From: Mike Snitzer <snitzer@redhat.com>

Throttle all errors logged from the IO path by dm thin.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>

---
 drivers/md/dm-thin.c |   25 +++++++++++++++----------
 1 file changed, 15 insertions(+), 10 deletions(-)

Index: linux/drivers/md/dm-thin.c
===================================================================
--- linux.orig/drivers/md/dm-thin.c
+++ linux/drivers/md/dm-thin.c
@@ -567,7 +567,7 @@ static void process_prepared_mapping(str
 	 */
 	r = dm_thin_insert_block(tc->td, m->virt_block, m->data_block);
 	if (r) {
-		DMERR("dm_thin_insert_block() failed");
+		DMERR_LIMIT("dm_thin_insert_block() failed");
 		dm_cell_error(m->cell);
 		goto out;
 	}
@@ -622,7 +622,7 @@ static void process_prepared_discard(str
 
 	r = dm_thin_remove_block(tc->td, m->virt_block);
 	if (r)
-		DMERR("dm_thin_remove_block() failed");
+		DMERR_LIMIT("dm_thin_remove_block() failed");
 
 	process_prepared_discard_passdown(m);
 }
@@ -736,7 +736,7 @@ static void schedule_copy(struct thin_c 
 				   0, copy_complete, m);
 		if (r < 0) {
 			mempool_free(m, pool->mapping_pool);
-			DMERR("dm_kcopyd_copy() failed");
+			DMERR_LIMIT("dm_kcopyd_copy() failed");
 			dm_cell_error(cell);
 		}
 	}
@@ -802,7 +802,7 @@ static void schedule_zero(struct thin_c 
 		r = dm_kcopyd_zero(pool->copier, 1, &to, 0, copy_complete, m);
 		if (r < 0) {
 			mempool_free(m, pool->mapping_pool);
-			DMERR("dm_kcopyd_zero() failed");
+			DMERR_LIMIT("dm_kcopyd_zero() failed");
 			dm_cell_error(cell);
 		}
 	}
@@ -814,7 +814,7 @@ static int commit(struct pool *pool)
 
 	r = dm_pool_commit_metadata(pool->pmd);
 	if (r)
-		DMERR("commit failed, error = %d", r);
+		DMERR_LIMIT("commit failed: error = %d", r);
 
 	return r;
 }
@@ -997,7 +997,8 @@ static void process_discard(struct thin_
 		break;
 
 	default:
-		DMERR("discard: find block unexpectedly returned %d", r);
+		DMERR_LIMIT("%s: dm_thin_find_block() failed: error = %d",
+			    __func__, r);
 		cell_defer_no_holder(tc, cell);
 		bio_io_error(bio);
 		break;
@@ -1024,7 +1025,8 @@ static void break_sharing(struct thin_c 
 		break;
 
 	default:
-		DMERR("%s: alloc_data_block() failed, error = %d", __func__, r);
+		DMERR_LIMIT("%s: alloc_data_block() failed: error = %d",
+			    __func__, r);
 		dm_cell_error(cell);
 		break;
 	}
@@ -1100,7 +1102,8 @@ static void provision_block(struct thin_
 		break;
 
 	default:
-		DMERR("%s: alloc_data_block() failed, error = %d", __func__, r);
+		DMERR_LIMIT("%s: alloc_data_block() failed: error = %d",
+			    __func__, r);
 		set_pool_mode(tc->pool, PM_READ_ONLY);
 		dm_cell_error(cell);
 		break;
@@ -1148,7 +1151,8 @@ static void process_bio(struct thin_c *t
 		break;
 
 	default:
-		DMERR("dm_thin_find_block() failed, error = %d", r);
+		DMERR_LIMIT("%s: dm_thin_find_block() failed: error = %d",
+			    __func__, r);
 		cell_defer_no_holder(tc, cell);
 		bio_io_error(bio);
 		break;
@@ -1190,7 +1194,8 @@ static void process_bio_read_only(struct
 		break;
 
 	default:
-		DMERR("dm_thin_find_block() failed, error = %d", r);
+		DMERR_LIMIT("%s: dm_thin_find_block() failed: error = %d",
+			    __func__, r);
 		bio_io_error(bio);
 		break;
 	}