, if defined. This facilitates testing log recovery in the
@@ -1849,15 +1848,13 @@ xlog_sync(
 	 * write on I/O completion and shutdown the fs. The subsequent mount
 	 * detects the bad CRC and attempts to recover.
 	 */
-	if (log->l_badcrc_factor &&
-	    (prandom_u32() % log->l_badcrc_factor == 0)) {
+	if (XFS_TEST_ERROR(false, log->l_mp, XFS_ERRTAG_LOG_BAD_CRC)) {
 		iclog->ic_header.h_crc &= cpu_to_le32(0xAAAAAAAA);
 		iclog->ic_state |= XLOG_STATE_IOABORT;
 		xfs_warn(log->l_mp,
 	"Intentionally corrupted log record at LSN 0x%llx. Shutdown imminent.",
 			 be64_to_cpu(iclog->ic_header.h_lsn));
 	}
-#endif
 
 	bp->b_io_length = BTOBB(count);
 	bp->b_fspriv = iclog;

fs/xfs/xfs_sysfs.c

@@ -305,47 +305,11 @@ write_grant_head_show(
 }
 XFS_SYSFS_ATTR_RO(write_grant_head);
 
-#ifdef DEBUG
-STATIC ssize_t
-log_badcrc_factor_store(
-	struct kobject	*kobject,
-	const char	*buf,
-	size_t		count)
-{
-	struct xlog	*log = to_xlog(kobject);
-	int		ret;
-	uint32_t	val;
-
-	ret = kstrtouint(buf, 0, &val);
-	if (ret)
-		return ret;
-
-	log->l_badcrc_factor = val;
-
-	return count;
-}
-
-STATIC ssize_t
-log_badcrc_factor_show(
-	struct kobject	*kobject,
-	char		*buf)
-{
-	struct xlog	*log = to_xlog(kobject);
-
-	return snprintf(buf, PAGE_SIZE, "%d\n", log->l_badcrc_factor);
-}
-
-XFS_SYSFS_ATTR_RW(log_badcrc_factor);
-#endif	/* DEBUG */
-
 static struct attribute *xfs_log_attrs[] = {
 	ATTR_LIST(log_head_lsn),
 	ATTR_LIST(log_tail_lsn),
 	ATTR_LIST(reserve_grant_head),
 	ATTR_LIST(write_grant_head),
-#ifdef DEBUG
-	ATTR_LIST(log_badcrc_factor),
-#endif
 	NULL,
 };