10 Jun, 2023
40 commits
-
Now in ocfs2_local_free_info(), it returns 0 even if it actually fails.
Though it doesn't cause any real problem since the only caller
dquot_disable() ignores the return value, we'd better return correct as it
is.Link: https://lkml.kernel.org/r/20230528132033.217664-1-joseph.qi@linux.alibaba.com
Signed-off-by: Joseph Qi
Cc: Mark Fasheh
Cc: Joel Becker
Cc: Junxiao Bi
Cc: Joseph Qi
Cc: Changwei Ge
Cc: Gang He
Cc: Jun Piao
Signed-off-by: Andrew Morton -
Avoid calculating array size twice in kexec_purgatory_setup_sechdrs().
Once using array_size(), and once open-coded.Flagged by Coccinelle:
.../kexec_file.c:881:8-25: WARNING: array_size is already used (line 877) to compute the same size
No functional change intended.
Compile tested only.Link: https://lkml.kernel.org/r/20230525-kexec-array_size-v1-1-8b4bf4f7500a@kernel.org
Signed-off-by: Simon Horman
Acked-by: Baoquan He
Cc: Eric W. Biederman
Cc: Zhen Lei
Signed-off-by: Andrew Morton -
mult_frac() evaluates _all_ arguments multiple times in the body.
Clarify comment while I'm at it.
Link: https://lkml.kernel.org/r/f9f9fdbb-ec8e-4f5e-a998-2a58627a1a43@p183
Signed-off-by: Alexey Dobriyan
Signed-off-by: Andrew Morton -
With the recent feature added to enable perf events to use pseudo NMIs as
interrupts on platforms which support GICv3 or later, its now been
possible to enable hard lockup detector (or NMI watchdog) on arm64
platforms. So enable corresponding support.One thing to note here is that normally lockup detector is initialized
just after the early initcalls but PMU on arm64 comes up much later as
device_initcall(). To cope with that, override
arch_perf_nmi_is_available() to let the watchdog framework know PMU not
ready, and inform the framework to re-initialize lockup detection once PMU
has been initialized.[dianders@chromium.org: only HAVE_HARDLOCKUP_DETECTOR_PERF if the PMU config is enabled]
Link: https://lkml.kernel.org/r/20230523073952.1.I60217a63acc35621e13f10be16c0cd7c363caf8c@changeid
Link: https://lkml.kernel.org/r/20230519101840.v5.18.Ia44852044cdcb074f387e80df6b45e892965d4a1@changeid
Co-developed-by: Sumit Garg
Signed-off-by: Sumit Garg
Co-developed-by: Pingfan Liu
Signed-off-by: Pingfan Liu
Signed-off-by: Lecopzer Chen
Signed-off-by: Douglas Anderson
Cc: Andi Kleen
Cc: Catalin Marinas
Cc: Chen-Yu Tsai
Cc: Christophe Leroy
Cc: Colin Cross
Cc: Daniel Thompson
Cc: "David S. Miller"
Cc: Guenter Roeck
Cc: Ian Rogers
Cc: Marc Zyngier
Cc: Mark Rutland
Cc: Masayoshi Mizuma
Cc: Matthias Kaehlcke
Cc: Michael Ellerman
Cc: Nicholas Piggin
Cc: Petr Mladek
Cc: Randy Dunlap
Cc: "Ravi V. Shankar"
Cc: Ricardo Neri
Cc: Stephane Eranian
Cc: Stephen Boyd
Cc: Tzung-Bi Shih
Cc: Will Deacon
Signed-off-by: Andrew Morton -
Set safe maximum CPU frequency to 5 GHz in case a particular platform
doesn't implement cpufreq driver. Although, architecture doesn't put any
restrictions on maximum frequency but 5 GHz seems to be safe maximum given
the available Arm CPUs in the market which are clocked much less than 5
GHz.On the other hand, we can't make it much higher as it would lead to a
large hard-lockup detection timeout on parts which are running slower (eg.
1GHz on Developerbox) and doesn't possess a cpufreq driver.Link: https://lkml.kernel.org/r/20230519101840.v5.17.Ia9d02578e89c3f44d3cb12eec8b0176603c8ab2f@changeid
Co-developed-by: Sumit Garg
Signed-off-by: Sumit Garg
Co-developed-by: Pingfan Liu
Signed-off-by: Pingfan Liu
Signed-off-by: Lecopzer Chen
Signed-off-by: Douglas Anderson
Cc: Andi Kleen
Cc: Catalin Marinas
Cc: Chen-Yu Tsai
Cc: Christophe Leroy
Cc: Colin Cross
Cc: Daniel Thompson
Cc: "David S. Miller"
Cc: Guenter Roeck
Cc: Ian Rogers
Cc: Marc Zyngier
Cc: Mark Rutland
Cc: Masayoshi Mizuma
Cc: Matthias Kaehlcke
Cc: Michael Ellerman
Cc: Nicholas Piggin
Cc: Petr Mladek
Cc: Randy Dunlap
Cc: "Ravi V. Shankar"
Cc: Ricardo Neri
Cc: Stephane Eranian
Cc: Stephen Boyd
Cc: Tzung-Bi Shih
Cc: Will Deacon
Signed-off-by: Andrew Morton -
When lockup_detector_init()->watchdog_hardlockup_probe(), PMU may be not
ready yet. E.g. on arm64, PMU is not ready until
device_initcall(armv8_pmu_driver_init). And it is deeply integrated with
the driver model and cpuhp. Hence it is hard to push this initialization
before smp_init().But it is easy to take an opposite approach and try to initialize the
watchdog once again later. The delayed probe is called using workqueues.
It need to allocate memory and must be proceed in a normal context. The
delayed probe is able to use if watchdog_hardlockup_probe() returns
non-zero which means the return code returned when PMU is not ready yet.Provide an API - lockup_detector_retry_init() for anyone who needs to
delayed init lockup detector if they had ever failed at
lockup_detector_init().The original assumption is: nobody should use delayed probe after
lockup_detector_check() which has __init attribute. That is, anyone uses
this API must call between lockup_detector_init() and
lockup_detector_check(), and the caller must have __init attributeLink: https://lkml.kernel.org/r/20230519101840.v5.16.If4ad5dd5d09fb1309cebf8bcead4b6a5a7758ca7@changeid
Reviewed-by: Petr Mladek
Co-developed-by: Pingfan Liu
Signed-off-by: Pingfan Liu
Signed-off-by: Lecopzer Chen
Signed-off-by: Douglas Anderson
Suggested-by: Petr Mladek
Cc: Andi Kleen
Cc: Catalin Marinas
Cc: Chen-Yu Tsai
Cc: Christophe Leroy
Cc: Colin Cross
Cc: Daniel Thompson
Cc: "David S. Miller"
Cc: Guenter Roeck
Cc: Ian Rogers
Cc: Marc Zyngier
Cc: Mark Rutland
Cc: Masayoshi Mizuma
Cc: Matthias Kaehlcke
Cc: Michael Ellerman
Cc: Nicholas Piggin
Cc: Randy Dunlap
Cc: "Ravi V. Shankar"
Cc: Ricardo Neri
Cc: Stephane Eranian
Cc: Stephen Boyd
Cc: Sumit Garg
Cc: Tzung-Bi Shih
Cc: Will Deacon
Signed-off-by: Andrew Morton -
On arm64, NMI support needs to be detected at runtime. Add a weak
function to the perf hardlockup detector so that an architecture can
implement it to detect whether NMIs are available.Link: https://lkml.kernel.org/r/20230519101840.v5.15.Ic55cb6f90ef5967d8aaa2b503a4e67c753f64d3a@changeid
Signed-off-by: Douglas Anderson
Cc: Andi Kleen
Cc: Catalin Marinas
Cc: Chen-Yu Tsai
Cc: Christophe Leroy
Cc: Colin Cross
Cc: Daniel Thompson
Cc: "David S. Miller"
Cc: Guenter Roeck
Cc: Ian Rogers
Cc: Lecopzer Chen
Cc: Marc Zyngier
Cc: Mark Rutland
Cc: Masayoshi Mizuma
Cc: Matthias Kaehlcke
Cc: Michael Ellerman
Cc: Nicholas Piggin
Cc: Petr Mladek
Cc: Pingfan Liu
Cc: Randy Dunlap
Cc: "Ravi V. Shankar"
Cc: Ricardo Neri
Cc: Stephane Eranian
Cc: Stephen Boyd
Cc: Sumit Garg
Cc: Tzung-Bi Shih
Cc: Will Deacon
Signed-off-by: Andrew Morton -
Implement a hardlockup detector that doesn't doesn't need any extra
arch-specific support code to detect lockups. Instead of using something
arch-specific we will use the buddy system, where each CPU watches out for
another one. Specifically, each CPU will use its softlockup hrtimer to
check that the next CPU is processing hrtimer interrupts by verifying that
a counter is increasing.NOTE: unlike the other hard lockup detectors, the buddy one can't easily
show what's happening on the CPU that locked up just by doing a simple
backtrace. It relies on some other mechanism in the system to get
information about the locked up CPUs. This could be support for NMI
backtraces like [1], it could be a mechanism for printing the PC of locked
CPUs at panic time like [2] / [3], or it could be something else. Even
though that means we still rely on arch-specific code, this arch-specific
code seems to often be implemented even on architectures that don't have a
hardlockup detector.This style of hardlockup detector originated in some downstream Android
trees and has been rebased on / carried in ChromeOS trees for quite a long
time for use on arm and arm64 boards. Historically on these boards we've
leveraged mechanism [2] / [3] to get information about hung CPUs, but we
could move to [1].Although the original motivation for the buddy system was for use on
systems without an arch-specific hardlockup detector, it can still be
useful to use even on systems that _do_ have an arch-specific hardlockup
detector. On x86, for instance, there is a 24-part patch series [4] in
progress switching the arch-specific hard lockup detector from a scarce
perf counter to a less-scarce hardware resource. Potentially the buddy
system could be a simpler alternative to free up the perf counter but
still get hard lockup detection.Overall, pros (+) and cons (-) of the buddy system compared to an
arch-specific hardlockup detector (which might be implemented using
perf):
+ The buddy system is usable on systems that don't have an
arch-specific hardlockup detector, like arm32 and arm64 (though it's
being worked on for arm64 [5]).
+ The buddy system may free up scarce hardware resources.
+ If a CPU totally goes out to lunch (can't process NMIs) the buddy
system could still detect the problem (though it would be unlikely
to be able to get a stack trace).
+ The buddy system uses the same timer function to pet the hardlockup
detector on the running CPU as it uses to detect hardlockups on
other CPUs. Compared to other hardlockup detectors, this means it
generates fewer interrupts and thus is likely better able to let
CPUs stay idle longer.
- If all CPUs are hard locked up at the same time the buddy system
can't detect it.
- If we don't have SMP we can't use the buddy system.
- The buddy system needs an arch-specific mechanism (possibly NMI
backtrace) to get info about the locked up CPU.[1] https://lore.kernel.org/r/20230419225604.21204-1-dianders@chromium.org
[2] https://issuetracker.google.com/172213129
[3] https://docs.kernel.org/trace/coresight/coresight-cpu-debug.html
[4] https://lore.kernel.org/lkml/20230301234753.28582-1-ricardo.neri-calderon@linux.intel.com/
[5] https://lore.kernel.org/linux-arm-kernel/20220903093415.15850-1-lecopzer.chen@mediatek.com/Link: https://lkml.kernel.org/r/20230519101840.v5.14.I6bf789d21d0c3d75d382e7e51a804a7a51315f2c@changeid
Signed-off-by: Colin Cross
Signed-off-by: Matthias Kaehlcke
Signed-off-by: Guenter Roeck
Signed-off-by: Tzung-Bi Shih
Signed-off-by: Douglas Anderson
Cc: Andi Kleen
Cc: Catalin Marinas
Cc: Chen-Yu Tsai
Cc: Christophe Leroy
Cc: Daniel Thompson
Cc: "David S. Miller"
Cc: Ian Rogers
Cc: Marc Zyngier
Cc: Mark Rutland
Cc: Masayoshi Mizuma
Cc: Michael Ellerman
Cc: Nicholas Piggin
Cc: Petr Mladek
Cc: Pingfan Liu
Cc: Randy Dunlap
Cc: "Ravi V. Shankar"
Cc: Ricardo Neri
Cc: Stephane Eranian
Cc: Stephen Boyd
Cc: Sumit Garg
Cc: Will Deacon
Signed-off-by: Andrew Morton -
The fact that there watchdog_hardlockup_enable(),
watchdog_hardlockup_disable(), and watchdog_hardlockup_probe() are
declared __weak means that the configured hardlockup detector can define
non-weak versions of those functions if it needs to. Instead of doing
this, the perf hardlockup detector hooked itself into the default __weak
implementation, which was a bit awkward. Clean this up.From comments, it looks as if the original design was done because the
__weak function were expected to implemented by the architecture and not
by the configured hardlockup detector. This got awkward when we tried to
add the buddy lockup detector which was not arch-specific but wanted to
hook into those same functions.This is not expected to have any functional impact.
Link: https://lkml.kernel.org/r/20230519101840.v5.13.I847d9ec852449350997ba00401d2462a9cb4302b@changeid
Signed-off-by: Douglas Anderson
Reviewed-by: Petr Mladek
Cc: Andi Kleen
Cc: Catalin Marinas
Cc: Chen-Yu Tsai
Cc: Christophe Leroy
Cc: Colin Cross
Cc: Daniel Thompson
Cc: "David S. Miller"
Cc: Guenter Roeck
Cc: Ian Rogers
Cc: Lecopzer Chen
Cc: Marc Zyngier
Cc: Mark Rutland
Cc: Masayoshi Mizuma
Cc: Matthias Kaehlcke
Cc: Michael Ellerman
Cc: Nicholas Piggin
Cc: Pingfan Liu
Cc: Randy Dunlap
Cc: "Ravi V. Shankar"
Cc: Ricardo Neri
Cc: Stephane Eranian
Cc: Stephen Boyd
Cc: Sumit Garg
Cc: Tzung-Bi Shih
Cc: Will Deacon
Signed-off-by: Andrew Morton -
Do a search and replace of:
- NMI_WATCHDOG_ENABLED => WATCHDOG_HARDLOCKUP_ENABLED
- SOFT_WATCHDOG_ENABLED => WATCHDOG_SOFTOCKUP_ENABLED
- watchdog_nmi_ => watchdog_hardlockup_
- nmi_watchdog_available => watchdog_hardlockup_available
- nmi_watchdog_user_enabled => watchdog_hardlockup_user_enabled
- soft_watchdog_user_enabled => watchdog_softlockup_user_enabled
- NMI_WATCHDOG_DEFAULT => WATCHDOG_HARDLOCKUP_DEFAULTThen update a few comments near where names were changed.
This is specifically to make it less confusing when we want to introduce
the buddy hardlockup detector, which isn't using NMIs. As part of this,
we sanitized a few names for consistency.[trix@redhat.com: make variables static]
Link: https://lkml.kernel.org/r/20230525162822.1.I0fb41d138d158c9230573eaa37dc56afa2fb14ee@changeid
Link: https://lkml.kernel.org/r/20230519101840.v5.12.I91f7277bab4bf8c0cb238732ed92e7ce7bbd71a6@changeid
Signed-off-by: Douglas Anderson
Signed-off-by: Tom Rix
Reviewed-by: Tom Rix
Cc: Andi Kleen
Cc: Catalin Marinas
Cc: Chen-Yu Tsai
Cc: Christophe Leroy
Cc: Colin Cross
Cc: Daniel Thompson
Cc: "David S. Miller"
Cc: Guenter Roeck
Cc: Ian Rogers
Cc: Lecopzer Chen
Cc: Marc Zyngier
Cc: Mark Rutland
Cc: Masayoshi Mizuma
Cc: Matthias Kaehlcke
Cc: Michael Ellerman
Cc: Nicholas Piggin
Cc: Petr Mladek
Cc: Pingfan Liu
Cc: Randy Dunlap
Cc: "Ravi V. Shankar"
Cc: Ricardo Neri
Cc: Stephane Eranian
Cc: Stephen Boyd
Cc: Sumit Garg
Cc: Tzung-Bi Shih
Cc: Will Deacon
Signed-off-by: Andrew Morton -
In preparation for the buddy hardlockup detector, which wants the same
petting logic as the current perf hardlockup detector, move the code to
watchdog.c. While doing this, rename the global variable to match others
nearby. As part of this change we have to change the code to account for
the fact that the CPU we're running on might be different than the one
we're checking.Currently the code in watchdog.c is guarded by
CONFIG_HARDLOCKUP_DETECTOR_PERF, which makes this change seem silly.
However, a future patch will change this.Link: https://lkml.kernel.org/r/20230519101840.v5.11.I00dfd6386ee00da25bf26d140559a41339b53e57@changeid
Signed-off-by: Douglas Anderson
Cc: Andi Kleen
Cc: Catalin Marinas
Cc: Chen-Yu Tsai
Cc: Christophe Leroy
Cc: Colin Cross
Cc: Daniel Thompson
Cc: "David S. Miller"
Cc: Guenter Roeck
Cc: Ian Rogers
Cc: Lecopzer Chen
Cc: Marc Zyngier
Cc: Mark Rutland
Cc: Masayoshi Mizuma
Cc: Matthias Kaehlcke
Cc: Michael Ellerman
Cc: Nicholas Piggin
Cc: Petr Mladek
Cc: Pingfan Liu
Cc: Randy Dunlap
Cc: "Ravi V. Shankar"
Cc: Ricardo Neri
Cc: Stephane Eranian
Cc: Stephen Boyd
Cc: Sumit Garg
Cc: Tzung-Bi Shih
Cc: Will Deacon
Signed-off-by: Andrew Morton -
In preparation for the buddy hardlockup detector where the CPU checking
for lockup might not be the currently running CPU, add a "cpu" parameter
to watchdog_hardlockup_check().As part of this change, make hrtimer_interrupts an atomic_t since now the
CPU incrementing the value and the CPU reading the value might be
different. Technially this could also be done with just READ_ONCE and
WRITE_ONCE, but atomic_t feels a little cleaner in this case.While hrtimer_interrupts is made atomic_t, we change
hrtimer_interrupts_saved from "unsigned long" to "int". The "int" is
needed to match the data type backing atomic_t for hrtimer_interrupts.
Even if this changes us from 64-bits to 32-bits (which I don't think is
true for most compilers), it doesn't really matter. All we ever do is
increment it every few seconds and compare it to an old value so 32-bits
is fine (even 16-bits would be). The "signed" vs "unsigned" also doesn't
matter for simple equality comparisons.hrtimer_interrupts_saved is _not_ switched to atomic_t nor even accessed
with READ_ONCE / WRITE_ONCE. The hrtimer_interrupts_saved is always
consistently accessed with the same CPU. NOTE: with the upcoming "buddy"
detector there is one special case. When a CPU goes offline/online then
we can change which CPU is the one to consistently access a given instance
of hrtimer_interrupts_saved. We still can't end up with a partially
updated hrtimer_interrupts_saved, however, because we end up petting all
affected CPUs to make sure the new and old CPU can't end up somehow
read/write hrtimer_interrupts_saved at the same time.Link: https://lkml.kernel.org/r/20230519101840.v5.10.I3a7d4dd8c23ac30ee0b607d77feb6646b64825c0@changeid
Signed-off-by: Douglas Anderson
Cc: Andi Kleen
Cc: Catalin Marinas
Cc: Chen-Yu Tsai
Cc: Christophe Leroy
Cc: Colin Cross
Cc: Daniel Thompson
Cc: "David S. Miller"
Cc: Guenter Roeck
Cc: Ian Rogers
Cc: Lecopzer Chen
Cc: Marc Zyngier
Cc: Mark Rutland
Cc: Masayoshi Mizuma
Cc: Matthias Kaehlcke
Cc: Michael Ellerman
Cc: Nicholas Piggin
Cc: Petr Mladek
Cc: Pingfan Liu
Cc: Randy Dunlap
Cc: "Ravi V. Shankar"
Cc: Ricardo Neri
Cc: Stephane Eranian
Cc: Stephen Boyd
Cc: Sumit Garg
Cc: Tzung-Bi Shih
Cc: Will Deacon
Signed-off-by: Andrew Morton -
These are tiny style changes:
- Add a blank line before a "return".
- Renames two globals to use the "watchdog_hardlockup" prefix.
- Store processor id in "unsigned int" rather than "int".
- Minor comment rewording.
- Use "else" rather than extra returns since it seemed more symmetric.Link: https://lkml.kernel.org/r/20230519101840.v5.9.I818492c326b632560b09f20d2608455ecf9d3650@changeid
Reviewed-by: Petr Mladek
Signed-off-by: Douglas Anderson
Cc: Andi Kleen
Cc: Catalin Marinas
Cc: Chen-Yu Tsai
Cc: Christophe Leroy
Cc: Colin Cross
Cc: Daniel Thompson
Cc: "David S. Miller"
Cc: Guenter Roeck
Cc: Ian Rogers
Cc: Lecopzer Chen
Cc: Marc Zyngier
Cc: Mark Rutland
Cc: Masayoshi Mizuma
Cc: Matthias Kaehlcke
Cc: Michael Ellerman
Cc: Nicholas Piggin
Cc: Pingfan Liu
Cc: Randy Dunlap
Cc: "Ravi V. Shankar"
Cc: Ricardo Neri
Cc: Stephane Eranian
Cc: Stephen Boyd
Cc: Sumit Garg
Cc: Tzung-Bi Shih
Cc: Will Deacon
Signed-off-by: Andrew Morton -
The perf hardlockup detector works by looking at interrupt counts and
seeing if they change from run to run. The interrupt counts are managed
by the common watchdog code via its watchdog_timer_fn().Currently the API between the perf detector and the common code is a
function: is_hardlockup(). When the hard lockup detector sees that
function return true then it handles printing out debug info and inducing
a panic if necessary.Let's change the API a little bit in preparation for the buddy hardlockup
detector. The buddy hardlockup detector wants to print nearly the same
debug info and have nearly the same panic behavior. That means we want to
move all that code to the common file. For now, the code in the common
file will only be there if the perf hardlockup detector is enabled, but
eventually it will be selected by a common config.Right now, this _just_ moves the code from the perf detector file to the
common file and changes the names. It doesn't make the changes that the
buddy hardlockup detector will need and doesn't do any style cleanups. A
future patch will do cleanup to make it more obvious what changed.With the above, we no longer have any callers of is_hardlockup() outside
of the "watchdog.c" file, so we can remove it from the header, make it
static, and move it to the same "#ifdef" block as our new
watchdog_hardlockup_check(). While doing this, it can be noted that even
if no hardlockup detectors were configured the existing code used to still
have the code for counting/checking "hrtimer_interrupts" even if the perf
hardlockup detector wasn't configured. We didn't need to do that, so move
all the "hrtimer_interrupts" counting to only be there if the perf
hardlockup detector is configured as well.This change is expected to be a no-op.
Link: https://lkml.kernel.org/r/20230519101840.v5.8.Id4133d3183e798122dc3b6205e7852601f289071@changeid
Signed-off-by: Douglas Anderson
Reviewed-by: Petr Mladek
Cc: Andi Kleen
Cc: Catalin Marinas
Cc: Chen-Yu Tsai
Cc: Christophe Leroy
Cc: Colin Cross
Cc: Daniel Thompson
Cc: "David S. Miller"
Cc: Guenter Roeck
Cc: Ian Rogers
Cc: Lecopzer Chen
Cc: Marc Zyngier
Cc: Mark Rutland
Cc: Masayoshi Mizuma
Cc: Matthias Kaehlcke
Cc: Michael Ellerman
Cc: Nicholas Piggin
Cc: Pingfan Liu
Cc: Randy Dunlap
Cc: "Ravi V. Shankar"
Cc: Ricardo Neri
Cc: Stephane Eranian
Cc: Stephen Boyd
Cc: Sumit Garg
Cc: Tzung-Bi Shih
Cc: Will Deacon
Signed-off-by: Andrew Morton -
The code currently in "watchdog_hld.c" is for detecting hardlockups using
perf, as evidenced by the line in the Makefile that only compiles this
file if CONFIG_HARDLOCKUP_DETECTOR_PERF is defined. Rename the file to
prepare for the buddy hardlockup detector, which doesn't use perf.It could be argued that the new name makes it less obvious that this is a
hardlockup detector. While true, it's not hard to remember that the
"perf" detector is always a hardlockup detector and it's nice not to have
names that are too convoluted.Link: https://lkml.kernel.org/r/20230519101840.v5.7.Ice803cb078d0e15fb2cbf49132f096ee2bd4199d@changeid
Signed-off-by: Douglas Anderson
Acked-by: Nicholas Piggin
Reviewed-by: Petr Mladek
Cc: Andi Kleen
Cc: Catalin Marinas
Cc: Chen-Yu Tsai
Cc: Christophe Leroy
Cc: Colin Cross
Cc: Daniel Thompson
Cc: "David S. Miller"
Cc: Guenter Roeck
Cc: Ian Rogers
Cc: Lecopzer Chen
Cc: Marc Zyngier
Cc: Mark Rutland
Cc: Masayoshi Mizuma
Cc: Matthias Kaehlcke
Cc: Michael Ellerman
Cc: Pingfan Liu
Cc: Randy Dunlap
Cc: "Ravi V. Shankar"
Cc: Ricardo Neri
Cc: Stephane Eranian
Cc: Stephen Boyd
Cc: Sumit Garg
Cc: Tzung-Bi Shih
Cc: Will Deacon
Signed-off-by: Andrew Morton -
In preparation for the buddy hardlockup detector, add comments to
touch_nmi_watchdog() to make it obvious that it touches the configured
hardlockup detector regardless of whether it's backed by an NMI. Also
note that arch_touch_nmi_watchdog() may not be architecture-specific.Ideally, we'd like to rename these functions but that is a fairly
disruptive change touching a lot of drivers. After discussion [1] the
plan is to defer this until a good time.[1] https://lore.kernel.org/r/ZFy0TX1tfhlH8gxj@alley
[akpm@linux-foundation.org: comment changes, per Petr]
Link: https://lkml.kernel.org/r/ZGyONWPXpE1DcxA5@alley
Link: https://lkml.kernel.org/r/20230519101840.v5.6.I4e47cbfa1bb2ebbcdb5ca16817aa2887f15dc82c@changeid
Signed-off-by: Douglas Anderson
Reviewed-by: Petr Mladek
Cc: Andi Kleen
Cc: Catalin Marinas
Cc: Chen-Yu Tsai
Cc: Christophe Leroy
Cc: Colin Cross
Cc: Daniel Thompson
Cc: "David S. Miller"
Cc: Guenter Roeck
Cc: Ian Rogers
Cc: Lecopzer Chen
Cc: Marc Zyngier
Cc: Mark Rutland
Cc: Masayoshi Mizuma
Cc: Matthias Kaehlcke
Cc: Michael Ellerman
Cc: Nicholas Piggin
Cc: Petr Mladek
Cc: Pingfan Liu
Cc: Randy Dunlap
Cc: "Ravi V. Shankar"
Cc: Ricardo Neri
Cc: Stephane Eranian
Cc: Stephen Boyd
Cc: Sumit Garg
Cc: Tzung-Bi Shih
Cc: Will Deacon
Signed-off-by: Andrew Morton -
hardlockup_detector_event_create() should create perf_event on the current
CPU. Preemption could not get disabled because
perf_event_create_kernel_counter() allocates memory. Instead, the CPU
locality is achieved by processing the code in a per-CPU bound kthread.Add a check to prevent mistakes when calling the code in another code
path.Link: https://lkml.kernel.org/r/20230519101840.v5.5.I654063e53782b11d53e736a8ad4897ffd207406a@changeid
Signed-off-by: Pingfan Liu
Co-developed-by: Lecopzer Chen
Signed-off-by: Lecopzer Chen
Signed-off-by: Douglas Anderson
Reviewed-by: Petr Mladek
Cc: Andi Kleen
Cc: Catalin Marinas
Cc: Chen-Yu Tsai
Cc: Christophe Leroy
Cc: Colin Cross
Cc: Daniel Thompson
Cc: "David S. Miller"
Cc: Guenter Roeck
Cc: Ian Rogers
Cc: Marc Zyngier
Cc: Mark Rutland
Cc: Masayoshi Mizuma
Cc: Matthias Kaehlcke
Cc: Michael Ellerman
Cc: Nicholas Piggin
Cc: Randy Dunlap
Cc: "Ravi V. Shankar"
Cc: Ricardo Neri
Cc: Stephane Eranian
Cc: Stephen Boyd
Cc: Sumit Garg
Cc: Tzung-Bi Shih
Cc: Will Deacon
Signed-off-by: Andrew Morton -
Nobody cares about the return value of watchdog_nmi_enable(), changing its
prototype to void.Link: https://lkml.kernel.org/r/20230519101840.v5.4.Ic3a19b592eb1ac4c6f6eade44ffd943e8637b6e5@changeid
Signed-off-by: Pingfan Liu
Signed-off-by: Lecopzer Chen
Signed-off-by: Douglas Anderson
Reviewed-by: Petr Mladek
Acked-by: Nicholas Piggin
Cc: Andi Kleen
Cc: Catalin Marinas
Cc: Chen-Yu Tsai
Cc: Christophe Leroy
Cc: Colin Cross
Cc: Daniel Thompson
Cc: "David S. Miller"
Cc: Guenter Roeck
Cc: Ian Rogers
Cc: Marc Zyngier
Cc: Mark Rutland
Cc: Masayoshi Mizuma
Cc: Matthias Kaehlcke
Cc: Michael Ellerman
Cc: Randy Dunlap
Cc: "Ravi V. Shankar"
Cc: Ricardo Neri
Cc: Stephane Eranian
Cc: Stephen Boyd
Cc: Sumit Garg
Cc: Tzung-Bi Shih
Cc: Will Deacon
Signed-off-by: Andrew Morton -
No reference to WATCHDOG_DEFAULT, remove it.
Link: https://lkml.kernel.org/r/20230519101840.v5.3.I6a729209a1320e0ad212176e250ff945b8f91b2a@changeid
Signed-off-by: Pingfan Liu
Signed-off-by: Lecopzer Chen
Signed-off-by: Douglas Anderson
Reviewed-by: Petr Mladek
Cc: Andi Kleen
Cc: Catalin Marinas
Cc: Chen-Yu Tsai
Cc: Christophe Leroy
Cc: Colin Cross
Cc: Daniel Thompson
Cc: "David S. Miller"
Cc: Guenter Roeck
Cc: Ian Rogers
Cc: Marc Zyngier
Cc: Mark Rutland
Cc: Masayoshi Mizuma
Cc: Matthias Kaehlcke
Cc: Michael Ellerman
Cc: Nicholas Piggin
Cc: Randy Dunlap
Cc: "Ravi V. Shankar"
Cc: Ricardo Neri
Cc: Stephane Eranian
Cc: Stephen Boyd
Cc: Sumit Garg
Cc: Tzung-Bi Shih
Cc: Will Deacon
Signed-off-by: Andrew Morton -
Currently, in the watchdog_overflow_callback() we first check to see if
the watchdog had been touched and _then_ we handle the workaround for
turbo mode. This order should be reversed.Specifically, "touching" the hardlockup detector's watchdog should avoid
lockups being detected for one period that should be roughly the same
regardless of whether we're running turbo or not. That means that we
should do the extra accounting for turbo _before_ we look at (and clear)
the global indicating that we've been touched.NOTE: this fix is made based on code inspection. I am not aware of any
reports where the old code would have generated false positives. That
being said, this order seems more correct and also makes it easier down
the line to share code with the "buddy" hardlockup detector.Link: https://lkml.kernel.org/r/20230519101840.v5.2.I843b0d1de3e096ba111a179f3adb16d576bef5c7@changeid
Fixes: 7edaeb6841df ("kernel/watchdog: Prevent false positives with turbo modes")
Signed-off-by: Douglas Anderson
Cc: Andi Kleen
Cc: Catalin Marinas
Cc: Chen-Yu Tsai
Cc: Christophe Leroy
Cc: Colin Cross
Cc: Daniel Thompson
Cc: "David S. Miller"
Cc: Guenter Roeck
Cc: Ian Rogers
Cc: Lecopzer Chen
Cc: Marc Zyngier
Cc: Mark Rutland
Cc: Masayoshi Mizuma
Cc: Matthias Kaehlcke
Cc: Michael Ellerman
Cc: Nicholas Piggin
Cc: Petr Mladek
Cc: Pingfan Liu
Cc: Randy Dunlap
Cc: "Ravi V. Shankar"
Cc: Ricardo Neri
Cc: Stephane Eranian
Cc: Stephen Boyd
Cc: Sumit Garg
Cc: Tzung-Bi Shih
Cc: Will Deacon
Signed-off-by: Andrew Morton -
Patch series "watchdog/hardlockup: Add the buddy hardlockup detector", v5.
This patch series adds the "buddy" hardlockup detector. In brief, the
buddy hardlockup detector can detect hardlockups without arch-level
support by having CPUs checkup on a "buddy" CPU periodically.Given the new design of this patch series, testing all combinations is
fairly difficult. I've attempted to make sure that all combinations of
CONFIG_ options are good, but it wouldn't surprise me if I missed
something. I apologize in advance and I'll do my best to fix any
problems that are found.This patch (of 18):
The real watchdog_update_hrtimer_threshold() is defined in
kernel/watchdog_hld.c. That file is included if
CONFIG_HARDLOCKUP_DETECTOR_PERF and the function is defined in that file
if CONFIG_HARDLOCKUP_CHECK_TIMESTAMP.The dummy version of the function in "nmi.h" didn't get that quite right.
While this doesn't appear to be a huge deal, it's nice to make it
consistent.It doesn't break builds because CHECK_TIMESTAMP is only defined by x86 so
others don't get a double definition, and x86 uses perf lockup detector,
so it gets the out of line version.Link: https://lkml.kernel.org/r/20230519101840.v5.18.Ia44852044cdcb074f387e80df6b45e892965d4a1@changeid
Link: https://lkml.kernel.org/r/20230519101840.v5.1.I8cbb2f4fa740528fcfade4f5439b6cdcdd059251@changeid
Fixes: 7edaeb6841df ("kernel/watchdog: Prevent false positives with turbo modes")
Signed-off-by: Douglas Anderson
Reviewed-by: Nicholas Piggin
Reviewed-by: Petr Mladek
Cc: Andi Kleen
Cc: Catalin Marinas
Cc: Chen-Yu Tsai
Cc: Christophe Leroy
Cc: Daniel Thompson
Cc: "David S. Miller"
Cc: Guenter Roeck
Cc: Ian Rogers
Cc: Lecopzer Chen
Cc: Marc Zyngier
Cc: Mark Rutland
Cc: Masayoshi Mizuma
Cc: Matthias Kaehlcke
Cc: Michael Ellerman
Cc: Pingfan Liu
Cc: Randy Dunlap
Cc: "Ravi V. Shankar"
Cc: Ricardo Neri
Cc: Stephane Eranian
Cc: Stephen Boyd
Cc: Sumit Garg
Cc: Tzung-Bi Shih
Cc: Will Deacon
Cc: Colin Cross
Signed-off-by: Andrew Morton -
The entry points for the decompressor don't always have a prototype
included in the .c file:lib/decompress_inflate.c:42:17: error: no previous prototype for '__gunzip' [-Werror=missing-prototypes]
lib/decompress_unxz.c:251:17: error: no previous prototype for 'unxz' [-Werror=missing-prototypes]
lib/decompress_unzstd.c:331:17: error: no previous prototype for 'unzstd' [-Werror=missing-prototypes]Include the correct headers for unxz and unzstd, and mark the inflate
function above as unconditionally 'static' to avoid these warnings.Link: https://lkml.kernel.org/r/20230517131936.936840-1-arnd@kernel.org
Signed-off-by: Arnd Bergmann
Cc: Nick Terrell
Signed-off-by: Andrew Morton -
Booting with the QEMU command line:
"qemu-system-x86_64 -append root=/dev/vda rootfstype=ext4 ..."
will panic if ext4 is not builtin and a request to load the ext4 module
fails.[ 1.729006] VFS: Cannot open root device "vda" or unknown-block(253,0): error -19
[ 1.730603] Please append a correct "root=" boot option; here are the available partitions:
[ 1.732323] fd00 256000 vda
[ 1.732329] driver: virtio_blk
[ 1.734194] Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(253,0)
[ 1.734771] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 6.4.0-rc2+ #53
[ 1.735194] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.10.2-1ubuntu1 04/01/2014
[ 1.735772] Call Trace:
[ 1.735950]
[ 1.736113] dump_stack_lvl+0x32/0x50
[ 1.736367] panic+0x108/0x310
[ 1.736570] mount_block_root+0x161/0x310
[ 1.736849] ? rdinit_setup+0x40/0x40
[ 1.737088] prepare_namespace+0x10c/0x180
[ 1.737393] kernel_init_freeable+0x354/0x450
[ 1.737707] ? rest_init+0xd0/0xd0
[ 1.737945] kernel_init+0x16/0x130
[ 1.738196] ret_from_fork+0x1f/0x30As a hint, print all the bdev fstypes which are available.
[akpm@linux-foundation.org: fix spelling in printk message]
Link: https://lkml.kernel.org/r/20230518035321.1672-1-angus.chen@jaguarmicro.com
Signed-off-by: Angus Chen
Acked-by: Nick Desaulniers
Cc: Masahiro Yamada
Cc: Mike Rapoport (IBM)
Cc: Paul E. McKenney
Cc: Peter Zijlstra
Cc: Vlastimil Babka
Cc: Al Viro
Signed-off-by: Andrew Morton -
A number of internal functions in kcov are only called from generated code
and don't technically need a declaration, but 'make W=1' warns about
global symbols without a prototype:kernel/kcov.c:199:14: error: no previous prototype for '__sanitizer_cov_trace_pc' [-Werror=missing-prototypes]
kernel/kcov.c:264:14: error: no previous prototype for '__sanitizer_cov_trace_cmp1' [-Werror=missing-prototypes]
kernel/kcov.c:270:14: error: no previous prototype for '__sanitizer_cov_trace_cmp2' [-Werror=missing-prototypes]
kernel/kcov.c:276:14: error: no previous prototype for '__sanitizer_cov_trace_cmp4' [-Werror=missing-prototypes]
kernel/kcov.c:282:14: error: no previous prototype for '__sanitizer_cov_trace_cmp8' [-Werror=missing-prototypes]
kernel/kcov.c:288:14: error: no previous prototype for '__sanitizer_cov_trace_const_cmp1' [-Werror=missing-prototypes]
kernel/kcov.c:295:14: error: no previous prototype for '__sanitizer_cov_trace_const_cmp2' [-Werror=missing-prototypes]
kernel/kcov.c:302:14: error: no previous prototype for '__sanitizer_cov_trace_const_cmp4' [-Werror=missing-prototypes]
kernel/kcov.c:309:14: error: no previous prototype for '__sanitizer_cov_trace_const_cmp8' [-Werror=missing-prototypes]
kernel/kcov.c:316:14: error: no previous prototype for '__sanitizer_cov_trace_switch' [-Werror=missing-prototypes]Adding prototypes for these in a header solves that problem, but now there
is a mismatch between the built-in type and the prototype on 64-bit
architectures because they expect some functions to take a 64-bit
'unsigned long' argument rather than an 'unsigned long long' u64 type:include/linux/kcov.h:84:6: error: conflicting types for built-in function '__sanitizer_cov_trace_switch'; expected 'void(long long unsigned int, void *)' [-Werror=builtin-declaration-mismatch]
84 | void __sanitizer_cov_trace_switch(u64 val, u64 *cases);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~Avoid this as well with a custom type definition.
Link: https://lkml.kernel.org/r/20230517124944.929997-1-arnd@kernel.org
Signed-off-by: Arnd Bergmann
Cc: Andrey Konovalov
Cc: Dmitry Vyukov
Cc: Rong Tao
Signed-off-by: Andrew Morton -
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.Link: https://lkml.kernel.org/r/20230517131102.934196-15-arnd@kernel.org
Signed-off-by: Arnd Bergmann
Cc: Boqun Feng
Cc: Catalin Marinas
Cc: Christoph Lameter
Cc: Dennis Zhou
Cc: Eric Paris
Cc: Heiko Carstens
Cc: Helge Deller
Cc: Ingo Molnar
Cc: Michael Ellerman
Cc: Michal Simek
Cc: Palmer Dabbelt
Cc: Paul Moore
Cc: Pavel Machek
Cc: Peter Zijlstra
Cc: Rafael J. Wysocki
Cc: Russell King
Cc: Tejun Heo
Cc: Thomas Bogendoerfer
Cc: Thomas Gleixner
Cc: Waiman Long
Cc: Will Deacon
Signed-off-by: Andrew Morton -
There are a few __weak functions in kernel/fork.c, which architectures
can override. If there is no prototype, the compiler warns about them:kernel/fork.c:164:13: error: no previous prototype for 'arch_release_task_struct' [-Werror=missing-prototypes]
kernel/fork.c:991:20: error: no previous prototype for 'arch_task_cache_init' [-Werror=missing-prototypes]
kernel/fork.c:1086:12: error: no previous prototype for 'arch_dup_task_struct' [-Werror=missing-prototypes]There are already prototypes in a number of architecture specific headers
that have addressed those warnings before, but it's much better to have
these in a single place so the warning no longer shows up anywhere.Link: https://lkml.kernel.org/r/20230517131102.934196-14-arnd@kernel.org
Signed-off-by: Arnd Bergmann
Cc: Boqun Feng
Cc: Catalin Marinas
Cc: Christoph Lameter
Cc: Dennis Zhou
Cc: Eric Paris
Cc: Heiko Carstens
Cc: Helge Deller
Cc: Ingo Molnar
Cc: Michael Ellerman
Cc: Michal Simek
Cc: Palmer Dabbelt
Cc: Paul Moore
Cc: Pavel Machek
Cc: Peter Zijlstra
Cc: Rafael J. Wysocki
Cc: Russell King
Cc: Tejun Heo
Cc: Thomas Bogendoerfer
Cc: Thomas Gleixner
Cc: Waiman Long
Cc: Will Deacon
Signed-off-by: Andrew Morton -
cifs_root_data() is defined in cifs and called from early init code, but
lacks a global prototype:fs/cifs/cifsroot.c:83:12: error: no previous prototype for 'cifs_root_data'
Move the declaration from do_mounts.c into an appropriate header.
Link: https://lkml.kernel.org/r/20230517131102.934196-13-arnd@kernel.org
Signed-off-by: Arnd Bergmann
Cc: Boqun Feng
Cc: Catalin Marinas
Cc: Christoph Lameter
Cc: Dennis Zhou
Cc: Eric Paris
Cc: Heiko Carstens
Cc: Helge Deller
Cc: Ingo Molnar
Cc: Michael Ellerman
Cc: Michal Simek
Cc: Palmer Dabbelt
Cc: Paul Moore
Cc: Pavel Machek
Cc: Peter Zijlstra
Cc: Rafael J. Wysocki
Cc: Russell King
Cc: Tejun Heo
Cc: Thomas Bogendoerfer
Cc: Thomas Gleixner
Cc: Waiman Long
Cc: Will Deacon
Signed-off-by: Andrew Morton -
The init/main.c file contains some extern declarations for functions
defined in architecture code, and it defines some other functions that are
called from architecture code with a custom prototype. Both of those
result in warnings with 'make W=1':init/calibrate.c:261:37: error: no previous prototype for 'calibrate_delay_is_known' [-Werror=missing-prototypes]
init/main.c:790:20: error: no previous prototype for 'mem_encrypt_init' [-Werror=missing-prototypes]
init/main.c:792:20: error: no previous prototype for 'poking_init' [-Werror=missing-prototypes]
arch/arm64/kernel/irq.c:122:13: error: no previous prototype for 'init_IRQ' [-Werror=missing-prototypes]
arch/arm64/kernel/time.c:55:13: error: no previous prototype for 'time_init' [-Werror=missing-prototypes]
arch/x86/kernel/process.c:935:13: error: no previous prototype for 'arch_post_acpi_subsys_init' [-Werror=missing-prototypes]
init/calibrate.c:261:37: error: no previous prototype for 'calibrate_delay_is_known' [-Werror=missing-prototypes]
kernel/fork.c:991:20: error: no previous prototype for 'arch_task_cache_init' [-Werror=missing-prototypes]Add prototypes for all of these in include/linux/init.h or another
appropriate header, and remove the duplicate declarations from
architecture specific code.[sfr@canb.auug.org.au: declare time_init_early()]
Link: https://lkml.kernel.org/r/20230519124311.5167221c@canb.auug.org.au
Link: https://lkml.kernel.org/r/20230517131102.934196-12-arnd@kernel.org
Signed-off-by: Arnd Bergmann
Signed-off-by: Stephen Rothwell
Cc: Boqun Feng
Cc: Catalin Marinas
Cc: Christoph Lameter
Cc: Dennis Zhou
Cc: Eric Paris
Cc: Heiko Carstens
Cc: Helge Deller
Cc: Ingo Molnar
Cc: Michael Ellerman
Cc: Michal Simek
Cc: Palmer Dabbelt
Cc: Paul Moore
Cc: Pavel Machek
Cc: Peter Zijlstra
Cc: Rafael J. Wysocki
Cc: Russell King
Cc: Tejun Heo
Cc: Thomas Bogendoerfer
Cc: Thomas Gleixner
Cc: Waiman Long
Cc: Will Deacon
Signed-off-by: Andrew Morton -
An extra #include statement is needed to ensure the prototypes for debugfs
interfaces are visible, avoiding this warning:lib/kunit/debugfs.c:28:6: error: no previous prototype for 'kunit_debugfs_cleanup' [-Werror=missing-prototypes]
lib/kunit/debugfs.c:33:6: error: no previous prototype for 'kunit_debugfs_init' [-Werror=missing-prototypes]
lib/kunit/debugfs.c:102:6: error: no previous prototype for 'kunit_debugfs_create_suite' [-Werror=missing-prototypes]
lib/kunit/debugfs.c:118:6: error: no previous prototype for 'kunit_debugfs_destroy_suite' [-Werror=missing-prototypes]Link: https://lkml.kernel.org/r/20230517131102.934196-10-arnd@kernel.org
Signed-off-by: Arnd Bergmann
Reviewed-by: David Gow
Cc: Boqun Feng
Cc: Catalin Marinas
Cc: Christoph Lameter
Cc: Dennis Zhou
Cc: Eric Paris
Cc: Heiko Carstens
Cc: Helge Deller
Cc: Ingo Molnar
Cc: Michael Ellerman
Cc: Michal Simek
Cc: Palmer Dabbelt
Cc: Paul Moore
Cc: Pavel Machek
Cc: Peter Zijlstra
Cc: Rafael J. Wysocki
Cc: Russell King
Cc: Tejun Heo
Cc: Thomas Bogendoerfer
Cc: Thomas Gleixner
Cc: Waiman Long
Cc: Will Deacon
Signed-off-by: Andrew Morton -
A few panic() related functions have a global definition but not
declaration, which causes a warning with W=1:kernel/panic.c:710:6: error: no previous prototype for '__warn_printk' [-Werror=missing-prototypes]
kernel/panic.c:756:24: error: no previous prototype for '__stack_chk_fail' [-Werror=missing-prototypes]
kernel/exit.c:1917:32: error: no previous prototype for 'abort' [-Werror=missing-prototypes]__warn_printk() is called both as a global function when CONFIG_BUG
is enabled, and as a local function in other configs. The other
two here are called indirectly from generated or assembler code.Add prototypes for all of these.
Link: https://lkml.kernel.org/r/20230517131102.934196-9-arnd@kernel.org
Signed-off-by: Arnd Bergmann
Cc: Boqun Feng
Cc: Catalin Marinas
Cc: Christoph Lameter
Cc: Dennis Zhou
Cc: Eric Paris
Cc: Heiko Carstens
Cc: Helge Deller
Cc: Ingo Molnar
Cc: Michael Ellerman
Cc: Michal Simek
Cc: Palmer Dabbelt
Cc: Paul Moore
Cc: Pavel Machek
Cc: Peter Zijlstra
Cc: Rafael J. Wysocki
Cc: Russell King
Cc: Tejun Heo
Cc: Thomas Bogendoerfer
Cc: Thomas Gleixner
Cc: Waiman Long
Cc: Will Deacon
Signed-off-by: Andrew Morton -
Building with W=1 shows warnings about two functions that have no
declaration or caller in certain configurations:kernel/panic.c:688:6: error: no previous prototype for 'warn_slowpath_fmt' [-Werror=missing-prototypes]
kernel/panic.c:710:6: error: no previous prototype for '__warn_printk' [-Werror=missing-prototypes]Enclose the definition in the same #ifdef check as the declaration.
Link: https://lkml.kernel.org/r/20230517131102.934196-8-arnd@kernel.org
Signed-off-by: Arnd Bergmann
Cc: Boqun Feng
Cc: Catalin Marinas
Cc: Christoph Lameter
Cc: Dennis Zhou
Cc: Eric Paris
Cc: Heiko Carstens
Cc: Helge Deller
Cc: Ingo Molnar
Cc: Michael Ellerman
Cc: Michal Simek
Cc: Palmer Dabbelt
Cc: Paul Moore
Cc: Pavel Machek
Cc: Peter Zijlstra
Cc: Rafael J. Wysocki
Cc: Russell King
Cc: Tejun Heo
Cc: Thomas Bogendoerfer
Cc: Thomas Gleixner
Cc: Waiman Long
Cc: Will Deacon
Signed-off-by: Andrew Morton -
lockevent_read() has a __weak definition and the only caller in
kernel/locking/lock_events.c, plus a strong definition in qspinlock_stat.h
that overrides it, but no other declaration. This causes a W=1 warning:kernel/locking/lock_events.c:61:16: error: no previous prototype for 'lockevent_read' [-Werror=missing-prototypes]
Add shared prototype to avoid the warnings.
Link: https://lkml.kernel.org/r/20230517131102.934196-7-arnd@kernel.org
Signed-off-by: Arnd Bergmann
Cc: Boqun Feng
Cc: Catalin Marinas
Cc: Christoph Lameter
Cc: Dennis Zhou
Cc: Eric Paris
Cc: Heiko Carstens
Cc: Helge Deller
Cc: Ingo Molnar
Cc: Michael Ellerman
Cc: Michal Simek
Cc: Palmer Dabbelt
Cc: Paul Moore
Cc: Pavel Machek
Cc: Peter Zijlstra
Cc: Rafael J. Wysocki
Cc: Russell King
Cc: Tejun Heo
Cc: Thomas Bogendoerfer
Cc: Thomas Gleixner
Cc: Waiman Long
Cc: Will Deacon
Signed-off-by: Andrew Morton -
The devmem_is_allowed() function is defined in a file of the same name,
but the declaration is in asm/io.h, which is not included there, causing a
W=1 warning:lib/devmem_is_allowed.c:20:5: error: no previous prototype for 'devmem_is_allowed' [-Werror=missing-prototypes]
Include the appropriate header to avoid the warning.
Link: https://lkml.kernel.org/r/20230517131102.934196-6-arnd@kernel.org
Signed-off-by: Arnd Bergmann
Cc: Boqun Feng
Cc: Catalin Marinas
Cc: Christoph Lameter
Cc: Dennis Zhou
Cc: Eric Paris
Cc: Heiko Carstens
Cc: Helge Deller
Cc: Ingo Molnar
Cc: Michael Ellerman
Cc: Michal Simek
Cc: Palmer Dabbelt
Cc: Paul Moore
Cc: Pavel Machek
Cc: Peter Zijlstra
Cc: Rafael J. Wysocki
Cc: Russell King
Cc: Tejun Heo
Cc: Thomas Bogendoerfer
Cc: Thomas Gleixner
Cc: Waiman Long
Cc: Will Deacon
Signed-off-by: Andrew Morton -
There are two definitions of this function, but the second one lacks the
'static' annotation:mm/sparse.c:704:25: error: no previous prototype for 'populate_section_memmap' [-Werror=missing-prototypes]
Link: https://lkml.kernel.org/r/20230517131102.934196-4-arnd@kernel.org
Signed-off-by: Arnd Bergmann
Cc: Boqun Feng
Cc: Catalin Marinas
Cc: Christoph Lameter
Cc: Dennis Zhou
Cc: Eric Paris
Cc: Heiko Carstens
Cc: Helge Deller
Cc: Ingo Molnar
Cc: Michael Ellerman
Cc: Michal Simek
Cc: Palmer Dabbelt
Cc: Paul Moore
Cc: Pavel Machek
Cc: Peter Zijlstra
Cc: Rafael J. Wysocki
Cc: Russell King
Cc: Tejun Heo
Cc: Thomas Bogendoerfer
Cc: Thomas Gleixner
Cc: Waiman Long
Cc: Will Deacon
Signed-off-by: Andrew Morton -
The __kernel_map_pages() function is mainly used for
CONFIG_DEBUG_PAGEALLOC, but has a number of architecture specific
definitions that may also be used in other configurations, as well as a
global fallback definition for architectures that do not support
DEBUG_PAGEALLOC.When the option is disabled, any definitions without the prototype cause a
warning:mm/page_poison.c:102:6: error: no previous prototype for '__kernel_map_pages' [-Werror=missing-prototypes]
The function is a trivial nop here, so just declare it anyway
to avoid the warning.Link: https://lkml.kernel.org/r/20230517131102.934196-3-arnd@kernel.org
Signed-off-by: Arnd Bergmann
Cc: Boqun Feng
Cc: Catalin Marinas
Cc: Christoph Lameter
Cc: Dennis Zhou
Cc: Eric Paris
Cc: Heiko Carstens
Cc: Helge Deller
Cc: Ingo Molnar
Cc: Michael Ellerman
Cc: Michal Simek
Cc: Palmer Dabbelt
Cc: Paul Moore
Cc: Pavel Machek
Cc: Peter Zijlstra
Cc: Rafael J. Wysocki
Cc: Russell King
Cc: Tejun Heo
Cc: Thomas Bogendoerfer
Cc: Thomas Gleixner
Cc: Waiman Long
Cc: Will Deacon
Signed-off-by: Andrew Morton -
Patch series "mm/init/kernel: missing-prototypes warnings".
These are patches addressing -Wmissing-prototypes warnings in common
kernel code and memory management code files that usually get merged
through the -mm tree.This patch (of 12):
This function is called whenever CONFIG_NEED_PER_CPU_EMBED_FIRST_CHUNK or
CONFIG_HAVE_SETUP_PER_CPU_AREA, but only declared when the former is set:mm/percpu.c:3055:12: error: no previous prototype for 'pcpu_embed_first_chunk' [-Werror=missing-prototypes]
There is no real point in hiding declarations, so just remove
the #ifdef here.Link: https://lkml.kernel.org/r/20230517131102.934196-1-arnd@kernel.org
Link: https://lkml.kernel.org/r/20230517131102.934196-2-arnd@kernel.org
Signed-off-by: Arnd Bergmann
Cc: Boqun Feng
Cc: Catalin Marinas
Cc: Christoph Lameter
Cc: Dennis Zhou
Cc: Eric Paris
Cc: Heiko Carstens
Cc: Helge Deller
Cc: Ingo Molnar
Cc: Michael Ellerman
Cc: Michal Simek
Cc: Palmer Dabbelt
Cc: Paul Moore
Cc: Pavel Machek
Cc: Peter Zijlstra
Cc: Rafael J. Wysocki
Cc: Russell King
Cc: Tejun Heo
Cc: Thomas Bogendoerfer
Cc: Thomas Gleixner
Cc: Waiman Long
Cc: Will Deacon
Signed-off-by: Andrew Morton -
Before commit 93e72b3c612adcaca1 ("squashfs: migrate from ll_rw_block
usage to BIO"), compressed blocks read by squashfs were cached in the page
cache, but that is not the case after that commit. That has lead to
squashfs having to re-read a lot of sectors from disk/flash.For example, the first sectors of every metadata block need to be read
twice from the disk. Once partially to read the length, and a second time
to read the block itself. Also, in linear reads of large files, the last
sectors of one data block are re-read from disk when reading the next data
block, since the compressed blocks are of variable sizes and not aligned
to device blocks. This extra I/O results in a degrade in read performance
of, for example, ~16% in one scenario on my ARM platform using squashfs
with dm-verity and NAND.Since the decompressed data is cached in the page cache or squashfs'
internal metadata and fragment caches, caching _all_ compressed pages
would lead to a lot of double caching and is undesirable. But make the
code cache any disk blocks which were only partially requested, since
these are the ones likely to include data which is needed by other file
system blocks. This restores read performance in my test scenario.The compressed block caching is only applied when the disk block size is
equal to the page size, to avoid having to deal with caching sub-page
reads.[akpm@linux-foundation.org: fs/squashfs/block.c needs linux/pagemap.h]
[vincent.whitchurch@axis.com: fix page update race]
Link: https://lkml.kernel.org/r/20230526-squashfs-cache-fixup-v1-1-d54a7fa23e7b@axis.com
[vincent.whitchurch@axis.com: fix page indices]
Link: https://lkml.kernel.org/r/20230526-squashfs-cache-fixup-v1-2-d54a7fa23e7b@axis.com
[akpm@linux-foundation.org: fix layout, per hch]
Link: https://lkml.kernel.org/r/20230510-squashfs-cache-v4-1-3bd394e1ee71@axis.com
Signed-off-by: Vincent Whitchurch
Reviewed-by: Christoph Hellwig
Reviewed-by: Phillip Lougher
Signed-off-by: Andrew Morton -
Squashfs has stopped using buffers heads in 93e72b3c612adcaca1
("squashfs: migrate from ll_rw_block usage to BIO").Link: https://lkml.kernel.org/r/20230517071622.245151-1-hch@lst.de
Signed-off-by: Christoph Hellwig
Reviewed-by: Pankaj Raghav
Reviewed-by: Phillip Lougher
Signed-off-by: Andrew Morton -
Since commit f1c1a9ee00e4 ("fork: Move memcg_charge_kernel_stack()
into CONFIG_VMAP_STACK"), memcg_charge_kernel_stack() has been moved
into CONFIG_VMAP_STACK block, so the CONFIG_VMAP_STACK check can be
removed.Furthermore, memcg_charge_kernel_stack() is only invoked by
alloc_thread_stack_node() instead of dup_task_struct(). If
memcg_kmem_charge_page() fails, the uncharge process is handled in
memcg_charge_kernel_stack() itself instead of free_thread_stack(),
so remove the incorrect comments.If memcg_charge_kernel_stack() fails to charge pages used by kernel
stack, only charged pages need to be uncharged. It's unnecessary to
uncharge those pages which memory cgroup pointer is NULL.[akpm@linux-foundation.org: remove assertion that PAGE_SIZE is a multiple of 1k]
Link: https://lkml.kernel.org/r/20230508064458.32855-1-haifeng.xu@shopee.com
Signed-off-by: Haifeng Xu
Cc: Andy Lutomirski
Cc: Daniel Bristot de Oliveira
Cc: Sebastian Andrzej Siewior
Cc: Thomas Gleixner
Signed-off-by: Andrew Morton -
Add signed intptr_t given that a) it is standard type and b) uintptr_t is
in tree.Link: https://lkml.kernel.org/r/ed66b9e4-1fb7-45be-9bb9-d4bc291c691f@p183
Signed-off-by: Alexey Dobriyan
Signed-off-by: Andrew Morton
