linux/drivers
Alexey Dobriyan a8de663916 nvme-pci: fix "slimmer CQ head update"
Pre-incrementing ->cq_head can't be done in memory because OOB value
can be observed by another context.

This devalues space savings compared to original code :-\

	$ ./scripts/bloat-o-meter ../vmlinux-000 ../obj/vmlinux
	add/remove: 0/0 grow/shrink: 0/4 up/down: 0/-32 (-32)
	Function                                     old     new   delta
	nvme_poll_irqdisable                         464     456      -8
	nvme_poll                                    455     447      -8
	nvme_irq                                     388     380      -8
	nvme_dev_disable                             955     947      -8

But the code is minimal now: one read for head, one read for q_depth,
one increment, one comparison, single instruction phase bit update and
one write for new head.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Reported-by: John Garry <john.garry@huawei.com>
Tested-by: John Garry <john.garry@huawei.com>
Fixes: e2a366a4b0 ("nvme-pci: slimmer CQ head update")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-05-09 16:07:58 -06:00
..
accessibility
acpi More ACPI updates for 5.7-rc1 2020-04-10 09:52:15 -07:00
amba Revert "amba: Initialize dma_parms for amba devices" 2020-04-01 08:03:28 +02:00
android
ata ahci: Add Intel Comet Lake PCH-U PCI ID 2020-04-16 10:26:52 -06:00
atm .gitignore: add SPDX License Identifier 2020-03-25 11:50:48 +01:00
auxdisplay
base mm/memory_hotplug: allow to specify a default online_type 2020-04-07 10:43:41 -07:00
bcma
block null_blk: Cleanup zoned device initialization 2020-04-23 09:35:09 -06:00
bluetooth
bus ARM: driver updates 2020-04-03 15:05:35 -07:00
cdrom
char Merge branch 'akpm' (patches from Andrew) 2020-04-10 17:57:48 -07:00
clk There's not much to see in the core framework this time around. Instead the 2020-04-05 10:43:32 -07:00
clocksource clocksource/drivers/timer-vf-pit: Add missing parenthesis 2020-04-05 09:24:58 +02:00
connector
counter
cpufreq Additional power management updates for 5.7-rc1 2020-04-06 10:14:39 -07:00
cpuidle Merge branch 'pm-cpuidle' 2020-04-10 11:32:22 +02:00
crypto Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2020-04-08 21:35:29 -07:00
dax dax: Move mandatory ->zero_page_range() check in alloc_dax() 2020-04-02 19:15:03 -07:00
dca
devfreq PM / devfreq: Fix handling dev_pm_qos_remove_request result 2020-03-25 08:35:03 +09:00
dio
dma drivers/dma/tegra20-apb-dma.c: fix platform_get_irq.cocci warnings 2020-04-10 15:36:22 -07:00
dma-buf A bunch of fixes to avoid null pointer dereference in fbcon, fix a return 2020-04-08 09:14:34 +10:00
edac Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2020-03-30 16:40:08 -07:00
eisa .gitignore: add SPDX License Identifier 2020-03-25 11:50:48 +01:00
extcon Char/Misc driver patches for 5.7-rc1 2020-04-03 13:22:40 -07:00
firewire
firmware efi/libstub/file: Merge file name buffers to reduce stack usage 2020-04-14 08:32:15 +02:00
fpga
fsi
gnss
gpio This is the bulk of GPIO development for the v5.7 kernel cycle. 2020-04-04 10:27:00 -07:00
gpu Kbuild updates for v5.7 (2nd) 2020-04-11 09:46:12 -07:00
greybus
hid Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/hid/hid 2020-04-01 15:18:42 -07:00
hsi
hv hyperv-fixes for 5.7-rc1 2020-04-14 11:58:04 -07:00
hwmon change email address for Pali Rohár 2020-04-10 15:36:22 -07:00
hwspinlock hwspinlock: hwspinlock_internal.h: Replace zero-length array with flexible-array member 2020-03-25 22:30:46 -07:00
hwtracing
i2c Merge branch 'i2c/for-5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux 2020-04-02 15:54:13 -07:00
i3c i3c: convert to use i2c_new_client_device() 2020-03-29 10:35:50 +02:00
ide drivers/ide: Fix build regression. 2020-04-04 18:07:59 -07:00
idle Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2020-03-30 16:40:08 -07:00
iio chrome platform changes for 5.7 2020-04-08 21:25:49 -07:00
infiniband RDMA 5.7 pull request 2020-04-01 18:18:18 -07:00
input Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input 2020-04-07 20:20:12 -07:00
interconnect
iommu Merge branches 'iommu/fixes', 'arm/qcom', 'arm/omap', 'arm/smmu', 'x86/amd', 'x86/vt-d', 'virtio' and 'core' into next 2020-03-27 11:33:27 +01:00
ipack
irqchip Two reverts addressing regressions of the Xilinx interrupt controller 2020-04-05 11:57:12 -07:00
isdn mISDN: make dmril and dmrim static 2020-04-16 13:52:31 -07:00
leds leds: core: Fix warning message when init_data 2020-04-06 23:12:08 +02:00
lightnvm for-5.7/drivers-2020-03-29 2020-03-30 11:43:51 -07:00
macintosh Char/Misc driver patches for 5.7-rc1 2020-04-03 13:22:40 -07:00
mailbox
mcb
md libnvdimm for 5.7 2020-04-08 21:03:40 -07:00
media Power management updates for 5.7-rc1 2020-03-30 15:05:01 -07:00
memory ARM: driver updates 2020-04-03 15:05:35 -07:00
memstick
message scsi: message: fusion: Replace zero-length array with flexible-array member 2020-03-26 22:40:47 -04:00
mfd mfd: intel-lpss: Fix Intel Elkhart Lake LPSS I2C input clock 2020-03-30 07:35:28 +01:00
misc virtio: fixes, vdpa 2020-04-08 10:51:53 -07:00
mmc MMC core: 2020-03-31 16:13:09 -07:00
most
mtd mtd: spi-nor: Compile files in controllers/ directory 2020-04-09 22:00:13 +02:00
mux
net Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-04-16 14:52:29 -07:00
nfc Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-03-25 18:58:11 -07:00
ntb pci-v5.7-changes 2020-04-03 14:25:02 -07:00
nubus
nvdimm libnvdimm for 5.7 2020-04-08 21:03:40 -07:00
nvme nvme-pci: fix "slimmer CQ head update" 2020-05-09 16:07:58 -06:00
nvmem nvmem: core: remove nvmem_sysfs_get_groups() 2020-03-25 19:23:49 +01:00
of of: unittest: kmemleak in duplicate property update 2020-04-17 08:31:34 -05:00
opp opp: Manage empty OPP tables with clk handle 2020-04-13 16:14:55 +05:30
oprofile
parisc parisc: Replace setup_irq() by request_irq() 2020-04-05 22:05:23 +02:00
parport
pci IOMMU Updates for Linux v5.7 2020-04-08 11:00:00 -07:00
pcmcia pcmcia: remove some unused space characters 2020-03-31 18:48:22 +02:00
perf arm64 updates for 5.7: 2020-03-31 10:05:01 -07:00
phy pci-v5.7-changes 2020-04-03 14:25:02 -07:00
pinctrl This is the bulk of GPIO development for the v5.7 kernel cycle. 2020-04-04 10:27:00 -07:00
platform chrome-platform fixes for v5.7-rc2 2020-04-16 15:00:57 -07:00
pnp
power change email address for Pali Rohár 2020-04-10 15:36:22 -07:00
powercap Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2020-03-30 16:40:08 -07:00
pps
ps3 powerpc/ps3: Remove an unneeded NULL check 2020-04-03 00:09:59 +11:00
ptp ptp: Avoid deadlocks in the programmable pin code. 2020-03-30 11:16:38 -07:00
pwm pwm: pca9685: Fix PWM/GPIO inter-operation 2020-04-03 21:41:42 +02:00
rapidio
ras
regulator spi/regulator: Updates for v5.7 2020-03-30 14:58:26 -07:00
remoteproc remoteproc/omap: Fix set_load call in omap_rproc_request_timer 2020-04-03 10:47:21 -07:00
reset
rpmsg
rtc - New Drivers 2020-04-07 19:48:52 -07:00
s390 s390/dasd: remove IOSCHED_DEADLINE from DASD Kconfig 2020-04-17 08:05:27 -06:00
sbus
scsi SCSI misc on 20200410 2020-04-10 12:21:11 -07:00
sfi
sh
siox
slimbus
soc RISC-V Patches for the 5.7 Merge Window, Part 1 2020-04-09 10:51:30 -07:00
soundwire Char/Misc driver patches for 5.7-rc1 2020-04-03 13:22:40 -07:00
spi sound updates for 5.7-rc1 2020-04-02 15:50:04 -07:00
spmi
ssb
staging mm/vma: introduce VM_ACCESS_FLAGS 2020-04-10 15:36:21 -07:00
target SCSI misc on 20200410 2020-04-10 12:21:11 -07:00
tc
tee ARM: driver updates 2020-04-03 15:05:35 -07:00
thermal - Convert tsens configuration DT binding to yaml (Rajeshwari) 2020-04-07 20:00:16 -07:00
thunderbolt
tty powerpc updates for 5.7 2020-04-05 11:12:59 -07:00
uio
usb SCSI misc on 20200402 2020-04-02 17:03:53 -07:00
vdpa vdpa: move to drivers/vdpa 2020-04-02 10:41:40 -04:00
vfio vfio: Ignore -ENODEV when getting MSI cookie 2020-04-01 13:51:51 -06:00
vhost vhost: introduce vDPA-based backend 2020-04-02 10:41:40 -04:00
video drm fixes for 5.7-rc1 2020-04-07 20:24:34 -07:00
virt
virtio virtio: fixes, vdpa 2020-04-08 10:51:53 -07:00
visorbus
vlynq
vme
w1
watchdog watchdog: sp805: fix restart handler 2020-04-08 11:18:38 +02:00
xen xen: branch for v5.7-rc2 2020-04-17 10:35:17 -07:00
zorro SPDX patches for 5.7-rc1. 2020-04-03 13:12:26 -07:00
Kconfig virtio: fixes, vdpa 2020-04-08 10:51:53 -07:00
Makefile virtio: fixes, vdpa 2020-04-08 10:51:53 -07:00