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Tina Ruchandani 85cf955df8 aoe: use ktime_t instead of timeval
'struct frame' uses two variables to store the sent timestamp - 'struct
timeval' and jiffies. jiffies is used to avoid discrepancies caused by
updates to system time. 'struct timeval' is deprecated because it uses
32-bit representation for seconds which will overflow in year 2038.

This patch does the following:
- Replace the use of 'struct timeval' and jiffies with ktime_t, which
  is the recommended type for timestamping
- ktime_t provides both long range (like jiffies) and high resolution
  (like timeval). Using ktime_get (monotonic time) instead of wall-clock
  time prevents any discprepancies caused by updates to system time.

[updates by Arnd below]
The original patch from Tina never went anywhere as we discussed how
to keep the impact on performance minimal. I've started over now but
arrived at basically the same patch that she had originally, except for
an slightly improved tsince_hr() function. I'm making it more robust
against overflows, and also optimize explicitly for the common case
in which a frame is less than 4.2 seconds old, using only a 32-bit
division in that case.

This should make the new version more efficient than the old code,
since we replace the existing two 32-bit division in do_gettimeofday()
plus one multiplication with a single single 32-bit division in
tsince_hr() and drop the double bookkeeping. It's also more efficient
than the ktime_get_us() API we discussed before, since that would
also rely on multiple divisions.

Link: https://lists.linaro.org/pipermail/y2038/2015-May/000276.html
Signed-off-by: Tina Ruchandani <ruchandani.tina@gmail.com>
Cc: Ed Cashin <ed.cashin@acm.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-01-17 08:41:07 -07:00
..
accessibility License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
acpi PM / sleep: Avoid excess pm_runtime_enable() calls in device_resume() 2017-12-11 14:32:56 +01:00
amba A couple of dma-mapping updates: 2017-11-14 16:54:12 -08:00
android ANDROID: binder: fix transaction leak. 2017-11-28 16:54:45 +01:00
ata libata: sata_down_spd_limit should return if driver has not recorded sstatus speed 2017-12-04 13:57:03 -08:00
atm Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-11-29 13:10:25 -08:00
auxdisplay auxdisplay: img-ascii-lcd: Only build on archs that have IOMEM 2017-11-27 12:36:45 -08:00
base PM / sleep: Avoid excess pm_runtime_enable() calls in device_resume() 2017-12-11 14:32:56 +01:00
bcma Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2017-11-15 11:56:19 -08:00
block aoe: use ktime_t instead of timeval 2018-01-17 08:41:07 -07:00
bluetooth Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-11-04 09:26:51 +09:00
bus bus: arm-ccn: fix module unloading Error: Removing state 147 which has instances left. 2017-12-04 17:15:20 +00:00
cdrom Merge branch 'for-4.15/block' of git://git.kernel.dk/linux-block 2017-11-14 15:32:19 -08:00
char The big changes for IPMI that just went in had a few problems. These 2017-12-11 17:01:59 -08:00
clk We have two changes to the core framework this time around. The first being a 2017-11-17 20:04:24 -08:00
clocksource - final batch of "non trivial" timer conversions (multi-tree dependencies, 2017-11-23 16:29:05 +01:00
connector
cpufreq cpufreq: mediatek: add missing MODULE_DESCRIPTION/AUTHOR/LICENSE 2017-11-22 00:00:14 +01:00
cpuidle powerpc updates for 4.15 2017-11-16 12:47:46 -08:00
crypto powerpc updates for 4.15 2017-11-16 12:47:46 -08:00
dax device-dax: implement ->split() to catch invalid munmap attempts 2017-11-29 18:40:42 -08:00
dca
devfreq Merge branches 'pm-devfreq' and 'pm-tools' 2017-11-13 01:41:39 +01:00
dio License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
dma dmaengine: fsl-edma: disable clks on all error paths 2017-12-15 09:53:04 +05:30
dma-buf Tracing updates for 4.15: 2017-11-17 14:58:01 -08:00
edac Modules updates for v4.15 2017-11-15 13:46:33 -08:00
eisa License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
extcon USB/PHY patches for 4.15-rc1 2017-11-13 21:14:07 -08:00
firewire Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-11-13 17:56:58 -08:00
firmware ARM: SoC fixes for 4.15-rc 2017-12-10 08:26:59 -08:00
fmc License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
fpga Char/Misc patches for 4.15-rc1 2017-11-16 09:10:59 -08:00
fsi
gpio gpio: pca953x: fix vendor prefix for PCA9654 2017-12-02 22:41:43 +01:00
gpu Merge branch 'akpm' (patches from Andrew) 2017-12-14 16:35:20 -08:00
hid treewide: setup_timer() -> timer_setup() 2017-11-21 15:57:07 -08:00
hsi HSI changes for the v4.15 series 2017-11-15 13:35:43 -08:00
hv Drivers: hv: vmbus: Fix a rescind issue 2017-11-28 16:56:26 +01:00
hwmon hwmon: (jc42) optionally try to disable the SMBUS timeout 2017-11-30 13:12:44 -08:00
hwspinlock hwspinlock update for v4.15 2017-11-17 20:16:20 -08:00
hwtracing tracing: Pass export pointer as argument to ->write() 2017-12-04 07:14:30 -05:00
i2c i2c: piix4: Fix port number check on release 2017-12-12 23:27:04 +01:00
ide Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/ide 2017-11-19 08:04:41 -10:00
idle Merge branch 'pm-cpuidle' 2017-11-13 01:34:14 +01:00
iio iio: health: max30102: Temperature should be in milli Celsius 2017-12-02 11:15:14 +00:00
infiniband Second pull request for 4.15-rc 2017-12-16 13:43:08 -08:00
input treewide: Remove TIMER_FUNC_TYPE and TIMER_DATA_TYPE casts 2017-11-21 16:35:54 -08:00
iommu IOMMU fixes for Linux v4.15-rc3 2017-12-06 10:53:02 -08:00
ipack
irqchip Merge branch 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-11-26 14:39:20 -08:00
isdn treewide: setup_timer() -> timer_setup() (2 field) 2017-11-21 15:57:09 -08:00
leds LED updates for 4.15rc1 2017-11-14 18:09:31 -08:00
lightnvm lightnvm: pblk: refactor pblk_ppa_comp function 2018-01-05 08:50:12 -07:00
macintosh Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-11-13 17:56:58 -08:00
mailbox Change to POLL api and fixes for FlexRM and OMAP driver 2017-11-15 13:39:18 -08:00
mcb License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
md dm: fix incomplete request_queue initialization 2018-01-15 08:54:32 -07:00
media media fixes for v4.15-rc3 2017-12-08 13:18:47 -08:00
memory ARM: SoC driver updates for v4.15 2017-11-16 16:05:01 -08:00
memstick treewide: setup_timer() -> timer_setup() 2017-11-21 15:57:07 -08:00
message Modules updates for v4.15 2017-11-15 13:46:33 -08:00
mfd treewide: setup_timer() -> timer_setup() 2017-11-21 15:57:07 -08:00
misc Merge branch 'WIP.x86-pti.base.prep-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-12-17 13:54:31 -08:00
mmc mmc: core: apply NO_CMD23 quirk to some specific cards 2017-12-11 13:43:27 +01:00
mtd Rename superblock flags (MS_xyz -> SB_xyz) 2017-11-27 13:05:09 -08:00
mux
net net: qcom/emac: Reduce timeout for mdio read/write 2017-12-15 15:46:19 -05:00
nfc treewide: setup_timer() -> timer_setup() (2 field) 2017-11-21 15:57:09 -08:00
ntb treewide: setup_timer() -> timer_setup() 2017-11-21 15:57:07 -08:00
nubus m68k updates for 4.15 2017-11-13 12:10:24 -08:00
nvdimm libnvdimm for 4.15 2017-11-17 09:51:57 -08:00
nvme nvme/multipath: Use blk_path_error 2018-01-10 10:52:18 -07:00
nvmem Char/Misc patches for 4.15-rc1 2017-11-16 09:10:59 -08:00
of of_mdio / mdiobus: ensure mdio devices have fwnode correctly populated 2017-12-13 15:01:47 -05:00
opp
oprofile License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
parisc License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
parport Char/Misc patches for 4.15-rc1 2017-11-16 09:10:59 -08:00
pci Power management fix for v4.15-rc4 2017-12-14 18:25:03 -08:00
pcmcia drivers/pcmcia/sa1111_badge4.c: avoid unused function warning 2017-11-17 16:10:04 -08:00
perf arm64 updates for 4.15 2017-11-15 10:56:56 -08:00
phy USB/PHY patches for 4.15-rc1 2017-11-13 21:14:07 -08:00
pinctrl pinctrl: sunxi: Disable strict mode for H5 driver 2017-11-30 16:50:43 +01:00
platform platform/x86: dell-wmi: check for kmalloc() errors 2017-12-11 17:26:03 -08:00
pnp License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
power power supply and reset changes for the v4.15 series 2017-11-15 13:37:15 -08:00
powercap
pps treewide: setup_timer() -> timer_setup() 2017-11-21 15:57:07 -08:00
ps3
ptp xen: features and fixes for v4.15-rc1 2017-11-16 13:06:27 -08:00
pwm pwm: Changes for v4.15-rc1 2017-11-22 21:09:18 -10:00
rapidio Merge branch 'akpm' (patches from Andrew) 2017-11-17 16:56:17 -08:00
ras Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-11-13 17:56:58 -08:00
regulator - New Drivers 2017-11-16 09:15:57 -08:00
remoteproc remoteproc updates for v4.15 2017-11-17 20:14:10 -08:00
reset ARM: SoC driver updates for v4.15 2017-11-16 16:05:01 -08:00
rpmsg rpmsg updates for v4.15 2017-11-17 20:12:08 -08:00
rtc Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-11-25 08:37:16 -10:00
s390 s390/qeth: update takeover IPs after configuration change 2017-12-15 11:29:43 -05:00
sbus Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc 2017-11-17 20:21:44 -08:00
scsi SCSI fixes on 20171215 2017-12-15 12:51:42 -08:00
sfi
sh A couple of dma-mapping updates: 2017-11-14 16:54:12 -08:00
sn
soc meson-gx-socinfo: Fix package id parsing 2017-11-30 15:29:44 -08:00
spi Merge remote-tracking branches 'spi/topic/sh-msiof', 'spi/topic/slave', 'spi/topic/spreadtrum' and 'spi/topic/tegra114' into spi-next 2017-11-10 21:33:51 +00:00
spmi
ssb License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
staging Merge tag 'staging-4.15-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging 2017-12-15 12:59:48 -08:00
target target: Use sgl_alloc_order() and sgl_free() 2018-01-06 09:18:00 -07:00
tc
tee optee: fix invalid of_node_put() in optee_driver_init() 2017-11-29 10:24:57 +01:00
thermal Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux 2017-11-17 14:31:27 -08:00
thunderbolt Char/Misc patches for 4.15-rc1 2017-11-16 09:10:59 -08:00
tty serdev: ttyport: fix tty locking in close 2017-11-28 16:00:50 +01:00
uio License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
usb USB: core: prevent malicious bNumInterfaces overflow 2017-12-13 12:28:43 +01:00
uwb treewide: setup_timer() -> timer_setup() 2017-11-21 15:57:07 -08:00
vfio VFIO Updates for Linux v4.15 2017-11-14 16:47:47 -08:00
vhost vhost: fix skb leak in handle_rx() 2017-12-02 21:31:03 -05:00
video fbdev changes for v4.15: 2017-11-20 21:50:24 -10:00
virt
virtio virtio_mmio: fix devm cleanup 2017-12-14 21:01:40 +02:00
vlynq
vme Char/Misc patches for 4.15-rc1 2017-11-16 09:10:59 -08:00
w1 Char/Misc patches for 4.15-rc1 2017-11-16 09:10:59 -08:00
watchdog treewide: setup_timer() -> timer_setup() 2017-11-21 15:57:07 -08:00
xen xen: fixes for 4.15-rc4 2017-12-15 11:32:09 -08:00
zorro License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
Kconfig Merge branches 'pm-cpufreq-sched' and 'pm-opp' 2017-11-13 01:40:52 +01:00
Makefile usb: build drivers/usb/common/ when USB_SUPPORT is set 2017-11-28 15:17:49 +01:00