OpenE2K
/
linux
6
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity
linux/drivers/scsi
History
Paolo Bonzini 9141a4ca0d virtio-scsi: introduce multiqueue support 
This patch adds queue steering to virtio-scsi.  When a target is sent
multiple requests, we always drive them to the same queue so that FIFO
processing order is kept.  However, if a target was idle, we can choose
a queue arbitrarily.  In this case the queue is chosen according to the
current VCPU, so the driver expects the number of request queues to be
equal to the number of VCPUs.  This makes it easy and fast to select
the queue, and also lets the driver optimize the IRQ affinity for the
virtqueues (each virtqueue's affinity is set to the CPU that "owns"
the queue).

The speedup comes from improving cache locality and giving CPU affinity
to the virtqueues, which is why this scheme was selected.  Assuming that
the thread that is sending requests to the device is I/O-bound, it is
likely to be sleeping at the time the ISR is executed, and thus executing
the ISR on the same processor that sent the requests is cheap.

However, the kernel will not execute the ISR on the "best" processor
unless you explicitly set the affinity.  This is because in practice
you will have many such I/O-bound processes and thus many otherwise
idle processors.  Then the kernel will execute the ISR on a random
processor, rather than the one that is sending requests to the device.

The alternative to per-CPU virtqueues is per-target virtqueues.  To
achieve the same locality, we could dynamically choose the virtqueue's
affinity based on the CPU of the last task that sent a request.  This
is less appealing because we do not set the affinity directly---we only
provide a hint to the irqbalanced running in userspace.  Dynamically
changing the affinity only works if the userspace applies the hint
fast enough.

Cc: linux-scsi@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Wanlong Gao <gaowanlong@cn.fujitsu.com>
Reviewed-by: Asias He <asias@redhat.com>
Tested-by: Venkatesh Srinivas <venkateshs@google.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
 		2013-04-08 23:06:55 +09:30
..
aacraid [SCSI] aacraid: suppress two GCC warnings 2013-02-24 09:38:10 +00:00
aic7xxx scsi: fix various printk and comment typos 2012-09-01 08:24:35 -07:00
aic7xxx_old Fix common misspellings 2011-03-31 11:26:23 -03:00
aic94xx Drivers: scsi: remove __dev* attributes. 2013-01-03 15:57:01 -08:00
arcmsr workqueue: deprecate flush[_delayed]_work_sync() 2012-08-20 14:51:24 -07:00
arm drivers/scsi/arm: remove depends on CONFIG_EXPERIMENTAL 2013-01-21 14:52:45 -08:00
be2iscsi Drivers: scsi: remove __dev* attributes. 2013-01-03 15:57:01 -08:00
bfa SCSI misc on 20130222 2013-02-28 12:43:43 -08:00
bnx2fc FCoE Updates for 3.9 2013-03-01 09:10:08 +00:00
bnx2i [SCSI] bnx2i: fix the bit manipulation when setting the error mask 2013-01-29 14:15:34 +11:00
csiostor SCSI misc on 20130222 2013-02-28 12:43:43 -08:00
cxgbi [SCSI] cxgb4i: Remove the scsi host device when removing device 2013-01-30 11:58:06 +11:00
device_handler drivers/scsi/device_handler: remove depends on CONFIG_EXPERIMENTAL 2013-01-21 14:52:45 -08:00
dpt atomic: use <linux/atomic.h> 2011-07-26 16:49:47 -07:00
fcoe FCoE Updates for 3.9 2013-03-01 09:10:08 +00:00
fnic [SCSI] fnic: Fnic Trace Utility 2013-02-22 17:32:07 +00:00
ibmvscsi Drivers: scsi: remove __dev* attributes. 2013-01-03 15:57:01 -08:00
isci efi: Make 'efi_enabled' a function to query EFI facilities 2013-01-30 11:51:59 -08:00
libfc libfc: XenServer fails to mount root filesystem. 2013-02-15 09:33:27 -08:00
libsas treewide: fix typo of "suport" in various comments and Kconfig 2012-11-19 14:16:09 +01:00
lpfc SCSI for-linus on 20130301 2013-03-02 11:42:16 -08:00
megaraid [SCSI] megaraid_sas: Version and Changelog update 2013-02-22 15:37:15 +00:00
mpt2sas [SCSI] mpt2sas: Add support for OEM specific controller 2013-02-24 08:48:15 +00:00
mpt3sas [SCSI] mpt3sas: remove unused variables 2013-01-29 14:15:35 +11:00
mvsas [SCSI] mvsas: fixed timeout issue when removing module 2013-02-22 11:18:33 +00:00
osd SCSI for-linus on 20130301 2013-03-02 11:42:16 -08:00
pcmcia module_param: make bool parameters really bool (drivers & misc) 2012-01-13 09:32:20 +10:30
pm8001 [SCSI] pm80xx: fix for memory region free 2013-02-22 15:44:40 +00:00
qla2xxx [SCSI] qla2xxx: Wait for IDC complete event to finish loopback operation. 2013-02-22 15:06:24 +00:00
qla4xxx [SCSI] qla4xxx: don't free NULL dma pool 2013-02-22 11:24:22 +00:00
sym53c8xx_2 Drivers: scsi: remove __dev* attributes. 2013-01-03 15:57:01 -08:00
ufs [SCSI] ufs: Separate PCI code into glue driver 2013-02-25 16:56:32 +00:00
.gitignore
…
3w-9xxx.c new helper: file_inode(file) 2013-02-22 23:31:31 -05:00
3w-9xxx.h Fix common misspellings 2011-03-31 11:26:23 -03:00
3w-sas.c new helper: file_inode(file) 2013-02-22 23:31:31 -05:00
3w-sas.h
…
3w-xxxx.c new helper: file_inode(file) 2013-02-22 23:31:31 -05:00
3w-xxxx.h Fix common misspellings 2011-03-31 11:26:23 -03:00
53c700.c Remove all #inclusions of asm/system.h 2012-03-28 18:30:03 +01:00
53c700.h
…
53c700.scr Fix common misspellings 2011-03-31 11:26:23 -03:00
53c700_d.h_shipped Fix common misspellings 2011-03-31 11:26:23 -03:00
BusLogic.c Drivers: scsi: remove __dev* attributes. 2013-01-03 15:57:01 -08:00
BusLogic.h
…
FlashPoint.c Fix common misspellings 2011-03-31 11:26:23 -03:00
Kconfig Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2013-02-21 17:40:58 -08:00
Makefile [SCSI] mpt3sas: add new driver supporting 12GB SAS 2012-12-01 10:09:17 +00:00
NCR53c406a.c
…
NCR5380.c Drivers: scsi: remove __dev* attributes. 2013-01-03 15:57:01 -08:00
NCR5380.h
…
NCR_D700.c Drivers: scsi: remove __dev* attributes. 2013-01-03 15:57:01 -08:00
NCR_D700.h
…
NCR_Q720.c Drivers: scsi: remove __dev* attributes. 2013-01-03 15:57:01 -08:00
NCR_Q720.h
…
a100u2w.c Drivers: scsi: remove __dev* attributes. 2013-01-03 15:57:01 -08:00
a100u2w.h
…
a2091.c Drivers: scsi: remove __dev* attributes. 2013-01-03 15:57:01 -08:00
a2091.h
…
a3000.c scsi: Fix up files implicitly depending on module.h inclusion 2011-10-31 19:31:24 -04:00
a3000.h
…
a4000t.c
…
advansys.c Drivers: scsi: remove __dev* attributes. 2013-01-03 15:57:01 -08:00
aha152x.c Drivers: scsi: remove __dev* attributes. 2013-01-03 15:57:01 -08:00
aha152x.h
…
aha1542.c treewide: Put a space between #include and FILE 2012-06-28 11:44:36 +02:00
aha1542.h
…
aha1740.c Drivers: scsi: remove __dev* attributes. 2013-01-03 15:57:01 -08:00
aha1740.h
…
aic7xxx_old.c Fix common misspellings 2011-03-31 11:26:23 -03:00
atari_NCR5380.c [SCSI] atari_NCR5380: Provide a dummy NCR5380_exit() 2011-06-29 15:11:21 -05:00
atari_scsi.c scsi/atari: Make more functions static 2012-04-22 20:16:49 +02:00
atari_scsi.h scsi/atari: Make more functions static 2012-04-22 20:16:49 +02:00
atp870u.c Drivers: scsi: remove __dev* attributes. 2013-01-03 15:57:01 -08:00
atp870u.h
…
bvme6000_scsi.c Drivers: scsi: remove __dev* attributes. 2013-01-03 15:57:01 -08:00
ch.c scsi: convert to idr_alloc() 2013-02-27 19:10:18 -08:00
constants.c [SCSI] add DID_TARGET_FAILURE and DID_NEXUS_FAILURE to hostbyte_table in constants.c 2012-09-14 11:58:53 +01:00
dc395x.c [SCSI] dc395x: uninitialized variable in device_alloc() 2013-02-24 09:29:34 +00:00
dc395x.h Fix common misspellings 2011-03-31 11:26:23 -03:00
dmx3191d.c Drivers: scsi: remove __dev* attributes. 2013-01-03 15:57:01 -08:00
dpt_i2o.c new helper: file_inode(file) 2013-02-22 23:31:31 -05:00
dpti.h
…
dtc.c Remove all #inclusions of asm/system.h 2012-03-28 18:30:03 +01:00
dtc.h
…
eata.c [SCSI] remove cmd->serial_number litter 2011-05-01 10:22:40 -05:00
eata_generic.h
…
eata_pio.c [SCSI] remove cmd->serial_number litter 2011-05-01 10:22:40 -05:00
eata_pio.h
…
esp_scsi.c scsi: Use vsprintf extention %pf with builtin_return_address 2012-04-05 17:09:40 -07:00
esp_scsi.h
…
fdomain.c Drivers: scsi: remove __dev* attributes. 2013-01-03 15:57:01 -08:00
fdomain.h
…
g_NCR5380.c Drivers: scsi: remove __dev* attributes. 2013-01-03 15:57:01 -08:00
g_NCR5380.h
…
g_NCR5380_mmio.c
…
gdth.c [SCSI] gdth: Remove buggy ROM handling 2013-01-29 13:55:06 +11:00
gdth.h gdt: remove unnecessary #defines 2012-09-01 08:43:34 -07:00
gdth_ioctl.h
…
gdth_proc.c
…
gdth_proc.h
…
gvp11.c Drivers: scsi: remove __dev* attributes. 2013-01-03 15:57:01 -08:00
gvp11.h
…
hosts.c driver-core: constify data for class_find_device() 2013-02-06 12:18:56 -08:00
hpsa.c [SCSI] hpsa: check for dma_mapping_error in hpsa_passthru ioctls 2013-02-24 09:36:58 +00:00
hpsa.h [SCSI] hpsa: dial down lockup detection during firmware flash 2012-05-10 09:19:39 +01:00
hpsa_cmd.h [SCSI] hpsa: dial down lockup detection during firmware flash 2012-05-10 09:19:39 +01:00
hptiop.c Drivers: scsi: remove __dev* attributes. 2013-01-03 15:57:01 -08:00
hptiop.h [SCSI] hptiop: Support HighPoint RR4520/RR4522 HBA 2012-11-27 08:59:43 +04:00
imm.c Fix common misspellings 2011-03-31 11:26:23 -03:00
imm.h
…
in2000.c Remove all #inclusions of asm/system.h 2012-03-28 18:30:03 +01:00
in2000.h
…
initio.c Drivers: scsi: remove __dev* attributes. 2013-01-03 15:57:01 -08:00
initio.h Fix common misspellings 2011-03-31 11:26:23 -03:00
ipr.c [SCSI] ipr: Fix oops while resetting an ipr adapter 2013-02-24 08:24:48 +00:00
ipr.h [SCSI] ipr: Fix oops while resetting an ipr adapter 2013-02-24 08:24:48 +00:00
ips.c Drivers: scsi: remove __dev* attributes. 2013-01-03 15:57:01 -08:00
ips.h Fix common misspellings 2011-03-31 11:26:23 -03:00
iscsi_boot_sysfs.c switch ->is_visible() to returning umode_t 2012-01-03 22:54:55 -05:00
iscsi_tcp.c [SCSI] iscsi_tcp: increase max_lun to ~0, don't care 2012-09-24 12:10:55 +04:00
iscsi_tcp.h [SCSI] iscsi_tcp: use iscsi_conn_get_addr_param libiscsi function 2011-02-24 12:41:10 -05:00
jazz_esp.c Drivers: scsi: remove __dev* attributes. 2013-01-03 15:57:01 -08:00
lasi700.c Drivers: scsi: remove __dev* attributes. 2013-01-03 15:57:01 -08:00
libiscsi.c [SCSI] libiscsi: fix cmd timeout/completion race 2012-02-19 08:09:00 -06:00
libiscsi_tcp.c SCSI updates on 20120319 2012-03-22 12:55:29 -07:00
libsrp.c scsi: Fix up files implicitly depending on module.h inclusion 2011-10-31 19:31:24 -04:00
mac53c94.c Remove all #inclusions of asm/system.h 2012-03-28 18:30:03 +01:00
mac53c94.h
…
mac_esp.c Drivers: scsi: remove __dev* attributes. 2013-01-03 15:57:01 -08:00
mac_scsi.c Remove all #inclusions of asm/system.h 2012-03-28 18:30:03 +01:00
mac_scsi.h
…
megaraid.c Drivers: scsi: remove __dev* attributes. 2013-01-03 15:57:01 -08:00
megaraid.h megaraid: remove unnecessary #defines 2012-09-01 08:42:43 -07:00
mesh.c Remove all #inclusions of asm/system.h 2012-03-28 18:30:03 +01:00
mesh.h
…
mvme16x_scsi.c Drivers: scsi: remove __dev* attributes. 2013-01-03 15:57:01 -08:00
mvme147.c
…
mvme147.h
…
mvumi.c Drivers: scsi: remove __dev* attributes. 2013-01-03 15:57:01 -08:00
mvumi.h [SCSI] mvumi: Add support for Marvell SAS/SATA RAID-on-Chip(ROC) 88RC9580 2012-10-07 11:34:36 +01:00
ncr53c8xx.c Remove all #inclusions of asm/system.h 2012-03-28 18:30:03 +01:00
ncr53c8xx.h
…
nsp32.c Drivers: scsi: remove __dev* attributes. 2013-01-03 15:57:01 -08:00
nsp32.h Fix common misspellings 2011-03-31 11:26:23 -03:00
nsp32_debug.c treewide: fix a few typos in comments 2011-05-10 10:16:21 +02:00
nsp32_io.h
…
osst.c Remove all #inclusions of asm/system.h 2012-03-28 18:30:03 +01:00
osst.h Fix common misspellings 2011-03-31 11:26:23 -03:00
osst_detect.h
…
osst_options.h
…
pas16.c Remove all #inclusions of asm/system.h 2012-03-28 18:30:03 +01:00
pas16.h
…
pmcraid.c Drivers: scsi: remove __dev* attributes. 2013-01-03 15:57:01 -08:00
pmcraid.h scsi: Fix typo in pmcraid.h 2012-02-21 11:40:37 +01:00
ppa.c
…
ppa.h
…
ps3rom.c Drivers: scsi: remove __dev* attributes. 2013-01-03 15:57:01 -08:00
qla1280.c Drivers: scsi: remove __dev* attributes. 2013-01-03 15:57:01 -08:00
qla1280.h
…
qlogicfas.c Drivers: scsi: remove __dev* attributes. 2013-01-03 15:57:01 -08:00
qlogicfas408.c
…
qlogicfas408.h
…
qlogicpti.c Drivers: scsi: remove __dev* attributes. 2013-01-03 15:57:01 -08:00
qlogicpti.h
…
raid_class.c
…
script_asm.pl
…
scsi.c [SCSI] Add a report opcode helper 2012-11-13 21:11:31 -08:00
scsi.h
…
scsi_debug.c [SCSI] scsi_debug: Fix off-by-one bug when unmapping region 2012-10-09 12:23:11 +01:00
scsi_devinfo.c [SCSI] Disable DIF on Hitachi Ultrastar 15K300 2012-09-24 12:11:00 +04:00
scsi_error.c [SCSI] Shorten the path length of scsi_cmd_to_driver() 2012-10-09 12:04:42 +01:00
scsi_ioctl.c
…
scsi_lib.c [libata] scsi: no poll when ODD is powered off 2013-01-25 15:36:43 -05:00
scsi_lib_dma.c scsi: Add export.h for EXPORT_SYMBOL/THIS_MODULE as required 2011-10-31 19:31:23 -04:00
scsi_logging.h
…
scsi_module.c
…
scsi_netlink.c scsi_netlink: Remove dead and buggy code 2012-09-13 16:26:39 -04:00
scsi_pm.c [SCSI] scsi_pm: use callbacks from dev_pm_ops for scsi devices 2012-11-30 09:26:48 +00:00
scsi_priv.h [SCSI] async: introduce 'async_domain' type 2012-07-20 09:05:54 +01:00
scsi_proc.c scsi: fix scsi_proc new kernel-doc warning 2011-05-28 23:12:11 -07:00
scsi_sas_internal.h
…
scsi_scan.c Merge SCSI misc branch into isci-for-3.6 tag 2012-10-02 08:55:12 +01:00
scsi_sysctl.c
…
scsi_sysfs.c [SCSI] prevent stack buffer overflow in host_reset 2012-11-30 09:08:16 +00:00
scsi_tgt_if.c scsi: Add export.h for EXPORT_SYMBOL/THIS_MODULE as required 2011-10-31 19:31:23 -04:00
scsi_tgt_lib.c [SCSI] esp, scsi_tgt_lib, fcoe: use list_move() instead of list_del()/list_add() combination 2011-05-01 10:20:10 -05:00
scsi_tgt_priv.h
…
scsi_trace.c [SCSI] scsi_trace: Decode UNMAP bit in WRITE SAME(10) 2011-05-24 12:38:36 -04:00
scsi_transport_api.h
…
scsi_transport_fc.c Merge branch 'for-3.6/core' of git://git.kernel.dk/linux-block 2012-08-01 09:02:41 -07:00
scsi_transport_fc_internal.h
…
scsi_transport_iscsi.c SCSI misc on 20130222 2013-02-28 12:43:43 -08:00
scsi_transport_sas.c [SCSI] scsi_transport_sas: add 12GB definitions for mpt3sas 2012-12-01 10:08:41 +00:00
scsi_transport_spi.c [SCSI] scsi_transport_spi: fix for unbalanced reference counting 2012-05-10 09:06:12 +01:00
scsi_transport_srp.c IB/srp: Allow SRP disconnect through sysfs 2012-11-30 17:40:33 -08:00
scsi_transport_srp_internal.h
…
scsi_typedefs.h
…
scsicam.c fs: move code out of buffer.c 2012-01-03 22:54:07 -05:00
sd.c [SCSI] sd: update sd to use the new pm callbacks 2012-11-30 09:28:34 +00:00
sd.h [SCSI] sd: Implement support for WRITE SAME 2012-11-13 22:45:42 -08:00
sd_dif.c [SCSI] sd: Avoid remapping bad reference tags 2012-09-24 12:10:59 +04:00
ses.c [SCSI] ses: requesting a fault indication 2011-06-29 12:14:25 -05:00
sg.c scsi: convert to idr_alloc() 2013-02-27 19:10:18 -08:00
sgiwd93.c Drivers: scsi: remove __dev* attributes. 2013-01-03 15:57:01 -08:00
sim710.c Drivers: scsi: remove __dev* attributes. 2013-01-03 15:57:01 -08:00
sni_53c710.c Drivers: scsi: remove __dev* attributes. 2013-01-03 15:57:01 -08:00
sr.c [libata] scsi: no poll when ODD is powered off 2013-01-25 15:36:43 -05:00
sr.h [SCSI] sr: check_events() ignore GET_EVENT when TUR says otherwise 2011-07-21 14:15:58 -07:00
sr_ioctl.c scsi: Fix up files implicitly depending on module.h inclusion 2011-10-31 19:31:24 -04:00
sr_vendor.c
…
st.c scsi: convert to idr_alloc() 2013-02-27 19:10:18 -08:00
st.h [SCSI] st: raise device limit 2012-09-14 17:59:29 +01:00
st_options.h
…
stex.c Drivers: scsi: remove __dev* attributes. 2013-01-03 15:57:01 -08:00
storvsc_drv.c SCSI for-linus on 20130301 2013-03-02 11:42:16 -08:00
sun3_NCR5380.c [SCSI] sun3: Remove commented out merge_contiguous_buffers 2011-06-29 15:15:05 -05:00
sun3_scsi.c Remove all #inclusions of asm/system.h 2012-03-28 18:30:03 +01:00
sun3_scsi.h
…
sun3_scsi_vme.c Remove all #inclusions of asm/system.h 2012-03-28 18:30:03 +01:00
sun3x_esp.c Drivers: scsi: remove __dev* attributes. 2013-01-03 15:57:01 -08:00
sun_esp.c Drivers: scsi: remove __dev* attributes. 2013-01-03 15:57:01 -08:00
sym53c416.c Drivers: scsi: remove __dev* attributes. 2013-01-03 15:57:01 -08:00
sym53c416.h
…
t128.c Remove all #inclusions of asm/system.h 2012-03-28 18:30:03 +01:00
t128.h
…
tmscsim.c Drivers: scsi: remove __dev* attributes. 2013-01-03 15:57:01 -08:00
tmscsim.h
…
u14-34f.c Remove all #inclusions of asm/system.h 2012-03-28 18:30:03 +01:00
ultrastor.c Remove all #inclusions of asm/system.h 2012-03-28 18:30:03 +01:00
ultrastor.h
…
virtio_scsi.c virtio-scsi: introduce multiqueue support 2013-04-08 23:06:55 +09:30
vmw_pvscsi.c Drivers: scsi: remove __dev* attributes. 2013-01-03 15:57:01 -08:00
vmw_pvscsi.h [SCSI] vmw_pvscsi: Try setting host->max_id as suggested by the device. 2012-03-27 08:26:36 +01:00
wd33c93.c Merge branch 'trivial' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6 2011-05-26 13:19:00 -07:00
wd33c93.h
…
wd7000.c Remove all #inclusions of asm/system.h 2012-03-28 18:30:03 +01:00
zalon.c Drivers: scsi: remove __dev* attributes. 2013-01-03 15:57:01 -08:00
zorro7xx.c Drivers: scsi: remove __dev* attributes. 2013-01-03 15:57:01 -08:00