libata: use WARN_ON_ONCE on hot paths

Convert WARN_ON() on command issue/completion paths to WARN_ON_ONCE()
so that libata doesn't spam the machine even when one of those
conditions triggers repeatedly.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2 files changed, 20 insertions, 20 deletions

diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index 175df54eb664..c507a9ac78f4 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -4556,7 +4556,7 @@ void ata_sg_clean(struct ata_queued_cmd *qc)
         struct scatterlist *sg = qc->sg;
         int dir = qc->dma_dir;
 
-        WARN_ON(sg == NULL);
+        WARN_ON_ONCE(sg == NULL);
 
         VPRINTK("unmapping %u sg elements\n", qc->n_elem);
 
@@ -4776,7 +4776,7 @@ void ata_qc_free(struct ata_queued_cmd *qc)
         struct ata_port *ap = qc->ap;
         unsigned int tag;
 
-        WARN_ON(qc == NULL);    /* ata_qc_from_tag _might_ return NULL */
+        WARN_ON_ONCE(qc == NULL); /* ata_qc_from_tag _might_ return NULL */
 
         qc->flags = 0;
         tag = qc->tag;
@@ -4791,8 +4791,8 @@ void __ata_qc_complete(struct ata_queued_cmd *qc)
         struct ata_port *ap = qc->ap;
         struct ata_link *link = qc->dev->link;
 
-        WARN_ON(qc == NULL);    /* ata_qc_from_tag _might_ return NULL */
-        WARN_ON(!(qc->flags & ATA_QCFLAG_ACTIVE));
+        WARN_ON_ONCE(qc == NULL); /* ata_qc_from_tag _might_ return NULL */
+        WARN_ON_ONCE(!(qc->flags & ATA_QCFLAG_ACTIVE));
 
         if (likely(qc->flags & ATA_QCFLAG_DMAMAP))
                 ata_sg_clean(qc);
@@ -4878,7 +4878,7 @@ void ata_qc_complete(struct ata_queued_cmd *qc)
                 struct ata_device *dev = qc->dev;
                 struct ata_eh_info *ehi = &dev->link->eh_info;
 
-                WARN_ON(ap->pflags & ATA_PFLAG_FROZEN);
+                WARN_ON_ONCE(ap->pflags & ATA_PFLAG_FROZEN);
 
                 if (unlikely(qc->err_mask))
                         qc->flags |= ATA_QCFLAG_FAILED;
@@ -5000,16 +5000,16 @@ void ata_qc_issue(struct ata_queued_cmd *qc)
          * check is skipped for old EH because it reuses active qc to
          * request ATAPI sense.
          */
-        WARN_ON(ap->ops->error_handler && ata_tag_valid(link->active_tag));
+        WARN_ON_ONCE(ap->ops->error_handler && ata_tag_valid(link->active_tag));
 
         if (ata_is_ncq(prot)) {
-                WARN_ON(link->sactive & (1 << qc->tag));
+                WARN_ON_ONCE(link->sactive & (1 << qc->tag));
 
                 if (!link->sactive)
                         ap->nr_active_links++;
                 link->sactive |= 1 << qc->tag;
         } else {
-                WARN_ON(link->sactive);
+                WARN_ON_ONCE(link->sactive);
 
                 ap->nr_active_links++;
                 link->active_tag = qc->tag;
diff --git a/drivers/ata/libata-sff.c b/drivers/ata/libata-sff.c
index c59ad76c84b1..0eae9b453556 100644
--- a/drivers/ata/libata-sff.c
+++ b/drivers/ata/libata-sff.c
@@ -578,7 +578,7 @@ void ata_sff_tf_load(struct ata_port *ap, const struct ata_taskfile *tf)
         }
 
         if (is_addr && (tf->flags & ATA_TFLAG_LBA48)) {
-                WARN_ON(!ioaddr->ctl_addr);
+                WARN_ON_ONCE(!ioaddr->ctl_addr);
                 iowrite8(tf->hob_feature, ioaddr->feature_addr);
                 iowrite8(tf->hob_nsect, ioaddr->nsect_addr);
                 iowrite8(tf->hob_lbal, ioaddr->lbal_addr);
@@ -651,7 +651,7 @@ void ata_sff_tf_read(struct ata_port *ap, struct ata_taskfile *tf)
                         iowrite8(tf->ctl, ioaddr->ctl_addr);
                         ap->last_ctl = tf->ctl;
                 } else
-                        WARN_ON(1);
+                        WARN_ON_ONCE(1);
         }
 }
 EXPORT_SYMBOL_GPL(ata_sff_tf_read);
@@ -891,7 +891,7 @@ static void ata_pio_sectors(struct ata_queued_cmd *qc)
                 /* READ/WRITE MULTIPLE */
                 unsigned int nsect;
 
-                WARN_ON(qc->dev->multi_count == 0);
+                WARN_ON_ONCE(qc->dev->multi_count == 0);
 
                 nsect = min((qc->nbytes - qc->curbytes) / qc->sect_size,
                             qc->dev->multi_count);
@@ -918,7 +918,7 @@ static void atapi_send_cdb(struct ata_port *ap, struct ata_queued_cmd *qc)
 {
         /* send SCSI cdb */
         DPRINTK("send cdb\n");
-        WARN_ON(qc->dev->cdb_len < 12);
+        WARN_ON_ONCE(qc->dev->cdb_len < 12);
 
         ap->ops->sff_data_xfer(qc->dev, qc->cdb, qc->dev->cdb_len, 1);
         ata_sff_sync(ap);
@@ -1014,7 +1014,7 @@ next_sg:
         }
 
         /* consumed can be larger than count only for the last transfer */
-        WARN_ON(qc->cursg && count != consumed);
+        WARN_ON_ONCE(qc->cursg && count != consumed);
 
         if (bytes)
                 goto next_sg;
@@ -1172,13 +1172,13 @@ int ata_sff_hsm_move(struct ata_port *ap, struct ata_queued_cmd *qc,
         unsigned long flags = 0;
         int poll_next;
 
-        WARN_ON((qc->flags & ATA_QCFLAG_ACTIVE) == 0);
+        WARN_ON_ONCE((qc->flags & ATA_QCFLAG_ACTIVE) == 0);
 
         /* Make sure ata_sff_qc_issue() does not throw things
          * like DMA polling into the workqueue. Notice that
          * in_wq is not equivalent to (qc->tf.flags & ATA_TFLAG_POLLING).
          */
-        WARN_ON(in_wq != ata_hsm_ok_in_wq(ap, qc));
+        WARN_ON_ONCE(in_wq != ata_hsm_ok_in_wq(ap, qc));
 
 fsm_start:
         DPRINTK("ata%u: protocol %d task_state %d (dev_stat 0x%X)\n",
@@ -1387,7 +1387,7 @@ fsm_start:
                 DPRINTK("ata%u: dev %u command complete, drv_stat 0x%x\n",
                         ap->print_id, qc->dev->devno, status);
 
-                WARN_ON(qc->err_mask & (AC_ERR_DEV | AC_ERR_HSM));
+                WARN_ON_ONCE(qc->err_mask & (AC_ERR_DEV | AC_ERR_HSM));
 
                 ap->hsm_task_state = HSM_ST_IDLE;
 
@@ -1423,7 +1423,7 @@ void ata_pio_task(struct work_struct *work)
         int poll_next;
 
 fsm_start:
-        WARN_ON(ap->hsm_task_state == HSM_ST_IDLE);
+        WARN_ON_ONCE(ap->hsm_task_state == HSM_ST_IDLE);
 
         /*
          * This is purely heuristic.  This is a fast path.
@@ -1512,7 +1512,7 @@ unsigned int ata_sff_qc_issue(struct ata_queued_cmd *qc)
                 break;
 
         case ATA_PROT_DMA:
-                WARN_ON(qc->tf.flags & ATA_TFLAG_POLLING);
+                WARN_ON_ONCE(qc->tf.flags & ATA_TFLAG_POLLING);
 
                 ap->ops->sff_tf_load(ap, &qc->tf);  /* load tf registers */
                 ap->ops->bmdma_setup(qc);           /* set up bmdma */
@@ -1564,7 +1564,7 @@ unsigned int ata_sff_qc_issue(struct ata_queued_cmd *qc)
                 break;
 
         case ATAPI_PROT_DMA:
-                WARN_ON(qc->tf.flags & ATA_TFLAG_POLLING);
+                WARN_ON_ONCE(qc->tf.flags & ATA_TFLAG_POLLING);
 
                 ap->ops->sff_tf_load(ap, &qc->tf);  /* load tf registers */
                 ap->ops->bmdma_setup(qc);           /* set up bmdma */
@@ -1576,7 +1576,7 @@ unsigned int ata_sff_qc_issue(struct ata_queued_cmd *qc)
                 break;
 
         default:
-                WARN_ON(1);
+                WARN_ON_ONCE(1);
                 return AC_ERR_SYSTEM;
         }