Jens Axboe 9937a5e2f3 scsi: remove performance regression due to async queue run ... Commit c21e6beb removed our queue request_fn re-enter protection, and defaulted to always running the queues from kblockd to be safe. This was a known potential slow down, but should be safe. Unfortunately this is causing big performance regressions for some, so we need to improve this logic. Looking into the details of the re-enter, the real issue is on requeue of requests. Requeue of requests upon seeing a BUSY condition from the device ends up re-running the queue, causing traces like this: scsi_request_fn() scsi_dispatch_cmd() scsi_queue_insert() __scsi_queue_insert() scsi_run_queue() scsi_request_fn() ... potentially causing the issue we want to avoid. So special case the requeue re-run of the queue, but improve it to offload the entire run of local queue and starved queue from a single workqueue callback. This is a lot better than potentially kicking off a workqueue run for each device seen. This also fixes the issue of the local device going into recursion, since the above mentioned commit never moved that queue run out of line. Signed-off-by: Jens Axboe <jaxboe@fusionio.com>		2011-05-17 11:04:44 +02:00
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fc	Fix common misspellings	2011-03-31 11:26:23 -03:00
fc_encode.h	[SCSI] libfc: introduce __fc_fill_fc_hdr that accepts fc_hdr as an argument	2011-02-28 18:32:33 -06:00
fc_frame.h
iscsi_if.h	Fix common misspellings	2011-03-31 11:26:23 -03:00
iscsi_proto.h
Kbuild
libfc.h	Fix common misspellings	2011-03-31 11:26:23 -03:00
libfcoe.h	[SCSI] libfcoe: Move FCOE_MTU definition from fcoe.h to libfcoe.h	2011-02-28 18:33:12 -06:00
libiscsi.h	[SCSI] cxgbi: convert to use iscsi_conn_get_addr_param	2011-02-24 12:41:15 -05:00
libiscsi_tcp.h	Fix common misspellings	2011-03-31 11:26:23 -03:00
libsas.h
libsrp.h
osd_attributes.h
osd_initiator.h	Fix common misspellings	2011-03-31 11:26:23 -03:00
osd_protocol.h
osd_sec.h
osd_sense.h
osd_types.h
sas.h
sas_ata.h	libsas: convert to libata new error handler	2011-03-02 02:36:45 -05:00
scsi.h	Merge git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6	2011-03-17 17:54:40 -07:00
scsi_bsg_fc.h
scsi_cmnd.h
scsi_dbg.h
scsi_device.h	scsi: remove performance regression due to async queue run	2011-05-17 11:04:44 +02:00
scsi_devinfo.h
scsi_dh.h
scsi_driver.h
scsi_eh.h
scsi_host.h	Fix common misspellings	2011-03-31 11:26:23 -03:00
scsi_ioctl.h
scsi_netlink.h
scsi_netlink_fc.h
scsi_scan.h
scsi_tcq.h
scsi_tgt.h
scsi_tgt_if.h
scsi_transport.h
scsi_transport_fc.h	Fix common misspellings	2011-03-31 11:26:23 -03:00
scsi_transport_iscsi.h	[SCSI] iscsi class: add callout to get iscsi_endpoint values	2011-02-24 12:41:12 -05:00
scsi_transport_sas.h
scsi_transport_spi.h
scsi_transport_srp.h
scsicam.h
sg.h
srp.h