Commit Graph

1186123 Commits

Author SHA1 Message Date
Rob Herring
0a8b07c77e clocksource: Explicitly include correct DT includes
The DT of_device.h and of_platform.h date back to the separate
of_platform_bus_type before it as merged into the regular platform bus.
As part of that merge prepping Arm DT support 13 years ago, they
"temporarily" include each other. They also include platform_device.h
and of.h. As a result, there's a pretty much random mix of those include
files used throughout the tree. In order to detangle these headers and
replace the implicit includes with struct declarations, users need to
explicitly include the correct includes.

Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20230714174409.4053843-1-robh@kernel.org
2023-08-18 12:16:01 +02:00
Mans Rullgard
7e5bac610d clocksource/drivers/sun5i: Convert to platform device driver
Convert the sun5i hstimer driver to a platform device driver.
This makes it work again on A20 and other systems where the
clock is provided by a platform device driver.

Fixes: 7ec03b588d ("clk: sunxi-ng: Convert early providers to platform drivers")
Signed-off-by: Mans Rullgard <mans@mansr.com>
Acked-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Acked-by: Maxime Ripard <mripard@kernel.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20230630201800.16501-4-mans@mansr.com
2023-08-18 12:15:22 +02:00
Mans Rullgard
0b38dd178d clocksource/drivers/sun5i: Remove pointless struct
Remove the pointless struct added in the previous patch to make
the diff smaller.

Signed-off-by: Mans Rullgard <mans@mansr.com>
Acked-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Acked-by: Maxime Ripard <mripard@kernel.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20230630201800.16501-3-mans@mansr.com
2023-08-18 12:15:13 +02:00
Mans Rullgard
7ded803873 clocksource/drivers/sun5i: Remove duplication of code and data
Move the clocksource and clock_event_device structs into the main
struct sun5i_timer, and update the code for the new layout.  This
removes a lot of duplication of both code and data.

Signed-off-by: Mans Rullgard <mans@mansr.com>
Acked-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Acked-by: Maxime Ripard <mripard@kernel.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20230630201800.16501-2-mans@mansr.com
2023-08-18 12:15:06 +02:00
Tom Rix
bd0f3aac47 clocksource/drivers/loongson1: Set variable ls1x_timer_lock storage-class-specifier to static
smatch reports
drivers/clocksource/timer-loongson1-pwm.c:31:1: warning: symbol
  'ls1x_timer_lock' was not declared. Should it be static?

This variable is only used in its defining file, so it should be static.

Signed-off-by: Tom Rix <trix@redhat.com>
Acked-by: Keguang Zhang <keguang.zhang@gmail.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20230702133113.3438049-1-trix@redhat.com
2023-08-18 12:13:03 +02:00
Walter Chang
e7d65e40ab clocksource/drivers/arm_arch_timer: Disable timer before programming CVAL
Due to the fact that the use of `writeq_relaxed()` to program CVAL is
not guaranteed to be atomic, it is necessary to disable the timer before
programming CVAL.

However, if the MMIO timer is already enabled and has not yet expired,
there is a possibility of unexpected behavior occurring: when the CPU
enters the idle state during this period, and if the CPU's local event
is earlier than the broadcast event, the following process occurs:

tick_broadcast_enter()
  tick_broadcast_oneshot_control(TICK_BROADCAST_ENTER)
    __tick_broadcast_oneshot_control()
      ___tick_broadcast_oneshot_control()
        tick_broadcast_set_event()
          clockevents_program_event()
            set_next_event_mem()

During this process, the MMIO timer remains enabled while programming
CVAL. To prevent such behavior, disable timer explicitly prior to
programming CVAL.

Fixes: 8b82c4f883 ("clocksource/drivers/arm_arch_timer: Move MMIO timer programming over to CVAL")
Cc: stable@vger.kernel.org
Signed-off-by: Walter Chang <walter.chang@mediatek.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20230717090735.19370-1-walter.chang@mediatek.com
2023-08-18 12:06:16 +02:00
Neil Armstrong
c42b7a3852 dt-bindings: timer: oxsemi,rps-timer: remove obsolete bindings
Due to lack of maintenance and stall of development for a few years now,
and since no new features will ever be added upstream, remove the
OX810 and OX820 timer bindings.

Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Daniel Golle <daniel@makrotopia.org>
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
Acked-by: Andy Shevchenko <andy@kernel.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20230630-topic-oxnas-upstream-remove-v2-4-fb6ab3dea87c@linaro.org
2023-07-13 14:46:34 +02:00
Neil Armstrong
56f99cdc5b clocksource/drivers/timer-oxnas-rps: Remove obsolete timer driver
Due to lack of maintenance and stall of development for a few years now,
and since no new features will ever be added upstream, remove support
for OX810 and OX820 timer.

Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Daniel Golle <daniel@makrotopia.org>
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
Acked-by: Andy Shevchenko <andy@kernel.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20230630-topic-oxnas-upstream-remove-v2-3-fb6ab3dea87c@linaro.org
2023-07-13 14:46:17 +02:00
Feng Mingxi
8b5bf64c89 clocksource/drivers/cadence-ttc: Fix memory leak in ttc_timer_probe
Smatch reports:
drivers/clocksource/timer-cadence-ttc.c:529 ttc_timer_probe()
warn: 'timer_baseaddr' from of_iomap() not released on lines: 498,508,516.

timer_baseaddr may have the problem of not being released after use,
I replaced it with the devm_of_iomap() function and added the clk_put()
function to cleanup the "clk_ce" and "clk_cs".

Fixes: e932900a32 ("arm: zynq: Use standard timer binding")
Fixes: 70504f311d ("clocksource/drivers/cadence_ttc: Convert init function to return error")
Signed-off-by: Feng Mingxi <m202271825@hust.edu.cn>
Reviewed-by: Dongliang Mu <dzm91@hust.edu.cn>
Acked-by: Michal Simek <michal.simek@amd.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20230425065611.702917-1-m202271825@hust.edu.cn
2023-06-23 09:33:44 +02:00
Sergio Paracuellos
6d0d4df8e7 dt-bindings: timers: Add Ralink SoCs timer
Add YAML documentation for the timer which is present on Ralink SoCs.

Signed-off-by: Sergio Paracuellos <sergio.paracuellos@gmail.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20230620100231.1412582-1-sergio.paracuellos@gmail.com
2023-06-23 09:33:43 +02:00
Michael Kelley
e5313f1c54 clocksource/drivers/hyper-v: Rework clocksource and sched clock setup
Current code assigns either the Hyper-V TSC page or MSR-based ref counter
as the sched clock. This may be sub-optimal in two cases. First, if there
is hardware support to ensure consistent TSC frequency across live
migrations and Hyper-V is using that support, the raw TSC is a faster
source of time than the Hyper-V TSC page.  Second, the MSR-based ref
counter is relatively slow because reads require a trap to the hypervisor.
As such, it should never be used as the sched clock. The native sched
clock based on the raw TSC or jiffies is much better.

Rework the sched clock setup so it is set to the TSC page only if
Hyper-V indicates that the TSC may have inconsistent frequency across
live migrations. Also, remove the code that sets the sched clock to
the MSR-based ref counter. In the cases where it is not set, the sched
clock will then be the native sched clock.

As part of the rework, always enable both the TSC page clocksource and
the MSR-based ref counter clocksource. Set the ratings so the TSC page
clocksource is preferred. While the MSR-based ref counter clocksource
is unlikely to ever be the default, having it available for manual
selection is convenient for development purposes.

Signed-off-by: Michael Kelley <mikelley@microsoft.com>
Reviewed-by: Dexuan Cui <decui@microsoft.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/1687201360-16003-1-git-send-email-mikelley@microsoft.com
2023-06-23 09:33:43 +02:00
Stanislav Jakubek
038d454ad9 dt-bindings: timer: brcm,kona-timer: convert to YAML
Convert Broadcom Kona family timer bindings to DT schema.

Changes during conversion:
  - drop deprecated compatible (it's been deprecated for ~10 years)

Signed-off-by: Stanislav Jakubek <stano.jakubek@gmail.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20230618144635.GA22166@standask-GA-A55M-S2HP
2023-06-23 09:33:43 +02:00
Uwe Kleine-König
281bf6b94a clocksource/drivers/imx-gpt: Fold <soc/imx/timer.h> into its only user
Only the imx-gpt timer driver makes use of enum imx_gpt_type that is
otherwise unused. Move its definition into the timer-imx-gpt driver.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20230328100531.879485-3-u.kleine-koenig@pengutronix.de
2023-06-23 09:33:43 +02:00
Uwe Kleine-König
011da162da clk: imx: Drop inclusion of unused header <soc/imx/timer.h>
The clk drivers use none of the symbols defined in <soc/imx/timer.h>.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20230328100531.879485-2-u.kleine-koenig@pengutronix.de
2023-06-23 09:33:43 +02:00
Uwe Kleine-König
95aded1b1c clocksource/drivers/imx-gpt: Use only a single name for functions
When looking at the data structs defining the different behaviours of
the GPT blocks in different SoCs it's not helpful that the same
functions are used with different names.

So drop the cpp defines and use the original names.

This commit was generated using:

	perl -i -e 'my %m; while (<>) { if (/^#define (imx[a-zA-Z0-6_]*)\s(imx[a-zA-Z0-6_]*)/) {$m{$1} = $2; } else { foreach my $f (keys %m) {s/$f/$m{$f}/; } print; } }' drivers/clocksource/timer-imx-gpt.c

This patch has no effect on the generated code.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20230328091514.874724-1-u.kleine-koenig@pengutronix.de
2023-06-19 17:31:56 +02:00
Keguang Zhang
e738521a11 clocksource/drivers/loongson1: Move PWM timer to clocksource framework
This patch moves most part of arch/mips/loongson32/common/time.c
into drivers/clocksource.

Adapt the driver to clocksource framework with devicetree support
and updates Kconfig/Makefile options.

Signed-off-by: Keguang Zhang <keguang.zhang@gmail.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20230512103724.587760-4-keguang.zhang@gmail.com
2023-06-19 17:07:03 +02:00
Keguang Zhang
b25efff2a6 dt-bindings: timer: Add Loongson-1 clocksource
Add devicetree binding document for Loongson-1 clocksource.

Signed-off-by: Keguang Zhang <keguang.zhang@gmail.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20230512103724.587760-3-keguang.zhang@gmail.com
2023-06-19 17:06:55 +02:00
Keguang Zhang
9e130e2be4 MIPS: Loongson32: Remove deprecated PWM timer clocksource
The Loongson1 PWM timer will be moved to clocksource framework.
Then, the old driver is no longer needed.
Remove the deprecated code and update the Kconfig.

Signed-off-by: Keguang Zhang <keguang.zhang@gmail.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20230512103724.587760-2-keguang.zhang@gmail.com
2023-06-19 17:06:55 +02:00
Paul Cercueil
ea95051063 clocksource/drivers/ingenic-timer: Use pm_sleep_ptr() macro
The use of the pm_sleep_ptr() macro allows the compiler to always see
the dev_pm_ops structure and related functions, while still allowing the
unused code to be removed, without the need for the __maybe_unused
markings.

Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20230618153937.96649-1-paul@crapouillou.net
2023-06-19 16:17:42 +02:00
Sebastian Andrzej Siewior
2951580ba6 tracing/timer: Add missing hrtimer modes to decode_hrtimer_mode().
The trace output for the HRTIMER_MODE_.*_HARD modes is seen as a number
since these modes are not decoded. The author was not aware of the fancy
decoding function which makes the life easier.

Extend decode_hrtimer_mode() with the additional HRTIMER_MODE_.*_HARD
modes.

Fixes: ae6683d815 ("hrtimer: Introduce HARD expiry mode")
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Mukesh Ojha <quic_mojha@quicinc.com>
Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Link: https://lore.kernel.org/r/20230418143854.8vHWQKLM@linutronix.de
2023-06-19 09:09:14 +02:00
Arnd Bergmann
892f439ea1 posix-timers: Add sys_ni_posix_timers() prototype
The sys_ni_posix_timers() definition causes a warning when the declaration
is missing, so this needs to be added along with the normal syscalls,
outside of the #ifdef.

kernel/time/posix-stubs.c:26:17: error: no previous prototype for 'sys_ni_posix_timers' [-Werror=missing-prototypes]

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20230607142925.3126422-1-arnd@kernel.org
2023-06-18 22:41:53 +02:00
Wen Yang
a7e282c777 tick/rcu: Fix bogus ratelimit condition
The ratelimit logic in report_idle_softirq() is broken because the
exit condition is always true:

	static int ratelimit;

	if (ratelimit < 10)
		return false;  ---> always returns here

	ratelimit++;           ---> no chance to run

Make it check for >= 10 instead.

Fixes: 0345691b24 ("tick/rcu: Stop allowing RCU_SOFTIRQ in idle")
Signed-off-by: Wen Yang <wenyang.linux@foxmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/tencent_5AAA3EEAB42095C9B7740BE62FBF9A67E007@qq.com
2023-06-18 22:41:53 +02:00
Li zeming
fc4b4d96f7 alarmtimer: Remove unnecessary (void *) cast
Pointers of type void * do not require a type cast when they are assigned
to a real pointer.

Signed-off-by: Li zeming <zeming@nfschina.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20230609182059.4509-1-zeming@nfschina.com
2023-06-18 22:41:53 +02:00
Li zeming
986af8dc5a alarmtimer: Remove unnecessary initialization of variable 'ret'
ret is assigned before checked, so it does not need to initialize the
variable

Signed-off-by: Li zeming <zeming@nfschina.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20230609182856.4660-1-zeming@nfschina.com
2023-06-18 22:41:53 +02:00
Lukas Bulwahn
b9a40f24d8 posix-timers: Refer properly to CONFIG_HIGH_RES_TIMERS
Commit c78f261e5dcb ("posix-timers: Clarify posix_timer_fn() comments")
turns an ifdef CONFIG_HIGH_RES_TIMERS into an conditional on
"IS_ENABLED(CONFIG_HIGHRES_TIMERS)"; note that the new conditional refers
to "HIGHRES_TIMERS" not "HIGH_RES_TIMERS" as before.

Fix this typo introduced in that refactoring.

Fixes: c78f261e5dcb ("posix-timers: Clarify posix_timer_fn() comments")
Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20230609094643.26253-1-lukas.bulwahn@gmail.com
2023-06-18 22:41:53 +02:00
Thomas Gleixner
b96ce4931f posix-timers: Polish coding style in a few places
Make it consistent with the TIP tree documentation.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/r/20230425183313.888493625@linutronix.de
2023-06-18 22:41:53 +02:00
Thomas Gleixner
200dbd6d14 posix-timers: Remove pointless comments
Documenting the obvious is just consuming space for no value.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/r/20230425183313.832240451@linutronix.de
2023-06-18 22:41:52 +02:00
Thomas Gleixner
84999b8bdb posix-timers: Clarify posix_timer_fn() comments
Make the issues vs. SIG_IGN understandable and remove the 15 years old
promise that a proper solution is already on the horizon.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/874jnrdmrq.ffs@tglx
2023-06-18 22:41:52 +02:00
Thomas Gleixner
02972d7955 posix-timers: Clarify posix_timer_rearm() comment
Yet another incomprehensible piece of art.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/r/20230425183313.724863461@linutronix.de
2023-06-18 22:41:52 +02:00
Thomas Gleixner
c575689d66 posix-timers: Comment SIGEV_THREAD_ID properly
Replace the word salad.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/r/20230425183313.672220780@linutronix.de
2023-06-18 22:41:51 +02:00
Thomas Gleixner
52f090b164 posix-timers: Add proper comments in do_timer_create()
The comment about timer lifetime at the end of the function is misplaced
and uncomprehensible.

Make it understandable and put it at the right place. Add a new comment
about the visibility of the new timer ID to user space.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/r/20230425183313.619897296@linutronix.de
2023-06-18 22:41:51 +02:00
Thomas Gleixner
640fe745d7 posix-timers: Document nanosleep() details
The descriptions for common_nsleep() is wrong and common_nsleep_timens()
lacks any form of comment.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/r/20230425183313.567072835@linutronix.de
2023-06-18 22:41:51 +02:00
Thomas Gleixner
3561fcb402 posix-timers: Document sys_clock_settime() permissions in place
The documentation of sys_clock_settime() permissions is at a random place
and mostly word salad.

Remove it and add a concise comment into sys_clock_settime().

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/r/20230425183313.514700292@linutronix.de
2023-06-18 22:41:51 +02:00
Thomas Gleixner
65cade468d posix-timers: Document sys_clock_getoverrun()
Document the syscall in detail and with coherent sentences.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/r/20230425183313.462051641@linutronix.de
2023-06-18 22:41:50 +02:00
Thomas Gleixner
a86e928433 posix-timers: Document common_clock_get() correctly
Replace another confusing and inaccurate set of comments.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/r/20230425183313.409169321@linutronix.de
2023-06-18 22:41:50 +02:00
Thomas Gleixner
01679b5db7 posix-timers: Document sys_clock_getres() correctly
The decades old comment about Posix clock resolution is confusing at best.

Remove it and add a proper explanation to sys_clock_getres().

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/r/20230425183313.356427330@linutronix.de
2023-06-18 22:41:50 +02:00
Thomas Gleixner
8cc96ca2c7 posix-timers: Split release_posix_timers()
release_posix_timers() is called for cleaning up both hashed and unhashed
timers. The cases are differentiated by an argument and the usage is
hideous.

Seperate the actual free path out and use it for unhashed timers. Provide a
function for hashed timers.

No functional change.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/r/20230425183313.301432503@linutronix.de
2023-06-18 22:41:50 +02:00
Thomas Gleixner
11fbe6cd41 posix-timers: Remove pointless irqsafe from hash_lock
All usage of hash_lock is in thread context. No point in using
spin_lock_irqsave()/irqrestore() for a single usage site.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/r/20230425183313.249063953@linutronix.de
2023-06-18 22:41:49 +02:00
Thomas Gleixner
72786ff23d posix-timers: Set k_itimer:: It_signal to NULL on exit()
Technically it's not required to set k_itimer::it_signal to NULL on exit()
because there is no other thread anymore which could lookup the timer
concurrently.

Set it to NULL for consistency sake and add a comment to that effect.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/r/20230425183313.196462644@linutronix.de
2023-06-18 22:41:49 +02:00
Thomas Gleixner
028cf5eaa1 posix-timers: Annotate concurrent access to k_itimer:: It_signal
k_itimer::it_signal is read lockless in the RCU protected hash lookup, but
it can be written concurrently in the timer_create() and timer_delete()
path. Annotate these places with READ_ONCE() and WRITE_ONCE()

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/r/20230425183313.143596887@linutronix.de
2023-06-18 22:41:49 +02:00
Thomas Gleixner
ae88967d71 posix-timers: Add comments about timer lookup
Document how the timer ID validation in the hash table works.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/r/20230425183313.091081515@linutronix.de
2023-06-18 22:41:49 +02:00
Thomas Gleixner
8d44b958a1 posix-timers: Cleanup comments about timer ID tracking
Describe the hash table properly and remove the IDR leftover comments.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/r/20230425183313.038444551@linutronix.de
2023-06-18 22:41:48 +02:00
Thomas Gleixner
7d99090266 posix-timers: Clarify timer_wait_running() comment
Explain it better and add the CONFIG_POSIX_CPU_TIMERS_TASK_WORK=y aspect
for completeness.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/r/20230425183312.985681995@linutronix.de
2023-06-18 22:41:48 +02:00
Thomas Gleixner
8ce8849dd1 posix-timers: Ensure timer ID search-loop limit is valid
posix_timer_add() tries to allocate a posix timer ID by starting from the
cached ID which was stored by the last successful allocation.

This is done in a loop searching the ID space for a free slot one by
one. The loop has to terminate when the search wrapped around to the
starting point.

But that's racy vs. establishing the starting point. That is read out
lockless, which leads to the following problem:

CPU0	  	      	     	   CPU1
posix_timer_add()
  start = sig->posix_timer_id;
  lock(hash_lock);
  ...				   posix_timer_add()
  if (++sig->posix_timer_id < 0)
      			             start = sig->posix_timer_id;
     sig->posix_timer_id = 0;

So CPU1 can observe a negative start value, i.e. -1, and the loop break
never happens because the condition can never be true:

  if (sig->posix_timer_id == start)
     break;

While this is unlikely to ever turn into an endless loop as the ID space is
huge (INT_MAX), the racy read of the start value caught the attention of
KCSAN and Dmitry unearthed that incorrectness.

Rewrite it so that all id operations are under the hash lock.

Reported-by: syzbot+5c54bd3eb218bb595aa9@syzkaller.appspotmail.com
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/r/87bkhzdn6g.ffs@tglx
2023-06-18 22:41:48 +02:00
Thomas Gleixner
9d9e522010 posix-timers: Prevent RT livelock in itimer_delete()
itimer_delete() has a retry loop when the timer is concurrently expired. On
non-RT kernels this just spin-waits until the timer callback has completed,
except for posix CPU timers which have HAVE_POSIX_CPU_TIMERS_TASK_WORK
enabled.

In that case and on RT kernels the existing task could live lock when
preempting the task which does the timer delivery.

Replace spin_unlock() with an invocation of timer_wait_running() to handle
it the same way as the other retry loops in the posix timer code.

Fixes: ec8f954a40 ("posix-timers: Use a callback for cancel synchronization on PREEMPT_RT")
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/r/87v8g7c50d.ffs@tglx
2023-06-18 22:40:42 +02:00
Arnd Bergmann
b7a7ce1bb7 vdso/timens: Always provide arch_get_vdso_data() prototype for vdso
The arch_get_vdso_data() function is defined separately on each architecture,
but only called when CONFIG_TIME_NS is set. If the definition is a global
function, this causes a W=1 warning without TIME_NS:

arch/x86/entry/vdso/vma.c:35:19: error: no previous prototype for 'arch_get_vdso_data' [-Werror=missing-prototypes]

Move the prototype out of the #ifdef block to reliably turn off that
warning.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20230517131102.934196-15-arnd@kernel.org
2023-05-31 21:45:49 +02:00
Linus Torvalds
7877cb91f1 Linux 6.4-rc4 2023-05-28 07:49:00 -04:00
Linus Torvalds
f8b2507c26 Merge tag 'x86-urgent-2023-05-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 cpu fix from Thomas Gleixner:
 "A single fix for x86:

   - Prevent a bogus setting for the number of HT siblings, which is
     caused by the CPUID evaluation trainwreck of X86. That recomputes
     the value for each CPU, so the last CPU "wins". That can cause
     completely bogus sibling values"

* tag 'x86-urgent-2023-05-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/topology: Fix erroneous smp_num_siblings on Intel Hybrid platforms
2023-05-28 07:42:05 -04:00
Linus Torvalds
2d5438f4c6 Merge tag 'perf-urgent-2023-05-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Thomas Gleixner:
 "A small set of perf fixes:

   - Make the MSR-readout based CHA discovery work around broken
     discovery tables in some SPR firmwares.

   - Prevent saving PEBS configuration which has software bits set that
     cause a crash when restored into the relevant MSR"

* tag 'perf-urgent-2023-05-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/x86/uncore: Correct the number of CHAs on SPR
  perf/x86/intel: Save/restore cpuc->active_pebs_data_cfg when using guest PEBS
2023-05-28 07:37:23 -04:00
Linus Torvalds
abbf7fa15b Merge tag 'objtool-urgent-2023-05-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull unwinder fixes from Thomas Gleixner:
 "A set of unwinder and tooling fixes:

   - Ensure that the stack pointer on x86 is aligned again so that the
     unwinder does not read past the end of the stack

   - Discard .note.gnu.property section which has a pointlessly
     different alignment than the other note sections. That confuses
     tooling of all sorts including readelf, libbpf and pahole"

* tag 'objtool-urgent-2023-05-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/show_trace_log_lvl: Ensure stack pointer is aligned, again
  vmlinux.lds.h: Discard .note.gnu.property section
2023-05-28 07:33:29 -04:00