aboutsummaryrefslogtreecommitdiffstats
path: root/include/linux
diff options
context:
space:
mode:
authorJeff Garzik <jeff@garzik.org>2010-11-16 02:10:29 -0500
committerLinus Torvalds <torvalds@linux-foundation.org>2010-11-16 13:33:23 -0800
commitf281233d3eba15fb225d21ae2e228fd4553d824a (patch)
tree51134454ba8acb558735f90be5540f7d756483e3 /include/linux
parentbdbd01ac444bffb3c9aefed3059d12554059b320 (diff)
downloadkernel_samsung_smdk4412-f281233d3eba15fb225d21ae2e228fd4553d824a.zip
kernel_samsung_smdk4412-f281233d3eba15fb225d21ae2e228fd4553d824a.tar.gz
kernel_samsung_smdk4412-f281233d3eba15fb225d21ae2e228fd4553d824a.tar.bz2
SCSI host lock push-down
Move the mid-layer's ->queuecommand() invocation from being locked with the host lock to being unlocked to facilitate speeding up the critical path for drivers who don't need this lock taken anyway. The patch below presents a simple SCSI host lock push-down as an equivalent transformation. No locking or other behavior should change with this patch. All existing bugs and locking orders are preserved. Additionally, add one parameter to queuecommand, struct Scsi_Host * and remove one parameter from queuecommand, void (*done)(struct scsi_cmnd *) Scsi_Host* is a convenient pointer that most host drivers need anyway, and 'done' is redundant to struct scsi_cmnd->scsi_done. Minimal code disturbance was attempted with this change. Most drivers needed only two one-line modifications for their host lock push-down. Signed-off-by: Jeff Garzik <jgarzik@redhat.com> Acked-by: James Bottomley <James.Bottomley@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'include/linux')
-rw-r--r--include/linux/libata.h2
1 files changed, 1 insertions, 1 deletions
diff --git a/include/linux/libata.h b/include/linux/libata.h
index 15b77b8..d947b12 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -986,7 +986,7 @@ extern void ata_host_init(struct ata_host *, struct device *,
unsigned long, struct ata_port_operations *);
extern int ata_scsi_detect(struct scsi_host_template *sht);
extern int ata_scsi_ioctl(struct scsi_device *dev, int cmd, void __user *arg);
-extern int ata_scsi_queuecmd(struct scsi_cmnd *cmd, void (*done)(struct scsi_cmnd *));
+extern int ata_scsi_queuecmd(struct Scsi_Host *h, struct scsi_cmnd *cmd);
extern int ata_sas_scsi_ioctl(struct ata_port *ap, struct scsi_device *dev,
int cmd, void __user *arg);
extern void ata_sas_port_destroy(struct ata_port *);