DRM_VMW_EVENT_FENCE_SIGNALED (struct drm_vmw_event_fence) and
DRM_EVENT_VBLANK (struct drm_event_vblank) pass timestamps in 32-bit
seconds/microseconds format.
As of commit c61eef726a78 ("drm: add support for monotonic vblank
timestamps"), other DRM drivers use monotonic times for drm_event_vblank,
but vmwgfx still uses CLOCK_REALTIME for both events, which suffers from
the y2038/y2106 overflow as well as time jumps.
For consistency, this changes vmwgfx to use ktime_get_ts64 as well,
which solves those problems and avoids the deprecated do_gettimeofday()
function.
This should be transparent to to user space, as long as it doesn't
compare the time against the result of gettimeofday().
Link: https://patchwork.kernel.org/patch/10076599/
Signed-off-by: Arnd Bergmann <arnd(a)arndb.de>
---
Originally sent on Nov 27. Sinclair Yeh said he'd pick it up
for the next pull request, but it's not in linux-next yet.
Resending the unchanged patch, please pick it up when you have time,
or feel free to ignore this email in case it's already in some tree
that just isn't part of linux-next but will be sent during the
next merge window.
---
drivers/gpu/drm/vmwgfx/vmwgfx_fence.c | 9 +++++----
1 file changed, 5 insertions(+), 4 deletions(-)
diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_fence.c b/drivers/gpu/drm/vmwgfx/vmwgfx_fence.c
index 6c5c75cf5e6c..9ed544f8958f 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_fence.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_fence.c
@@ -901,11 +901,12 @@ static void vmw_event_fence_action_seq_passed(struct vmw_fence_action *action)
spin_lock_irq(&dev->event_lock);
if (likely(eaction->tv_sec != NULL)) {
- struct timeval tv;
+ struct timespec64 ts;
- do_gettimeofday(&tv);
- *eaction->tv_sec = tv.tv_sec;
- *eaction->tv_usec = tv.tv_usec;
+ ktime_get_ts64(&ts);
+ /* monotonic time, so no y2038 overflow */
+ *eaction->tv_sec = ts.tv_sec;
+ *eaction->tv_usec = ts.tv_nsec / NSEC_PER_USEC;
}
drm_send_event_locked(dev, eaction->event);
--
2.9.0
getnstimeofday() is deprecated, so I'm converting this to use
ktime_get_real_ts64() as a safe replacement. I considered using
ktime_get_real() instead, but since the algorithm here depends
on the exact timing, I decided to introduce fewer changes
and leave the code that determines the nanoseconds since the
last seconds wrap untouched.
It's not entirely clear to me whether we should also change the
time base to CLOCK_BOOTTIME or CLOCK_TAI. With boottime, we
would be independent of changes due to settimeofday() and only
see the speed adjustment from the upstream clock source, with
the downside of having the signal be at an arbirary offset
from the start of the UTC second signal. With CLOCK_TAI, we
would use the same offset from the UTC second as before and
still suffer from settimeofday() adjustments, but would be
less confused during leap seconds.
Both boottime and tai only offer usable (i.e. avoiding ktime_t
to timespec64 conversion) interfaces for ktime_t though, so
either way, changing it wouldn't take significantly more work.
CLOCK_MONOTONIC could be used with ktime_get_ts64(), but would
lose synchronization across a suspend/resume cycle, which seems
worse.
Acked-by: Rodolfo Giometti <giometti(a)enneenne.com>
Signed-off-by: Arnd Bergmann <arnd(a)arndb.de>
---
Sent on Nov 28 originally, got an Ack, but nobody picked it up.
Andrew, it seems you handled some pps generator patches
in the past, can you take this one through -mm?
---
drivers/pps/generators/pps_gen_parport.c | 40 ++++++++++++++++----------------
1 file changed, 20 insertions(+), 20 deletions(-)
diff --git a/drivers/pps/generators/pps_gen_parport.c b/drivers/pps/generators/pps_gen_parport.c
index dcd39fba6ddd..51cfde6afffd 100644
--- a/drivers/pps/generators/pps_gen_parport.c
+++ b/drivers/pps/generators/pps_gen_parport.c
@@ -70,7 +70,7 @@ static long hrtimer_error = SAFETY_INTERVAL;
/* the kernel hrtimer event */
static enum hrtimer_restart hrtimer_event(struct hrtimer *timer)
{
- struct timespec expire_time, ts1, ts2, ts3, dts;
+ struct timespec64 expire_time, ts1, ts2, ts3, dts;
struct pps_generator_pp *dev;
struct parport *port;
long lim, delta;
@@ -78,7 +78,7 @@ static enum hrtimer_restart hrtimer_event(struct hrtimer *timer)
/* We have to disable interrupts here. The idea is to prevent
* other interrupts on the same processor to introduce random
- * lags while polling the clock. getnstimeofday() takes <1us on
+ * lags while polling the clock. ktime_get_real_ts64() takes <1us on
* most machines while other interrupt handlers can take much
* more potentially.
*
@@ -88,22 +88,22 @@ static enum hrtimer_restart hrtimer_event(struct hrtimer *timer)
local_irq_save(flags);
/* first of all we get the time stamp... */
- getnstimeofday(&ts1);
- expire_time = ktime_to_timespec(hrtimer_get_softexpires(timer));
+ ktime_get_real_ts64(&ts1);
+ expire_time = ktime_to_timespec64(hrtimer_get_softexpires(timer));
dev = container_of(timer, struct pps_generator_pp, timer);
lim = NSEC_PER_SEC - send_delay - dev->port_write_time;
/* check if we are late */
if (expire_time.tv_sec != ts1.tv_sec || ts1.tv_nsec > lim) {
local_irq_restore(flags);
- pr_err("we are late this time %ld.%09ld\n",
- ts1.tv_sec, ts1.tv_nsec);
+ pr_err("we are late this time %lld.%09ld\n",
+ (s64)ts1.tv_sec, ts1.tv_nsec);
goto done;
}
/* busy loop until the time is right for an assert edge */
do {
- getnstimeofday(&ts2);
+ ktime_get_real_ts64(&ts2);
} while (expire_time.tv_sec == ts2.tv_sec && ts2.tv_nsec < lim);
/* set the signal */
@@ -113,25 +113,25 @@ static enum hrtimer_restart hrtimer_event(struct hrtimer *timer)
/* busy loop until the time is right for a clear edge */
lim = NSEC_PER_SEC - dev->port_write_time;
do {
- getnstimeofday(&ts2);
+ ktime_get_real_ts64(&ts2);
} while (expire_time.tv_sec == ts2.tv_sec && ts2.tv_nsec < lim);
/* unset the signal */
port->ops->write_control(port, NO_SIGNAL);
- getnstimeofday(&ts3);
+ ktime_get_real_ts64(&ts3);
local_irq_restore(flags);
/* update calibrated port write time */
- dts = timespec_sub(ts3, ts2);
+ dts = timespec64_sub(ts3, ts2);
dev->port_write_time =
- (dev->port_write_time + timespec_to_ns(&dts)) >> 1;
+ (dev->port_write_time + timespec64_to_ns(&dts)) >> 1;
done:
/* update calibrated hrtimer error */
- dts = timespec_sub(ts1, expire_time);
- delta = timespec_to_ns(&dts);
+ dts = timespec64_sub(ts1, expire_time);
+ delta = timespec64_to_ns(&dts);
/* If the new error value is bigger then the old, use the new
* value, if not then slowly move towards the new value. This
* way it should be safe in bad conditions and efficient in
@@ -161,17 +161,17 @@ static void calibrate_port(struct pps_generator_pp *dev)
long acc = 0;
for (i = 0; i < (1 << PORT_NTESTS_SHIFT); i++) {
- struct timespec a, b;
+ struct timespec64 a, b;
unsigned long irq_flags;
local_irq_save(irq_flags);
- getnstimeofday(&a);
+ ktime_get_real_ts64(&a);
port->ops->write_control(port, NO_SIGNAL);
- getnstimeofday(&b);
+ ktime_get_real_ts64(&b);
local_irq_restore(irq_flags);
- b = timespec_sub(b, a);
- acc += timespec_to_ns(&b);
+ b = timespec64_sub(b, a);
+ acc += timespec64_to_ns(&b);
}
dev->port_write_time = acc >> PORT_NTESTS_SHIFT;
@@ -180,9 +180,9 @@ static void calibrate_port(struct pps_generator_pp *dev)
static inline ktime_t next_intr_time(struct pps_generator_pp *dev)
{
- struct timespec ts;
+ struct timespec64 ts;
- getnstimeofday(&ts);
+ ktime_get_real_ts64(&ts);
return ktime_set(ts.tv_sec +
((ts.tv_nsec > 990 * NSEC_PER_MSEC) ? 1 : 0),
--
2.9.0
On Thu, Jan 4, 2018 at 9:00 AM, Christoph Hellwig <hch(a)lst.de> wrote:
> +}
> +
> +SYSCALL_DEFINE6(io_pgetevents,
> + aio_context_t, ctx_id,
> + long, min_nr,
> + long, nr,
> + struct io_event __user *, events,
> + struct timespec __user *, timeout,
> + const sigset_t __user *, sigmask)
> +{
> +COMPAT_SYSCALL_DEFINE6(io_pgetevents,
> + compat_aio_context_t, ctx_id,
> + compat_long_t, min_nr,
> + compat_long_t, nr,
> + struct io_event __user *, events,
> + struct compat_timespec __user *, timeout,
> + const compat_sigset_t __user *, sigmask)
> +{
Hmm, these two new syscall entry points turn into four when we add in
support for 64-bit time_t, as we'd have to support all combinations of 32/64
bit aio_context_t and time_t.
Would it be better to start this interface out by defining it using a 64-bit
timeout structure? The downside would be that the user space syscall
wrappers have to start out with a conversion, if we don't do it, then
the opposite conversion would have to get added later.
Arnd
The series is aimed at making input events y2038 safe.
It extends the lifetime of the realtime timestamps in the
events to year 2106.
The series is also a necessary update as glibc is set to provide
64 bit time_t support for 32 bit binaries. glibc plan is detailed
at https://sourceware.org/glibc/wiki/Y2038ProofnessDesign .
The series is a result of discussions with Arnd Bergmann and
Dmitry Torokhov at last Plumbers.
The plan is to deprecate realtime timestamps anyway as they
are not appropriate for these timestamps as noted in the patch
a80b83b7b8 by John Stultz.
The design also updates the format of the input events read/ written
to the device nodes. This breaks 32 bit interface to the input
events at compile time as preferred by the maintainer.
The userspace library changes to libevdev, libuinput and mtdev
will be posted to the respective mailing groups for review.
Changes from v5:
* Dropped patch 1, since it has already been applied
* Combined patches 2 and 3
* Addressed minor review comments
Changes from v4:
* Dropped serio hil patch
Changes from v3:
* Updated uinput to support monotonic time only
* Addressed review comments
Changes from v2:
* Updated the design to break 32 bit interfaces at compile time.
Changes from v1:
* Updated changes according to review comments.
* Posted userspace library changes that go along with the series.
Deepa Dinamani (1):
input: Deprecate real timestamps beyond year 2106
drivers/input/evdev.c | 16 ++++++++++++----
drivers/input/input-compat.c | 8 ++++----
drivers/input/input-compat.h | 3 ++-
drivers/input/misc/uinput.c | 4 ++--
include/uapi/linux/input.h | 12 +++++++++++-
5 files changed, 31 insertions(+), 12 deletions(-)
base-commit: 0c1f9d81ac360d8ad31cbfd2bdcf44de8204188e
prerequisite-patch-id: 6c903c00c9d5191619efe9f26e2600197336e6b2
--
2.14.1
The series is aimed at making input events y2038 safe.
It extends the lifetime of the realtime timestamps in the
events to year 2106.
The series is also a necessary update as glibc is set to provide
64 bit time_t support for 32 bit binaries. glibc plan is detailed
at https://sourceware.org/glibc/wiki/Y2038ProofnessDesign .
The series is a result of discussions with Arnd Bergmann and
Dmitry Torokhov at last Plumbers.
The plan is to deprecate realtime timestamps anyway as they
are not appropriate for these timestamps as noted in the patch
a80b83b7b8 by John Stultz.
The design also updates the format of the input events read/ written
to the device nodes. This breaks 32 bit interface to the input
events at compile time as preferred by the maintainer.
The userspace library changes to libevdev, libuinput and mtdev
will be posted to the respective mailing groups for review.
Changes from v4:
* Dropped serio hil patch
Changes from v3:
* Updated uinput to support monotonic time only
* Addressed review comments
Changes from v2:
* Updated the design to break 32 bit interfaces at compile time.
Changes from v1:
* Updated changes according to review comments.
* Posted userspace library changes that go along with the series.
Deepa Dinamani (3):
uinput: Use monotonic times for uinput timestamps.
input: evdev: Replace timeval with timespec64
input: Deprecate real timestamps beyond year 2106
drivers/input/evdev.c | 43 +++++++++++++++++++++++++++----------------
drivers/input/input-compat.c | 11 ++++++-----
drivers/input/input-compat.h | 3 ++-
drivers/input/misc/uinput.c | 5 ++++-
include/uapi/linux/input.h | 12 +++++++++++-
5 files changed, 50 insertions(+), 24 deletions(-)
base-commit: 0c1f9d81ac360d8ad31cbfd2bdcf44de8204188e
--
2.14.1
The series is a preparation series for individual architectures
to use 64 bit time_t syscalls in compat and 32 bit emulation modes.
This is a follow up to the series Arnd Bergmann posted:
https://sourceware.org/ml/libc-alpha/2015-05/msg00070.html [1]
Big picture is as per the lwn article:
https://lwn.net/Articles/643234/ [2]
The series is directed at converting posix clock syscalls:
clock_gettime, clock_settime, clock_getres and clock_nanosleep
to use a new data structure __kernel_timespec at syscall boundaries.
__kernel_timespec maintains 64 bit time_t across all execution modes.
vdso will be handled as part of each architecture when they enable
support for 64 bit time_t.
The compat syscalls are repurposed to provide backward compatibility
by using them as native syscalls as well for 32 bit architectures.
They will continue to use timespec at syscall boundaries.
CONFIG_64_BIT_TIME controls whether the syscalls use __kernel_timespec
or timespec at syscall boundaries.
The series does the following:
1. Enable compat syscalls on 32 bit architectures.
2. Add a new __kernel_timespec type to be used as the data structure
for all the new syscalls.
3. Add new config CONFIG_64BIT_TIME(intead of the CONFIG_COMPAT_TIME in
[1] and [2] to switch to new definition of __kernel_timespec. It is
the same as struct timespec otherwise.
4. Add new CONFIG_32BIT_TIME to conditionally compile compat syscalls.
* Changes since v1:
* Introduce CONFIG_32BIT_TIME
* Fixed zeroing out of higher order bits of tv_nsec
* Included Arnd's changes to fix up use of compat headers
I decided against using LEGACY_TIME_SYSCALLS to conditionally compile
legacy time syscalls such as sys_nanosleep because this will need to
enclose compat_sys_nanosleep as well. So, defining it as
config LEGACY_TIME_SYSCALLS
def_bool 64BIT || !64BIT_TIME
will not include compat_sys_nanosleep. We will instead need a new config to
exclusively mark legacy syscalls.
Deepa Dinamani (10):
compat: Make compat helpers independent of CONFIG_COMPAT
include: Move compat_timespec/ timeval to compat_time.h
compat: enable compat_get/put_timespec64 always
arch: introduce CONFIG_64BIT_TIME
arch: Introduce CONFIG_COMPAT_32BIT_TIME
posix-clocks: Make compat syscalls depend on CONFIG_COMPAT_32BIT_TIME
include: Add new y2038 safe __kernel_timespec
fix get_timespec64() for y2038 safe compat interfaces
change time types to new y2038 safe __kernel_* types
nanosleep: change time types to safe __kernel_* types
arch/Kconfig | 18 +++++++
arch/arm64/include/asm/compat.h | 11 ----
arch/arm64/include/asm/stat.h | 1 +
arch/arm64/kernel/hw_breakpoint.c | 1 -
arch/arm64/kernel/perf_regs.c | 2 +-
arch/arm64/kernel/process.c | 1 -
arch/mips/include/asm/compat.h | 11 ----
arch/mips/kernel/signal32.c | 2 +-
arch/parisc/include/asm/compat.h | 11 ----
arch/powerpc/include/asm/compat.h | 11 ----
arch/powerpc/kernel/asm-offsets.c | 2 +-
arch/powerpc/oprofile/backtrace.c | 2 +-
arch/s390/hypfs/hypfs_sprp.c | 1 -
arch/s390/include/asm/compat.h | 11 ----
arch/s390/include/asm/elf.h | 3 +-
arch/s390/kvm/priv.c | 1 -
arch/s390/pci/pci_clp.c | 1 -
arch/sparc/include/asm/compat.h | 11 ----
arch/tile/include/asm/compat.h | 11 ----
arch/x86/events/core.c | 2 +-
arch/x86/include/asm/compat.h | 11 ----
arch/x86/include/asm/ftrace.h | 2 +-
arch/x86/include/asm/sys_ia32.h | 2 +-
arch/x86/kernel/sys_x86_64.c | 2 +-
drivers/s390/block/dasd_ioctl.c | 1 -
drivers/s390/char/fs3270.c | 1 -
drivers/s390/char/sclp_ctl.c | 1 -
drivers/s390/char/vmcp.c | 1 -
drivers/s390/cio/chsc_sch.c | 1 -
drivers/s390/net/qeth_core_main.c | 2 +-
drivers/staging/pi433/pi433_if.c | 2 +-
include/linux/compat.h | 11 ++--
include/linux/compat_time.h | 23 +++++++++
include/linux/restart_block.h | 7 +--
include/linux/syscalls.h | 12 ++---
include/linux/time.h | 4 +-
include/linux/time64.h | 10 +++-
include/uapi/asm-generic/posix_types.h | 1 +
include/uapi/linux/time.h | 7 +++
kernel/Makefile | 2 +-
kernel/compat.c | 92 ++++++++++++++++++----------------
kernel/time/hrtimer.c | 10 ++--
kernel/time/posix-stubs.c | 12 +++--
kernel/time/posix-timers.c | 24 ++++++---
kernel/time/time.c | 10 +++-
45 files changed, 175 insertions(+), 190 deletions(-)
create mode 100644 include/linux/compat_time.h
base-commit: b0a84f19a5161418d4360cd57603e94ed489915e
--
2.14.1
Cc: acme(a)kernel.org
Cc: benh(a)kernel.crashing.org
Cc: borntraeger(a)de.ibm.com
Cc: catalin.marinas(a)arm.com
Cc: cmetcalf(a)mellanox.com
Cc: cohuck(a)redhat.com
Cc: davem(a)davemloft.net
Cc: deller(a)gmx.de
Cc: devel(a)driverdev.osuosl.org
Cc: gerald.schaefer(a)de.ibm.com
Cc: gregkh(a)linuxfoundation.org
Cc: heiko.carstens(a)de.ibm.com
Cc: hoeppner(a)linux.vnet.ibm.com
Cc: hpa(a)zytor.com
Cc: jejb(a)parisc-linux.org
Cc: jwi(a)linux.vnet.ibm.com
Cc: linux-api(a)vger.kernel.org
Cc: linux-arch(a)vger.kernel.org
Cc: linux-kernel(a)vger.kernel.org
Cc: linux-mips(a)linux-mips.org
Cc: linux-parisc(a)vger.kernel.org
Cc: linuxppc-dev(a)lists.ozlabs.org
Cc: linux-s390(a)vger.kernel.org
Cc: mark.rutland(a)arm.com
Cc: mingo(a)redhat.com
Cc: mpe(a)ellerman.id.au
Cc: oberpar(a)linux.vnet.ibm.com
Cc: oprofile-list(a)lists.sf.net
Cc: paulus(a)samba.org
Cc: peterz(a)infradead.org
Cc: ralf(a)linux-mips.org
Cc: rostedt(a)goodmis.org
Cc: rric(a)kernel.org
Cc: schwidefsky(a)de.ibm.com
Cc: sebott(a)linux.vnet.ibm.com
Cc: sparclinux(a)vger.kernel.org
Cc: sth(a)linux.vnet.ibm.com
Cc: ubraun(a)linux.vnet.ibm.com
Cc: will.deacon(a)arm.com
Cc: x86(a)kernel.org
The series is aimed at making input events y2038 safe.
It extends the lifetime of the realtime timestamps in the
events to year 2106.
The series is also a necessary update as glibc is set to provide
64 bit time_t support for 32 bit binaries. glibc plan is detailed
at https://sourceware.org/glibc/wiki/Y2038ProofnessDesign .
The series is a result of discussions with Arnd Bergmann and
Dmitry Torokhov at last Plumbers.
The plan is to deprecate realtime timestamps anyway as they
are not appropriate for these timestamps as noted in the patch
a80b83b7b8 by John Stultz.
The design also updates the format of the input events read/ written
to the device nodes. This breaks 32 bit interface to the input
events at compile time as preferred by the maintainer.
The userspace library changes to libevdev, libuinput and mtdev
will be posted to the respective mailing groups for review.
Changes from v3:
* Updated uinput to support monotonic time only
* Addressed review comments
Changes from v2:
* Updated the design to break 32 bit interfaces at compile time.
Changes from v1:
* Updated changes according to review comments.
* Posted userspace library changes that go along with the series.
Deepa Dinamani (4):
uinput: Use monotonic times for uinput timestamps.
input: evdev: Replace timeval with timespec64
input: Deprecate real timestamps beyond year 2106
input: serio: Replace timeval by timespec64
drivers/input/evdev.c | 43 +++++++++++++++++++++++++---------------
drivers/input/input-compat.c | 11 +++++-----
drivers/input/input-compat.h | 3 ++-
drivers/input/misc/uinput.c | 5 ++++-
drivers/input/serio/hil_mlc.c | 37 +++++++++++++++++-----------------
drivers/input/serio/hp_sdc.c | 17 ++++++++--------
drivers/input/serio/hp_sdc_mlc.c | 10 +++++-----
include/linux/hil_mlc.h | 6 +++---
include/linux/hp_sdc.h | 6 +++---
include/uapi/linux/input.h | 12 ++++++++++-
10 files changed, 88 insertions(+), 62 deletions(-)
base-commit: b0a84f19a5161418d4360cd57603e94ed489915e
--
2.14.1