Changes since v5: * Per Tejun, fixed up the naming of the ata_port helper routines * Cleaned up the return value of ata_port_pm helper routines to be 'void' * Per Tejun, added a check of whether async scanning is disabled to gate whether async resume will be performed out of caution for systems that do not handle staggered spin-up outside of the kernel. Clarified this in the changelog and added commentary in the code. === It is not everyday that a kernel operation gets > 2x faster! Great find by Todd and his AnalyzeSuspend tool [1]. Todd is on vacation so I am taking care of these patches to make sure they get in the queue for 3.15. The significant changes from Todd's last submission [2]: 1/ Split out the pure cleanup into its own patch, and expand it to clean up libsas as well 2/ Move the entirety of scsi_device resume to an async context. As written, v4 of the patchset overlapped the scsi-start-stop command with the scsi_device_resume(). Now in v5 the queue restart is properly ordered with the completion of the scsi-start-stop command. Resume completion time as reported by: "echo devices > /sys/power/pm_test && echo mem > /sys/power/state" BEFORE: PM: resume of devices complete after 2271.097 msecs AFTER: PM: resume of devices complete after 1057.404 msecs On a system with two SSDs attached via AHCI. [1]: Todd's testing showing up to 12x resume latency improvement in some cases: https://01.org/suspendresume/blogs/tebrandt/2013/hard-disk-resume-optimization-simpler-approach [2]: Todd's v4 patchset: [PATCH v4 0/2] http://marc.info/?l=linux-ide&m=138984698103487&w=2 [PATCH v4 1/2] http://marc.info/?l=linux-ide&m=138984713203515&w=2 [PATCH v4 2/2] http://marc.info/?l=linux-ide&m=138984722003539&w=2 --- Dan Williams (2): libata, libsas: kill pm_result and related cleanup scsi: async sd resume Todd Brandt (1): libata: async resume drivers/ata/libata-core.c | 135 ++++++++++++++++++----------------------- drivers/ata/libata-eh.c | 13 +--- drivers/scsi/Kconfig | 3 + drivers/scsi/libsas/sas_ata.c | 35 ++--------- drivers/scsi/scsi.c | 3 + drivers/scsi/scsi_pm.c | 128 ++++++++++++++++++++++++++++++--------- drivers/scsi/scsi_priv.h | 2 + drivers/scsi/scsi_scan.c | 2 - drivers/scsi/sd.c | 1 include/linux/libata.h | 11 +-- include/scsi/libsas.h | 1 11 files changed, 180 insertions(+), 154 deletions(-) -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html