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2016-10-03Merge tag 'acpi-4.9-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull ACPI updates from Rafael Wysocki: "First off, the ACPICA code in the kernel is updated to upstream revision 20160831 that brings in a few bug fixes and cleanups. In particular, it is possible to mask GPEs now (and the sysfs interface for GPE control is fixed on top of that), problems related to the table loading mechanism are fixed and all code related to FADT version 2 (which has never been part of the ACPI specification) is dropped. On the new features front, there is a new watchdog driver based on the ACPI WDAT (ACPI Watchdog Action Table), needed on some platforms to replace the iTCO watchdog that doesn't work there, and some UART devices get new definitions of built-in properties (to be accessed via the generic device properties API). Also, included is a fix for an ACPI-related PCI resorces allocation issue and a few problems in the EC driver and in the button and battery drivers are fixed. In addition to that, the ACPI CPPC library is updated to make batching of requests sent over the PCC channel possible (which reduces the PCC usage overhead substantially in some cases) and to support functional fixed hardware (FFH) type of CPPC registers access (which will allow CPPC to be used on x86 too in the future). As usual, there are some assorted fixes and cleanups too. Specifics: - Update of the ACPICA code in the kernel to upstream revision 20160831 with the following major changes: * New mechanism for GPE masking. * Fixes for issues related to the LoadTable operator and table loading. * Fixes for issues related to so-called module-level code (MLC), that is AML that doesn't belong to any methods. * Change of the return value of the _OSI method to reflect the Windows behavior. * GAS (Generic Address Structure) support fix related to 32-bit FADT addresses. * Elimination of unnecessary FADT version 2 support. * ACPI tools fixes and cleanups. From Bob Moore, Lv Zheng, and Jung-uk Kim. - ACPI sysfs interface updates to fix GPE handling (on top of the new GPE masking mechanism in ACPICA) and issues related to table loading (Lv Zheng). - New watchdog driver based on the ACPI WDAT (ACPI Watchdog Action Table), needed on some platforms to replace the iTCO watchdog that doesn't work there and related updates of the intel_pmc_ipc, i2c/i801 and MFD/lcp_ich drivers (Mika Westerberg). - Driver core fix to prevent it from leaking secondary fwnode objects during device removal (Lukas Wunner). - New definitions of built-in properties for UART in ACPI-based x86 SoC drivers and a 8250_dw driver quirk for the APM X-Gene SoC (Heikki Krogerus). - New device ID for the Vulcan SPI controller and constification of local strucures in the AMD SoC (APD) ACPI driver (Kamlakant Patel, Julia Lawall). - Fix for a bug causing the allocation of PCI resorces to fail if ACPI-enumerated child platform devices are registered below the PCI devices in question (Mika Westerberg). - Change of the default polarity for PCI legacy IRQs to high on systems booting wth ACPI on platforms with a GIC interrupt controller model fixing the discrepancy between the specification and HW behavior (Lorenzo Pieralisi). - Fixes for the handling of system suspend/resume in the ACPI EC driver and update of that driver to make it cope with the cases when the EC device defined in the ECDT has to be used throughout the entire system life cycle (Lv Zheng). - Update of the ACPI CPPC library to allow it to batch requests sent over the PCC channel (to reduce overhead), to support the fixed functional hardware (FFH) CPPC registers access type, to notify the mailbox framework about TX completions when the interrupt flag is set for the PCC mailbox, and to support HW-Reduced Communication Subspace type 2 (Ashwin Chaugule, Prashanth Prakash, Srinivas Pandruvada, Hoan Tran). - ACPI button driver fix and documentation update related to the handling of laptop lids (Lv Zheng). - ACPI battery driver initialization fix (Carlos Garnacho). - ACPI GPIO enumeration documentation update (Mika Westerberg). - Assorted updates of the core ACPI bus type code (Lukas Wunner, Lv Zheng). - Assorted cleanups of the ACPI table parsing code and the x86-specific ACPI code (Al Stone). - Fixes for assorted ACPI-related issues found in linux-next (Wei Yongjun)" * tag 'acpi-4.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (98 commits) ACPI / documentation: Use recommended name in GPIO property names watchdog: wdat_wdt: Fix warning for using 0 as NULL watchdog: wdat_wdt: fix return value check in wdat_wdt_probe() platform/x86: intel_pmc_ipc: Do not create iTCO watchdog when WDAT table exists i2c: i801: Do not create iTCO watchdog when WDAT table exists mfd: lpc_ich: Do not create iTCO watchdog when WDAT table exists ACPI / bus: Adjust ACPI subsystem initialization for new table loading mode ACPICA: Parser: Fix a regression in LoadTable support ACPICA: Tables: Fix "UNLOAD" code path lock issues ACPI / watchdog: Add support for WDAT hardware watchdog ACPI / platform: Pay attention to parent device's resources PCI: Add pci_find_resource() ACPI / CPPC: Support PCC with interrupt flag ACPI / sysfs: Update sysfs signature handling code ACPI / sysfs: Fix an issue for LoadTable opcode ACPICA: Tables: Fix a regression in acpi_tb_find_table() ACPI / tables: Remove duplicated include from tables.c ACPI / APD: constify local structures x86: ACPI: make variable names clearer in acpi_parse_madt_lapic_entries() x86: ACPI: remove extraneous white space after semicolon ...
2016-10-01Merge branches 'pm-cpuidle', 'pm-opp' and 'pm-avs'Rafael J. Wysocki
* pm-cpuidle: ARM: cpuidle: Fix error return code * pm-opp: PM / OPP: Don't support OPP if it provides supported-hw but platform does not PM / OPP: avoid maybe-uninitialized warning * pm-avs: PM / AVS: SmartReflex: Neaten logging
2016-10-01Merge branch 'pm-domains'Rafael J. Wysocki
* pm-domains: PM / Domains: Rename pm_genpd_sync_poweron|poweroff() PM / Domains: Don't measure latency of ->power_on|off() during system PM PM / Domains: Remove redundant system PM callbacks PM / Domains: Simplify detaching a device from its genpd PM / Domains: Allow holes in genpd_data.domains array PM / Domains: Add support for removing nested PM domains by provider PM / Domains: Add support for removing PM domains PM / Domains: Store the provider in the PM domain structure PM / Domains: Prepare for adding support to remove PM domains PM / Domains: Verify the PM domain is present when adding a provider PM / Domains: Don't expose xlate and provider helper functions PM / Domains: Don't expose generic_pm_domain structure to clients staging: board: Remove calls to of_genpd_get_from_provider() ARM: EXYNOS: Remove calls to of_genpd_get_from_provider() PM / Domains: Add new helper functions for device-tree PM / Domains: Always enable debugfs support if available
2016-10-01Merge branch 'device-properties'Rafael J. Wysocki
* device-properties: serial: 8250_dw: Add quirk for APM X-Gene SoC ACPI / LPSS: Provide build-in properties of the UART ACPI / APD: Provide build-in properties of the UART driver core: Don't leak secondary fwnode on device removal
2016-09-26PM / OPP: Don't support OPP if it provides supported-hw but platform does notDave Gerlach
The OPP framework allows each OPP to set a opp-supported-hw property which provides values that are matched against supported_hw values provided by the platform to limit support for certain OPPs on specific hardware. Currently, if the platform does not set supported_hw values, all OPPs are interpreted as supported, even if they have provided their own opp-supported-hw values. If an OPP has provided opp-supported-hw, it is indicating that there is some specific hardware configuration it is supported by. These constraints should be honored, and if no supported_hw has been provided by the platform, there is no way to determine if that OPP is actually supported, so it should be marked as not supported. Signed-off-by: Dave Gerlach <d-gerlach@ti.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-09-23PM / Domains: Rename pm_genpd_sync_poweron|poweroff()Ulf Hansson
These are internal static functions to genpd. Let's conform to the naming rules, by dropping the "pm_" prefix from these. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-09-23PM / Domains: Don't measure latency of ->power_on|off() during system PMUlf Hansson
Measure latency does by itself contribute to an increased latency, thus we should avoid it when it isn't needed. Currently genpd measures latencies in the system PM phase for the ->power_on|off() callbacks, except in the syscore case when it's not allowed to use ktime_get() as timekeeping may be suspended. Since there should be plenty of occasions during runtime PM to perform these measurements, let's rely on that and drop them from system PM. This will also make it consistent for how measurements are done of the runtime PM callbacks (as those may be invoked during system PM). Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-09-23PM / Domains: Remove redundant system PM callbacksUlf Hansson
In cases when the PM domain haven't assigned a system PM callback, the PM core fall-backs to check for the callback at the driver level instead. This makes it redundant to assign a pm_generic_* helper function to a corresponding system PM callback at a PM domain level. Therefore, let's remove these assignments in pm_genpd_init(). Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-09-23PM / Domains: Simplify detaching a device from its genpdUlf Hansson
There's no need to validate the PM domain by using genpd_lookup_dev() when removing the device via genpd's genpd_dev_pm_detach() function. That's because this function can't be called, unless there is a valid PM domain for the device. To simplify the behaviour, let's move code from pm_genpd_remove_device() into a new internal function, genpd_remove_device(), which is called from pm_genpd_remove_device() and genpd_dev_pm_detach(). Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Lina Iyer <lina.iyer@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-09-23Merge tag 'regmap-fix-v4.8-rc7' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap Pull regmap fix from Mark Brown: "A fix for an issue with double locking that was introduced earlier this release. I'd missed in review that we were already in a locked region when trying to drop part of the cache" * tag 'regmap-fix-v4.8-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap: regmap: fix deadlock on _regmap_raw_write() error path
2016-09-22regmap: fix deadlock on _regmap_raw_write() error pathNikita Yushchenko
Commit 815806e39bf6 ("regmap: drop cache if the bus transfer error") added a call to regcache_drop_region() to error path in _regmap_raw_write(). However that path runs with regmap lock taken, and regcache_drop_region() tries to re-take it, causing a deadlock. Fix that by calling map->cache_ops->drop() directly. Signed-off-by: Nikita Yushchenko <nikita.yoush@cogentembedded.com> Signed-off-by: Mark Brown <broonie@kernel.org>
2016-09-16PM / OPP: avoid maybe-uninitialized warningArnd Bergmann
When CONFIG_OPTIMIZE_INLINING is set and we are building with -Wmaybe-uninitialized enabled, we can get a warning for the opp core driver: drivers/base/power/opp/core.c: In function 'dev_pm_opp_set_rate': drivers/base/power/opp/core.c:560:8: warning: 'ou_volt_min' may be used uninitialized in this function [-Wmaybe-uninitialized] This has only now appeared as a result of commit 797da5598f3a ("PM / devfreq: Add COMPILE_TEST for build coverage"), which makes the driver visible in some configurations that didn't have it before. The warning is a false positive that I got with gcc-6.1.1, but there is a simple workaround in removing the local variables that we get warnings for (all three are affected depending on the configuration). This also makes the code easier to read. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Stephen Boyd <sboyd@codeaurora.org> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-09-16PM / Domains: Allow holes in genpd_data.domains arrayTomeu Vizoso
In platforms such as Rockchip's, the array of domains isn't always filled without holes, as which domains are present depend on the particular SoC revision. By allowing holes to be in the array, such SoCs can still use a single set of constants to index the array of power domains. Fixes: 0159ec670763 (PM / Domains: Verify the PM domain is present when adding a provider) Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com> Acked-by: Jon Hunter <jonathanh@nvidia.com> Acked-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Heiko Stuebner <heiko@sntech.de> Tested-by: Heiko Stuebner <heiko@sntech.de> Acked-by: Kevin Hilman <khilman@baylibre.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-09-16PM / runtime: Use _rcuidle for runtime suspend tracepointsPaul E. McKenney
Further testing with false negatives suppressed by commit 293e2421fe25 ("rcu: Remove superfluous versions of rcu_read_lock_sched_held()") identified a few more unprotected uses of RCU from the idle loop. Because RCU actively ignores idle-loop code (for energy-efficiency reasons, among other things), using RCU from the idle loop can result in too-short grace periods, in turn resulting in arbitrary misbehavior. The affected function is rpm_suspend(). The resulting lockdep-RCU splat is as follows: ------------------------------------------------------------------------ Warning from omap3 =============================== [ INFO: suspicious RCU usage. ] 4.6.0-rc5-next-20160426+ #1112 Not tainted ------------------------------- include/trace/events/rpm.h:63 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: [<c052ee24>] __pm_runtime_suspend+0x54/0x84 stack backtrace: CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.6.0-rc5-next-20160426+ #1112 Hardware name: Generic OMAP36xx (Flattened Device Tree) [<c0110308>] (unwind_backtrace) from [<c010c3a8>] (show_stack+0x10/0x14) [<c010c3a8>] (show_stack) from [<c047fec8>] (dump_stack+0xb0/0xe4) [<c047fec8>] (dump_stack) from [<c052d7b4>] (rpm_suspend+0x604/0x7e4) [<c052d7b4>] (rpm_suspend) from [<c052ee34>] (__pm_runtime_suspend+0x64/0x84) [<c052ee34>] (__pm_runtime_suspend) from [<c04bf3bc>] (omap2_gpio_prepare_for_idle+0x5c/0x70) [<c04bf3bc>] (omap2_gpio_prepare_for_idle) from [<c01255e8>] (omap_sram_idle+0x140/0x244) [<c01255e8>] (omap_sram_idle) from [<c0126b48>] (omap3_enter_idle_bm+0xfc/0x1ec) [<c0126b48>] (omap3_enter_idle_bm) from [<c0601db8>] (cpuidle_enter_state+0x80/0x3d4) [<c0601db8>] (cpuidle_enter_state) from [<c0183c74>] (cpu_startup_entry+0x198/0x3a0) [<c0183c74>] (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> [ rjw: Subject ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-09-13PM / Domains: Add support for removing nested PM domains by providerJon Hunter
If a device supports PM domains that are subdomains of another PM domain, then the PM domains should be removed in reverse order to ensure that the subdomains are removed first. Furthermore, if there is more than one provider, then there needs to be a way to remove the domains in reverse order for a specific provider. Add the function of_genpd_remove_last() to remove the last PM domain added by a given PM domain provider and return the generic_pm_domain structure for the PM domain that was removed. Signed-off-by: Jon Hunter <jonathanh@nvidia.com> Acked-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-09-13PM / Domains: Add support for removing PM domainsJon Hunter
The genpd framework allows users to add PM domains via the pm_genpd_init() function, however, there is no corresponding function to remove a PM domain. For most devices this may be fine as the PM domains are never removed, however, for devices that wish to populate the PM domains from within a driver, having the ability to remove a PM domain if the probing of the device fails or the driver is unloaded is necessary. Add the function pm_genpd_remove() to remove a PM domain by referencing it's generic_pm_domain structure. Note that the bulk of the code that removes the PM domain is placed in a separate local function genpd_remove() (which is called by pm_genpd_remove()). The code is structured in this way to prepare for adding another function to remove a PM domain by provider that will also call genpd_remove(). Note that users of genpd_remove() must call this function with the mutex, gpd_list_lock, held. PM domains can only be removed if the associated provider has been removed, they are not a parent domain to another PM domain and have no devices associated with them. Signed-off-by: Jon Hunter <jonathanh@nvidia.com> Acked-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-09-13PM / Domains: Store the provider in the PM domain structureJon Hunter
It is possible that a device has more than one provider of PM domains and to support the removal of a PM domain by provider, it is necessary to store a reference to the provider in the PM domain structure. Therefore, store a reference to the firmware node handle in the PM domain structure and populate it when providers (only device-tree based providers are currently supported by PM domains) are registered. Please note that when removing PM domains, it is necessary to verify that the PM domain provider has been removed from the list of providers before the PM domain can be removed. To do this add another member to the PM domain structure that indicates if the provider is present and set this member accordingly when providers are added and removed. Initialise the 'provider' and 'has_provider' members of the generic_pm_domain structure when a PM domains is added by calling pm_genpd_init(). Signed-off-by: Jon Hunter <jonathanh@nvidia.com> Acked-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-09-13PM / Domains: Prepare for adding support to remove PM domainsJon Hunter
In order to remove PM domains safely from the list of PM domains, it is necessary to adding locking for the PM domain list around any places where devices or subdomains are added to a PM domain. There are places where a reference to a PM domain is obtained via calling of_genpd_get_from_provider() before adding the device or the subdomain. In these cases a lock for the PM domain list needs to be held around the call to of_genpd_get_from_provider() and the call to add the device/subdomain. To avoid deadlocks by multiple attempts to obtain the PM domain list lock, add functions genpd_add_device() and genpd_add_subdomain() which require the user to hold the PM domain list lock when calling. Signed-off-by: Jon Hunter <jonathanh@nvidia.com> Acked-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-09-13PM / Domains: Verify the PM domain is present when adding a providerJon Hunter
When a PM domain provider is added, there is currently no way to tell if any PM domains associated with the provider are present. Naturally, the PM domain provider should not be registered if the PM domains have not been added. Nonetheless, verify that the PM domain(s) associated with a provider are present when registering the PM domain provider. This change adds a dependency on the function pm_genpd_present() when CONFIG_PM_GENERIC_DOMAINS_OF is enabled and so ensure this function is available when CONFIG_PM_GENERIC_DOMAINS_OF selected. Signed-off-by: Jon Hunter <jonathanh@nvidia.com> Acked-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-09-13PM / Domains: Don't expose xlate and provider helper functionsJon Hunter
Functions __of_genpd_xlate_simple(), __of_genpd_xlate_onecell() and __of_genpd_add_provider() are not used outside of the core generic PM domain code. Therefore, reduce the number of APIs exposed by making these static. At the same time don't expose the typedef for genpd_xlate_t either and make this a local definition as well. The functions are renamed to follow the naming conventions for static functions in the generic PM domain core. Signed-off-by: Jon Hunter <jonathanh@nvidia.com> Acked-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-09-13PM / Domains: Don't expose generic_pm_domain structure to clientsJon Hunter
There should be no need to expose the generic_pm_domain structure to clients and this eliminates the need to implement reference counting for any external reference to a PM domain. Therefore, make the functions pm_genpd_lookup_dev() and of_genpd_get_from_provider() private to the PM domain core. The functions are renamed in accordance with the naming conventions for genpd static functions. Signed-off-by: Jon Hunter <jonathanh@nvidia.com> Acked-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-09-13PM / Domains: Add new helper functions for device-treeJon Hunter
Ideally, if we are returning a reference to a PM domain via a call to of_genpd_get_from_provider(), then we should keep track of such references via a reference count. The reference count could then be used to determine if a PM domain can be safely removed. Alternatively, it is possible to avoid such external references by providing APIs to access the PM domain and hence, eliminate any calls to of_genpd_get_from_provider(). Add new helper functions for adding a device and a subdomain to a PM domain when using device-tree, so that external calls to of_genpd_get_from_provider() can be removed. Signed-off-by: Jon Hunter <jonathanh@nvidia.com> Acked-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-09-06Merge tag 'regmap-fix-v4.8-rc5' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap Pull regmap fixes from Mark Brown: "Several fixes here, the main one being the change from Lars-Peter which I'd been letting soak in -next since the merge window in case it uncovered further issues as it's a minimal fix rather than a change addressing the root cause of the problems (which would've been too invasive for -rc): - The biggest change is a fix from Lars-Peter to ensure that we don't create overlapping rbtree nodes which in turn avoids returning corrupt cache values to users, fixing some issues that were exposed by some recent optimisations with certain access patterns but had been present for a long time. - A fix from Elaine Zhang to stop us updating the cache if we get an I/O error when writing to the hardware. - A fix fromm Maarten ter Huurne to avoid uninitialized defaults in cases where we have non-readable registers but are initializing the cache by reading from the device" * tag 'regmap-fix-v4.8-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap: regmap: drop cache if the bus transfer error regmap: rbtree: Avoid overlapping nodes regmap: cache: Fix num_reg_defaults computation from reg_defaults_raw
2016-09-03Merge remote-tracking branch 'regmap/fix/rbtree' into regmap-linusMark Brown
2016-09-03Merge remote-tracking branch 'regmap/fix/cache' into regmap-linusMark Brown
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>
2016-08-30driver 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>
2016-08-06Merge 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>
2016-07-27Merge 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 ...
2016-07-27Merge 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