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2016-08-31platform driver: fix use-after-free in platform_device_del()Jerome Marchand
In platform_device_del(), the device is still used after a call to device_del(). At this point there is no guarantee that the device is still there and there could be a use-after-free access. Move the call to device_remove_properties() before device_del() to fix that. Signed-off-by: Jerome Marchand <jmarchan@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-31driver core: add test of driver remove calls during probeRob Herring
In recent discussions on ksummit-discuss[1], it was suggested to do a sequence of probe, remove, probe for testing driver remove paths. This adds a kconfig option for said test. [1] https://lists.linuxfoundation.org/pipermail/ksummit-discuss/2016-August/003459.html Suggested-by: Arnd Bergmann <arnd@arndb.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Rob Herring <robh@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-31driver core: fix race between creating/querying glue dir and its cleanupMing Lei
The global mutex of 'gdp_mutex' is used to serialize creating/querying glue dir and its cleanup. Turns out it isn't a perfect way because part(kobj_kset_leave()) of the actual cleanup action() is done inside the release handler of the glue dir kobject. That means gdp_mutex has to be held before releasing the last reference count of the glue dir kobject. This patch moves glue dir's cleanup after kobject_del() in device_del() for avoiding the race. Cc: Yijing Wang <wangyijing@huawei.com> Reported-by: Chandra Sekhar Lingutla <clingutla@codeaurora.org> Signed-off-by: Ming Lei <ming.lei@canonical.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-31PM / runtime: Add _rcuidle suffix to allow rpm_idle() use from idlePaul E. McKenney
This commit appends a few _rcuidle suffixes to fix the following RCU-used-from-idle bug: > =============================== > [ INFO: suspicious RCU usage. ] > 4.6.0-rc5-next-20160426+ #1116 Not tainted > ------------------------------- > include/trace/events/rpm.h:95 suspicious rcu_dereference_check() usage! > > other info that might help us debug this: > > > RCU used illegally from idle CPU! > rcu_scheduler_active = 1, debug_locks = 0 > RCU used illegally from extended quiescent state! > 1 lock held by swapper/0/0: > #0: (&(&dev->power.lock)->rlock){-.-...}, at: [<c052cc2c>] __rpm_callback+0x58/0x60 > > stack backtrace: > CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.6.0-rc5-next-20160426+ #1116 > Hardware name: Generic OMAP36xx (Flattened Device Tree) > [<c0110290>] (unwind_backtrace) from [<c010c3a8>] (show_stack+0x10/0x14) > [<c010c3a8>] (show_stack) from [<c047fd68>] (dump_stack+0xb0/0xe4) > [<c047fd68>] (dump_stack) from [<c052d5d0>] (rpm_suspend+0x580/0x768) > [<c052d5d0>] (rpm_suspend) from [<c052ec58>] (__pm_runtime_suspend+0x64/0x84) > [<c052ec58>] (__pm_runtime_suspend) from [<c04bf25c>] (omap2_gpio_prepare_for_idle+0x5c/0x70) > [<c04bf25c>] (omap2_gpio_prepare_for_idle) from [<c0125568>] (omap_sram_idle+0x140/0x244) > [<c0125568>] (omap_sram_idle) from [<c01269dc>] (omap3_enter_idle_bm+0xfc/0x1ec) > [<c01269dc>] (omap3_enter_idle_bm) from [<c0601bdc>] (cpuidle_enter_state+0x80/0x3d4) > [<c0601bdc>] (cpuidle_enter_state) from [<c0183b08>] (cpu_startup_entry+0x198/0x3a0) > [<c0183b08>] (cpu_startup_entry) from [<c0b00c0c>] (start_kernel+0x354/0x3c8) > [<c0b00c0c>] (start_kernel) from [<8000807c>] (0x8000807c) In the immortal words of Steven Rostedt, "*Whack* *Whack* *Whack*!!!" Reported-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Tested-by: Tony Lindgren <tony@atomide.com> Tested-by: Guenter Roeck <linux@roeck-us.net> WhACKED-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-08-31PM / runtime: Add _rcuidle suffix to allow rpm_resume() to be called from idlePaul E. McKenney
This commit applies another _rcuidle suffix to fix an RCU use from idle. > =============================== > [ INFO: suspicious RCU usage. ] > 4.6.0-rc5-next-20160426+ #1122 Not tainted > ------------------------------- > include/trace/events/rpm.h:69 suspicious rcu_dereference_check() usage! > > other info that might help us debug this: > > > RCU used illegally from idle CPU! > rcu_scheduler_active = 1, debug_locks = 0 > RCU used illegally from extended quiescent state! > 1 lock held by swapper/0/0: > #0: (&(&dev->power.lock)->rlock){-.-...}, at: [<c052e3dc>] __pm_runtime_resume+0x3c/0x64 > > stack backtrace: > CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.6.0-rc5-next-20160426+ #1122 > Hardware name: Generic OMAP36xx (Flattened Device Tree) > [<c0110290>] (unwind_backtrace) from [<c010c3a8>] (show_stack+0x10/0x14) > [<c010c3a8>] (show_stack) from [<c047fd68>] (dump_stack+0xb0/0xe4) > [<c047fd68>] (dump_stack) from [<c052e178>] (rpm_resume+0x5cc/0x7f4) > [<c052e178>] (rpm_resume) from [<c052e3ec>] (__pm_runtime_resume+0x4c/0x64) > [<c052e3ec>] (__pm_runtime_resume) from [<c04bf2c4>] (omap2_gpio_resume_after_idle+0x54/0x68) > [<c04bf2c4>] (omap2_gpio_resume_after_idle) from [<c01269dc>] (omap3_enter_idle_bm+0xfc/0x1ec) > [<c01269dc>] (omap3_enter_idle_bm) from [<c060198c>] (cpuidle_enter_state+0x80/0x3d4) > [<c060198c>] (cpuidle_enter_state) from [<c0183b08>] (cpu_startup_entry+0x198/0x3a0) > [<c0183b08>] (cpu_startup_entry) from [<c0b00c0c>] (start_kernel+0x354/0x3c8) > [<c0b00c0c>] (start_kernel) from [<8000807c>] (0x8000807c) Reported-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Tested-by: Tony Lindgren <tony@atomide.com> Tested-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-08-31driver core: Don't leak secondary fwnode on device removalLukas Wunner
If device_add_property_set() is called for a device, a secondary fwnode is allocated and assigned to the device but currently not freed once the device is removed. This can be triggered on Apple Macs if a Thunderbolt device is plugged in on boot since Apple's NHI EFI driver sets a number of properties for that device which are leaked on unplug. Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-08-18regmap: drop cache if the bus transfer errorElaine Zhang
regmap_write ->_regmap_raw_write -->regcache_write first and than use map->bus->write to wirte i2c or spi But if the i2c or spi transfer failed, But the cache is updated, So if I use regmap_read will get the cache data which is not the real register value. Signed-off-by: Elaine Zhang <zhangqing@rock-chips.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2016-08-12PM / Domains: Always enable debugfs support if availableJon Hunter
Debugfs support for PM domains is only enabled if both CONFIG_PM_DEBUG and CONFIG_PM_ADVANCED_DEBUG are enabled. CONFIG_PM_ADVANCED_DEBUG is described as "extra PM attributes in sysfs for low-level debugging/testing" which does not seem related. Given that the debugfs for PM domains only allows users to view the state of the PM domains, always enable debugfs support for PM domains if PM domains and debugfs support is enabled. Signed-off-by: Jon Hunter <jonathanh@nvidia.com> Acked-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-08-09regmap: debugfs: Add support for dumping write only device registersCristian Birsan
Add support for dumping write only device registers in debugfs. This is useful for audio codecs that have write only registers (like WM8731). The logic that decides if a value can be printed is moved to regmap_printable() function to allow for easier future updates. Signed-off-by: Cristian Birsan <cristian.birsan@microchip.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2016-08-09regmap: Add a function to check if a regmap register is cachedCristian Birsan
Add a function to check if a regmap register is cached. This will be used in debugfs to dump the cached values of write only registers. Signed-off-by: Cristian Birsan <cristian.birsan@microchip.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2016-08-05Merge tag 'pm-extra-4.8-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull more power management updates from Rafael Wysocki: "A few more fixes and cleanups in the x86-64 low-level hibernation code, PM core, cpufreq (Kconfig and intel_pstate), and the operating points framework. Specifics: - Prevent the low-level assembly hibernate code on x86-64 from referring to __PAGE_OFFSET directly as a symbol which doesn't work when the kernel identity mapping base is randomized, in which case __PAGE_OFFSET is a variable (Rafael Wysocki). - Avoid selecting CPU_FREQ_STAT by default as the statistics are not required for proper cpufreq operation (Borislav Petkov). - Add Skylake-X and Broadwell-X IDs to the intel_pstate's list of processors where out-of-band (OBB) control of P-states is possible and if that is in use, intel_pstate should not attempt to manage P-states (Srinivas Pandruvada). - Drop some unnecessary checks from the wakeup IRQ handling code in the PM core (Markus Elfring). - Reduce the number operating performance point (OPP) lookups in one of the OPP framework's helper functions (Jisheng Zhang)" * tag 'pm-extra-4.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: x86/power/64: Do not refer to __PAGE_OFFSET from assembly code cpufreq: Do not default-yes CPU_FREQ_STAT cpufreq: intel_pstate: Add more out-of-band IDs PM / OPP: optimize dev_pm_opp_set_rate() performance a bit PM-wakeup: Delete unnecessary checks before three function calls
2016-08-05Merge tag 'rtc-4.8' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux Pull RTC updates from Alexandre Belloni: "RTC for 4.8 Cleanups: - huge cleanup of rtc-generic and char/genrtc this allowed to cleanup rtc-cmos, rtc-sh, rtc-m68k, rtc-powerpc and rtc-parisc - move mn10300 to rtc-cmos Subsystem: - fix wakealarms after hibernate - multiples fixes for rctest - simplify implementations of .read_alarm New drivers: - Maxim MAX6916 Drivers: - ds1307: fix weekday - m41t80: add wakeup support - pcf85063: add support for PCF85063A variant - rv8803: extend i2c fix and other fixes - s35390a: fix alarm reading, this fixes instant reboot after shutdown for QNAP TS-41x - s3c: clock fixes" * tag 'rtc-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux: (65 commits) rtc: rv8803: Clear V1F when setting the time rtc: rv8803: Stop the clock while setting the time rtc: rv8803: Always apply the I²C workaround rtc: rv8803: Fix read day of week rtc: rv8803: Remove the check for valid time rtc: rv8803: Kconfig: Indicate rx8900 support rtc: asm9260: remove .owner field for driver rtc: at91sam9: Fix missing spin_lock_init() rtc: m41t80: add suspend handlers for alarm IRQ rtc: m41t80: make it a real error message rtc: pcf85063: Add support for the PCF85063A device rtc: pcf85063: fix year range rtc: hym8563: in .read_alarm set .tm_sec to 0 to signal minute accuracy rtc: explicitly set tm_sec = 0 for drivers with minute accurancy rtc: s3c: Add s3c_rtc_{enable/disable}_clk in s3c_rtc_setfreq() rtc: s3c: Remove unnecessary call to disable already disabled clock rtc: abx80x: use devm_add_action_or_reset() rtc: m41t80: use devm_add_action_or_reset() rtc: fix a typo and reduce three empty lines to one rtc: s35390a: improve two comments in .set_alarm ...
2016-08-05Merge branches 'pm-sleep', 'pm-cpufreq', 'pm-core' and 'pm-opp'Rafael J. Wysocki
* pm-sleep: x86/power/64: Do not refer to __PAGE_OFFSET from assembly code * pm-cpufreq: cpufreq: Do not default-yes CPU_FREQ_STAT cpufreq: intel_pstate: Add more out-of-band IDs * pm-core: PM-wakeup: Delete unnecessary checks before three function calls * pm-opp: PM / OPP: optimize dev_pm_opp_set_rate() performance a bit
2016-08-04regmap: rbtree: Avoid overlapping nodesLars-Peter Clausen
When searching for a suitable node that should be used for inserting a new register, which does not fall within the range of any existing node, we not only looks for nodes which are directly adjacent to the new register, but for nodes within a certain proximity. This is done to avoid creating lots of small nodes with just a few registers spacing in between, which would increase memory usage as well as tree traversal time. This means there might be multiple node candidates which fall within the proximity range of the new register. If we choose the first node we encounter, under certain register insertion patterns it is possible to end up with overlapping ranges. This will break order in the rbtree and can cause the cached register value to become corrupted. E.g. take the simplified example where the proximity range is 2 and the register insertion sequence is 1, 4, 2, 3, 5. * Insert of register 1 creates a new node, this is the root of the rbtree * Insert of register 4 creates a new node, which is inserted to the right of the root. * Insert of register 2 gets inserted to the first node * Insert of register 3 gets inserted to the first node * Insert of register 5 also gets inserted into the first node since this is the first node encountered and it is within the proximity range. Now there are two overlapping nodes. To avoid this always choose the node that is closest to the new register. This will ensure that nodes will not overlap. The tree traversal is still done as a binary search, we just don't stop at the first node found. So the complexity of the algorithm stays within the same order. Ideally if a new register is in the range of two adjacent blocks those blocks should be merged, but that is a much more invasive change and left for later. The issue was initially introduced in commit 472fdec7380c ("regmap: rbtree: Reduce number of nodes, take 2"), but became much more exposed by commit 6399aea629b0 ("regmap: rbtree: When adding a reg do a bsearch for target node") which changed the order in which nodes are looked-up. Fixes: 6399aea629b0 ("regmap: rbtree: When adding a reg do a bsearch for target node") Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Mark Brown <broonie@kernel.org>
2016-08-02firmware: support loading into a pre-allocated bufferStephen Boyd
Some systems are memory constrained but they need to load very large firmwares. The firmware subsystem allows drivers to request this firmware be loaded from the filesystem, but this requires that the entire firmware be loaded into kernel memory first before it's provided to the driver. This can lead to a situation where we map the firmware twice, once to load the firmware into kernel memory and once to copy the firmware into the final resting place. This creates needless memory pressure and delays loading because we have to copy from kernel memory to somewhere else. Let's add a request_firmware_into_buf() API that allows drivers to request firmware be loaded directly into a pre-allocated buffer. This skips the intermediate step of allocating a buffer in kernel memory to hold the firmware image while it's read from the filesystem. It also requires that drivers know how much memory they'll require before requesting the firmware and negates any benefits of firmware caching because the firmware layer doesn't manage the buffer lifetime. For a 16MB buffer, about half the time is spent performing a memcpy from the buffer to the final resting place. I see loading times go from 0.081171 seconds to 0.047696 seconds after applying this patch. Plus the vmalloc pressure is reduced. This is based on a patch from Vikram Mulukutla on codeaurora.org: https://www.codeaurora.org/cgit/quic/la/kernel/msm-3.18/commit/drivers/base/firmware_class.c?h=rel/msm-3.18&id=0a328c5f6cd999f5c591f172216835636f39bcb5 Link: http://lkml.kernel.org/r/20160607164741.31849-4-stephen.boyd@linaro.org Signed-off-by: Stephen Boyd <stephen.boyd@linaro.org> Cc: Mimi Zohar <zohar@linux.vnet.ibm.com> Cc: Vikram Mulukutla <markivx@codeaurora.org> Cc: Mark Brown <broonie@kernel.org> Cc: Ming Lei <ming.lei@canonical.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-08-02firmware: provide infrastructure to make fw caching optionalVikram Mulukutla
Some low memory systems with complex peripherals cannot afford to have the relatively large firmware images taking up valuable memory during suspend and resume. Change the internal implementation of firmware_class to disallow caching based on a configurable option. In the near future, variants of request_firmware will take advantage of this feature. Link: http://lkml.kernel.org/r/20160607164741.31849-3-stephen.boyd@linaro.org [stephen.boyd@linaro.org: Drop firmware_desc design and use flags] Signed-off-by: Vikram Mulukutla <markivx@codeaurora.org> Signed-off-by: Stephen Boyd <stephen.boyd@linaro.org> Cc: Mimi Zohar <zohar@linux.vnet.ibm.com> Cc: Mark Brown <broonie@kernel.org> Cc: Ming Lei <ming.lei@canonical.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-08-02firmware: consolidate kmap/read/write logicStephen Boyd
Some systems are memory constrained but they need to load very large firmwares. The firmware subsystem allows drivers to request this firmware be loaded from the filesystem, but this requires that the entire firmware be loaded into kernel memory first before it's provided to the driver. This can lead to a situation where we map the firmware twice, once to load the firmware into kernel memory and once to copy the firmware into the final resting place. This design creates needless memory pressure and delays loading because we have to copy from kernel memory to somewhere else. This patch sets adds support to the request firmware API to load the firmware directly into a pre-allocated buffer, skipping the intermediate copying step and alleviating memory pressure during firmware loading. The drawback is that we can't use the firmware caching feature because the memory for the firmware cache is not managed by the firmware layer. This patch (of 3): We use similar structured code to read and write the kmapped firmware pages. The only difference is read copies from the kmap region and write copies to it. Consolidate this into one function to reduce duplication. Link: http://lkml.kernel.org/r/20160607164741.31849-2-stephen.boyd@linaro.org Signed-off-by: Stephen Boyd <stephen.boyd@linaro.org> Cc: Vikram Mulukutla <markivx@codeaurora.org> Cc: Mimi Zohar <zohar@linux.vnet.ibm.com> Cc: Mark Brown <broonie@kernel.org> Cc: Ming Lei <ming.lei@canonical.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-08-02treewide: replace obsolete _refok by __refFabian Frederick
There was only one use of __initdata_refok and __exit_refok __init_refok was used 46 times against 82 for __ref. Those definitions are obsolete since commit 312b1485fb50 ("Introduce new section reference annotations tags: __ref, __refdata, __refconst") This patch removes the following compatibility definitions and replaces them treewide. /* compatibility defines */ #define __init_refok __ref #define __initdata_refok __refdata #define __exit_refok __ref I can also provide separate patches if necessary. (One patch per tree and check in 1 month or 2 to remove old definitions) [akpm@linux-foundation.org: coding-style fixes] Link: http://lkml.kernel.org/r/1466796271-3043-1-git-send-email-fabf@skynet.be Signed-off-by: Fabian Frederick <fabf@skynet.be> Cc: Ingo Molnar <mingo@redhat.com> Cc: Sam Ravnborg <sam@ravnborg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-31Merge tag 'sound-4.8-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound Pull sound updates from Takashi Iwai: "The majority of this update is about ASoC, including a few new drivers, and the rest are mostly minor changes. The only substantial change in ALSA core is about the additional error handling in the compress-offload API. Below are highlights: - Add the error propagating support in compress-offload API - HD-audio: a usual Dell headset fixup, an Intel HDMI/DP fix, and the default mixer setup change ot turn off the loopback - Lots of updates for ASoC Intel drivers, mostly board support and bug fixing, and to the NAU8825 driver - Work on generalizing bits of simple-card to allow more code sharing with the Renesas rsrc-card (which can't use simple-card due to DPCM) - Removal of the Odroid X2 driver due to replacement with simple-card - Support for several new Mediatek platforms and associated boards - New ASoC drivers for Allwinner A10, Analog Devices ADAU7002, Broadcom Cygnus, Cirrus Logic CS35L33 and CS53L30, Maxim MAX8960 and MAX98504, Realtek RT5514 and Wolfson WM8758" * tag 'sound-4.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound: (278 commits) sound: oss: Use kernel_read_file_from_path() for mod_firmware_load() ASoC: Intel: Skylake: Delete an unnecessary check before the function call "release_firmware" ASoC: Intel: Skylake: Fix NULL Pointer exception in dynamic_debug. ASoC: samsung: Specify DMA channels through struct snd_dmaengine_pcm_config ASoC: samsung: Fix error paths in the I2S driver's probe() ASoC: cs53l30: Fix bit shift issue of TDM mode ASoC: cs53l30: Fix a bug for TDM slot location validation ASoC: rockchip: correct the spdif clk ALSA: echoaudio: purge contradictions between dimension matrix members and total number of members ASoC: rsrc-card: use asoc_simple_card_parse_card_name() ASoC: rsrc-card: use asoc_simple_dai instead of rsrc_card_dai ASoC: rsrc-card: use asoc_simple_card_parse_dailink_name() ASoC: simple-card: use asoc_simple_card_parse_card_name() ASoC: simple-card-utils: add asoc_simple_card_parse_card_name() ASoC: simple-card: use asoc_simple_card_parse_dailink_name() ASoC: simple-card-utils: add asoc_simple_card_set_dailink_name() ASoC: nau8825: drop redundant idiom when converting integer to boolean ASoC: nau8825: jack connection decision with different insertion logic ASoC: mediatek: Add HDMI dai-links to the mt8173-rt5650 machine driver ASoC: mediatek: mt2701: fix non static symbol warning ...
2016-07-29regmap: cache: Fix num_reg_defaults computation from reg_defaults_rawMaarten ter Huurne
In 3245d460 (regmap: cache: Fall back to register by register read for cache defaults) non-readable registers are skipped when initializing reg_defaults, but are still included in num_reg_defaults. So there can be uninitialized entries at the end of reg_defaults, which can cause problems when the register cache initializes from the full array. Fixed it by excluding non-readable registers from the count as well. Signed-off-by: Maarten ter Huurne <maarten@treewalker.org> Signed-off-by: Mark Brown <broonie@kernel.org>
2016-07-28mm: track NR_KERNEL_STACK in KiB instead of number of stacksAndy Lutomirski
Currently, NR_KERNEL_STACK tracks the number of kernel stacks in a zone. This only makes sense if each kernel stack exists entirely in one zone, and allowing vmapped stacks could break this assumption. Since frv has THREAD_SIZE < PAGE_SIZE, we need to track kernel stack allocations in a unit that divides both THREAD_SIZE and PAGE_SIZE on all architectures. Keep it simple and use KiB. Link: http://lkml.kernel.org/r/083c71e642c5fa5f1b6898902e1b2db7b48940d4.1468523549.git.luto@kernel.org Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Vladimir Davydov <vdavydov@virtuozzo.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.org> Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com> Reviewed-by: Vladimir Davydov <vdavydov@virtuozzo.com> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-28mm: move most file-based accounting to the nodeMel Gorman
There are now a number of accounting oddities such as mapped file pages being accounted for on the node while the total number of file pages are accounted on the zone. This can be coped with to some extent but it's confusing so this patch moves the relevant file-based accounted. Due to throttling logic in the page allocator for reliable OOM detection, it is still necessary to track dirty and writeback pages on a per-zone basis. [mgorman@techsingularity.net: fix NR_ZONE_WRITE_PENDING accounting] Link: http://lkml.kernel.org/r/1468404004-5085-5-git-send-email-mgorman@techsingularity.net Link: http://lkml.kernel.org/r/1467970510-21195-20-git-send-email-mgorman@techsingularity.net Signed-off-by: Mel Gorman <mgorman@techsingularity.net> Acked-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Hillf Danton <hillf.zj@alibaba-inc.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Rik van Riel <riel@surriel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-28mm: rename NR_ANON_PAGES to NR_ANON_MAPPEDMel Gorman
NR_FILE_PAGES is the number of file pages. NR_FILE_MAPPED is the number of mapped file pages. NR_ANON_PAGES is the number of mapped anon pages. This is unhelpful naming as it's easy to confuse NR_FILE_MAPPED and NR_ANON_PAGES for mapped pages. This patch renames NR_ANON_PAGES so we have NR_FILE_PAGES is the number of file pages. NR_FILE_MAPPED is the number of mapped file pages. NR_ANON_MAPPED is the number of mapped anon pages. Link: http://lkml.kernel.org/r/1467970510-21195-19-git-send-email-mgorman@techsingularity.net Signed-off-by: Mel Gorman <mgorman@techsingularity.net> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Hillf Danton <hillf.zj@alibaba-inc.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Rik van Riel <riel@surriel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-28mm: move page mapped accounting to the nodeMel Gorman
Reclaim makes decisions based on the number of pages that are mapped but it's mixing node and zone information. Account NR_FILE_MAPPED and NR_ANON_PAGES pages on the node. Link: http://lkml.kernel.org/r/1467970510-21195-18-git-send-email-mgorman@techsingularity.net Signed-off-by: Mel Gorman <mgorman@techsingularity.net> Acked-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Hillf Danton <hillf.zj@alibaba-inc.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Rik van Riel <riel@surriel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-28mm, vmscan: move LRU lists to nodeMel Gorman
This moves the LRU lists from the zone to the node and related data such as counters, tracing, congestion tracking and writeback tracking. Unfortunately, due to reclaim and compaction retry logic, it is necessary to account for the number of LRU pages on both zone and node logic. Most reclaim logic is based on the node counters but the retry logic uses the zone counters which do not distinguish inactive and active sizes. It would be possible to leave the LRU counters on a per-zone basis but it's a heavier calculation across multiple cache lines that is much more frequent than the retry checks. Other than the LRU counters, this is mostly a mechanical patch but note that it introduces a number of anomalies. For example, the scans are per-zone but using per-node counters. We also mark a node as congested when a zone is congested. This causes weird problems that are fixed later but is easier to review. In the event that there is excessive overhead on 32-bit systems due to the nodes being on LRU then there are two potential solutions 1. Long-term isolation of highmem pages when reclaim is lowmem When pages are skipped, they are immediately added back onto the LRU list. If lowmem reclaim persisted for long periods of time, the same highmem pages get continually scanned. The idea would be that lowmem keeps those pages on a separate list until a reclaim for highmem pages arrives that splices the highmem pages back onto the LRU. It potentially could be implemented similar to the UNEVICTABLE list. That would reduce the skip rate with the potential corner case is that highmem pages have to be scanned and reclaimed to free lowmem slab pages. 2. Linear scan lowmem pages if the initial LRU shrink fails This will break LRU ordering but may be preferable and faster during memory pressure than skipping LRU pages. Link: http://lkml.kernel.org/r/1467970510-21195-4-git-send-email-mgorman@techsingularity.net Signed-off-by: Mel Gorman <mgorman@techsingularity.net> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Hillf Danton <hillf.zj@alibaba-inc.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Rik van Riel <riel@surriel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-28mm, vmstat: add infrastructure for per-node vmstatsMel Gorman
Patchset: "Move LRU page reclaim from zones to nodes v9" This series moves LRUs from the zones to the node. While this is a current rebase, the test results were based on mmotm as of June 23rd. Conceptually, this series is simple but there are a lot of details. Some of the broad motivations for this are; 1. The residency of a page partially depends on what zone the page was allocated from. This is partially combatted by the fair zone allocation policy but that is a partial solution that introduces overhead in the page allocator paths. 2. Currently, reclaim on node 0 behaves slightly different to node 1. For example, direct reclaim scans in zonelist order and reclaims even if the zone is over the high watermark regardless of the age of pages in that LRU. Kswapd on the other hand starts reclaim on the highest unbalanced zone. A difference in distribution of file/anon pages due to when they were allocated results can result in a difference in again. While the fair zone allocation policy mitigates some of the problems here, the page reclaim results on a multi-zone node will always be different to a single-zone node. it was scheduled on as a result. 3. kswapd and the page allocator scan zones in the opposite order to avoid interfering with each other but it's sensitive to timing. This mitigates the page allocator using pages that were allocated very recently in the ideal case but it's sensitive to timing. When kswapd is allocating from lower zones then it's great but during the rebalancing of the highest zone, the page allocator and kswapd interfere with each other. It's worse if the highest zone is small and difficult to balance. 4. slab shrinkers are node-based which makes it harder to identify the exact relationship between slab reclaim and LRU reclaim. The reason we have zone-based reclaim is that we used to have large highmem zones in common configurations and it was necessary to quickly find ZONE_NORMAL pages for reclaim. Today, this is much less of a concern as machines with lots of memory will (or should) use 64-bit kernels. Combinations of 32-bit hardware and 64-bit hardware are rare. Machines that do use highmem should have relatively low highmem:lowmem ratios than we worried about in the past. Conceptually, moving to node LRUs should be easier to understand. The page allocator plays fewer tricks to game reclaim and reclaim behaves similarly on all nodes. The series has been tested on a 16 core UMA machine and a 2-socket 48 core NUMA machine. The UMA results are presented in most cases as the NUMA machine behaved similarly. pagealloc --------- This is a microbenchmark that shows the benefit of removing the fair zone allocation policy. It was tested uip to order-4 but only orders 0 and 1 are shown as the other orders were comparable. 4.7.0-rc4 4.7.0-rc4 mmotm-20160623 nodelru-v9 Min total-odr0-1 490.00 ( 0.00%) 457.00 ( 6.73%) Min total-odr0-2 347.00 ( 0.00%) 329.00 ( 5.19%) Min total-odr0-4 288.00 ( 0.00%) 273.00 ( 5.21%) Min total-odr0-8 251.00 ( 0.00%) 239.00 ( 4.78%) Min total-odr0-16 234.00 ( 0.00%) 222.00 ( 5.13%) Min total-odr0-32 223.00 ( 0.00%) 211.00 ( 5.38%) Min total-odr0-64 217.00 ( 0.00%) 208.00 ( 4.15%) Min total-odr0-128 214.00 ( 0.00%) 204.00 ( 4.67%) Min total-odr0-256 250.00 ( 0.00%) 230.00 ( 8.00%) Min total-odr0-512 271.00 ( 0.00%) 269.00 ( 0.74%) Min total-odr0-1024 291.00 ( 0.00%) 282.00 ( 3.09%) Min total-odr0-2048 303.00 ( 0.00%) 296.00 ( 2.31%) Min total-odr0-4096 311.00 ( 0.00%) 309.00 ( 0.64%) Min total-odr0-8192 316.00 ( 0.00%) 314.00 ( 0.63%) Min total-odr0-16384 317.00 ( 0.00%) 315.00 ( 0.63%) Min total-odr1-1 742.00 ( 0.00%) 712.00 ( 4.04%) Min total-odr1-2 562.00 ( 0.00%) 530.00 ( 5.69%) Min total-odr1-4 457.00 ( 0.00%) 433.00 ( 5.25%) Min total-odr1-8 411.00 ( 0.00%) 381.00 ( 7.30%) Min total-odr1-16 381.00 ( 0.00%) 356.00 ( 6.56%) Min total-odr1-32 372.00 ( 0.00%) 346.00 ( 6.99%) Min total-odr1-64 372.00 ( 0.00%) 343.00 ( 7.80%) Min total-odr1-128 375.00 ( 0.00%) 351.00 ( 6.40%) Min total-odr1-256 379.00 ( 0.00%) 351.00 ( 7.39%) Min total-odr1-512 385.00 ( 0.00%) 355.00 ( 7.79%) Min total-odr1-1024 386.00 ( 0.00%) 358.00 ( 7.25%) Min total-odr1-2048 390.00 ( 0.00%) 362.00 ( 7.18%) Min total-odr1-4096 390.00 ( 0.00%) 362.00 ( 7.18%) Min total-odr1-8192 388.00 ( 0.00%) 363.00 ( 6.44%) This shows a steady improvement throughout. The primary benefit is from reduced system CPU usage which is obvious from the overall times; 4.7.0-rc4 4.7.0-rc4 mmotm-20160623nodelru-v8 User 189.19 191.80 System 2604.45 2533.56 Elapsed 2855.30 2786.39 The vmstats also showed that the fair zone allocation policy was definitely removed as can be seen here; 4.7.0-rc3 4.7.0-rc3 mmotm-20160623 nodelru-v8 DMA32 allocs 28794729769 0 Normal allocs 48432501431 77227309877 Movable allocs 0 0 tiobench on ext4 ---------------- tiobench is a benchmark that artifically benefits if old pages remain resident while new pages get reclaimed. The fair zone allocation policy mitigates this problem so pages age fairly. While the benchmark has problems, it is important that tiobench performance remains constant as it implies that page aging problems that the fair zone allocation policy fixes are not re-introduced. 4.7.0-rc4 4.7.0-rc4 mmotm-20160623 nodelru-v9 Min PotentialReadSpeed 89.65 ( 0.00%) 90.21 ( 0.62%) Min SeqRead-MB/sec-1 82.68 ( 0.00%) 82.01 ( -0.81%) Min SeqRead-MB/sec-2 72.76 ( 0.00%) 72.07 ( -0.95%) Min SeqRead-MB/sec-4 75.13 ( 0.00%) 74.92 ( -0.28%) Min SeqRead-MB/sec-8 64.91 ( 0.00%) 65.19 ( 0.43%) Min SeqRead-MB/sec-16 62.24 ( 0.00%) 62.22 ( -0.03%) Min RandRead-MB/sec-1 0.88 ( 0.00%) 0.88 ( 0.00%) Min RandRead-MB/sec-2 0.95 ( 0.00%) 0.92 ( -3.16%) Min RandRead-MB/sec-4 1.43 ( 0.00%) 1.34 ( -6.29%) Min RandRead-MB/sec-8 1.61 ( 0.00%) 1.60 ( -0.62%) Min RandRead-MB/sec-16 1.80 ( 0.00%) 1.90 ( 5.56%) Min SeqWrite-MB/sec-1 76.41 ( 0.00%) 76.85 ( 0.58%) Min SeqWrite-MB/sec-2 74.11 ( 0.00%) 73.54 ( -0.77%) Min SeqWrite-MB/sec-4 80.05 ( 0.00%) 80.13 ( 0.10%) Min SeqWrite-MB/sec-8 72.88 ( 0.00%) 73.20 ( 0.44%) Min SeqWrite-MB/sec-16 75.91 ( 0.00%) 76.44 ( 0.70%) Min RandWrite-MB/sec-1 1.18 ( 0.00%) 1.14 ( -3.39%) Min RandWrite-MB/sec-2 1.02 ( 0.00%) 1.03 ( 0.98%) Min RandWrite-MB/sec-4 1.05 ( 0.00%) 0.98 ( -6.67%) Min RandWrite-MB/sec-8 0.89 ( 0.00%) 0.92 ( 3.37%) Min RandWrite-MB/sec-16 0.92 ( 0.00%) 0.93 ( 1.09%) 4.7.0-rc4 4.7.0-rc4 mmotm-20160623 approx-v9 User 645.72 525.90 System 403.85 331.75 Elapsed 6795.36 6783.67 This shows that the series has little or not impact on tiobench which is desirable and a reduction in system CPU usage. It indicates that the fair zone allocation policy was removed in a manner that didn't reintroduce one class of page aging bug. There were only minor differences in overall reclaim activity 4.7.0-rc4 4.7.0-rc4 mmotm-20160623nodelru-v8 Minor Faults 645838 647465 Major Faults 573 640 Swap Ins 0 0 Swap Outs 0 0 DMA allocs 0 0 DMA32 allocs 46041453 44190646 Normal allocs 78053072 79887245 Movable allocs 0 0 Allocation stalls 24 67 Stall zone DMA 0 0 Stall zone DMA32 0 0 Stall zone Normal 0 2 Stall zone HighMem 0 0 Stall zone Movable 0 65 Direct pages scanned 10969 30609 Kswapd pages scanned 93375144 93492094 Kswapd pages reclaimed 93372243 93489370 Direct pages reclaimed 10969 30609 Kswapd efficiency 99% 99% Kswapd velocity 13741.015 13781.934 Direct efficiency 100% 100% Direct velocity 1.614 4.512 Percentage direct scans 0% 0% kswapd activity was roughly comparable. There were differences in direct reclaim activity but negligible in the context of the overall workload (velocity of 4 pages per second with the patches applied, 1.6 pages per second in the baseline kernel). pgbench read-only large configuration on ext4 --------------------------------------------- pgbench is a database benchmark that can be sensitive to page reclaim decisions. This also checks if removing the fair zone allocation policy is safe pgbench Transactions 4.7.0-rc4 4.7.0-rc4 mmotm-20160623 nodelru-v8 Hmean 1 188.26 ( 0.00%) 189.78 ( 0.81%) Hmean 5 330.66 ( 0.00%) 328.69 ( -0.59%) Hmean 12 370.32 ( 0.00%) 380.72 ( 2.81%) Hmean 21 368.89 ( 0.00%) 369.00 ( 0.03%) Hmean 30 382.14 ( 0.00%) 360.89 ( -5.56%) Hmean 32 428.87 ( 0.00%) 432.96 ( 0.95%) Negligible differences again. As with tiobench, overall reclaim activity was comparable. bonnie++ on ext4 ---------------- No interesting performance difference, negligible differences on reclaim stats. paralleldd on ext4 ------------------ This workload uses varying numbers of dd instances to read large amounts of data from disk. 4.7.0-rc3 4.7.0-rc3 mmotm-20160623 nodelru-v9 Amean Elapsd-1 186.04 ( 0.00%) 189.41 ( -1.82%) Amean Elapsd-3 192.27 ( 0.00%) 191.38 ( 0.46%) Amean Elapsd-5 185.21 ( 0.00%) 182.75 ( 1.33%) Amean Elapsd-7 183.71 ( 0.00%) 182.11 ( 0.87%) Amean Elapsd-12 180.96 ( 0.00%) 181.58 ( -0.35%) Amean Elapsd-16 181.36 ( 0.00%) 183.72 ( -1.30%) 4.7.0-rc4 4.7.0-rc4 mmotm-20160623 nodelru-v9 User 1548.01 1552.44 System 8609.71 8515.08 Elapsed 3587.10 3594.54 There is little or no change in performance but some drop in system CPU usage. 4.7.0-rc3 4.7.0-rc3 mmotm-20160623 nodelru-v9 Minor Faults 362662 367360 Major Faults 1204 1143 Swap Ins 22 0 Swap Outs 2855 1029 DMA allocs 0 0 DMA32 allocs 31409797 28837521 Normal allocs 46611853 49231282 Movable allocs 0 0 Direct pages scanned 0 0 Kswapd pages scanned 40845270 40869088 Kswapd pages reclaimed 40830976 40855294 Direct pages reclaimed 0 0 Kswapd efficiency 99% 99% Kswapd velocity 11386.711 11369.769 Direct efficiency 100% 100% Direct velocity 0.000 0.000 Percentage direct scans 0% 0% Page writes by reclaim 2855 1029 Page writes file 0 0 Page writes anon 2855 1029 Page reclaim immediate 771 1628 Sector Reads 293312636 293536360 Sector Writes 18213568 18186480 Page rescued immediate 0 0 Slabs scanned 128257 132747 Direct inode steals 181 56 Kswapd inode steals 59 1131 It basically shows that kswapd was active at roughly the same rate in both kernels. There was also comparable slab scanning activity and direct reclaim was avoided in both cases. There appears to be a large difference in numbers of inodes reclaimed but the workload has few active inodes and is likely a timing artifact. stutter ------- stutter simulates a simple workload. One part uses a lot of anonymous memory, a second measures mmap latency and a third copies a large file. The primary metric is checking for mmap latency. stutter 4.7.0-rc4 4.7.0-rc4 mmotm-20160623 nodelru-v8 Min mmap 16.6283 ( 0.00%) 13.4258 ( 19.26%) 1st-qrtle mmap 54.7570 ( 0.00%) 34.9121 ( 36.24%) 2nd-qrtle mmap 57.3163 ( 0.00%) 46.1147 ( 19.54%) 3rd-qrtle mmap 58.9976 ( 0.00%) 47.1882 ( 20.02%) Max-90% mmap 59.7433 ( 0.00%) 47.4453 ( 20.58%) Max-93% mmap 60.1298 ( 0.00%) 47.6037 ( 20.83%) Max-95% mmap 73.4112 ( 0.00%) 82.8719 (-12.89%) Max-99% mmap 92.8542 ( 0.00%) 88.8870 ( 4.27%) Max mmap 1440.6569 ( 0.00%) 121.4201 ( 91.57%) Mean mmap 59.3493 ( 0.00%) 42.2991 ( 28.73%) Best99%Mean mmap 57.2121 ( 0.00%) 41.8207 ( 26.90%) Best95%Mean mmap 55.9113 ( 0.00%) 39.9620 ( 28.53%) Best90%Mean mmap 55.6199 ( 0.00%) 39.3124 ( 29.32%) Best50%Mean mmap 53.2183 ( 0.00%) 33.1307 ( 37.75%) Best10%Mean mmap 45.9842 ( 0.00%) 20.4040 ( 55.63%) Best5%Mean mmap 43.2256 ( 0.00%) 17.9654 ( 58.44%) Best1%Mean mmap 32.9388 ( 0.00%) 16.6875 ( 49.34%) This shows a number of improvements with the worst-case outlier greatly improved. Some of the vmstats are interesting 4.7.0-rc4 4.7.0-rc4 mmotm-20160623nodelru-v8 Swap Ins 163 502 Swap Outs 0 0 DMA allocs 0 0 DMA32 allocs 618719206 1381662383 Normal allocs 891235743 564138421 Movable allocs 0 0 Allocation stalls 2603 1 Direct pages scanned 216787 2 Kswapd pages scanned 50719775 41778378 Kswapd pages reclaimed 41541765 41777639 Direct pages reclaimed 209159 0 Kswapd efficiency 81% 99% Kswapd velocity 16859.554 14329.059 Direct efficiency 96% 0% Direct velocity 72.061 0.001 Percentage direct scans 0% 0% Page writes by reclaim 6215049 0 Page writes file 6215049 0 Page writes anon 0 0 Page reclaim immediate 70673 90 Sector Reads 81940800 81680456 Sector Writes 100158984 98816036 Page rescued immediate 0 0 Slabs scanned 1366954 22683 While this is not guaranteed in all cases, this particular test showed a large reduction in direct reclaim activity. It's also worth noting that no page writes were issued from reclaim context. This series is not without its hazards. There are at least three areas that I'm concerned with even though I could not reproduce any problems in that area. 1. Reclaim/compaction is going to be affected because the amount of reclaim is no longer targetted at a specific zone. Compaction works on a per-zone basis so there is no guarantee that reclaiming a few THP's worth page pages will have a positive impact on compaction success rates. 2. The Slab/LRU reclaim ratio is affected because the frequency the shrinkers are called is now different. This may or may not be a problem but if it is, it'll be because shrinkers are not called enough and some balancing is required. 3. The anon/file reclaim ratio may be affected. Pages about to be dirtied are distributed between zones and the fair zone allocation policy used to do something very similar for anon. The distribution is now different but not necessarily in any way that matters but it's still worth bearing in mind. VM statistic counters for reclaim decisions are zone-based. If the kernel is to reclaim on a per-node basis then we need to track per-node statistics but there is no infrastructure for that. The most notable change is that the old node_page_state is renamed to sum_zone_node_page_state. The new node_page_state takes a pglist_data and uses per-node stats but none exist yet. There is some renaming such as vm_stat to vm_zone_stat and the addition of vm_node_stat and the renaming of mod_state to mod_zone_state. Otherwise, this is mostly a mechanical patch with no functional change. There is a lot of similarity between the node and zone helpers which is unfortunate but there was no obvious way of reusing the code and maintaining type safety. Link: http://lkml.kernel.org/r/1467970510-21195-2-git-send-email-mgorman@techsingularity.net Signed-off-by: Mel Gorman <mgorman@techsingularity.net> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Rik van Riel <riel@surriel.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Hillf Danton <hillf.zj@alibaba-inc.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Minchan Kim <minchan@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-28PM / OPP: optimize dev_pm_opp_set_rate() performance a bitJisheng Zhang
In dev_pm_opp_set_rate(), _find_opp_table() is called 4 times: once by _get_opp_clk(), once by dev_pm_opp_set_rate() itself, and twice by dev_pm_opp_find_freq_ceil(). If there are several opp_tables in the system, three times of opp table finding is a big waste. This patch reduced the call of _find_opp_table() to twice. Signed-off-by: Jisheng Zhang <jszhang@marvell.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-07-28PM-wakeup: Delete unnecessary checks before three function callsMarkus Elfring
The following functions test whether their argument is NULL and then return immediately. * dev_pm_arm_wake_irq * dev_pm_disarm_wake_irq * wakeup_source_unregister Thus the test around the calls is not needed. This issue was detected by using the Coccinelle software. Signed-off-by: Markus Elfring <elfring@users.sourceforge.net> Acked-by: Pavel Machek <pavel@ucw.cz> [ rjw: Minor whitespace adjustments ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-07-26Merge branch 'akpm' (patches from Andrew)Linus Torvalds
Merge updates from Andrew Morton: - a few misc bits - ocfs2 - most(?) of MM * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (125 commits) thp: fix comments of __pmd_trans_huge_lock() cgroup: remove unnecessary 0 check from css_from_id() cgroup: fix idr leak for the first cgroup root mm: memcontrol: fix documentation for compound parameter mm: memcontrol: remove BUG_ON in uncharge_list mm: fix build warnings in <linux/compaction.h> mm, thp: convert from optimistic swapin collapsing to conservative mm, thp: fix comment inconsistency for swapin readahead functions thp: update Documentation/{vm/transhuge,filesystems/proc}.txt shmem: split huge pages beyond i_size under memory pressure thp: introduce CONFIG_TRANSPARENT_HUGE_PAGECACHE khugepaged: add support of collapse for tmpfs/shmem pages shmem: make shmem_inode_info::lock irq-safe khugepaged: move up_read(mmap_sem) out of khugepaged_alloc_page() thp: extract khugepaged from mm/huge_memory.c shmem, thp: respect MADV_{NO,}HUGEPAGE for file mappings shmem: add huge pages support shmem: get_unmapped_area align huge page shmem: prepare huge= mount option and sysfs knob mm, rmap: account shmem thp pages ...
2016-07-26Merge tag 'regmap-v4.8' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap Pull regmap updates from Mark Brown: "Several small updates and API enhancements: - provide transparent unrolling of bulk writes into individual writes so they can be used with devices without raw formatting. - fix compatibility between I2C controllers supporting block commands and devices with more than 8 bit wide registers. - add some helpers for iopoll-like functionality and workarounds for weird interrupt controllers" * tag 'regmap-v4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap: regmap: add iopoll-like polling macro regmap: Support bulk writes for devices without raw formatting regmap-i2c: Use i2c block command only if register value width is 8 bit regmap: irq: Add support to call client specific pre/post interrupt service regmap: Add file patterns for regmap device tree bindings
2016-07-26Merge tag 'pm-4.8-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull power management updates from Rafael Wysocki: "Again, the majority of changes go into the cpufreq subsystem, but there are no big features this time. The cpufreq changes that stand out somewhat are the governor interface rework and improvements related to the handling of frequency tables. Apart from those, there are fixes and new device/CPU IDs in drivers, cleanups and an improvement of the new schedutil governor. Next, there are some changes in the hibernation core, including a fix for a nasty problem related to the MONITOR/MWAIT usage by CPU offline during resume from hibernation, a few core improvements related to memory management during resume, a couple of additional debug features and cleanups. Finally, we have some fixes and cleanups in the devfreq subsystem, generic power domains framework improvements related to system suspend/resume, support for some new chips in intel_idle and in the power capping RAPL driver, a new version of the AnalyzeSuspend utility and some assorted fixes and cleanups. Specifics: - Rework the cpufreq governor interface to make it more straightforward and modify the conservative governor to avoid using transition notifications (Rafael Wysocki). - Rework the handling of frequency tables by the cpufreq core to make it more efficient (Viresh Kumar). - Modify the schedutil governor to reduce the number of wakeups it causes to occur in cases when the CPU frequency doesn't need to be changed (Steve Muckle, Viresh Kumar). - Fix some minor issues and clean up code in the cpufreq core and governors (Rafael Wysocki, Viresh Kumar). - Add Intel Broxton support to the intel_pstate driver (Srinivas Pandruvada). - Fix problems related to the config TDP feature and to the validity of the MSR_HWP_INTERRUPT register in intel_pstate (Jan Kiszka, Srinivas Pandruvada). - Make intel_pstate update the cpu_frequency tracepoint even if the frequency doesn't change to avoid confusing powertop (Rafael Wysocki). - Clean up the usage of __init/__initdata in intel_pstate, mark some of its internal variables as __read_mostly and drop an unused structure element from it (Jisheng Zhang, Carsten Emde). - Clean up the usage of some duplicate MSR symbols in intel_pstate and turbostat (Srinivas Pandruvada). - Update/fix the powernv, s3c24xx and mvebu cpufreq drivers (Akshay Adiga, Viresh Kumar, Ben Dooks). - Fix a regression (introduced during the 4.5 cycle) in the pcc-cpufreq driver by reverting the problematic commit (Andreas Herrmann). - Add support for Intel Denverton to intel_idle, clean up Broxton support in it and make it explicitly non-modular (Jacob Pan, Jan Beulich, Paul Gortmaker). - Add support for Denverton and Ivy Bridge server to the Intel RAPL power capping driver and make it more careful about the handing of MSRs that may not be present (Jacob Pan, Xiaolong Wang). - Fix resume from hibernation on x86-64 by making the CPU offline during resume avoid using MONITOR/MWAIT in the "play dead" loop which may lead to an inadvertent "revival" of a "dead" CPU and a page fault leading to a kernel crash from it (Rafael Wysocki). - Make memory management during resume from hibernation more straightforward (Rafael Wysocki). - Add debug features that should help to detect problems related to hibernation and resume from it (Rafael Wysocki, Chen Yu). - Clean up hibernation core somewhat (Rafael Wysocki). - Prevent KASAN from instrumenting the hibernation core which leads to large numbers of false-positives from it (James Morse). - Prevent PM (hibernate and suspend) notifiers from being called during the cleanup phase if they have not been called during the corresponding preparation phase which is possible if one of the other notifiers returns an error at that time (Lianwei Wang). - Improve suspend-related debug printout in the tasks freezer and clean up suspend-related console handling (Roger Lu, Borislav Petkov). - Update the AnalyzeSuspend script in the kernel sources to version 4.2 (Todd Brandt). - Modify the generic power domains framework to make it handle system suspend/resume better (Ulf Hansson). - Make the runtime PM framework avoid resuming devices synchronously when user space changes the runtime PM settings for them and improve its error reporting (Rafael Wysocki, Linus Walleij). - Fix error paths in devfreq drivers (exynos, exynos-ppmu, exynos-bus) and in the core, make some devfreq code explicitly non-modular and change some of it into tristate (Bartlomiej Zolnierkiewicz, Peter Chen, Paul Gortmaker). - Add DT support to the generic PM clocks management code and make it export some more symbols (Jon Hunter, Paul Gortmaker). - Make the PCI PM core code slightly more robust against possible driver errors (Andy Shevchenko). - Make it possible to change DESTDIR and PREFIX in turbostat (Andy Shevchenko)" * tag 'pm-4.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (89 commits) Revert "cpufreq: pcc-cpufreq: update default value of cpuinfo_transition_latency" PM / hibernate: Introduce test_resume mode for hibernation cpufreq: export cpufreq_driver_resolve_freq() cpufreq: Disallow ->resolve_freq() for drivers providing ->target_index() PCI / PM: check all fields in pci_set_platform_pm() 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 PM / tools: scripts: AnalyzeSuspend v4.2 x86 / hibernate: Use hlt_play_dead() when resuming from hibernation cpufreq: powernv: Replacing pstate_id with frequency table index intel_pstate: Fix MSR_CONFIG_TDP_x addressing in core_get_max_pstate() 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() ...
2016-07-26mm, rmap: account shmem thp pagesKirill A. Shutemov
Let's add ShmemHugePages and ShmemPmdMapped fields into meminfo and smaps. It indicates how many times we allocate and map shmem THP. NR_ANON_TRANSPARENT_HUGEPAGES is renamed to NR_ANON_THPS. Link: http://lkml.kernel.org/r/1466021202-61880-27-git-send-email-kirill.shutemov@linux.intel.com Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-26memory-hotplug: use zone_can_shift() for sysfs valid_zones attributeReza Arbab
Since zone_can_shift() is being used to validate the target zone during onlining, it should also be used to determine the content of valid_zones. Link: http://lkml.kernel.org/r/1462816419-4479-4-git-send-email-arbab@linux.vnet.ibm.com Signed-off-by: Reza Arbab <arbab@linux.vnet.ibm.com> Reviewd-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Daniel Kiper <daniel.kiper@oracle.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: David Vrabel <david.vrabel@citrix.com> Cc: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: David Rientjes <rientjes@google.com> Cc: Andrew Banman <abanman@sgi.com> Cc: Chen Yucong <slaoub@gmail.com> Cc: Yasunori Goto <y-goto@jp.fujitsu.com> Cc: Zhang Zhen <zhenzhang.zhang@huawei.com> Cc: Shaohua Li <shaohua.li@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-26Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux Pull s390 updates from Martin Schwidefsky: "There are a couple of new things for s390 with this merge request: - a new scheduling domain "drawer" is added to reflect the unusual topology found on z13 machines. Performance tests showed up to 8 percent gain with the additional domain. - the new crc-32 checksum crypto module uses the vector-galois-field multiply and sum SIMD instruction to speed up crc-32 and crc-32c. - proper __ro_after_init support, this requires RO_AFTER_INIT_DATA in the generic vmlinux.lds linker script definitions. - kcov instrumentation support. A prerequisite for that is the inline assembly basic block cleanup, which is the reason for the net/iucv/iucv.c change. - support for 2GB pages is added to the hugetlbfs backend. Then there are two removals: - the oprofile hardware sampling support is dead code and is removed. The oprofile user space uses the perf interface nowadays. - the ETR clock synchronization is removed, this has been superseeded be the STP clock synchronization. And it always has been "interesting" code.. And the usual bug fixes and cleanups" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (82 commits) s390/pci: Delete an unnecessary check before the function call "pci_dev_put" s390/smp: clean up a condition s390/cio/chp : Remove deprecated create_singlethread_workqueue s390/chsc: improve channel path descriptor determination s390/chsc: sanitize fmt check for chp_desc determination s390/cio: make fmt1 channel path descriptor optional s390/chsc: fix ioctl CHSC_INFO_CU command s390/cio/device_ops: fix kernel doc s390/cio: allow to reset channel measurement block s390/console: Make preferred console handling more consistent s390/mm: fix gmap tlb flush issues s390/mm: add support for 2GB hugepages s390: have unique symbol for __switch_to address s390/cpuinfo: show maximum thread id s390/ptrace: clarify bits in the per_struct s390: stack address vs thread_info s390: remove pointless load within __switch_to s390: enable kcov support s390/cpumf: use basic block for ecctr inline assembly s390/hypfs: use basic block for diag inline assembly ...
2016-07-25Merge branches 'pm-core', 'pm-clk', 'pm-domains' and 'pm-pci'Rafael J. Wysocki
* pm-core: PM / runtime: Asynchronous "idle" in pm_runtime_allow() PM / runtime: print error when activating a child to unactive parent * pm-clk: PM / clk: Add support for adding a specific clock from device-tree PM / clk: export symbols for existing pm_clk_<...> API fcns * pm-domains: PM / Domains: Convert pm_genpd_init() to return an error code PM / Domains: Stop/start devices during system PM suspend/resume in genpd PM / Domains: Allow runtime PM during system PM phases PM / Runtime: Avoid resuming devices again in pm_runtime_force_resume() PM / Domains: Remove redundant pm_request_idle() call in genpd PM / Domains: Remove redundant wrapper functions for system PM PM / Domains: Allow genpd to power on during system PM phases * pm-pci: PCI / PM: check all fields in pci_set_platform_pm()
2016-07-24Merge remote-tracking branches 'asoc/topic/cs53l30', 'asoc/topic/cygnus', ↵Mark Brown
'asoc/topic/da7219' and 'asoc/topic/davinci' into asoc-next
2016-07-15Merge remote-tracking branches 'regmap/topic/bulk', 'regmap/topic/i2c', ↵Mark Brown
'regmap/topic/iopoll', 'regmap/topic/irq' and 'regmap/topic/maintainers' into regmap-next
2016-07-02PM / runtime: Asynchronous "idle" in pm_runtime_allow()Rafael J. Wysocki
Arjan reports that it takes a relatively long time to enable runtime PM for multiple devices at system startup, because all writes to the "control" attribute in sysfs are handled synchronously and if the device is suspended as a result of the write, it will block until that operation is complete. That may be avoided by passing the RPM_ASYNC flag to rpm_idle() in pm_runtime_allow() which will make it execute the device's "idle" callback asynchronously, so writes to "control" changing it from "on" to "auto" will return without waiting. Reported-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Kevin Hilman <khilman@baylibre.com>
2016-06-29regmap: Support bulk writes for devices without raw formattingChen-Yu Tsai
When doing a bulk writes from a device which lacks raw I/O support we fall back to doing register at a time reads but we still use the raw formatters in order to render the data into the word size used by the device (since bulk reads still operate on the device word size rather than unsigned ints). This means that devices without raw formatting such as those that provide reg_read() are not supported. Provide handling for them by copying the values read into native endian values of the appropriate size. This complements commit d5b98eb12420 ("regmap: Support bulk reads for devices without raw formatting"). Signed-off-by: Chen-Yu Tsai <wens@csie.org> Signed-off-by: Mark Brown <broonie@kernel.org>
2016-06-29PM / Domains: Convert pm_genpd_init() to return an error codeUlf Hansson
The are already cases when pm_genpd_init() can fail. Currently we hide the failures instead of propagating an error code, which is a better method. Moreover, to prepare for future changes like moving away from using a fixed array-size of the struct genpd_power_state, to instead dynamically allocate data for it, the pm_genpd_init() API needs to be able to return an error code, as allocation can fail. Current users of the pm_genpd_init() is thus requested to start dealing with error codes. In the transition phase, users will have to live with only error messages being printed to log. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Acked-by: Kevin Hilman <khilman@baylibre.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-06-28PM / clk: Add support for adding a specific clock from device-treeJon Hunter
Some drivers using the PM clocks framework need to add specific clocks from device-tree using a name by calling the functions of_clk_get_by_name() and then pm_clk_add_clk(). Rather than having drivers call both functions, add a helper function of_pm_clk_add_clk() that will call these functions so drivers can call a single function to add a specific clock from device-tree. Signed-off-by: Jon Hunter <jonathanh@nvidia.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-06-28PM / runtime: print error when activating a child to unactive parentLinus Walleij
The code currently silently bails out with -EBUSY if you try to activate a child to an inactive parent. This typically happens when you have a runtime suspended parent and runtime resume your child, but forgot to set .ignore_children on the parent to true with pm_suspend_ignore_children(dev). Silently ignoring this error is not good as it gives rise to other strange behaviour like double-resume of devices after silently bailing out of the .runtime_resume() callback. Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-06-26device property: Add function to search for named child of deviceAdam Thomson
For device nodes in both DT and ACPI, it possible to have named child nodes which contain properties (an existing example being gpio-leds). This adds a function to find a named child node for a device which can be used by drivers for property retrieval. For DT data node name matching, of_node_cmp() and similar functions are made available outside of CONFIG_OF block so the new function can reference these for DT and non-DT builds. For ACPI data node name matching, a helper function is also added which returns false if CONFIG_ACPI is not set, otherwise it performs a string comparison on the data node name. This avoids using the acpi_data_node struct for non CONFIG_ACPI builds, which would otherwise cause a build failure. Signed-off-by: Adam Thomson <Adam.Thomson.Opensource@diasemi.com> Acked-by: Sathyanarayana Nujella <sathyanarayana.nujella@intel.com> Acked-by: Rob Herring <robh@kernel.org> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2016-06-22regmap-i2c: Use i2c block command only if register value width is 8 bitGuenter Roeck
Chips with 16-bit registers don't usually work well with I2C block commands. For example, neither the LM75 datasheet nor the TMP102 datasheet mentions block command support, and in fact it does not work for any of those chips. Also, it is not clear how the block command would handle 16-bit SMBus operations in the fist place, since the data format associated with those commands is either little endian or big endian, which requires some kind of conversion to or from host byte order. Only use i2c block commands if both register and value width is 8 bit. Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Mark Brown <broonie@kernel.org>
2016-06-18Merge tag 'driver-core-4.7-rc4' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core fixes from Greg KH: "Here are a small number of debugfs, ISA, and one driver core fix for 4.7-rc4. All of these resolve reported issues. The ISA ones have spent the least amount of time in linux-next, sorry about that, I didn't realize they were regressions that needed to get in now (thanks to Thorsten for the prodding!) but they do all pass the 0-day bot tests. The others have been in linux-next for a while now. Full details about them are in the shortlog below" * tag 'driver-core-4.7-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: isa: Dummy isa_register_driver should return error code isa: Call isa_bus_init before dependent ISA bus drivers register watchdog: ebc-c384_wdt: Allow build for X86_64 iio: stx104: Allow build for X86_64 gpio: Allow PC/104 devices on X86_64 isa: Allow ISA-style drivers on modern systems base: make module_create_drivers_dir race-free debugfs: open_proxy_open(): avoid double fops release debugfs: full_proxy_open(): free proxy on ->open() failure kernel/kcov: unproxify debugfs file's fops
2016-06-17isa: Call isa_bus_init before dependent ISA bus drivers registerWilliam Breathitt Gray
The isa_bus_init function must be called before drivers which utilize the ISA bus driver are registered. A race condition for initilization exists if device_initcall is used (the isa_bus_init callback is placed in the same initcall level as dependent drivers which use module_init). This patch ensures that isa_bus_init is called first by utilizing postcore_initcall in favor of device_initcall. Fixes: a5117ba7da37 ("[PATCH] Driver model: add ISA bus") Cc: Rene Herman <rene.herman@keyaccess.nl> Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-17isa: Allow ISA-style drivers on modern systemsWilliam Breathitt Gray
Several modern devices, such as PC/104 cards, are expected to run on modern systems via an ISA bus interface. Since ISA is a legacy interface for most modern architectures, ISA support should remain disabled in general. Support for ISA-style drivers should be enabled on a per driver basis. To allow ISA-style drivers on modern systems, this patch introduces the ISA_BUS_API and ISA_BUS Kconfig options. The ISA bus driver will now build conditionally on the ISA_BUS_API Kconfig option, which defaults to the legacy ISA Kconfig option. The ISA_BUS Kconfig option allows the ISA_BUS_API Kconfig option to be selected on architectures which do not enable ISA (e.g. X86_64). The ISA_BUS Kconfig option is currently only implemented for X86 architectures. Other architectures may have their own ISA_BUS Kconfig options added as required. Reviewed-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-06-18Merge branches 'pm-opp' and 'pm-cpufreq-fixes'Rafael J. Wysocki
* pm-opp: PM / OPP: Add 'UNKNOWN' status for shared_opp in struct opp_table * pm-cpufreq-fixes: cpufreq: intel_pstate: Adjust _PSS[0] freqeuency if needed
2016-06-16PM / OPP: Add 'UNKNOWN' status for shared_opp in struct opp_tableViresh Kumar
dev_pm_opp_get_sharing_cpus() returns 0 even in the case when the OPP core doesn't know whether or not the table is shared. It works on the majority of platforms, where the OPP table is never created before invoking the function and then -ENODEV is returned by it. But in the case of one platform (Jetson TK1) at least, the situation is a bit different. The OPP table has been created (somehow) before dev_pm_opp_get_sharing_cpus() is called and it returns 0. Its caller treats that as 'the CPUs don't share OPPs' and that leads to degraded performance. Fix this by converting 'shared_opp' in struct opp_table to an enum and making dev_pm_opp_get_sharing_cpus() return -EINVAL in case when the value of that field is "access unknown", so that the caller can handle it accordingly (cpufreq-dt considers that as 'all CPUs share the table', for example). Fixes: 6f707daa3833 "PM / OPP: Add dev_pm_opp_get_sharing_cpus()" Reported-and-tested-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> [ rjw : Subject & changelog ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-06-16PM / Domains: Stop/start devices during system PM suspend/resume in genpdUlf Hansson
Not all subsystems/drivers that manages devices attached to a genpd makes use of the pm_runtime_force_suspend|resume() helper functions to deal with system PM suspend/resume. In cases like these and when genpd's ->stop|start() callbacks are used for the device, invoke the pm_runtime_force_suspend|resume() helper functions from genpd's "noirq" system PM callbacks. In this way we make sure to "stop" the device on suspend and to "start" it on resume. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Kevin Hilman <khilman@baylibre.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>