Add a new pointer argument to cpuidle_select() and to the ->select
cpuidle governor callback to allow a boolean value indicating
whether or not the tick should be stopped before entering the
selected state to be returned from there.
Make the ladder governor ignore that pointer (to preserve its
current behavior) and make the menu governor return 'false" through
it if:
(1) the idle exit latency is constrained at 0, or
(2) the selected state is a polling one, or
(3) the expected idle period duration is within the tick period
range.
In addition to that, the correction factor computations in the menu
governor need to take the possibility that the tick may not be
stopped into account to avoid artificially small correction factor
values. To that end, add a mechanism to record tick wakeups, as
suggested by Peter Zijlstra, and use it to modify the menu_update()
behavior when tick wakeup occurs. Namely, if the CPU is woken up by
the tick and the return value of tick_nohz_get_sleep_length() is not
within the tick boundary, the predicted idle duration is likely too
short, so make menu_update() try to compensate for that by updating
the governor statistics as though the CPU was idle for a long time.
Since the value returned through the new argument pointer of
cpuidle_select() is not used by its caller yet, this change by
itself is not expected to alter the functionality of the code.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Since the subsequent changes will need a TICK_USEC definition
analogous to TICK_NSEC, rename the existing TICK_USEC as
USER_TICK_USEC, update its users and redefine TICK_USEC
accordingly.
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Make cpuidle_idle_call() decide whether or not to stop the tick.
First, the cpuidle_enter_s2idle() path deals with the tick (and with
the entire timekeeping for that matter) by itself and it doesn't need
the tick to be stopped beforehand.
Second, to address the issue with short idle duration predictions
by the idle governor after the tick has been stopped, it will be
necessary to change the ordering of cpuidle_select() with respect
to tick_nohz_idle_stop_tick(). To prepare for that, put a
tick_nohz_idle_stop_tick() call in the same branch in which
cpuidle_select() is called.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Push the decision whether or not to stop the tick somewhat deeper
into the idle loop.
Stopping the tick upfront leads to unpleasant outcomes in case the
idle governor doesn't agree with the nohz code on the duration of the
upcoming idle period. Specifically, if the tick has been stopped and
the idle governor predicts short idle, the situation is bad regardless
of whether or not the prediction is accurate. If it is accurate, the
tick has been stopped unnecessarily which means excessive overhead.
If it is not accurate, the CPU is likely to spend too much time in
the (shallow, because short idle has been predicted) idle state
selected by the governor [1].
As the first step towards addressing this problem, change the code
to make the tick stopping decision inside of the loop in do_idle().
In particular, do not stop the tick in the cpu_idle_poll() code path.
Also don't do that in tick_nohz_irq_exit() which doesn't really have
enough information on whether or not to stop the tick.
Link: https://marc.info/?l=linux-pm&m=150116085925208&w=2 # [1]
Link: https://tu-dresden.de/zih/forschung/ressourcen/dateien/projekte/haec/powernightmares.pdf
Suggested-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Prepare the scheduler tick code for reworking the idle loop to
avoid stopping the tick in some cases.
The idea is to split the nohz idle entry call to decouple the idle
time stats accounting and preparatory work from the actual tick stop
code, in order to later be able to delay the tick stop once we reach
more power-knowledgeable callers.
Move away the tick_nohz_start_idle() invocation from
__tick_nohz_idle_enter(), rename the latter to
__tick_nohz_idle_stop_tick() and define tick_nohz_idle_stop_tick()
as a wrapper around it for calling it from the outside.
Make tick_nohz_idle_enter() only call tick_nohz_start_idle() instead
of calling the entire __tick_nohz_idle_enter(), add another wrapper
disabling and enabling interrupts around tick_nohz_idle_stop_tick()
and make the current callers of tick_nohz_idle_enter() call it too
to retain their current functionality.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
- Modify the cpuidle poll state implementation to prevent CPUs from
staying in the loop in there for excessive times (Rafael Wysocki).
- Add Intel Cannon Lake chips support to the RAPL power capping
driver (Joe Konno).
- Add reference counting to the device links handling code in the
PM core (Lukas Wunner).
- Avoid reconfiguring GPEs on suspend-to-idle in the ACPI system
suspend code (Rafael Wysocki).
- Allow devices to be put into deeper low-power states via ACPI
if both _SxD and _SxW are missing (Daniel Drake).
- Reorganize the core ACPI suspend-to-idle wakeup code to avoid a
keyboard wakeup issue on Asus UX331UA (Chris Chiu).
- Prevent the PCMCIA library code from aborting suspend-to-idle due
to noirq suspend failures resulting from incorrect assumptions
(Rafael Wysocki).
- Add coupled cpuidle supprt to the Exynos3250 platform (Marek
Szyprowski).
- Add new sysfs file to make it easier to specify the image storage
location during hibernation (Mario Limonciello).
- Add sysfs files for collecting suspend-to-idle usage and time
statistics for CPU idle states (Rafael Wysocki).
- Update the pm-graph utilities (Todd Brandt).
- Reduce the kernel log noise related to reporting Low-power Idle
constraings by the ACPI system suspend code (Rafael Wysocki).
- Make it easier to distinguish dedicated wakeup IRQs in the
/proc/interrupts output (Tony Lindgren).
- Add the frequency table validation in cpufreq to the core and
drop it from a number of cpufreq drivers (Viresh Kumar).
- Drop "cooling-{min|max}-level" for CPU nodes from a couple of
DT bindings (Viresh Kumar).
- Clean up the CPU online error code path in the cpufreq core
(Viresh Kumar).
- Fix assorted issues in the SCPI, CPPC, mediatek and tegra186
cpufreq drivers (Arnd Bergmann, Chunyu Hu, George Cherian,
Viresh Kumar).
- Drop memory allocation error messages from a few places in
cpufreq and cpuildle drivers (Markus Elfring).
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2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=6JC2
-----END PGP SIGNATURE-----
Merge tag 'pm-4.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management updates from Rafael Wysocki:
"These update the cpuidle poll state definition to reduce excessive
energy usage related to it, add new CPU ID to the RAPL power capping
driver, update the ACPI system suspend code to handle some special
cases better, extend the PM core's device links code slightly, add new
sysfs attribute for better suspend-to-idle diagnostics and easier
hibernation handling, update power management tools and clean up
cpufreq quite a bit.
Specifics:
- Modify the cpuidle poll state implementation to prevent CPUs from
staying in the loop in there for excessive times (Rafael Wysocki).
- Add Intel Cannon Lake chips support to the RAPL power capping
driver (Joe Konno).
- Add reference counting to the device links handling code in the PM
core (Lukas Wunner).
- Avoid reconfiguring GPEs on suspend-to-idle in the ACPI system
suspend code (Rafael Wysocki).
- Allow devices to be put into deeper low-power states via ACPI if
both _SxD and _SxW are missing (Daniel Drake).
- Reorganize the core ACPI suspend-to-idle wakeup code to avoid a
keyboard wakeup issue on Asus UX331UA (Chris Chiu).
- Prevent the PCMCIA library code from aborting suspend-to-idle due
to noirq suspend failures resulting from incorrect assumptions
(Rafael Wysocki).
- Add coupled cpuidle supprt to the Exynos3250 platform (Marek
Szyprowski).
- Add new sysfs file to make it easier to specify the image storage
location during hibernation (Mario Limonciello).
- Add sysfs files for collecting suspend-to-idle usage and time
statistics for CPU idle states (Rafael Wysocki).
- Update the pm-graph utilities (Todd Brandt).
- Reduce the kernel log noise related to reporting Low-power Idle
constraings by the ACPI system suspend code (Rafael Wysocki).
- Make it easier to distinguish dedicated wakeup IRQs in the
/proc/interrupts output (Tony Lindgren).
- Add the frequency table validation in cpufreq to the core and drop
it from a number of cpufreq drivers (Viresh Kumar).
- Drop "cooling-{min|max}-level" for CPU nodes from a couple of DT
bindings (Viresh Kumar).
- Clean up the CPU online error code path in the cpufreq core (Viresh
Kumar).
- Fix assorted issues in the SCPI, CPPC, mediatek and tegra186
cpufreq drivers (Arnd Bergmann, Chunyu Hu, George Cherian, Viresh
Kumar).
- Drop memory allocation error messages from a few places in cpufreq
and cpuildle drivers (Markus Elfring)"
* tag 'pm-4.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (56 commits)
ACPI / PM: Fix keyboard wakeup from suspend-to-idle on ASUS UX331UA
cpufreq: CPPC: Use transition_delay_us depending transition_latency
PM / hibernate: Change message when writing to /sys/power/resume
PM / hibernate: Make passing hibernate offsets more friendly
cpuidle: poll_state: Avoid invoking local_clock() too often
PM: cpuidle/suspend: Add s2idle usage and time state attributes
cpuidle: Enable coupled cpuidle support on Exynos3250 platform
cpuidle: poll_state: Add time limit to poll_idle()
cpufreq: tegra186: Don't validate the frequency table twice
cpufreq: speedstep: Don't validate the frequency table twice
cpufreq: sparc: Don't validate the frequency table twice
cpufreq: sh: Don't validate the frequency table twice
cpufreq: sfi: Don't validate the frequency table twice
cpufreq: scpi: Don't validate the frequency table twice
cpufreq: sc520: Don't validate the frequency table twice
cpufreq: s3c24xx: Don't validate the frequency table twice
cpufreq: qoirq: Don't validate the frequency table twice
cpufreq: pxa: Don't validate the frequency table twice
cpufreq: ppc_cbe: Don't validate the frequency table twice
cpufreq: powernow: Don't validate the frequency table twice
...
Pull removal of in-kernel calls to syscalls from Dominik Brodowski:
"System calls are interaction points between userspace and the kernel.
Therefore, system call functions such as sys_xyzzy() or
compat_sys_xyzzy() should only be called from userspace via the
syscall table, but not from elsewhere in the kernel.
At least on 64-bit x86, it will likely be a hard requirement from
v4.17 onwards to not call system call functions in the kernel: It is
better to use use a different calling convention for system calls
there, where struct pt_regs is decoded on-the-fly in a syscall wrapper
which then hands processing over to the actual syscall function. This
means that only those parameters which are actually needed for a
specific syscall are passed on during syscall entry, instead of
filling in six CPU registers with random user space content all the
time (which may cause serious trouble down the call chain). Those
x86-specific patches will be pushed through the x86 tree in the near
future.
Moreover, rules on how data may be accessed may differ between kernel
data and user data. This is another reason why calling sys_xyzzy() is
generally a bad idea, and -- at most -- acceptable in arch-specific
code.
This patchset removes all in-kernel calls to syscall functions in the
kernel with the exception of arch/. On top of this, it cleans up the
three places where many syscalls are referenced or prototyped, namely
kernel/sys_ni.c, include/linux/syscalls.h and include/linux/compat.h"
* 'syscalls-next' of git://git.kernel.org/pub/scm/linux/kernel/git/brodo/linux: (109 commits)
bpf: whitelist all syscalls for error injection
kernel/sys_ni: remove {sys_,sys_compat} from cond_syscall definitions
kernel/sys_ni: sort cond_syscall() entries
syscalls/x86: auto-create compat_sys_*() prototypes
syscalls: sort syscall prototypes in include/linux/compat.h
net: remove compat_sys_*() prototypes from net/compat.h
syscalls: sort syscall prototypes in include/linux/syscalls.h
kexec: move sys_kexec_load() prototype to syscalls.h
x86/sigreturn: use SYSCALL_DEFINE0
x86: fix sys_sigreturn() return type to be long, not unsigned long
x86/ioport: add ksys_ioperm() helper; remove in-kernel calls to sys_ioperm()
mm: add ksys_readahead() helper; remove in-kernel calls to sys_readahead()
mm: add ksys_mmap_pgoff() helper; remove in-kernel calls to sys_mmap_pgoff()
mm: add ksys_fadvise64_64() helper; remove in-kernel call to sys_fadvise64_64()
fs: add ksys_fallocate() wrapper; remove in-kernel calls to sys_fallocate()
fs: add ksys_p{read,write}64() helpers; remove in-kernel calls to syscalls
fs: add ksys_truncate() wrapper; remove in-kernel calls to sys_truncate()
fs: add ksys_sync_file_range helper(); remove in-kernel calls to syscall
kernel: add ksys_setsid() helper; remove in-kernel call to sys_setsid()
kernel: add ksys_unshare() helper; remove in-kernel calls to sys_unshare()
...
This removes the entire architecture code for blackfin, cris, frv, m32r,
metag, mn10300, score, and tile, including the associated device drivers.
I have been working with the (former) maintainers for each one to ensure
that my interpretation was right and the code is definitely unused in
mainline kernels. Many had fond memories of working on the respective
ports to start with and getting them included in upstream, but also saw
no point in keeping the port alive without any users.
In the end, it seems that while the eight architectures are extremely
different, they all suffered the same fate: There was one company
in charge of an SoC line, a CPU microarchitecture and a software
ecosystem, which was more costly than licensing newer off-the-shelf
CPU cores from a third party (typically ARM, MIPS, or RISC-V). It seems
that all the SoC product lines are still around, but have not used the
custom CPU architectures for several years at this point. In contrast,
CPU instruction sets that remain popular and have actively maintained
kernel ports tend to all be used across multiple licensees.
The removal came out of a discussion that is now documented at
https://lwn.net/Articles/748074/. Unlike the original plans, I'm not
marking any ports as deprecated but remove them all at once after I made
sure that they are all unused. Some architectures (notably tile, mn10300,
and blackfin) are still being shipped in products with old kernels,
but those products will never be updated to newer kernel releases.
After this series, we still have a few architectures without mainline
gcc support:
- unicore32 and hexagon both have very outdated gcc releases, but the
maintainers promised to work on providing something newer. At least
in case of hexagon, this will only be llvm, not gcc.
- openrisc, risc-v and nds32 are still in the process of finishing their
support or getting it added to mainline gcc in the first place.
They all have patched gcc-7.3 ports that work to some degree, but
complete upstream support won't happen before gcc-8.1. Csky posted
their first kernel patch set last week, their situation will be similar.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1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=fQ8z
-----END PGP SIGNATURE-----
Merge tag 'arch-removal' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic
Pul removal of obsolete architecture ports from Arnd Bergmann:
"This removes the entire architecture code for blackfin, cris, frv,
m32r, metag, mn10300, score, and tile, including the associated device
drivers.
I have been working with the (former) maintainers for each one to
ensure that my interpretation was right and the code is definitely
unused in mainline kernels. Many had fond memories of working on the
respective ports to start with and getting them included in upstream,
but also saw no point in keeping the port alive without any users.
In the end, it seems that while the eight architectures are extremely
different, they all suffered the same fate: There was one company in
charge of an SoC line, a CPU microarchitecture and a software
ecosystem, which was more costly than licensing newer off-the-shelf
CPU cores from a third party (typically ARM, MIPS, or RISC-V). It
seems that all the SoC product lines are still around, but have not
used the custom CPU architectures for several years at this point. In
contrast, CPU instruction sets that remain popular and have actively
maintained kernel ports tend to all be used across multiple licensees.
[ See the new nds32 port merged in the previous commit for the next
generation of "one company in charge of an SoC line, a CPU
microarchitecture and a software ecosystem" - Linus ]
The removal came out of a discussion that is now documented at
https://lwn.net/Articles/748074/. Unlike the original plans, I'm not
marking any ports as deprecated but remove them all at once after I
made sure that they are all unused. Some architectures (notably tile,
mn10300, and blackfin) are still being shipped in products with old
kernels, but those products will never be updated to newer kernel
releases.
After this series, we still have a few architectures without mainline
gcc support:
- unicore32 and hexagon both have very outdated gcc releases, but the
maintainers promised to work on providing something newer. At least
in case of hexagon, this will only be llvm, not gcc.
- openrisc, risc-v and nds32 are still in the process of finishing
their support or getting it added to mainline gcc in the first
place. They all have patched gcc-7.3 ports that work to some
degree, but complete upstream support won't happen before gcc-8.1.
Csky posted their first kernel patch set last week, their situation
will be similar
[ Palmer Dabbelt points out that RISC-V support is in mainline gcc
since gcc-7, although gcc-7.3.0 is the recommended minimum - Linus ]"
This really says it all:
2498 files changed, 95 insertions(+), 467668 deletions(-)
* tag 'arch-removal' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic: (74 commits)
MAINTAINERS: UNICORE32: Change email account
staging: iio: remove iio-trig-bfin-timer driver
tty: hvc: remove tile driver
tty: remove bfin_jtag_comm and hvc_bfin_jtag drivers
serial: remove tile uart driver
serial: remove m32r_sio driver
serial: remove blackfin drivers
serial: remove cris/etrax uart drivers
usb: Remove Blackfin references in USB support
usb: isp1362: remove blackfin arch glue
usb: musb: remove blackfin port
usb: host: remove tilegx platform glue
pwm: remove pwm-bfin driver
i2c: remove bfin-twi driver
spi: remove blackfin related host drivers
watchdog: remove bfin_wdt driver
can: remove bfin_can driver
mmc: remove bfin_sdh driver
input: misc: remove blackfin rotary driver
input: keyboard: remove bf54x driver
...
Pull wait_var_event updates from Ingo Molnar:
"This introduces the new wait_var_event() API, which is a more flexible
waiting primitive than wait_on_atomic_t().
All wait_on_atomic_t() users are migrated over to the new API and
wait_on_atomic_t() is removed. The migration fixes one bug and should
result in no functional changes for the other usecases"
* 'sched-wait-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/wait: Improve __var_waitqueue() code generation
sched/wait: Remove the wait_on_atomic_t() API
sched/wait, arch/mips: Fix and convert wait_on_atomic_t() usage to the new wait_var_event() API
sched/wait, fs/ocfs2: Convert wait_on_atomic_t() usage to the new wait_var_event() API
sched/wait, fs/nfs: Convert wait_on_atomic_t() usage to the new wait_var_event() API
sched/wait, fs/fscache: Convert wait_on_atomic_t() usage to the new wait_var_event() API
sched/wait, fs/btrfs: Convert wait_on_atomic_t() usage to the new wait_var_event() API
sched/wait, fs/afs: Convert wait_on_atomic_t() usage to the new wait_var_event() API
sched/wait, drivers/media: Convert wait_on_atomic_t() usage to the new wait_var_event() API
sched/wait, drivers/drm: Convert wait_on_atomic_t() usage to the new wait_var_event() API
sched/wait: Introduce wait_var_event()
Pull SMP hotplug updates from Ingo Molnar:
"Simplify the CPU hot-plug state machine"
* 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
cpu/hotplug: Fix unused function warning
cpu/hotplug: Merge cpuhp_bp_states and cpuhp_ap_states
Pull scheduler updates from Ingo Molnar:
"The main scheduler changes in this cycle were:
- NUMA balancing improvements (Mel Gorman)
- Further load tracking improvements (Patrick Bellasi)
- Various NOHZ balancing cleanups and optimizations (Peter Zijlstra)
- Improve blocked load handling, in particular we can now reduce and
eventually stop periodic load updates on 'very idle' CPUs. (Vincent
Guittot)
- On isolated CPUs offload the final 1Hz scheduler tick as well, plus
related cleanups and reorganization. (Frederic Weisbecker)
- Core scheduler code cleanups (Ingo Molnar)"
* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (45 commits)
sched/core: Update preempt_notifier_key to modern API
sched/cpufreq: Rate limits for SCHED_DEADLINE
sched/fair: Update util_est only on util_avg updates
sched/cpufreq/schedutil: Use util_est for OPP selection
sched/fair: Use util_est in LB and WU paths
sched/fair: Add util_est on top of PELT
sched/core: Remove TASK_ALL
sched/completions: Use bool in try_wait_for_completion()
sched/fair: Update blocked load when newly idle
sched/fair: Move idle_balance()
sched/nohz: Merge CONFIG_NO_HZ_COMMON blocks
sched/fair: Move rebalance_domains()
sched/nohz: Optimize nohz_idle_balance()
sched/fair: Reduce the periodic update duration
sched/nohz: Stop NOHZ stats when decayed
sched/cpufreq: Provide migration hint
sched/nohz: Clean up nohz enter/exit
sched/fair: Update blocked load from NEWIDLE
sched/fair: Add NOHZ stats balancing
sched/fair: Restructure nohz_balance_kick()
...
This keeps it in line with the SYSCALL_DEFINEx() / COMPAT_SYSCALL_DEFINEx()
calling convention.
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Shuffle the cond_syscall() entries in kernel/sys_ni.c around so that they
are kept in the same order as in include/uapi/asm-generic/unistd.h. For
better structuring, add the same comments as in that file, but keep a few
additional comments and extend the commentary where it seems useful.
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Using this helper allows us to avoid the in-kernel call to the
sys_setsid() syscall. The ksys_ prefix denotes that this function
is meant as a drop-in replacement for the syscall. In particular, it
uses the same calling convention as sys_setsid().
This patch is part of a series which removes in-kernel calls to syscalls.
On this basis, the syscall entry path can be streamlined. For details, see
http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.net
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Using this helper allows us to avoid the in-kernel calls to the
sys_unshare() syscall. The ksys_ prefix denotes that this function is meant
as a drop-in replacement for the syscall. In particular, it uses the same
calling convention as sys_unshare().
This patch is part of a series which removes in-kernel calls to syscalls.
On this basis, the syscall entry path can be streamlined. For details, see
http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.net
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Using this helper allows us to avoid the in-kernel calls to the
sys_sync() syscall. The ksys_ prefix denotes that this function
is meant as a drop-in replacement for the syscall. In particular, it
uses the same calling convention as sys_sync().
This patch is part of a series which removes in-kernel calls to syscalls.
On this basis, the syscall entry path can be streamlined. For details, see
http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.net
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Using the fs-interal do_fchownat() wrapper allows us to get rid of
fs-internal calls to the sys_fchownat() syscall.
Introducing the ksys_fchown() helper and the ksys_{,}chown() wrappers
allows us to avoid the in-kernel calls to the sys_{,l,f}chown() syscalls.
The ksys_ prefix denotes that these functions are meant as a drop-in
replacement for the syscalls. In particular, they use the same calling
convention as sys_{,l,f}chown().
This patch is part of a series which removes in-kernel calls to syscalls.
On this basis, the syscall entry path can be streamlined. For details, see
http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.net
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
While sys32_quotactl() is only needed on x86, it can use the recommended
COMPAT_SYSCALL_DEFINEx() machinery for its setup.
Acked-by: Jan Kara <jack@suse.cz>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Move compat_sys_move_pages() to mm/migrate.c and make it call a newly
introduced helper -- kernel_move_pages() -- instead of the syscall.
This patch is part of a series which removes in-kernel calls to syscalls.
On this basis, the syscall entry path can be streamlined. For details, see
http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.net
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-mm@kvack.org
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Move compat_sys_migrate_pages() to mm/mempolicy.c and make it call a newly
introduced helper -- kernel_migrate_pages() -- instead of the syscall.
This patch is part of a series which removes in-kernel calls to syscalls.
On this basis, the syscall entry path can be streamlined. For details, see
http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.net
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-mm@kvack.org
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Using the sched-internal do_sched_yield() helper allows us to get rid of
the sched-internal call to the sys_sched_yield() syscall.
This patch is part of a series which removes in-kernel calls to syscalls.
On this basis, the syscall entry path can be streamlined. For details, see
http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.net
Cc: Ingo Molnar <mingo@redhat.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Using these helpers allows us to avoid the in-kernel calls to these
syscalls: sys_setregid(), sys_setgid(), sys_setreuid(), sys_setuid(),
sys_setresuid(), sys_setresgid(), sys_setfsuid(), and sys_setfsgid().
The ksys_ prefix denotes that these function are meant as a drop-in
replacement for the syscall. In particular, they use the same calling
convention.
This patch is part of a series which removes in-kernel calls to syscalls.
On this basis, the syscall entry path can be streamlined. For details, see
http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.net
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Using this helper allows us to avoid the in-kernel call to the
compat_sys_sigaltstack() syscall.
This patch is part of a series which removes in-kernel calls to syscalls.
On this basis, the syscall entry path can be streamlined. For details, see
http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.net
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Using the do_getpgid() helper removes an in-kernel call to the
sys_getpgid() syscall.
This patch is part of a series which removes in-kernel calls to syscalls.
On this basis, the syscall entry path can be streamlined. For details, see
http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.net
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
sys_futex() is a wrapper to do_futex() which does not modify any
values here:
- uaddr, val and val3 are kept the same
- op is masked with FUTEX_CMD_MASK, but is always set to FUTEX_WAKE.
Therefore, val2 is always 0.
- as utime is set to NULL, *timeout is NULL
This patch is part of a series which removes in-kernel calls to syscalls.
On this basis, the syscall entry path can be streamlined. For details, see
http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.net
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Darren Hart <dvhart@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
do_kexec_load() can be called directly by compat_sys_kexec() as long as
the same parameters checks are completed which are currently handled
(also) by sys_kexec(). Therefore, move those to kexec_load_check(),
call that newly introduced helper function from both sys_kexec() and
compat_sys_kexec(), and duplicate the remaining code from sys_kexec()
in compat_sys_kexec().
This patch is part of a series which removes in-kernel calls to syscalls.
On this basis, the syscall entry path can be streamlined. For details, see
http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.net
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: kexec@lists.infradead.org
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
A similar but not fully equivalent code path is already open-coded
three times (in sys_rt_sigpending and in the two compat stubs), so
do it a fourth time here.
This patch is part of a series which removes in-kernel calls to syscalls.
On this basis, the syscall entry path can be streamlined. For details, see
http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.net
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
All call sites of sys_wait4() set *rusage to NULL. Therefore, there is
no need for the copy_to_user() handling of *rusage, and we can use
kernel_wait4() directly.
This patch is part of a series which removes in-kernel calls to syscalls.
On this basis, the syscall entry path can be streamlined. For details, see
http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.net
Acked-by: Luis R. Rodriguez <mcgrof@kernel.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Pull perf updates from Ingo Molnar:
"The main kernel side changes were:
- Modernize the kprobe and uprobe creation/destruction tooling ABIs:
The existing text based APIs (kprobe_events and uprobe_events in
tracefs), are naive, limited ABIs in that they require user-space
to clean up after themselves, which is both difficult and fragile
if the tool is buggy or exits unexpectedly. In other words they are
not really suited for modern, robust tooling.
So introduce a modern, file descriptor based ABI that does not have
these limitations: introduce the 'perf_kprobe' and 'perf_uprobe'
PMUs and extend the perf_event_open() syscall to create events with
a kprobe/uprobe attached to them. These [k,u]probe are associated
with this file descriptor, so they are not available in tracefs.
(Song Liu)
- Intel Cannon Lake CPU support (Harry Pan)
- Intel PT cleanups (Alexander Shishkin)
- Improve the performance of pinned/flexible event groups by using RB
trees (Alexey Budankov)
- Add PERF_EVENT_IOC_MODIFY_ATTRIBUTES which allows the modification
of hardware breakpoints, which new ABI variant massively speeds up
existing tooling that uses hardware breakpoints to instrument (and
debug) memory usage.
(Milind Chabbi, Jiri Olsa)
- Various Intel PEBS handling fixes and improvements, and other Intel
PMU improvements (Kan Liang)
- Various perf core improvements and optimizations (Peter Zijlstra)
- ... misc cleanups, fixes and updates.
There's over 200 tooling commits, here's an (imperfect) list of
highlights:
- 'perf annotate' improvements:
* Recognize and handle jumps to other functions as calls, which
improves the navigation along jumps and back. (Arnaldo Carvalho
de Melo)
* Add the 'P' hotkey in TUI annotation to dump annotation output
into a file, to ease e-mail reporting of annotation details.
(Arnaldo Carvalho de Melo)
* Add an IPC/cycles column to the TUI (Jin Yao)
* Improve s390 assembly annotation (Thomas Richter)
* Refactor the output formatting logic to better separate it into
interactive and non-interactive features and add the --stdio2
output variant to demonstrate this. (Arnaldo Carvalho de Melo)
- 'perf script' improvements:
* Add Python 3 support (Jaroslav Škarvada)
* Add --show-round-event (Jiri Olsa)
- 'perf c2c' improvements:
* Add NUMA analysis support (Jiri Olsa)
- 'perf trace' improvements:
* Improve PowerPC support (Ravi Bangoria)
- 'perf inject' improvements:
* Integrate ARM CoreSight traces (Robert Walker)
- 'perf stat' improvements:
* Add the --interval-count option (yuzhoujian)
* Add the --timeout option (yuzhoujian)
- 'perf sched' improvements (Changbin Du)
- Vendor events improvements :
* Add IBM s390 vendor events (Thomas Richter)
* Add and improve arm64 vendor events (John Garry, Ganapatrao
Kulkarni)
* Update POWER9 vendor events (Sukadev Bhattiprolu)
- Intel PT tooling improvements (Adrian Hunter)
- PMU handling improvements (Agustin Vega-Frias)
- Record machine topology in perf.data (Jiri Olsa)
- Various overwrite related cleanups (Kan Liang)
- Add arm64 dwarf post unwind support (Kim Phillips, Jean Pihet)
- ... and lots of other changes, cleanups and fixes, see the shortlog
and Git history for details"
* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (262 commits)
perf/x86/intel: Enable C-state residency events for Cannon Lake
perf/x86/intel: Add Cannon Lake support for RAPL profiling
perf/x86/pt, coresight: Clean up address filter structure
perf vendor events s390: Add JSON files for IBM z14
perf vendor events s390: Add JSON files for IBM z13
perf vendor events s390: Add JSON files for IBM zEC12 zBC12
perf vendor events s390: Add JSON files for IBM z196
perf vendor events s390: Add JSON files for IBM z10EC z10BC
perf mmap: Be consistent when checking for an unmaped ring buffer
perf mmap: Fix accessing unmapped mmap in perf_mmap__read_done()
perf build: Fix check-headers.sh opts assignment
perf/x86: Update rdpmc_always_available static key to the modern API
perf annotate: Use absolute addresses to calculate jump target offsets
perf annotate: Defer searching for comma in raw line till it is needed
perf annotate: Support jumping from one function to another
perf annotate: Add "_local" to jump/offset validation routines
perf python: Reference Py_None before returning it
perf annotate: Mark jumps to outher functions with the call arrow
perf annotate: Pass function descriptor to its instruction parsing routines
perf annotate: No need to calculate notes->start twice
...
Pull locking updates from Ingo Molnar:
"The main changes in the locking subsystem in this cycle were:
- Add the Linux Kernel Memory Consistency Model (LKMM) subsystem,
which is an an array of tools in tools/memory-model/ that formally
describe the Linux memory coherency model (a.k.a.
Documentation/memory-barriers.txt), and also produce 'litmus tests'
in form of kernel code which can be directly executed and tested.
Here's a high level background article about an earlier version of
this work on LWN.net:
https://lwn.net/Articles/718628/
The design principles:
"There is reason to believe that Documentation/memory-barriers.txt
could use some help, and a major purpose of this patch is to
provide that help in the form of a design-time tool that can
produce all valid executions of a small fragment of concurrent
Linux-kernel code, which is called a "litmus test". This tool's
functionality is roughly similar to a full state-space search.
Please note that this is a design-time tool, not useful for
regression testing. However, we hope that the underlying
Linux-kernel memory model will be incorporated into other tools
capable of analyzing large bodies of code for regression-testing
purposes."
[...]
"A second tool is klitmus7, which converts litmus tests to
loadable kernel modules for direct testing. As with herd7, the
klitmus7 code is freely available from
http://diy.inria.fr/sources/index.html
(and via "git" at https://github.com/herd/herdtools7)"
[...]
Credits go to:
"This patch was the result of a most excellent collaboration
founded by Jade Alglave and also including Alan Stern, Andrea
Parri, and Luc Maranget."
... and to the gents listed in the MAINTAINERS entry:
LINUX KERNEL MEMORY CONSISTENCY MODEL (LKMM)
M: Alan Stern <stern@rowland.harvard.edu>
M: Andrea Parri <parri.andrea@gmail.com>
M: Will Deacon <will.deacon@arm.com>
M: Peter Zijlstra <peterz@infradead.org>
M: Boqun Feng <boqun.feng@gmail.com>
M: Nicholas Piggin <npiggin@gmail.com>
M: David Howells <dhowells@redhat.com>
M: Jade Alglave <j.alglave@ucl.ac.uk>
M: Luc Maranget <luc.maranget@inria.fr>
M: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
The LKMM project already found several bugs in Linux locking
primitives and improved the understanding and the documentation of
the Linux memory model all around.
- Add KASAN instrumentation to atomic APIs (Dmitry Vyukov)
- Add RWSEM API debugging and reorganize the lock debugging Kconfig
(Waiman Long)
- ... misc cleanups and other smaller changes"
* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (31 commits)
locking/Kconfig: Restructure the lock debugging menu
locking/Kconfig: Add LOCK_DEBUGGING_SUPPORT to make it more readable
locking/rwsem: Add DEBUG_RWSEMS to look for lock/unlock mismatches
lockdep: Make the lock debug output more useful
locking/rtmutex: Handle non enqueued waiters gracefully in remove_waiter()
locking/atomic, asm-generic, x86: Add comments for atomic instrumentation
locking/atomic, asm-generic: Add KASAN instrumentation to atomic operations
locking/atomic/x86: Switch atomic.h to use atomic-instrumented.h
locking/atomic, asm-generic: Add asm-generic/atomic-instrumented.h
locking/xchg/alpha: Remove superfluous memory barriers from the _local() variants
tools/memory-model: Finish the removal of rb-dep, smp_read_barrier_depends(), and lockless_dereference()
tools/memory-model: Add documentation of new litmus test
tools/memory-model: Remove mention of docker/gentoo image
locking/memory-barriers: De-emphasize smp_read_barrier_depends() some more
locking/lockdep: Show unadorned pointers
mutex: Drop linkage.h from mutex.h
tools/memory-model: Remove rb-dep, smp_read_barrier_depends, and lockless_dereference
tools/memory-model: Convert underscores to hyphens
tools/memory-model: Add a S lock-based external-view litmus test
tools/memory-model: Add required herd7 version to README file
...
Pull RCU updates from Ingo Molnar:
"The main RCU subsystem changes in this cycle were:
- Miscellaneous fixes, perhaps most notably removing obsolete code
whose only purpose in life was to gather information for the
now-removed RCU debugfs facility. Other notable changes include
removing NO_HZ_FULL_ALL in favor of the nohz_full kernel boot
parameter, minor optimizations for expedited grace periods, some
added tracing, creating an RCU-specific workqueue using Tejun's new
WQ_MEM_RECLAIM flag, and several cleanups to code and comments.
- SRCU cleanups and optimizations.
- Torture-test updates, perhaps most notably the adding of ARMv8
support, but also including numerous cleanups and usability fixes"
* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (37 commits)
rcu: Create RCU-specific workqueues with rescuers
torture: Provide more sensible nreader/nwriter defaults for rcuperf
torture: Grace periods do not piggyback off of themselves
torture: Adjust rcuperf trace processing to allow for workqueues
torture: Default jitter off when running rcuperf
torture: Specify qemu memory size with --memory argument
rcutorture: Add basic ARM64 support to run scripts
rcutorture: Update kvm.sh header comment
rcutorture: Record which grace-period primitives are tested
rcutorture: Re-enable testing of dynamic expediting
rcutorture: Avoid fake-writer use of undefined primitives
rcutorture: Abstract function and module names
rcutorture: Replace multi-instance kzalloc() with kcalloc()
rcu: Remove SRCU throttling
srcu: Remove dead code in srcu_gp_end()
srcu: Reduce scans of srcu_data in counter wrap check
srcu: Prevent sdp->srcu_gp_seq_needed_exp counter wrap
srcu: Abstract function name
rcu: Make expedited RCU CPU selection avoid unnecessary stores
rcu: Trace expedited GP delays due to transitioning CPUs
...
* pm-core:
driver core: Introduce device links reference counting
PM / wakeirq: Add wakeup name to dedicated wake irqs
* pm-sleep:
PM / hibernate: Change message when writing to /sys/power/resume
PM / hibernate: Make passing hibernate offsets more friendly
PCMCIA / PM: Avoid noirq suspend aborts during suspend-to-idle
* acpi-pm:
ACPI / PM: Fix keyboard wakeup from suspend-to-idle on ASUS UX331UA
ACPI / PM: Allow deeper wakeup power states with no _SxD nor _SxW
ACPI / PM: Reduce LPI constraints logging noise
ACPI / PM: Do not reconfigure GPEs for suspend-to-idle
For a rwsem, locking can either be exclusive or shared. The corresponding
exclusive or shared unlock must be used. Otherwise, the protected data
structures may get corrupted or the lock may be in an inconsistent state.
In order to detect such anomaly, a new configuration option DEBUG_RWSEMS
is added which can be enabled to look for such mismatches and print
warnings that that happens.
Signed-off-by: Waiman Long <longman@redhat.com>
Acked-by: Davidlohr Bueso <dave@stgolabs.net>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1522445280-7767-2-git-send-email-longman@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This file is used both for setting the wakeup device without kernel
command line as well as for actually waking the system (when appropriate
swap header is in place).
To avoid confusion on incorrect logs in system log downgrade the
message to debug and make it clearer.
Signed-off-by: Mario Limonciello <mario.limonciello@dell.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Currently the only way to specify a hibernate offset for a
swap file is on the kernel command line.
Add a new /sys/power/resume_offset that lets userspace
specify the offset and disk to use when initiating a hibernate
cycle.
Signed-off-by: Mario Limonciello <mario.limonciello@dell.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This is a cosmetic patch that deals with the address filter structure's
ambiguous fields 'filter' and 'range'. The former stands to mean that the
filter's *action* should be to filter the traces to its address range if
it's set or stop tracing if it's unset. This is confusing and hard on the
eyes, so this patch replaces it with 'action' enum. The 'range' field is
completely redundant (meaning that the filter is an address range as
opposed to a single address trigger), as we can use zero size to mean the
same thing.
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Acked-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: Will Deacon <will.deacon@arm.com>
Link: http://lkml.kernel.org/r/20180329120648.11902-1-alexander.shishkin@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The lock debug output in print_lock() has a few shortcomings:
- It prints the hlock->acquire_ip field in %px and %pS format. That's
redundant information.
- It lacks information about the lock object itself. The lock class is
not helpful to identify a particular instance of a lock.
Change the output so it prints:
- hlock->instance to allow identification of a particular lock instance.
- only the %pS format of hlock->ip_acquire which is sufficient to decode
the actual code line with faddr2line.
The resulting output is:
3 locks held by a.out/31106:
#0: 00000000b0f753ba (&mm->mmap_sem){++++}, at: copy_process.part.41+0x10d5/0x1fe0
#1: 00000000ef64d539 (&mm->mmap_sem/1){+.+.}, at: copy_process.part.41+0x10fe/0x1fe0
#2: 00000000b41a282e (&mapping->i_mmap_rwsem){++++}, at: copy_process.part.41+0x12f2/0x1fe0
[ tglx: Massaged changelog ]
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: David Rientjes <rientjes@google.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: linux-mm@kvack.org
Cc: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/201803271941.GBE57310.tVSOJLQOFFOHFM@I-love.SAKURA.ne.jp
In -RT task_blocks_on_rt_mutex() may return with -EAGAIN due to
(->pi_blocked_on == PI_WAKEUP_INPROGRESS) before it added itself as a
waiter. In such a case remove_waiter() must not be called because without a
waiter it will trigger the BUG_ON() statement.
This was initially reported by Yimin Deng. Thomas Gleixner fixed it then
with an explicit check for waiters before calling remove_waiter().
Instead of an explicit NULL check before calling rt_mutex_top_waiter() make
the function return NULL if there are no waiters. With that fixed the now
pointless NULL check is removed from rt_mutex_slowlock().
Reported-and-debugged-by: Yimin Deng <yimin11.deng@gmail.com>
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/CAAh1qt=DCL9aUXNxanP5BKtiPp3m+qj4yB+gDohhXPVFCxWwzg@mail.gmail.com
Link: https://lkml.kernel.org/r/20180327121438.sss7hxg3crqy4ecd@linutronix.de
Annoyingly, modify_user_hw_breakpoint() unnecessarily complicates the
modification of a breakpoint - simplify it and remove the pointless
local variables.
Also update the stale Docbook while at it.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: <stable@vger.kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull scheduler fixes from Ingo Molnar:
"Two sched debug output related fixes: a console output fix and
formatting fixes"
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/debug: Adjust newlines for better alignment
sched/debug: Fix per-task line continuation for console output
Pull locking fixes from Ingo Molnar:
"Two fixes: tighten up a jump-labels warning to not trigger on certain
modules and fix confusing (and non-existent) mutex API documentation"
* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
jump_label: Disable jump labels in __exit code
locking/mutex: Improve documentation
With the cherry-picked perf/urgent commit merged separately we can now
merge all the fixes without conflicts.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
take both a + and - sign to get to befor and after the symbol address.
But in actuality, the code does not support the minus. This fixes
that issue, and adds a few more selftests to kprobe events.
-----BEGIN PGP SIGNATURE-----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=SWSP
-----END PGP SIGNATURE-----
Merge tag 'trace-v4.16-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull kprobe fixes from Steven Rostedt:
"The documentation for kprobe events says that symbol offets can take
both a + and - sign to get to befor and after the symbol address.
But in actuality, the code does not support the minus. This fixes that
issue, and adds a few more selftests to kprobe events"
* tag 'trace-v4.16-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
selftests: ftrace: Add a testcase for probepoint
selftests: ftrace: Add a testcase for string type with kprobe_event
selftests: ftrace: Add probe event argument syntax testcase
tracing: probeevent: Fix to support minus offset from symbol
When the SCHED_DEADLINE scheduling class increases the CPU utilization, it
should not wait for the rate limit, otherwise it may miss some deadline.
Tests using rt-app on Exynos5422 with up to 10 SCHED_DEADLINE tasks have
shown reductions of even 10% of deadline misses with a negligible
increase of energy consumption (measured through Baylibre Cape).
Signed-off-by: Claudio Scordino <claudio@evidence.eu.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Joel Fernandes <joelaf@google.com>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Cc: linux-pm@vger.kernel.org
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Morten Rasmussen <morten.rasmussen@arm.com>
Cc: Patrick Bellasi <patrick.bellasi@arm.com>
Cc: Todd Kjos <tkjos@android.com>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Link: https://lkml.kernel.org/r/1520937340-2755-1-git-send-email-claudio@evidence.eu.com
