Commit e30349d2 authored by Tejun Heo's avatar Tejun Heo Committed by Jeff Garzik
Browse files

[PATCH] libata: replace ap_lock w/ ap->lock in ata_scsi_error() 



ap_lock was used because &ap->host_set->lock was too long and used a
lot.  Now that &ap->host_set->lock is replaced with ap->lock, there's
no reason to keep ap_lock.

[ed. note: that's not entirely true.  ap_lock is a local variable,
caching the results of a de-ref.  In theory, if the compiler is smart
enough, this patch is cosmetic.  However, since this is not a fast
path (it is the error path), this patch is nonetheless acceptable,
even though it _may_ introduce a performance regression.]

Signed-off-by: default avatarTejun Heo <htejun@gmail.com>
Signed-off-by: default avatarJeff Garzik <jeff@garzik.org>
parent 0662c58b

drivers/scsi/libata-eh.c

+11 −12
Original line number Diff line number Diff line
@@ -190,7 +190,6 @@ enum scsi_eh_timer_return ata_scsi_timed_out(struct scsi_cmnd *cmd) 
void ata_scsi_error(struct Scsi_Host *host)

{

	struct ata_port *ap = ata_shost_to_port(host);

	spinlock_t *ap_lock = ap->lock;

	int i, repeat_cnt = ATA_EH_MAX_REPEAT;

	unsigned long flags;
@@ -217,7 +216,7 @@ void ata_scsi_error(struct Scsi_Host *host) 
		struct scsi_cmnd *scmd, *tmp;

		int nr_timedout = 0;



		spin_lock_irqsave(ap_lock, flags);

		spin_lock_irqsave(ap->lock, flags);



		list_for_each_entry_safe(scmd, tmp, &host->eh_cmd_q, eh_entry) {

			struct ata_queued_cmd *qc;
@@ -256,15 +255,15 @@ void ata_scsi_error(struct Scsi_Host *host) 
		if (nr_timedout)

			__ata_port_freeze(ap);



		spin_unlock_irqrestore(ap_lock, flags);

		spin_unlock_irqrestore(ap->lock, flags);

	} else

		spin_unlock_wait(ap_lock);

		spin_unlock_wait(ap->lock);



 repeat:

	/* invoke error handler */

	if (ap->ops->error_handler) {

		/* fetch & clear EH info */

		spin_lock_irqsave(ap_lock, flags);

		spin_lock_irqsave(ap->lock, flags);



		memset(&ap->eh_context, 0, sizeof(ap->eh_context));

		ap->eh_context.i = ap->eh_info;
@@ -273,7 +272,7 @@ void ata_scsi_error(struct Scsi_Host *host) 
		ap->pflags |= ATA_PFLAG_EH_IN_PROGRESS;

		ap->pflags &= ~ATA_PFLAG_EH_PENDING;



		spin_unlock_irqrestore(ap_lock, flags);

		spin_unlock_irqrestore(ap->lock, flags);



		/* invoke EH.  if unloading, just finish failed qcs */

		if (!(ap->pflags & ATA_PFLAG_UNLOADING))
@@ -285,14 +284,14 @@ void ata_scsi_error(struct Scsi_Host *host) 
		 * recovered the port but before this point.  Repeat

		 * EH in such case.

		 */

		spin_lock_irqsave(ap_lock, flags);

		spin_lock_irqsave(ap->lock, flags);



		if (ap->pflags & ATA_PFLAG_EH_PENDING) {

			if (--repeat_cnt) {

				ata_port_printk(ap, KERN_INFO,

					"EH pending after completion, "

					"repeating EH (cnt=%d)\n", repeat_cnt);

				spin_unlock_irqrestore(ap_lock, flags);

				spin_unlock_irqrestore(ap->lock, flags);

				goto repeat;

			}

			ata_port_printk(ap, KERN_ERR, "EH pending after %d "
@@ -302,14 +301,14 @@ void ata_scsi_error(struct Scsi_Host *host) 
		/* this run is complete, make sure EH info is clear */

		memset(&ap->eh_info, 0, sizeof(ap->eh_info));



		/* Clear host_eh_scheduled while holding ap_lock such

		/* Clear host_eh_scheduled while holding ap->lock such

		 * that if exception occurs after this point but

		 * before EH completion, SCSI midlayer will

		 * re-initiate EH.

		 */

		host->host_eh_scheduled = 0;



		spin_unlock_irqrestore(ap_lock, flags);

		spin_unlock_irqrestore(ap->lock, flags);

	} else {

		WARN_ON(ata_qc_from_tag(ap, ap->active_tag) == NULL);

		ap->ops->eng_timeout(ap);
@@ -321,7 +320,7 @@ void ata_scsi_error(struct Scsi_Host *host) 
	scsi_eh_flush_done_q(&ap->eh_done_q);



	/* clean up */

	spin_lock_irqsave(ap_lock, flags);

	spin_lock_irqsave(ap->lock, flags);



	if (ap->pflags & ATA_PFLAG_LOADING) {

		ap->pflags &= ~ATA_PFLAG_LOADING;
@@ -338,7 +337,7 @@ void ata_scsi_error(struct Scsi_Host *host) 
	ap->pflags &= ~ATA_PFLAG_EH_IN_PROGRESS;

	wake_up_all(&ap->eh_wait_q);



	spin_unlock_irqrestore(ap_lock, flags);

	spin_unlock_irqrestore(ap->lock, flags);



	DPRINTK("EXIT\n");

}

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