[PATCH] libata: use WARN_ON_ONCE on hot paths
From: Tejun Heo
Date: Fri Jan 09 2009 - 05:19:53 EST
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@xxxxxxxxxx>
---
drivers/ata/libata-core.c | 16 ++++++++--------
drivers/ata/libata-sff.c | 24 ++++++++++++------------
2 files changed, 20 insertions(+), 20 deletions(-)
diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index 175df54..c507a9a 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 c59ad76..0eae9b4 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;
}
--
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