PM: Allow SCSI devices to suspend/resume asynchronously

Set power.async_suspend for all SCSI devices, targets and hosts, so
that they can be suspended and resumed in parallel with the main
suspend/resume thread and possibly with other devices they don't
depend on in a known way (i.e. devices which are not their parents or
children).

The power.async_suspend flag is also set for devices that don't have
suspend or resume callbacks, because otherwise they would make the
main suspend/resume thread wait for their "asynchronous" children
(during suspend) or parents (during resume), effectively negating the
possible gains from executing these devices' suspend and resume
callbacks asynchronously.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
This commit is contained in:
Rafael J. Wysocki 2010-02-08 19:18:26 +01:00
parent 927bc9165d
commit 4cb077d93a
2 changed files with 8 additions and 0 deletions

View file

@ -215,6 +215,8 @@ int scsi_add_host_with_dma(struct Scsi_Host *shost, struct device *dev,
shost->shost_gendev.parent = dev ? dev : &platform_bus;
shost->dma_dev = dma_dev;
device_enable_async_suspend(&shost->shost_gendev);
error = device_add(&shost->shost_gendev);
if (error)
goto out;
@ -222,6 +224,8 @@ int scsi_add_host_with_dma(struct Scsi_Host *shost, struct device *dev,
scsi_host_set_state(shost, SHOST_RUNNING);
get_device(shost->shost_gendev.parent);
device_enable_async_suspend(&shost->shost_dev);
error = device_add(&shost->shost_dev);
if (error)
goto out_del_gendev;

View file

@ -847,6 +847,8 @@ static int scsi_target_add(struct scsi_target *starget)
if (starget->state != STARGET_CREATED)
return 0;
device_enable_async_suspend(&starget->dev);
error = device_add(&starget->dev);
if (error) {
dev_err(&starget->dev, "target device_add failed, error %d\n", error);
@ -886,11 +888,13 @@ int scsi_sysfs_add_sdev(struct scsi_device *sdev)
return error;
transport_configure_device(&starget->dev);
device_enable_async_suspend(&sdev->sdev_gendev);
error = device_add(&sdev->sdev_gendev);
if (error) {
printk(KERN_INFO "error 1\n");
goto out_remove;
}
device_enable_async_suspend(&sdev->sdev_dev);
error = device_add(&sdev->sdev_dev);
if (error) {
printk(KERN_INFO "error 2\n");