Pull cgroup updates from Tejun Heo:
"Nothing too exciting.
- updates to the pids controller so that pid limit breaches can be
noticed and monitored from userland.
- cleanups and non-critical bug fixes"
* 'for-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
cgroup: remove duplicated include from cgroup.c
cgroup: Use lld instead of ld when printing pids controller events_limit
cgroup: Add pids controller event when fork fails because of pid limit
cgroup: allow NULL return from ss->css_alloc()
cgroup: remove unnecessary 0 check from css_from_id()
cgroup: fix idr leak for the first cgroup root
Pull irq updates from Thomas Gleixner:
"The irq department delivers:
- new core infrastructure to allow better management of multi-queue
devices (interrupt spreading, node aware descriptor allocation ...)
- a new interrupt flow handler to support the new fangled Intel VMD
devices.
- yet another new interrupt controller driver.
- a series of fixes which addresses sparse warnings, missing
includes, missing static declarations etc from Ben Dooks.
- a fix for the error handling in the hierarchical domain allocation
code.
- the usual pile of small updates to core and driver code"
* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (46 commits)
genirq: Fix missing irq allocation affinity hint
irqdomain: Fix irq_domain_alloc_irqs_recursive() error handling
irq/Documentation: Correct result of echnoing 5 to smp_affinity
MAINTAINERS: Remove Jiang Liu from irq domains
genirq/msi: Fix broken debug output
genirq: Add a helper to spread an affinity mask for MSI/MSI-X vectors
genirq/msi: Make use of affinity aware allocations
genirq: Use affinity hint in irqdesc allocation
genirq: Add affinity hint to irq allocation
genirq: Introduce IRQD_AFFINITY_MANAGED flag
genirq/msi: Remove unused MSI_FLAG_IDENTITY_MAP
irqchip/s3c24xx: Fixup IO accessors for big endian
irqchip/exynos-combiner: Fix usage of __raw IO
irqdomain: Fix disposal of mappings for interrupt hierarchies
irqchip/aspeed-vic: Add irq controller for Aspeed
doc/devicetree: Add Aspeed VIC bindings
x86/PCI/VMD: Use untracked irq handler
genirq: Add untracked irq handler
irqchip/mips-gic: Populate irq_domain names
irqchip/gicv3-its: Implement two-level(indirect) device table support
...
Pull timer updates from Thomas Gleixner:
"This update provides the following changes:
- The rework of the timer wheel which addresses the shortcomings of
the current wheel (cascading, slow search for next expiring timer,
etc). That's the first major change of the wheel in almost 20
years since Finn implemted it.
- A large overhaul of the clocksource drivers init functions to
consolidate the Device Tree initialization
- Some more Y2038 updates
- A capability fix for timerfd
- Yet another clock chip driver
- The usual pile of updates, comment improvements all over the place"
* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (130 commits)
tick/nohz: Optimize nohz idle enter
clockevents: Make clockevents_subsys static
clocksource/drivers/time-armada-370-xp: Fix return value check
timers: Implement optimization for same expiry time in mod_timer()
timers: Split out index calculation
timers: Only wake softirq if necessary
timers: Forward the wheel clock whenever possible
timers/nohz: Remove pointless tick_nohz_kick_tick() function
timers: Optimize collect_expired_timers() for NOHZ
timers: Move __run_timers() function
timers: Remove set_timer_slack() leftovers
timers: Switch to a non-cascading wheel
timers: Reduce the CPU index space to 256k
timers: Give a few structs and members proper names
hlist: Add hlist_is_singular_node() helper
signals: Use hrtimer for sigtimedwait()
timers: Remove the deprecated mod_timer_pinned() API
timers, net/ipv4/inet: Initialize connection request timers as pinned
timers, drivers/tty/mips_ejtag: Initialize the poll timer as pinned
timers, drivers/tty/metag_da: Initialize the poll timer as pinned
...
This allows user memory to be written to during the course of a kprobe.
It shouldn't be used to implement any kind of security mechanism
because of TOC-TOU attacks, but rather to debug, divert, and
manipulate execution of semi-cooperative processes.
Although it uses probe_kernel_write, we limit the address space
the probe can write into by checking the space with access_ok.
We do this as opposed to calling copy_to_user directly, in order
to avoid sleeping. In addition we ensure the threads's current fs
/ segment is USER_DS and the thread isn't exiting nor a kernel thread.
Given this feature is meant for experiments, and it has a risk of
crashing the system, and running programs, we print a warning on
when a proglet that attempts to use this helper is installed,
along with the pid and process name.
Signed-off-by: Sargun Dhillon <sargun@sargun.me>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull x86 boot updates from Ingo Molnar:
"The main changes:
- add initial commits to randomize kernel memory section virtual
addresses, enabled via a new kernel option: RANDOMIZE_MEMORY
(Thomas Garnier, Kees Cook, Baoquan He, Yinghai Lu)
- enhance KASLR (RANDOMIZE_BASE) physical memory randomization (Kees
Cook)
- EBDA/BIOS region boot quirk cleanups (Andy Lutomirski, Ingo Molnar)
- misc cleanups/fixes"
* 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/boot: Simplify EBDA-vs-BIOS reservation logic
x86/boot: Clarify what x86_legacy_features.reserve_bios_regions does
x86/boot: Reorganize and clean up the BIOS area reservation code
x86/mm: Do not reference phys addr beyond kernel
x86/mm: Add memory hotplug support for KASLR memory randomization
x86/mm: Enable KASLR for vmalloc memory regions
x86/mm: Enable KASLR for physical mapping memory regions
x86/mm: Implement ASLR for kernel memory regions
x86/mm: Separate variable for trampoline PGD
x86/mm: Add PUD VA support for physical mapping
x86/mm: Update physical mapping variable names
x86/mm: Refactor KASLR entropy functions
x86/KASLR: Fix boot crash with certain memory configurations
x86/boot/64: Add forgotten end of function marker
x86/KASLR: Allow randomization below the load address
x86/KASLR: Extend kernel image physical address randomization to addresses larger than 4G
x86/KASLR: Randomize virtual address separately
x86/KASLR: Clarify identity map interface
x86/boot: Refuse to build with data relocations
x86/KASLR, x86/power: Remove x86 hibernation restrictions
Pull NOHZ updates from Ingo Molnar:
- fix system/idle cputime leaked on cputime accounting (all nohz
configs) (Rik van Riel)
- remove the messy, ad-hoc irqtime account on nohz-full and make it
compatible with CONFIG_IRQ_TIME_ACCOUNTING=y instead (Rik van Riel)
- cleanups (Frederic Weisbecker)
- remove unecessary irq disablement in the irqtime code (Rik van Riel)
* 'timers-nohz-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/cputime: Drop local_irq_save/restore from irqtime_account_irq()
sched/cputime: Reorganize vtime native irqtime accounting headers
sched/cputime: Clean up the old vtime gen irqtime accounting completely
sched/cputime: Replace VTIME_GEN irq time code with IRQ_TIME_ACCOUNTING code
sched/cputime: Count actually elapsed irq & softirq time
Pull scheduler updates from Ingo Molnar:
- introduce and use task_rcu_dereference()/try_get_task_struct() to fix
and generalize task_struct handling (Oleg Nesterov)
- do various per entity load tracking (PELT) fixes and optimizations
(Peter Zijlstra)
- cputime virt-steal time accounting enhancements/fixes (Wanpeng Li)
- introduce consolidated cputime output file cpuacct.usage_all and
related refactorings (Zhao Lei)
- ... plus misc fixes and enhancements
* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/core: Panic on scheduling while atomic bugs if kernel.panic_on_warn is set
sched/cpuacct: Introduce cpuacct.usage_all to show all CPU stats together
sched/cpuacct: Use loop to consolidate code in cpuacct_stats_show()
sched/cpuacct: Merge cpuacct_usage_index and cpuacct_stat_index enums
sched/fair: Rework throttle_count sync
sched/core: Fix sched_getaffinity() return value kerneldoc comment
sched/fair: Reorder cgroup creation code
sched/fair: Apply more PELT fixes
sched/fair: Fix PELT integrity for new tasks
sched/cgroup: Fix cpu_cgroup_fork() handling
sched/fair: Fix PELT integrity for new groups
sched/fair: Fix and optimize the fork() path
sched/cputime: Add steal time support to full dynticks CPU time accounting
sched/cputime: Fix prev steal time accouting during CPU hotplug
KVM: Fix steal clock warp during guest CPU hotplug
sched/debug: Always show 'nr_migrations'
sched/fair: Use task_rcu_dereference()
sched/api: Introduce task_rcu_dereference() and try_get_task_struct()
sched/idle: Optimize the generic idle loop
sched/fair: Fix the wrong throttled clock time for cfs_rq_clock_task()
Pull perf updates from Ingo Molnar:
"With over 300 commits it's been a busy cycle - with most of the work
concentrated on the tooling side (as it should).
The main kernel side enhancements were:
- Add per event callchain limit: Recently we introduced a sysctl to
tune the max-stack for all events for which callchains were
requested:
$ sysctl kernel.perf_event_max_stack
kernel.perf_event_max_stack = 127
Now this patch introduces a way to configure this per event, i.e.
this becomes possible:
$ perf record -e sched:*/max-stack=2/ -e block:*/max-stack=10/ -a
allowing finer tuning of how much buffer space callchains use.
This uses an u16 from the reserved space at the end, leaving
another u16 for future use.
There has been interest in even finer tuning, namely to control the
max stack for kernel and userspace callchains separately. Further
discussion is needed, we may for instance use the remaining u16 for
that and when it is present, assume that the sample_max_stack
introduced in this patch applies for the kernel, and the u16 left
is used for limiting the userspace callchain (Arnaldo Carvalho de
Melo)
- Optimize AUX event (hardware assisted side-band event) delivery
(Kan Liang)
- Rework Intel family name macro usage (this is partially x86 arch
work) (Dave Hansen)
- Refine and fix Intel LBR support (David Carrillo-Cisneros)
- Add support for Intel 'TopDown' events (Andi Kleen)
- Intel uncore PMU driver fixes and enhancements (Kan Liang)
- ... other misc changes.
Here's an incomplete list of the tooling enhancements (but there's
much more, see the shortlog and the git log for details):
- Support cross unwinding, i.e. collecting '--call-graph dwarf'
perf.data files in one machine and then doing analysis in another
machine of a different hardware architecture. This enables, for
instance, to do:
$ perf record -a --call-graph dwarf
on a x86-32 or aarch64 system and then do 'perf report' on it on a
x86_64 workstation (He Kuang)
- Allow reading from a backward ring buffer (one setup via
sys_perf_event_open() with perf_event_attr.write_backward = 1)
(Wang Nan)
- Finish merging initial SDT (Statically Defined Traces) support, see
cset comments for details about how it all works (Masami Hiramatsu)
- Support attaching eBPF programs to tracepoints (Wang Nan)
- Add demangling of symbols in programs written in the Rust language
(David Tolnay)
- Add support for tracepoints in the python binding, including an
example, that sets up and parses sched:sched_switch events,
tools/perf/python/tracepoint.py (Jiri Olsa)
- Introduce --stdio-color to set up the color output mode selection
in 'annotate' and 'report', allowing emit color escape sequences
when redirecting the output of these tools (Arnaldo Carvalho de
Melo)
- Add 'callindent' option to 'perf script -F', to indent the Intel PT
call stack, making this output more ftrace-like (Adrian Hunter,
Andi Kleen)
- Allow dumping the object files generated by llvm when processing
eBPF scriptlet events (Wang Nan)
- Add stackcollapse.py script to help generating flame graphs (Paolo
Bonzini)
- Add --ldlat option to 'perf mem' to specify load latency for loads
event (e.g. cpu/mem-loads/ ) (Jiri Olsa)
- Tooling support for Intel TopDown counters, recently added to the
kernel (Andi Kleen)"
* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (303 commits)
perf tests: Add is_printable_array test
perf tools: Make is_printable_array global
perf script python: Fix string vs byte array resolving
perf probe: Warn unmatched function filter correctly
perf cpu_map: Add more helpers
perf stat: Balance opening and reading events
tools: Copy linux/{hash,poison}.h and check for drift
perf tools: Remove include/linux/list.h from perf's MANIFEST
tools: Copy the bitops files accessed from the kernel and check for drift
Remove: kernel unistd*h files from perf's MANIFEST, not used
perf tools: Remove tools/perf/util/include/linux/const.h
perf tools: Remove tools/perf/util/include/asm/byteorder.h
perf tools: Add missing linux/compiler.h include to perf-sys.h
perf jit: Remove some no-op error handling
perf jit: Add missing curly braces
objtool: Initialize variable to silence old compiler
objtool: Add -I$(srctree)/tools/arch/$(ARCH)/include/uapi
perf record: Add --tail-synthesize option
perf session: Don't warn about out of order event if write_backward is used
perf tools: Enable overwrite settings
...
Pull locking updates from Ingo Molnar:
"The locking tree was busier in this cycle than the usual pattern - a
couple of major projects happened to coincide.
The main changes are:
- implement the atomic_fetch_{add,sub,and,or,xor}() API natively
across all SMP architectures (Peter Zijlstra)
- add atomic_fetch_{inc/dec}() as well, using the generic primitives
(Davidlohr Bueso)
- optimize various aspects of rwsems (Jason Low, Davidlohr Bueso,
Waiman Long)
- optimize smp_cond_load_acquire() on arm64 and implement LSE based
atomic{,64}_fetch_{add,sub,and,andnot,or,xor}{,_relaxed,_acquire,_release}()
on arm64 (Will Deacon)
- introduce smp_acquire__after_ctrl_dep() and fix various barrier
mis-uses and bugs (Peter Zijlstra)
- after discovering ancient spin_unlock_wait() barrier bugs in its
implementation and usage, strengthen its semantics and update/fix
usage sites (Peter Zijlstra)
- optimize mutex_trylock() fastpath (Peter Zijlstra)
- ... misc fixes and cleanups"
* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (67 commits)
locking/atomic: Introduce inc/dec variants for the atomic_fetch_$op() API
locking/barriers, arch/arm64: Implement LDXR+WFE based smp_cond_load_acquire()
locking/static_keys: Fix non static symbol Sparse warning
locking/qspinlock: Use __this_cpu_dec() instead of full-blown this_cpu_dec()
locking/atomic, arch/tile: Fix tilepro build
locking/atomic, arch/m68k: Remove comment
locking/atomic, arch/arc: Fix build
locking/Documentation: Clarify limited control-dependency scope
locking/atomic, arch/rwsem: Employ atomic_long_fetch_add()
locking/atomic, arch/qrwlock: Employ atomic_fetch_add_acquire()
locking/atomic, arch/mips: Convert to _relaxed atomics
locking/atomic, arch/alpha: Convert to _relaxed atomics
locking/atomic: Remove the deprecated atomic_{set,clear}_mask() functions
locking/atomic: Remove linux/atomic.h:atomic_fetch_or()
locking/atomic: Implement atomic{,64,_long}_fetch_{add,sub,and,andnot,or,xor}{,_relaxed,_acquire,_release}()
locking/atomic: Fix atomic64_relaxed() bits
locking/atomic, arch/xtensa: Implement atomic_fetch_{add,sub,and,or,xor}()
locking/atomic, arch/x86: Implement atomic{,64}_fetch_{add,sub,and,or,xor}()
locking/atomic, arch/tile: Implement atomic{,64}_fetch_{add,sub,and,or,xor}()
locking/atomic, arch/sparc: Implement atomic{,64}_fetch_{add,sub,and,or,xor}()
...
Pull RCU updates from Ingo Molnar:
"The main changes in this cycle were:
- documentation updates
- miscellaneous fixes
- minor reorganization of code
- torture-test updates"
* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (30 commits)
rcu: Correctly handle sparse possible cpus
rcu: sysctl: Panic on RCU Stall
rcu: Fix a typo in a comment
rcu: Make call_rcu_tasks() tolerate first call with irqs disabled
rcu: Disable TASKS_RCU for usermode Linux
rcu: No ordering for rcu_assign_pointer() of NULL
rcutorture: Fix error return code in rcu_perf_init()
torture: Inflict default jitter
rcuperf: Don't treat gp_exp mis-setting as a WARN
rcutorture: Drop "-soundhw pcspkr" from x86 boot arguments
rcutorture: Don't specify the cpu type of QEMU on PPC
rcutorture: Make -soundhw a x86 specific option
rcutorture: Use vmlinux as the fallback kernel image
rcutorture/doc: Create initrd using dracut
torture: Stop onoff task if there is only one cpu
torture: Add starvation events to error summary
torture: Break online and offline functions out of torture_onoff()
torture: Forgive lengthy trace dumps and preemption
torture: Remove CONFIG_RCU_TORTURE_TEST_RUNNABLE, simplify code
torture: Simplify code, eliminate RCU_PERF_TEST_RUNNABLE
...
This patch fixes the __output_custom() routine we currently use with
bpf_skb_copy(). I missed that when len is larger than the size of the
current handle, we can issue multiple invocations of copy_func, and
__output_custom() advances destination but also source buffer by the
written amount of bytes. When we have __output_custom(), this is actually
wrong since in that case the source buffer points to a non-linear object,
in our case an skb, which the copy_func helper is supposed to walk.
Therefore, since this is non-linear we thus need to pass the offset into
the helper, so that copy_func can use it for extracting the data from
the source object.
Therefore, adjust the callback signatures properly and pass offset
into the skb_header_pointer() invoked from bpf_skb_copy() callback. The
__DEFINE_OUTPUT_COPY_BODY() is adjusted to accommodate for two things:
i) to pass in whether we should advance source buffer or not; this is
a compile-time constant condition, ii) to pass in the offset for
__output_custom(), which we do with help of __VA_ARGS__, so everything
can stay inlined as is currently. Both changes allow for adapting the
__output_* fast-path helpers w/o extra overhead.
Fixes: 555c8a8623 ("bpf: avoid stack copy and use skb ctx for event output")
Fixes: 7e3f977edd ("perf, events: add non-linear data support for raw records")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
* pm-cpufreq: (41 commits)
Revert "cpufreq: pcc-cpufreq: update default value of cpuinfo_transition_latency"
cpufreq: export cpufreq_driver_resolve_freq()
cpufreq: Disallow ->resolve_freq() for drivers providing ->target_index()
cpufreq: acpi-cpufreq: use cached frequency mapping when possible
cpufreq: schedutil: map raw required frequency to driver frequency
cpufreq: add cpufreq_driver_resolve_freq()
cpufreq: intel_pstate: Check cpuid for MSR_HWP_INTERRUPT
intel_pstate: Update cpu_frequency tracepoint every time
cpufreq: intel_pstate: clean remnant struct element
cpufreq: powernv: Replacing pstate_id with frequency table index
intel_pstate: Fix MSR_CONFIG_TDP_x addressing in core_get_max_pstate()
cpufreq: Reuse new freq-table helpers
cpufreq: Handle sorted frequency tables more efficiently
cpufreq: Drop redundant check from cpufreq_update_current_freq()
intel_pstate: Declare pid_params/pstate_funcs/hwp_active __read_mostly
intel_pstate: add __init/__initdata marker to some functions/variables
intel_pstate: Fix incorrect placement of __initdata
cpufreq: mvebu: fix integer to pointer cast
cpufreq: intel_pstate: Broxton support
cpufreq: conservative: Do not use transition notifications
...
* pm-sleep:
PM / hibernate: Introduce test_resume mode for hibernation
x86 / hibernate: Use hlt_play_dead() when resuming from hibernation
PM / hibernate: Image data protection during restoration
PM / hibernate: Add missing braces in __register_nosave_region()
PM / hibernate: Clean up comments in snapshot.c
PM / hibernate: Clean up function headers in snapshot.c
PM / hibernate: Add missing braces in hibernate_setup()
PM / hibernate: Recycle safe pages after image restoration
PM / hibernate: Simplify mark_unsafe_pages()
PM / hibernate: Do not free preallocated safe pages during image restore
PM / suspend: show workqueue state in suspend flow
PM / sleep: make PM notifiers called symmetrically
PM / sleep: Make pm_prepare_console() return void
PM / Hibernate: Don't let kasan instrument snapshot.c
* pm-tools:
PM / tools: scripts: AnalyzeSuspend v4.2
tools/turbostat: allow user to alter DESTDIR and PREFIX
Here is the big Staging and IIO driver update for 4.8-rc1.
We ended up adding more code than removing, again, but it's not all that
bad. Lots of cleanups all over the staging tree, and new IIO drivers,
full details in the shortlog.
All of these have been in linux-next for a while with no reported issues.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'staging-4.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging
Pull staging and IIO driver updates from Greg KH:
"Here is the big Staging and IIO driver update for 4.8-rc1.
We ended up adding more code than removing, again, but it's not all
that bad. Lots of cleanups all over the staging tree, and new IIO
drivers, full details in the shortlog.
All of these have been in linux-next for a while with no reported
issues"
* tag 'staging-4.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (417 commits)
drivers:iio:accel:mma8452: removed unwanted return statements
drivers:iio:accel:mma8452: added cleanup provision in case of failure.
iio: Add iio.git tree to MAINTAINERS
iio:st_pressure: clean useless static channel initializers
iio:st_pressure:lps22hb: temperature support
iio:st_pressure:lps22hb: open drain support
iio:st_pressure: temperature triggered buffering
iio:st_pressure: document sampling gains
iio:st_pressure: align storagebits on power of 2
iio:st_sensors: align on storagebits boundaries
staging:iio:lis3l02dq drop separate driver
iio: accel: st_accel: Add lis3l02dq support
iio: adc: add missing of_node references to iio_dev
iio: adc: ti-ads1015: add indio_dev->dev.of_node reference
iio: potentiometer: Fix typo in Kconfig
iio: potentiometer: mcp4531: Add device tree binding
iio: potentiometer: mcp4531: Add device tree binding documentation
iio: potentiometer: mcp4531: Add support for MCP454x, MCP456x, MCP464x and MCP466x
iio:imu:mpu6050: icm20608 initial support
iio: adc: max1363: Add device tree binding
...
test_resume mode is to verify if the snapshot data
written to swap device can be successfully restored
to memory. It is useful to ease the debugging process
on hibernation, since this mode can not only bypass
the BIOSes/bootloader, but also the system re-initialization.
To avoid the risk to break the filesystm on persistent storage,
this patch resumes the image with tasks frozen.
For example:
echo test_resume > /sys/power/disk
echo disk > /sys/power/state
[ 187.306470] PM: Image saving progress: 70%
[ 187.395298] PM: Image saving progress: 80%
[ 187.476697] PM: Image saving progress: 90%
[ 187.554641] PM: Image saving done.
[ 187.558896] PM: Wrote 594600 kbytes in 0.90 seconds (660.66 MB/s)
[ 187.566000] PM: S|
[ 187.589742] PM: Basic memory bitmaps freed
[ 187.594694] PM: Checking hibernation image
[ 187.599865] PM: Image signature found, resuming
[ 187.605209] PM: Loading hibernation image.
[ 187.665753] PM: Basic memory bitmaps created
[ 187.691397] PM: Using 3 thread(s) for decompression.
[ 187.691397] PM: Loading and decompressing image data (148650 pages)...
[ 187.889719] PM: Image loading progress: 0%
[ 188.100452] PM: Image loading progress: 10%
[ 188.244781] PM: Image loading progress: 20%
[ 189.057305] PM: Image loading done.
[ 189.068793] PM: Image successfully loaded
Suggested-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Chen Yu <yu.c.chen@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The slow-path frequency transition path is relatively expensive as it
requires waking up a thread to do work. Should support be added for
remote CPU cpufreq updates that is also expensive since it requires an
IPI. These activities should be avoided if they are not necessary.
To that end, calculate the actual driver-supported frequency required by
the new utilization value in schedutil by using the recently added
cpufreq_driver_resolve_freq API. If it is the same as the previously
requested driver frequency then there is no need to continue with the
update assuming the cpu frequency limits have not changed. This will
have additional benefits should the semantics of the rate limit be
changed to apply solely to frequency transitions rather than to
frequency calculations in schedutil.
The last raw required frequency is cached. This allows the driver
frequency lookup to be skipped in the event that the new raw required
frequency matches the last one, assuming a frequency update has not been
forced due to limits changing (indicated by a next_freq value of
UINT_MAX, see sugov_should_update_freq).
Signed-off-by: Steve Muckle <smuckle@linaro.org>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
There is a double fetch problem in audit_log_single_execve_arg()
where we first check the execve(2) argumnets for any "bad" characters
which would require hex encoding and then re-fetch the arguments for
logging in the audit record[1]. Of course this leaves a window of
opportunity for an unsavory application to munge with the data.
This patch reworks things by only fetching the argument data once[2]
into a buffer where it is scanned and logged into the audit
records(s). In addition to fixing the double fetch, this patch
improves on the original code in a few other ways: better handling
of large arguments which require encoding, stricter record length
checking, and some performance improvements (completely unverified,
but we got rid of some strlen() calls, that's got to be a good
thing).
As part of the development of this patch, I've also created a basic
regression test for the audit-testsuite, the test can be tracked on
GitHub at the following link:
* https://github.com/linux-audit/audit-testsuite/issues/25
[1] If you pay careful attention, there is actually a triple fetch
problem due to a strnlen_user() call at the top of the function.
[2] This is a tiny white lie, we do make a call to strnlen_user()
prior to fetching the argument data. I don't like it, but due to the
way the audit record is structured we really have no choice unless we
copy the entire argument at once (which would require a rather
wasteful allocation). The good news is that with this patch the
kernel no longer relies on this strnlen_user() value for anything
beyond recording it in the log, we also update it with a trustworthy
value whenever possible.
Reported-by: Pengfei Wang <wpengfeinudt@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Paul Moore <paul@paul-moore.com>
For forwarding to be effective, XDP programs should be allowed to
rewrite packet data.
This requires that the drivers supporting XDP must all map the packet
memory as TODEVICE or BIDIRECTIONAL before invoking the program.
Signed-off-by: Brenden Blanco <bblanco@plumgrid.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add a new bpf prog type that is intended to run in early stages of the
packet rx path. Only minimal packet metadata will be available, hence a
new context type, struct xdp_md, is exposed to userspace. So far only
expose the packet start and end pointers, and only in read mode.
An XDP program must return one of the well known enum values, all other
return codes are reserved for future use. Unfortunately, this
restriction is hard to enforce at verification time, so take the
approach of warning at runtime when such programs are encountered. Out
of bounds return codes should alias to XDP_ABORTED.
Signed-off-by: Brenden Blanco <bblanco@plumgrid.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
A subsystem may need to store many copies of a bpf program, each
deserving its own reference. Rather than requiring the caller to loop
one by one (with possible mid-loop failure), add a bulk bpf_prog_add
api.
Signed-off-by: Brenden Blanco <bblanco@plumgrid.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
kernel/trace/bpf_trace.c: In function 'bpf_event_output':
kernel/trace/bpf_trace.c:312: error: unknown field 'next' specified in initializer
kernel/trace/bpf_trace.c:312: warning: missing braces around initializer
kernel/trace/bpf_trace.c:312: warning: (near initialization for 'raw.frag.<anonymous>')
Fixes: 555c8a8623 ("bpf: avoid stack copy and use skb ctx for event output")
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
tick_nohz_start_idle is called before checking whether the idle tick can be
stopped. If the tick cannot be stopped, calling tick_nohz_start_idle() is
pointless and just wasting CPU cycles.
Only invoke tick_nohz_start_idle() when can_stop_idle_tick() returns true. A
short one minute observation of the effect on ARM64 shows a reduction of calls
by 1.5% thus optimizing the idle entry sequence.
[tglx: Massaged changelog ]
Co-developed-by: Sanjeev Yadav<sanjeev.yadav@spreadtrum.com>
Signed-off-by: Gaurav Jindal<gaurav.jindal@spreadtrum.com>
Link: http://lkml.kernel.org/r/20160714120416.GB21099@gaurav.jindal@spreadtrum.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The new affinity hint argument of __irq_domain_alloc_irqs() is missing in
irq_reserve_ipi(). Add it.
This fixes the following compilation error:
kernel/irq/ipi.c: In function ‘irq_reserve_ipi’:
kernel/irq/ipi.c:85:9: error: too few arguments to function ‘__irq_domain_alloc_irqs’
virq = __irq_domain_alloc_irqs(domain, virq, nr_irqs, NUMA_NO_NODE,
^
Fixes: 06ee6d571f ("genirq: Add affinity hint to irq allocation")
Signed-off-by: Vincent Stehlé <vincent.stehle@laposte.net>
Cc: linux-pci@vger.kernel.org
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The clockevents_subsys struct is used for sysfs support and
is not declared or used outside the file it is defined in.
Fix the following warning by making it static:
kernel/time/clockevents.c:648:17: warning: symbol 'clockevents_subsys' was not declared. Should it be static?
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Cc: linux-kernel@lists.codethink.co.uk
Link: http://lkml.kernel.org/r/1466178974-7105-1-git-send-email-ben.dooks@codethink.co.uk
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Should have been obvious, only called from bpf() syscall via map_update_elem()
that calls bpf_fd_array_map_update_elem() under RCU read lock and thus this
must also be in GFP_ATOMIC, of course.
Fixes: 3b1efb196e ("bpf, maps: flush own entries on perf map release")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull workqueue fix from Tejun Heo:
"The optimization for setting unbound worker affinity masks collided
with recent scheduler changes triggering warning messages.
This late pull request fixes the bug by removing the optimization"
* 'for-4.7-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
workqueue: Fix setting affinity of unbound worker threads
This work addresses a couple of issues bpf_skb_event_output()
helper currently has: i) We need two copies instead of just a
single one for the skb data when it should be part of a sample.
The data can be non-linear and thus needs to be extracted via
bpf_skb_load_bytes() helper first, and then copied once again
into the ring buffer slot. ii) Since bpf_skb_load_bytes()
currently needs to be used first, the helper needs to see a
constant size on the passed stack buffer to make sure BPF
verifier can do sanity checks on it during verification time.
Thus, just passing skb->len (or any other non-constant value)
wouldn't work, but changing bpf_skb_load_bytes() is also not
the proper solution, since the two copies are generally still
needed. iii) bpf_skb_load_bytes() is just for rather small
buffers like headers, since they need to sit on the limited
BPF stack anyway. Instead of working around in bpf_skb_load_bytes(),
this work improves the bpf_skb_event_output() helper to address
all 3 at once.
We can make use of the passed in skb context that we have in
the helper anyway, and use some of the reserved flag bits as
a length argument. The helper will use the new __output_custom()
facility from perf side with bpf_skb_copy() as callback helper
to walk and extract the data. It will pass the data for setup
to bpf_event_output(), which generates and pushes the raw record
with an additional frag part. The linear data used in the first
frag of the record serves as programmatically defined meta data
passed along with the appended sample.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Split the bpf_perf_event_output() helper as a preparation into
two parts. The new bpf_perf_event_output() will prepare the raw
record itself and test for unknown flags from BPF trace context,
where the __bpf_perf_event_output() does the core work. The
latter will be reused later on from bpf_event_output() directly.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds support for non-linear data on raw records. It
extends raw records to have one or multiple fragments that will
be written linearly into the ring slot, where each fragment can
optionally have a custom callback handler to walk and extract
complex, possibly non-linear data.
If a callback handler is provided for a fragment, then the new
__output_custom() will be used instead of __output_copy() for
the perf_output_sample() part. perf_prepare_sample() does all
the size calculation only once, so perf_output_sample() doesn't
need to redo the same work anymore, meaning real_size and padding
will be cached in the raw record. The raw record becomes 32 bytes
in size without holes; to not increase it further and to avoid
doing unnecessary recalculations in fast-path, we can reuse
next pointer of the last fragment, idea here is borrowed from
ZERO_OR_NULL_PTR(), which should keep the perf_output_sample()
path for PERF_SAMPLE_RAW minimal.
This facility is needed for BPF's event output helper as a first
user that will, in a follow-up, add an additional perf_raw_frag
to its perf_raw_record in order to be able to more efficiently
dump skb context after a linear head meta data related to it.
skbs can be non-linear and thus need a custom output function to
dump buffers. Currently, the skb data needs to be copied twice;
with the help of __output_custom() this work only needs to be
done once. Future users could be things like XDP/BPF programs
that work on different context though and would thus also have
a different callback function.
The few users of raw records are adapted to initialize their frag
data from the raw record itself, no change in behavior for them.
The code is based upon a PoC diff provided by Peter Zijlstra [1].
[1] http://thread.gmane.org/gmane.linux.network/421294
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
On Intel hardware, native_play_dead() uses mwait_play_dead() by
default and only falls back to the other methods if that fails.
That also happens during resume from hibernation, when the restore
(boot) kernel runs disable_nonboot_cpus() to take all of the CPUs
except for the boot one offline.
However, that is problematic, because the address passed to
__monitor() in mwait_play_dead() is likely to be written to in the
last phase of hibernate image restoration and that causes the "dead"
CPU to start executing instructions again. Unfortunately, the page
containing the address in that CPU's instruction pointer may not be
valid any more at that point.
First, that page may have been overwritten with image kernel memory
contents already, so the instructions the CPU attempts to execute may
simply be invalid. Second, the page tables previously used by that
CPU may have been overwritten by image kernel memory contents, so the
address in its instruction pointer is impossible to resolve then.
A report from Varun Koyyalagunta and investigation carried out by
Chen Yu show that the latter sometimes happens in practice.
To prevent it from happening, temporarily change the smp_ops.play_dead
pointer during resume from hibernation so that it points to a special
"play dead" routine which uses hlt_play_dead() and avoids the
inadvertent "revivals" of "dead" CPUs this way.
A slightly unpleasant consequence of this change is that if the
system is hibernated with one or more CPUs offline, it will generally
draw more power after resume than it did before hibernation, because
the physical state entered by CPUs via hlt_play_dead() is higher-power
than the mwait_play_dead() one in the majority of cases. It is
possible to work around this, but it is unclear how much of a problem
that's going to be in practice, so the workaround will be implemented
later if it turns out to be necessary.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=106371
Reported-by: Varun Koyyalagunta <cpudebug@centtech.com>
Original-by: Chen Yu <yu.c.chen@intel.com>
Tested-by: Chen Yu <yu.c.chen@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Unprivileged users can't use hierarchies if they create them as they do not
have privilieges to the root directory.
Which means the only thing a hiearchy created by an unprivileged user
is good for is expanding the number of cgroup links in every css_set,
which is a DOS attack.
We could allow hierarchies to be created in namespaces in the initial
user namespace. Unfortunately there is only a single namespace for
the names of heirarchies, so that is likely to create more confusion
than not.
So do the simple thing and restrict hiearchy creation to the initial
cgroup namespace.
Cc: stable@vger.kernel.org
Fixes: a79a908fd2 ("cgroup: introduce cgroup namespaces")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
In most code paths involving cgroup migration cgroup_threadgroup_rwsem
is taken. There are two exceptions:
- remove_tasks_in_empty_cpuset calls cgroup_transfer_tasks
- vhost_attach_cgroups_work calls cgroup_attach_task_all
With cgroup_threadgroup_rwsem held it is guaranteed that cgroup_post_fork
and copy_cgroup_ns will reference the same css_set from the process calling
fork.
Without such an interlock there process after fork could reference one
css_set from it's new cgroup namespace and another css_set from
task->cgroups, which semantically is nonsensical.
Cc: stable@vger.kernel.org
Fixes: a79a908fd2 ("cgroup: introduce cgroup namespaces")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
If "clone(CLONE_NEWCGROUP...)" is called it results in a nice lockdep
valid splat.
In __cgroup_proc_write the lock ordering is:
cgroup_mutex -- through cgroup_kn_lock_live
cgroup_threadgroup_rwsem
In copy_process the guts of clone the lock ordering is:
cgroup_threadgroup_rwsem -- through threadgroup_change_begin
cgroup_mutex -- through copy_namespaces -- copy_cgroup_ns
lockdep reports some a different call chains for the first ordering of
cgroup_mutex and cgroup_threadgroup_rwsem but it is harder to trace.
This is most definitely deadlock potential under the right
circumstances.
Fix this by by skipping the cgroup_mutex and making the locking in
copy_cgroup_ns mirror the locking in cgroup_post_fork which also runs
during fork under the cgroup_threadgroup_rwsem.
Cc: stable@vger.kernel.org
Fixes: a79a908fd2 ("cgroup: introduce cgroup namespaces")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Straight forward conversion to the state machine. Though the question arises
whether this needs really all these state transitions to work.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160713153337.982013161@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Install the callbacks via the state machine. They are installed at runtime so
smpcfd_prepare_cpu() needs to be invoked by the boot-CPU.
Signed-off-by: Richard Weinberger <richard@nod.at>
[ Added the dropped CPU dying case back in. ]
Signed-off-by: Richard Cochran <rcochran@linutronix.de>
Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Davidlohr Bueso <dave@stgolabs>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160713153337.818376366@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Install the callbacks via the state machine and let the core invoke
the callbacks on the already online CPUs. A lot of code is removed because
the for-loop is used and create_hash_tables() is removed since its purpose
is covered by the startup / teardown hooks.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160713153337.649867675@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
When tearing down, call timers_dead_cpu() before notify_dead().
There is a hidden dependency between:
- timers
- block multiqueue
- rcutree
If timers_dead_cpu() comes later than blk_mq_queue_reinit_notify()
that latter function causes a RCU stall.
Signed-off-by: Richard Cochran <rcochran@linutronix.de>
Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160713153337.566790058@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Split out the clockevents callbacks instead of piggybacking them on
hrtimers.
This gets rid of a POST_DEAD user. See commit:
54e88fad22 ("sched: Make sure timers have migrated before killing the migration_thread")
We just move the callback state to the proper place in the state machine.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160713153337.485419196@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Merge misc fixes from Andrew Morton:
"20 fixes"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
m32r: fix build warning about putc
mm: workingset: printk missing log level, use pr_info()
mm: thp: refix false positive BUG in page_move_anon_rmap()
mm: rmap: call page_check_address() with sync enabled to avoid racy check
mm: thp: move pmd check inside ptl for freeze_page()
vmlinux.lds: account for destructor sections
gcov: add support for gcc version >= 6
mm, meminit: ensure node is online before checking whether pages are uninitialised
mm, meminit: always return a valid node from early_pfn_to_nid
kasan/quarantine: fix bugs on qlist_move_cache()
uapi: export lirc.h header
madvise_free, thp: fix madvise_free_huge_pmd return value after splitting
Revert "scripts/gdb: add documentation example for radix tree"
Revert "scripts/gdb: add a Radix Tree Parser"
scripts/gdb: Perform path expansion to lx-symbol's arguments
scripts/gdb: add constants.py to .gitignore
scripts/gdb: rebuild constants.py on dependancy change
scripts/gdb: silence 'nothing to do' message
kasan: add newline to messages
mm, compaction: prevent VM_BUG_ON when terminating freeing scanner
Pull scheduler fix from Ingo Molnar:
"Fix a CPU hotplug related corruption of the load average that got
introduced in this merge window"
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/core: Correct off by one bug in load migration calculation
Fix the whitespace in the CWD record
Signed-off-by: Steve Grubb <sgrubb@redhat.com>
[PM: fixed subject line]
Signed-off-by: Paul Moore <paul@paul-moore.com>
Paolo pointed out that irqs are already blocked when irqtime_account_irq()
is called. That means there is no reason to call local_irq_save/restore()
again.
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Radim Krcmar <rkrcmar@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wanpeng Li <wanpeng.li@hotmail.com>
Link: http://lkml.kernel.org/r/1468421405-20056-6-git-send-email-fweisbec@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Vtime generic irqtime accounting has been removed but there are a few
remnants to clean up:
* The vtime_accounting_cpu_enabled() check in irq entry was only used
by CONFIG_VIRT_CPU_ACCOUNTING_GEN. We can safely remove it.
* Without the vtime_accounting_cpu_enabled(), we no longer need to
have a vtime_common_account_irq_enter() indirect function.
* Move vtime_account_irq_enter() implementation under
CONFIG_VIRT_CPU_ACCOUNTING_NATIVE which is the last user.
* The vtime_account_user() call was only used on irq entry for
CONFIG_VIRT_CPU_ACCOUNTING_GEN. We can remove that too.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Radim Krcmar <rkrcmar@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wanpeng Li <wanpeng.li@hotmail.com>
Link: http://lkml.kernel.org/r/1468421405-20056-4-git-send-email-fweisbec@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The CONFIG_VIRT_CPU_ACCOUNTING_GEN irq time tracking code does not
appear to currently work right.
On CPUs without nohz_full=, only tick based irq time sampling is
done, which breaks down when dealing with a nohz_idle CPU.
On firewalls and similar systems, no ticks may happen on a CPU for a
while, and the irq time spent may never get accounted properly. This
can cause issues with capacity planning and power saving, which use
the CPU statistics as inputs in decision making.
Remove the VTIME_GEN vtime irq time code, and replace it with the
IRQ_TIME_ACCOUNTING code, when selected as a config option by the user.
Signed-off-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Radim Krcmar <rkrcmar@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wanpeng Li <wanpeng.li@hotmail.com>
Link: http://lkml.kernel.org/r/1468421405-20056-3-git-send-email-fweisbec@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Currently, if there was any irq or softirq time during 'ticks'
jiffies, the entire period will be accounted as irq or softirq
time.
This is inaccurate if only a subset of the time was actually spent
handling irqs, and could conceivably mis-count all of the ticks during
a period as irq time, when there was some irq and some softirq time.
This can actually happen when irqtime_account_process_tick is called
from account_idle_ticks, which can pass a larger number of ticks down
all at once.
Fix this by changing irqtime_account_hi_update(), irqtime_account_si_update(),
and steal_account_process_ticks() to work with cputime_t time units, and
return the amount of time spent in each mode.
Rename steal_account_process_ticks() to steal_account_process_time(), to
reflect that time is now accounted in cputime_t, instead of ticks.
Additionally, have irqtime_account_process_tick() take into account how
much time was spent in each of steal, irq, and softirq time.
The latter could help improve the accuracy of cputime
accounting when returning from idle on a NO_HZ_IDLE CPU.
Properly accounting how much time was spent in hardirq and
softirq time will also allow the NO_HZ_FULL code to re-use
these same functions for hardirq and softirq accounting.
Signed-off-by: Rik van Riel <riel@redhat.com>
[ Make nsecs_to_cputime64() actually return cputime64_t. ]
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Radim Krcmar <rkrcmar@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wanpeng Li <wanpeng.li@hotmail.com>
Link: http://lkml.kernel.org/r/1468421405-20056-2-git-send-email-fweisbec@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Get rid of the prio ordering of the separate notifiers and use a proper state
callback pair.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Nicolas Iooss <nicolas.iooss_linux@m4x.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160713153335.197083890@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Actually a nice symmetric startup/teardown pair which fits properly into
the state machine concept. In the long run we should be able to invoke
the startup callback for the boot CPU via the state machine and get
rid of the init function which invokes it on the boot CPU.
Note: This comes actually before the perf hardware callbacks. In the notifier
model the hardware callbacks have a higher priority than the core
callback. But that's solely for CPU offline so that hardware migration of
events happens before the core is notified about the outgoing CPU.
With the symetric state array model we have the following ordering:
UP: core -> hardware
DOWN: hardware -> core
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Reviewed-by: Sebastian Siewior <bigeasy@linutronix.de>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160713153333.587514098@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
We switched the hotplug machinery to smpboot threads. Early registration of
hotplug callbacks, i.e. from do_pre_smp_initcalls(), happens before the
threads are initialized. Instead of moving the thread init, we simply handle
it in the hotplug code itself and invoke the function directly.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160713153332.896450738@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
New core features
- Selection of the clock source for IIO timestamps. This is done per device
as it makes little sense to have events in one timebase and data timestamped
on another. Biggest reason for this is that we currently use a clock
source which is non monotonic which can result in 'interesting' data sets.
(Includes export for get_monotonic_corse64 which Thomas Gleixner didn't mind
in an earlier version.)
- MAINTAINERS add the git tree to the list for IIO.
New device support + a kind of indirect staging graduation.
* Broadcom iproc-static-adc
- new driver
* mcp4531
- support for MCP454x, MCP456x, MCP464x and MCP466x potentiometers
* mpu6050
- support the IC20608 6 axis motion tracking device
* st-sensors
- support the lis3l02dq + drop the lis3l02dq driver from staging.
The general purpose driver is missing event support, but good to get
rid of this driver which was rather long in the tooth.
New driver features
* ak8975
- Add vid regulator support and refactor handling in general.
- Allow a delay after enabling regulators.
- Runtime and system PM.
* bmg160
- filter frequency control support.
* bmp280
- SPI device support.
- EOC interrupt support for the BMP085
- power management support.
- supply regulator support.
- reset gpio support
- dt bindings for reset gpio and regulators.
- of table to support device tree registration
* max1363
- Device tree bindings.
* mcp4531
- Device tree bindings.
* st-pressure
- temperature channels as part of triggered buffer (previously not due
probably to alignment issues - see below).
- lps22hb open drain interrupt support.
- lps22hb temperature channel support
Cleanups and reworkings.
* numerous ADC drivers
- ensure the iio_dev->dev.of_node is set to the parent dev.of_node so
as to allow client bindings to find the device.
* ak8975
- Fix incorrect handling of missing regulator
- make sure power is down and remove.
* bmp280
- read the calibration data only once as it doesn't change.
* isl29125
- Use a few macros to make code a touch more readable.
* mma8452
- fix a memory leak on error.
- drop an unecessary bit of return value handling.
* potentiometer kconfig
- typo fix.
* st-pressure
- drop some uninformative default assignments of elements of the channel
array structure (aids readability).
* st-sensors
- Harden interrupt handling considerably. These are actually all using
level interrupts, but at least two known boards have them wired to
edge only interrupt chips. Hence a slightly interesting bit of handling
is needed in which we first allow for the easy option (level triggered) and
secondly check the status registers before reenabling edge interrupts and
fall back to a tight loop in the thread until we successfully clear the
interrupt. No harm is done if we never succeed in doing so. It's an odd
patch that has been through a lot of revisions to reach a consensus on how
to handle what is basically broken hardware (which the previous defaults
allowed to kind of work).
- Fix alignment to defined storagebytes boundaries.
- Ensure alignment of power of 2 byte boundaries. This has always in theory
been part of the ABI of IIO, but we missed a few that snuck in that need
fixing. The effect was minor as they were only followed by timestamp
channels which were correctly aligned,
- Add some docs to explain the gain calculations.
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Merge tag 'iio-for-4.8c' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into staging-next
Jonathan writes:
Third set of IIO new device support, features and cleanups for the 4.8 cycle.
New core features
- Selection of the clock source for IIO timestamps. This is done per device
as it makes little sense to have events in one timebase and data timestamped
on another. Biggest reason for this is that we currently use a clock
source which is non monotonic which can result in 'interesting' data sets.
(Includes export for get_monotonic_corse64 which Thomas Gleixner didn't mind
in an earlier version.)
- MAINTAINERS add the git tree to the list for IIO.
New device support + a kind of indirect staging graduation.
* Broadcom iproc-static-adc
- new driver
* mcp4531
- support for MCP454x, MCP456x, MCP464x and MCP466x potentiometers
* mpu6050
- support the IC20608 6 axis motion tracking device
* st-sensors
- support the lis3l02dq + drop the lis3l02dq driver from staging.
The general purpose driver is missing event support, but good to get
rid of this driver which was rather long in the tooth.
New driver features
* ak8975
- Add vid regulator support and refactor handling in general.
- Allow a delay after enabling regulators.
- Runtime and system PM.
* bmg160
- filter frequency control support.
* bmp280
- SPI device support.
- EOC interrupt support for the BMP085
- power management support.
- supply regulator support.
- reset gpio support
- dt bindings for reset gpio and regulators.
- of table to support device tree registration
* max1363
- Device tree bindings.
* mcp4531
- Device tree bindings.
* st-pressure
- temperature channels as part of triggered buffer (previously not due
probably to alignment issues - see below).
- lps22hb open drain interrupt support.
- lps22hb temperature channel support
Cleanups and reworkings.
* numerous ADC drivers
- ensure the iio_dev->dev.of_node is set to the parent dev.of_node so
as to allow client bindings to find the device.
* ak8975
- Fix incorrect handling of missing regulator
- make sure power is down and remove.
* bmp280
- read the calibration data only once as it doesn't change.
* isl29125
- Use a few macros to make code a touch more readable.
* mma8452
- fix a memory leak on error.
- drop an unecessary bit of return value handling.
* potentiometer kconfig
- typo fix.
* st-pressure
- drop some uninformative default assignments of elements of the channel
array structure (aids readability).
* st-sensors
- Harden interrupt handling considerably. These are actually all using
level interrupts, but at least two known boards have them wired to
edge only interrupt chips. Hence a slightly interesting bit of handling
is needed in which we first allow for the easy option (level triggered) and
secondly check the status registers before reenabling edge interrupts and
fall back to a tight loop in the thread until we successfully clear the
interrupt. No harm is done if we never succeed in doing so. It's an odd
patch that has been through a lot of revisions to reach a consensus on how
to handle what is basically broken hardware (which the previous defaults
allowed to kind of work).
- Fix alignment to defined storagebytes boundaries.
- Ensure alignment of power of 2 byte boundaries. This has always in theory
been part of the ABI of IIO, but we missed a few that snuck in that need
fixing. The effect was minor as they were only followed by timestamp
channels which were correctly aligned,
- Add some docs to explain the gain calculations.
Pull perf and timer fixes from Ingo Molnar:
"A fix for a posix CPU timers bug, and a perf printk message fix"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/x86: Fix bogus kernel printk, again
* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
posix_cpu_timer: Exit early when process has been reaped
The move of calc_load_migrate() from CPU_DEAD to CPU_DYING did not take into
account that the function is now called from a thread running on the outgoing
CPU. As a result a cpu unplug leakes a load of 1 into the global load
accounting mechanism.
Fix it by adjusting for the currently running thread which calls
calc_load_migrate().
Reported-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
Cc: rt@linutronix.de
Cc: shreyas@linux.vnet.ibm.com
Fixes: e9cd8fa4fcfd: ("sched/migration: Move calc_load_migrate() into CPU_DYING")
Link: http://lkml.kernel.org/r/alpine.DEB.2.11.1607121744350.4083@nanos
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Xiaolong Ye reported lock debug warnings triggered by the following commit:
8de4a0066106 ("perf/x86: Convert the core to the hotplug state machine")
The bug is the following: the cpuhp_bp_states[] array is cut short when
CONFIG_SMP=n, but the dynamically registered callbacks are stored nevertheless
and happily scribble outside of the array bounds...
We need to store them in case that the state is unregistered so we can invoke
the teardown function. That's independent of CONFIG_SMP. Make sure the array
is large enough.
Reported-by: kernel test robot <xiaolong.ye@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Adam Borowski <kilobyte@angband.pl>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Anna-Maria Gleixner <anna-maria@linutronix.de>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Stephane Eranian <eranian@google.com>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: lkp@01.org
Cc: stable@vger.kernel.org
Cc: tipbuild@zytor.com
Fixes: cff7d378d3 "cpu/hotplug: Convert to a state machine for the control processor"
Link: http://lkml.kernel.org/r/alpine.DEB.2.11.1607122144560.4083@nanos
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The Kconfig currently controlling compilation of this code is:
init/Kconfig:config BPF_SYSCALL
init/Kconfig: bool "Enable bpf() system call"
...meaning that it currently is not being built as a module by anyone.
Lets remove the couple traces of modular infrastructure use, so that
when reading the driver there is no doubt it is builtin-only.
Note that MODULE_ALIAS is a no-op for non-modular code.
We replace module.h with init.h since the file does use __init.
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: netdev@vger.kernel.org
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
If an irq_domain is auto-recursive and irq_domain_alloc_irqs_recursive()
for its parent has returned an error, then do return and avoid calling
irq_domain_free_irqs_recursive() uselessly, because:
- if domain->ops->alloc() had failed for an auto-recursive irq_domain,
then irq_domain_free_irqs_recursive() had already been called;
- if domain->ops->alloc() had failed for a not auto-recursive irq_domain,
then there is nothing to free at all.
Signed-off-by: Alexander Popov <alex.popov@linux.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Link: http://lkml.kernel.org/r/1467505448-2850-1-git-send-email-alex.popov@linux.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Variable "now" seems to be genuinely used unintialized
if branch
if (CPUCLOCK_PERTHREAD(timer->it_clock)) {
is not taken and branch
if (unlikely(sighand == NULL)) {
is taken. In this case the process has been reaped and the timer is marked as
disarmed anyway. So none of the postprocessing of the sample is
required. Return right away.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/20160707223911.GA26483@p183.telecom.by
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This reverts commit 2c95afc1e8.
Stephane reported the following regression:
> Since Andi added:
>
> commit 2c95afc1e8
> Author: Andi Kleen <ak@linux.intel.com>
> Date: Thu Jun 9 06:14:38 2016 -0700
>
> perf/x86/intel, watchdog: Switch NMI watchdog to ref cycles on x86
>
> $ perf stat -e ref-cycles ls
> <not counted> ....
>
> fails systematically because the ref-cycles is now used by the
> watchdog and given this is a system-wide pinned event, it monopolizes
> the fixed counter 2 which is the only counter able to measure this event.
Since the next merge window is near, fix the regression for now
by reverting the commit.
Reported-by: Stephane Eranian <eranian@google.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Currently, a schedule while atomic error prints the stack trace to the
kernel log and the system continue running.
Although it is possible to collect the kernel log messages and analyze
it, often more information are needed. Furthermore, keep the system
running is not always the best choice. For example, when the preempt
count underflows the system will not stop to complain about scheduling
while atomic, so the kernel log can wrap around overwriting the first
stack trace, tuning the analysis even more challenging.
This patch uses the kernel.panic_on_warn sysctl to help out on these
more complex situations.
When kernel.panic_on_warn is set to 1, the kernel will panic() in the
schedule while atomic detection.
The default value of the sysctl is 0, maintaining the current behavior.
Signed-off-by: Daniel Bristot de Oliveira <bristot@redhat.com>
Reviewed-by: Luis Claudio R. Goncalves <lgoncalv@redhat.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luis Claudio R. Goncalves <lgoncalv@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/e8f7b80f353aa22c63bd8557208163989af8493d.1464983675.git.bristot@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Make it possible to protect all pages holding image data during
hibernate image restoration by setting them read-only (so as to
catch attempts to write to those pages after image data have been
stored in them).
This adds overhead to image restoration code (it may cause large
page mappings to be split as a result of page flags changes) and
the errors it protects against should never happen in theory, so
the feature is only active after passing hibernate=protect_image
to the command line of the restore kernel.
Also it only is built if CONFIG_DEBUG_RODATA is set.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
One branch of an if/else statement in __register_nosave_region() is
formatted against the kernel coding style which causes the code to
look slightly odd. To fix that, add missing braces to it.
No functional changes.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Many comments in kernel/power/snapshot.c do not follow the general
comment formatting rules. They look odd, some of them are outdated
too, some are hard to parse and generally difficult to understand.
Clean them up to make them easier to comprehend.
No functional changes.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The formatting of some function headers in kernel/power/snapshot.c
is not consistent with the general kernel coding style and with the
formatting of some other function headers in the same file.
Make all of them follow the same formatting convention.
No functional changes.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Make hibernate_setup() follow the coding style more closely by adding
some missing braces to the if () statement in it.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
In current code, we can get cpuacct data from several files,
but each file has various limitations.
For example:
- We can get CPU usage in user and kernel mode via cpuacct.stat,
but we can't get detailed data about each CPU.
- We can get each CPU's kernel mode usage in cpuacct.usage_percpu_sys,
but we can't get user mode usage data at the same time.
This patch introduces cpuacct.usage_all, to show all detailed CPU
accounting data together:
# cat cpuacct.usage_all
cpu user system
0 3809760299 5807968992
1 3250329855 454612211
..
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/7744460969edd7caaf0e903592ee52353ed9bdd6.1466415271.git.zhaolei@cn.fujitsu.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
In cpuacct_stats_show() we currently we have copies of similar code,
for each cpustat(system/user) variant.
Use a loop instead to consolidate the code. This will also work better
if we extend the CPUACCT_STAT_NSTATS type.
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/b0597d4224655e9f333f1a6224ed9654c7d7d36a.1466415271.git.zhaolei@cn.fujitsu.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
These two types have similar function, no need to separate them.
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/436748885270d64363c7dc67167507d486c2057a.1466415271.git.zhaolei@cn.fujitsu.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
over time there were multiple requests to access different data
structures and fields of task_struct current, so finally add
the helper to access 'current' as-is. Tracing bpf programs will do
the rest of walking the pointers via bpf_probe_read().
Note that current can be null and bpf program has to deal it with,
but even dumb passing null into bpf_probe_read() is still safe.
Suggested-by: Brendan Gregg <brendan.d.gregg@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
The existing optimization for same expiry time in mod_timer() checks whether
the timer expiry time is the same as the new requested expiry time. In the old
timer wheel implementation this does not take the slack batching into account,
neither does the new implementation evaluate whether the new expiry time will
requeue the timer to the same bucket.
To optimize that, we can calculate the resulting bucket and check if the new
expiry time is different from the current expiry time. This calculation
happens outside the base lock held region. If the resulting bucket is the same
we can avoid taking the base lock and requeueing the timer.
If the timer needs to be requeued then we have to check under the base lock
whether the base time has changed between the lockless calculation and taking
the lock. If it has changed we need to recalculate under the lock.
This optimization takes effect for timers which are enqueued into the less
granular wheel levels (1 and above). With a simple test case the functionality
has been verified:
Before After
Match: 5.5% 86.6%
Requeue: 94.5% 13.4%
Recalc: <0.01%
In the non optimized case the timer is requeued in 94.5% of the cases. With
the index optimization in place the requeue rate drops to 13.4%. The case
where the lockless index calculation has to be redone is less than 0.01%.
With a real world test case (networking) we observed the following changes:
Before After
Match: 97.8% 99.7%
Requeue: 2.2% 0.3%
Recalc: <0.001%
That means two percent fewer lock/requeue/unlock operations done in one of
the hot path use cases of timers.
Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Chris Mason <clm@fb.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: George Spelvin <linux@sciencehorizons.net>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Len Brown <lenb@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160704094342.778527749@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
For further optimizations we need to seperate index calculation
from queueing. No functional change.
Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Chris Mason <clm@fb.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: George Spelvin <linux@sciencehorizons.net>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Len Brown <lenb@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160704094342.691159619@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
With the wheel forwading in place and with the HZ=1000 4ms folding we can
avoid running the softirq at all.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Chris Mason <clm@fb.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: George Spelvin <linux@sciencehorizons.net>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Len Brown <lenb@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160704094342.607650550@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The wheel clock is stale when a CPU goes into a long idle sleep. This has the
side effect that timers which are queued end up in the outer wheel levels.
That results in coarser granularity.
To solve this, we keep track of the idle state and forward the wheel clock
whenever possible.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Chris Mason <clm@fb.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: George Spelvin <linux@sciencehorizons.net>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Len Brown <lenb@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160704094342.512039360@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This was a failed attempt to optimize the timer expiry in idle, which was
disabled and never revisited. Remove the cruft.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Chris Mason <clm@fb.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: George Spelvin <linux@sciencehorizons.net>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Len Brown <lenb@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160704094342.431073782@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
After a NOHZ idle sleep the timer wheel must be forwarded to current jiffies.
There might be expired timers so the current code loops and checks the expired
buckets for timers. This can take quite some time for long NOHZ idle periods.
The pending bitmask in the timer base allows us to do a quick search for the
next expiring timer and therefore a fast forward of the base time which
prevents pointless long lasting loops.
For a 3 seconds idle sleep this reduces the catchup time from ~1ms to 5us.
Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Chris Mason <clm@fb.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: George Spelvin <linux@sciencehorizons.net>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Len Brown <lenb@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160704094342.351296290@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Move __run_timers() below __next_timer_interrupt() and next_pending_bucket()
in preparation for __run_timers() NOHZ optimization.
No functional change.
Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Chris Mason <clm@fb.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: George Spelvin <linux@sciencehorizons.net>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Len Brown <lenb@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160704094342.271872665@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
We now have implicit batching in the timer wheel. The slack API is no longer
used, so remove it.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Andrew F. Davis <afd@ti.com>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Chris Mason <clm@fb.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: George Spelvin <linux@sciencehorizons.net>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jaehoon Chung <jh80.chung@samsung.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Len Brown <lenb@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mathias Nyman <mathias.nyman@intel.com>
Cc: Pali Rohár <pali.rohar@gmail.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Sebastian Reichel <sre@kernel.org>
Cc: Ulf Hansson <ulf.hansson@linaro.org>
Cc: linux-block@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-mmc@vger.kernel.org
Cc: linux-pm@vger.kernel.org
Cc: linux-usb@vger.kernel.org
Cc: netdev@vger.kernel.org
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160704094342.189813118@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The current timer wheel has some drawbacks:
1) Cascading:
Cascading can be an unbound operation and is completely pointless in most
cases because the vast majority of the timer wheel timers are canceled or
rearmed before expiration. (They are used as timeout safeguards, not as
real timers to measure time.)
2) No fast lookup of the next expiring timer:
In NOHZ scenarios the first timer soft interrupt after a long NOHZ period
must fast forward the base time to the current value of jiffies. As we
have no way to find the next expiring timer fast, the code loops linearly
and increments the base time one by one and checks for expired timers
in each step. This causes unbound overhead spikes exactly in the moment
when we should wake up as fast as possible.
After a thorough analysis of real world data gathered on laptops,
workstations, webservers and other machines (thanks Chris!) I came to the
conclusion that the current 'classic' timer wheel implementation can be
modified to address the above issues.
The vast majority of timer wheel timers is canceled or rearmed before
expiry. Most of them are timeouts for networking and other I/O tasks. The
nature of timeouts is to catch the exception from normal operation (TCP ack
timed out, disk does not respond, etc.). For these kinds of timeouts the
accuracy of the timeout is not really a concern. Timeouts are very often
approximate worst-case values and in case the timeout fires, we already
waited for a long time and performance is down the drain already.
The few timers which actually expire can be split into two categories:
1) Short expiry times which expect halfways accurate expiry
2) Long term expiry times are inaccurate today already due to the
batching which is done for NOHZ automatically and also via the
set_timer_slack() API.
So for long term expiry timers we can avoid the cascading property and just
leave them in the less granular outer wheels until expiry or
cancelation. Timers which are armed with a timeout larger than the wheel
capacity are no longer cascaded. We expire them with the longest possible
timeout (6+ days). We have not observed such timeouts in our data collection,
but at least we handle them, applying the rule of the least surprise.
To avoid extending the wheel levels for HZ=1000 so we can accomodate the
longest observed timeouts (5 days in the network conntrack code) we reduce the
first level granularity on HZ=1000 to 4ms, which effectively is the same as
the HZ=250 behaviour. From our data analysis there is nothing which relies on
that 1ms granularity and as a side effect we get better batching and timer
locality for the networking code as well.
Contrary to the classic wheel the granularity of the next wheel is not the
capacity of the first wheel. The granularities of the wheels are in the
currently chosen setting 8 times the granularity of the previous wheel.
So for HZ=250 we end up with the following granularity levels:
Level Offset Granularity Range
0 0 4 ms 0 ms - 252 ms
1 64 32 ms 256 ms - 2044 ms (256ms - ~2s)
2 128 256 ms 2048 ms - 16380 ms (~2s - ~16s)
3 192 2048 ms (~2s) 16384 ms - 131068 ms (~16s - ~2m)
4 256 16384 ms (~16s) 131072 ms - 1048572 ms (~2m - ~17m)
5 320 131072 ms (~2m) 1048576 ms - 8388604 ms (~17m - ~2h)
6 384 1048576 ms (~17m) 8388608 ms - 67108863 ms (~2h - ~18h)
7 448 8388608 ms (~2h) 67108864 ms - 536870911 ms (~18h - ~6d)
That's a worst case inaccuracy of 12.5% for the timers which are queued at the
beginning of a level.
So the new wheel concept addresses the old issues:
1) Cascading is avoided completely
2) By keeping the timers in the bucket until expiry/cancelation we can track
the buckets which have timers enqueued in a bucket bitmap and therefore can
look up the next expiring timer very fast and O(1).
A further benefit of the concept is that the slack calculation which is done
on every timer start is no longer necessary because the granularity levels
provide natural batching already.
Our extensive testing with various loads did not show any performance
degradation vs. the current wheel implementation.
This patch does not address the 'fast lookup' issue as we wanted to make sure
that there is no regression introduced by the wheel redesign. The
optimizations are in follow up patches.
This patch contains fixes from Anna-Maria Gleixner and Richard Cochran.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Chris Mason <clm@fb.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: George Spelvin <linux@sciencehorizons.net>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Len Brown <lenb@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160704094342.108621834@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Some of the names in the internal implementation of the timer code
are not longer correct and others are simply too long to type.
Clean it up before we switch the wheel implementation over to
the new scheme.
No functional change.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Chris Mason <clm@fb.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: George Spelvin <linux@sciencehorizons.net>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Len Brown <lenb@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160704094341.948752516@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
We've converted most timeout related syscalls to hrtimers, but
sigtimedwait() did not get this treatment.
Convert it so we get a reasonable accuracy and remove the
user space exposure to the timer wheel properties.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Chris Mason <clm@fb.com>
Cc: Cyril Hrubis <chrubis@suse.cz>
Cc: George Spelvin <linux@sciencehorizons.net>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Len Brown <lenb@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160704094341.787164909@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
We switched all users to initialize the timers as pinned and call
mod_timer(). Remove the now unused timer API function.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Chris Mason <clm@fb.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: George Spelvin <linux@sciencehorizons.net>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Len Brown <lenb@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160704094341.706205231@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
We want to move the timer migration logic from a 'push' to a 'pull' model.
Under the current 'push' model pinned timers are handled via
a runtime API variant: mod_timer_pinned().
The 'pull' model requires us to store the pinned attribute of a timer
in the timer_list structure itself, as a new TIMER_PINNED bit in
timer->flags.
This flag must be set at initialization time and the timer APIs
recognize the flag.
This patch:
- Implements the new flag and associated new-style initialization
methods
- makes mod_timer() recognize new-style pinned timers,
- and adds some migration helper facility to allow
step by step conversion of old-style to new-style
pinned timers.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Chris Mason <clm@fb.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: George Spelvin <linux@sciencehorizons.net>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Len Brown <lenb@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160704094341.049338558@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Fix the following sparse warnings:
kernel/jump_label.c:473:23: warning:
symbol 'jump_label_module_nb' was not declared. Should it be static?
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
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/1466183980-8903-1-git-send-email-weiyj_lk@163.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The following commit:
66eb579e66 ("perf: allow for PMU-specific event filtering")
added the pmu::filter_match() callback. This was intended to
avoid HW constraints on events from resulting in extremely
pessimistic scheduling.
However, pmu::filter_match() is only called for the leader of each event
group. When the leader is a SW event, we do not filter the groups, and
may fail at pmu::add() time, and when this happens we'll give up on
scheduling any event groups later in the list until they are rotated
ahead of the failing group.
This can result in extremely sub-optimal event scheduling behaviour,
e.g. if running the following on a big.LITTLE platform:
$ taskset -c 0 ./perf stat \
-e 'a57{context-switches,armv8_cortex_a57/config=0x11/}' \
-e 'a53{context-switches,armv8_cortex_a53/config=0x11/}' \
ls
<not counted> context-switches (0.00%)
<not counted> armv8_cortex_a57/config=0x11/ (0.00%)
24 context-switches (37.36%)
57589154 armv8_cortex_a53/config=0x11/ (37.36%)
Here the 'a53' event group was always eligible to be scheduled, but
the 'a57' group never eligible to be scheduled, as the task was always
affine to a Cortex-A53 CPU. The SW (group leader) event in the 'a57'
group was eligible, but the HW event failed at pmu::add() time,
resulting in ctx_flexible_sched_in giving up on scheduling further
groups with HW events.
One way of avoiding this is to check pmu::filter_match() on siblings
as well as the group leader. If any of these fail their
pmu::filter_match() call, we must skip the entire group before
attempting to add any events.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Fixes: 66eb579e66 ("perf: allow for PMU-specific event filtering")
Link: http://lkml.kernel.org/r/1465917041-15339-1-git-send-email-mark.rutland@arm.com
[ Small readability edits. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The pv_time_ops structure contains a function pointer for the
"steal_clock" functionality used only by KVM and Xen on ARM. Xen on x86
uses its own mechanism to account for the "stolen" time a thread wasn't
able to run due to hypervisor scheduling.
Add support in Xen arch independent time handling for this feature by
moving it out of the arm arch into drivers/xen and remove the x86 Xen
hack.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Currently ftrace_graph_ent{,_entry} and ftrace_graph_ret{,_entry} struct
can have padding bytes at the end due to alignment in 64-bit data type.
As these data are recorded so frequently, those paddings waste
non-negligible space. As the ring buffer maintains alignment properly
for each architecture, just to remove the extra padding using 'packed'
attribute.
ftrace_graph_ent_entry: 24 -> 20
ftrace_graph_ret_entry: 48 -> 44
Also I moved the 'overrun' field in struct ftrace_graph_ret to minimize
the padding in the middle.
Tested on x86_64 only.
Link: http://lkml.kernel.org/r/1467197808-13578-1-git-send-email-namhyung@kernel.org
Cc: Ingo Molnar <mingo@kernel.org>
Cc: linux-arch@vger.kernel.org
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
The kbuild test robot reported a compile error if HIST_TRIGGERS was
enabled but nothing else that selected TRACING was configured in.
HIST_TRIGGERS should directly select it and not rely on anything else
to do it.
Link: http://lkml.kernel.org/r/57791866.8080505@linux.intel.com
Reported-by: kbuild test robot <fennguang.wu@intel.com>
Fixes: 7ef224d1d0 ("tracing: Add 'hist' event trigger command")
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Linus Torvalds