xfs: fact out common grant head/log tail verification code

Factor repeated debug code out of grant head manipulation functions into a
separate function. This removes ifdef DEBUG spagetti from the code and makes
the code easier to follow.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>

1 files changed, 22 insertions, 29 deletions

diff --git a/fs/xfs/xfs_log.c b/fs/xfs/xfs_log.c
index 1b82735471ab..99c62855432e 100644
--- a/fs/xfs/xfs_log.c
+++ b/fs/xfs/xfs_log.c
@@ -82,6 +82,7 @@ STATIC void xlog_ungrant_log_space(xlog_t	 *log,
 #if defined(DEBUG)
 STATIC void     xlog_verify_dest_ptr(xlog_t *log, char *ptr);
 STATIC void     xlog_verify_grant_head(xlog_t *log, int equals);
+STATIC void     xlog_verify_grant_tail(struct log *log);
 STATIC void     xlog_verify_iclog(xlog_t *log, xlog_in_core_t *iclog,
                                   int count, boolean_t syncing);
 STATIC void     xlog_verify_tail_lsn(xlog_t *log, xlog_in_core_t *iclog,
@@ -89,6 +90,7 @@ STATIC void	xlog_verify_tail_lsn(xlog_t *log, xlog_in_core_t *iclog,
 #else
 #define xlog_verify_dest_ptr(a,b)
 #define xlog_verify_grant_head(a,b)
+#define xlog_verify_grant_tail(a)
 #define xlog_verify_iclog(a,b,c,d)
 #define xlog_verify_tail_lsn(a,b,c)
 #endif
@@ -2503,10 +2505,6 @@ xlog_grant_log_space(xlog_t	   *log,
 {
         int              free_bytes;
         int              need_bytes;
-#ifdef DEBUG
-        xfs_lsn_t        tail_lsn;
-#endif
-
 
 #ifdef DEBUG
         if (log->l_flags & XLOG_ACTIVE_RECOVERY)
@@ -2577,21 +2575,9 @@ redo:
 
         /* we've got enough space */
         xlog_grant_add_space(log, need_bytes);
-#ifdef DEBUG
-        tail_lsn = log->l_tail_lsn;
-        /*
-         * Check to make sure the grant write head didn't just over lap the
-         * tail.  If the cycles are the same, we can't be overlapping.
-         * Otherwise, make sure that the cycles differ by exactly one and
-         * check the byte count.
-         */
-        if (CYCLE_LSN(tail_lsn) != log->l_grant_write_cycle) {
-                ASSERT(log->l_grant_write_cycle-1 == CYCLE_LSN(tail_lsn));
-                ASSERT(log->l_grant_write_bytes <= BBTOB(BLOCK_LSN(tail_lsn)));
-        }
-#endif
         trace_xfs_log_grant_exit(log, tic);
         xlog_verify_grant_head(log, 1);
+        xlog_verify_grant_tail(log);
         spin_unlock(&log->l_grant_lock);
         return 0;
 
@@ -2621,9 +2607,6 @@ xlog_regrant_write_log_space(xlog_t	   *log,
                              xlog_ticket_t *tic)
 {
         int             free_bytes, need_bytes;
-#ifdef DEBUG
-        xfs_lsn_t       tail_lsn;
-#endif
 
         tic->t_curr_res = tic->t_unit_res;
         xlog_tic_reset_res(tic);
@@ -2719,17 +2702,9 @@ redo:
 
         /* we've got enough space */
         xlog_grant_add_space_write(log, need_bytes);
-#ifdef DEBUG
-        tail_lsn = log->l_tail_lsn;
-        if (CYCLE_LSN(tail_lsn) != log->l_grant_write_cycle) {
-                ASSERT(log->l_grant_write_cycle-1 == CYCLE_LSN(tail_lsn));
-                ASSERT(log->l_grant_write_bytes <= BBTOB(BLOCK_LSN(tail_lsn)));
-        }
-#endif
-
         trace_xfs_log_regrant_write_exit(log, tic);
-
         xlog_verify_grant_head(log, 1);
+        xlog_verify_grant_tail(log);
         spin_unlock(&log->l_grant_lock);
         return 0;
 
@@ -3465,6 +3440,24 @@ xlog_verify_grant_head(xlog_t *log, int equals)
     }
 }       /* xlog_verify_grant_head */
 
+STATIC void
+xlog_verify_grant_tail(
+        struct log      *log)
+{
+        xfs_lsn_t       tail_lsn = log->l_tail_lsn;
+
+        /*
+         * Check to make sure the grant write head didn't just over lap the
+         * tail.  If the cycles are the same, we can't be overlapping.
+         * Otherwise, make sure that the cycles differ by exactly one and
+         * check the byte count.
+         */
+        if (CYCLE_LSN(tail_lsn) != log->l_grant_write_cycle) {
+                ASSERT(log->l_grant_write_cycle - 1 == CYCLE_LSN(tail_lsn));
+                ASSERT(log->l_grant_write_bytes <= BBTOB(BLOCK_LSN(tail_lsn)));
+        }
+}
+
 /* check if it will fit */
 STATIC void
 xlog_verify_tail_lsn(xlog_t         *log,