Commit Graph

999 Commits

Author SHA1 Message Date
Mike Rapoport
8a7f97b902 treewide: add checks for the return value of memblock_alloc*()
Add check for the return value of memblock_alloc*() functions and call
panic() in case of error.  The panic message repeats the one used by
panicing memblock allocators with adjustment of parameters to include
only relevant ones.

The replacement was mostly automated with semantic patches like the one
below with manual massaging of format strings.

  @@
  expression ptr, size, align;
  @@
  ptr = memblock_alloc(size, align);
  + if (!ptr)
  + 	panic("%s: Failed to allocate %lu bytes align=0x%lx\n", __func__, size, align);

[anders.roxell@linaro.org: use '%pa' with 'phys_addr_t' type]
  Link: http://lkml.kernel.org/r/20190131161046.21886-1-anders.roxell@linaro.org
[rppt@linux.ibm.com: fix format strings for panics after memblock_alloc]
  Link: http://lkml.kernel.org/r/1548950940-15145-1-git-send-email-rppt@linux.ibm.com
[rppt@linux.ibm.com: don't panic if the allocation in sparse_buffer_init fails]
  Link: http://lkml.kernel.org/r/20190131074018.GD28876@rapoport-lnx
[akpm@linux-foundation.org: fix xtensa printk warning]
Link: http://lkml.kernel.org/r/1548057848-15136-20-git-send-email-rppt@linux.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
Reviewed-by: Guo Ren <ren_guo@c-sky.com>		[c-sky]
Acked-by: Paul Burton <paul.burton@mips.com>		[MIPS]
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>	[s390]
Reviewed-by: Juergen Gross <jgross@suse.com>		[Xen]
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>	[m68k]
Acked-by: Max Filippov <jcmvbkbc@gmail.com>		[xtensa]
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christophe Leroy <christophe.leroy@c-s.fr>
Cc: Christoph Hellwig <hch@lst.de>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Dennis Zhou <dennis@kernel.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Guo Ren <guoren@kernel.org>
Cc: Mark Salter <msalter@redhat.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Rob Herring <robh@kernel.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-03-12 10:04:02 -07:00
Linus Torvalds
ef8006846a Merge tag 'pm-5.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management updates from Rafael Wysocki:
 "These are PM-runtime framework changes to use ktime instead of jiffies
  for accounting, new PM core flag to mark devices that don't need any
  form of power management, cpuidle updates including driver API
  documentation and a new governor, cpufreq updates including a new
  driver for Armada 8K, thermal cleanups and more, some energy-aware
  scheduling (EAS) enabling changes, new chips support in the intel_idle
  and RAPL drivers and assorted cleanups in some other places.

  Specifics:

   - Update the PM-runtime framework to use ktime instead of jiffies for
     accounting (Thara Gopinath, Vincent Guittot)

   - Optimize the autosuspend code in the PM-runtime framework somewhat
     (Ladislav Michl)

   - Add a PM core flag to mark devices that don't need any form of
     power management (Sudeep Holla)

   - Introduce driver API documentation for cpuidle and add a new
     cpuidle governor for tickless systems (Rafael Wysocki)

   - Add Jacobsville support to the intel_idle driver (Zhang Rui)

   - Clean up a cpuidle core header file and the cpuidle-dt and ACPI
     processor-idle drivers (Yangtao Li, Joseph Lo, Yazen Ghannam)

   - Add new cpufreq driver for Armada 8K (Gregory Clement)

   - Fix and clean up cpufreq core (Rafael Wysocki, Viresh Kumar, Amit
     Kucheria)

   - Add support for light-weight tear-down and bring-up of CPUs to the
     cpufreq core and use it in the cpufreq-dt driver (Viresh Kumar)

   - Fix cpu_cooling Kconfig dependencies, add support for CPU cooling
     auto-registration to the cpufreq core and use it in multiple
     cpufreq drivers (Amit Kucheria)

   - Fix some minor issues and do some cleanups in the davinci,
     e_powersaver, ap806, s5pv210, qcom and kryo cpufreq drivers
     (Bartosz Golaszewski, Gustavo Silva, Julia Lawall, Paweł Chmiel,
     Taniya Das, Viresh Kumar)

   - Add a Hisilicon CPPC quirk to the cppc_cpufreq driver (Xiongfeng
     Wang)

   - Clean up the intel_pstate and acpi-cpufreq drivers (Erwan Velu,
     Rafael Wysocki)

   - Clean up multiple cpufreq drivers (Yangtao Li)

   - Update cpufreq-related MAINTAINERS entries (Baruch Siach, Lukas
     Bulwahn)

   - Add support for exposing the Energy Model via debugfs and make
     multiple cpufreq drivers register an Energy Model to support
     energy-aware scheduling (Quentin Perret, Dietmar Eggemann, Matthias
     Kaehlcke)

   - Add Ice Lake mobile and Jacobsville support to the Intel RAPL
     power-capping driver (Gayatri Kammela, Zhang Rui)

   - Add a power estimation helper to the operating performance points
     (OPP) framework and clean up a core function in it (Quentin Perret,
     Viresh Kumar)

   - Make minor improvements in the generic power domains (genpd), OPP
     and system suspend frameworks and in the PM core (Aditya Pakki,
     Douglas Anderson, Greg Kroah-Hartman, Rafael Wysocki, Yangtao Li)"

* tag 'pm-5.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (80 commits)
  cpufreq: kryo: Release OPP tables on module removal
  cpufreq: ap806: add missing of_node_put after of_device_is_available
  cpufreq: acpi-cpufreq: Report if CPU doesn't support boost technologies
  cpufreq: Pass updated policy to driver ->setpolicy() callback
  cpufreq: Fix two debug messages in cpufreq_set_policy()
  cpufreq: Reorder and simplify cpufreq_update_policy()
  cpufreq: Add kerneldoc comments for two core functions
  PM / core: Add support to skip power management in device/driver model
  cpufreq: intel_pstate: Rework iowait boosting to be less aggressive
  cpufreq: intel_pstate: Eliminate intel_pstate_get_base_pstate()
  cpufreq: intel_pstate: Avoid redundant initialization of local vars
  powercap/intel_rapl: add Ice Lake mobile
  ACPI / processor: Set P_LVL{2,3} idle state descriptions
  cpufreq / cppc: Work around for Hisilicon CPPC cpufreq
  ACPI / CPPC: Add a helper to get desired performance
  cpufreq: davinci: move configuration to include/linux/platform_data
  cpufreq: speedstep: convert BUG() to BUG_ON()
  cpufreq: powernv: fix missing check of return value in init_powernv_pstates()
  cpufreq: longhaul: remove unneeded semicolon
  cpufreq: pcc-cpufreq: remove unneeded semicolon
  ..
2019-03-06 12:59:46 -08:00
David Hildenbrand
abd02ac616 PM/Hibernate: exclude all PageOffline() pages
The content of pages that are marked PG_offline is not of interest (e.g.
inflated by a balloon driver), let's skip these pages.

In saveable_highmem_page(), move the PageReserved() check to a new check
along with the PageOffline() check to separate it from the swsusp
checks.

[david@redhat.com: v2]
  Link: http://lkml.kernel.org/r/20181122100627.5189-9-david@redhat.com
Link: http://lkml.kernel.org/r/20181119101616.8901-9-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Len Brown <len.brown@intel.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Christian Hansen <chansen3@cisco.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Juergen Gross <jgross@suse.com>
Cc: Julien Freche <jfreche@vmware.com>
Cc: Kairui Song <kasong@redhat.com>
Cc: Kazuhito Hagio <k-hagio@ab.jp.nec.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Lianbo Jiang <lijiang@redhat.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Miles Chen <miles.chen@mediatek.com>
Cc: Nadav Amit <namit@vmware.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Omar Sandoval <osandov@fb.com>
Cc: Pankaj gupta <pagupta@redhat.com>
Cc: Pavel Tatashin <pasha.tatashin@oracle.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Xavier Deguillard <xdeguillard@vmware.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-03-05 21:07:14 -08:00
David Hildenbrand
5b56db3721 PM/Hibernate: use pfn_to_online_page()
Let's use pfn_to_online_page() instead of pfn_to_page() when checking
for saveable pages to not save/restore offline memory sections.

Link: http://lkml.kernel.org/r/20181119101616.8901-8-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Suggested-by: Michal Hocko <mhocko@kernel.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Len Brown <len.brown@intel.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Christian Hansen <chansen3@cisco.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Juergen Gross <jgross@suse.com>
Cc: Julien Freche <jfreche@vmware.com>
Cc: Kairui Song <kasong@redhat.com>
Cc: Kazuhito Hagio <k-hagio@ab.jp.nec.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Lianbo Jiang <lijiang@redhat.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Miles Chen <miles.chen@mediatek.com>
Cc: Nadav Amit <namit@vmware.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Omar Sandoval <osandov@fb.com>
Cc: Pankaj gupta <pagupta@redhat.com>
Cc: Pavel Tatashin <pasha.tatashin@oracle.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Xavier Deguillard <xdeguillard@vmware.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-03-05 21:07:14 -08:00
Rafael J. Wysocki
c3739c50ef Merge branches 'pm-core', 'pm-sleep', 'pm-qos', 'pm-domains' and 'pm-em'
* pm-core:
  PM / core: Add support to skip power management in device/driver model
  PM / suspend: Print debug messages for device using direct-complete
  PM-runtime: update time accounting only when enabled
  PM-runtime: Switch accounting over to ktime_get_mono_fast_ns()
  PM-runtime: Optimize pm_runtime_autosuspend_expiration()
  PM-runtime: Replace jiffies-based accounting with ktime-based accounting
  PM-runtime: update accounting_timestamp on enable
  PM: clock_ops: fix missing clk_prepare() return value check
  drm/i915: Move on the new pm runtime interface
  PM-runtime: Add new interface to get accounted time

* pm-sleep:
  PM / wakeup: fix kerneldoc comment for pm_wakeup_dev_event()

* pm-qos:
  PM: QoS: no need to check return value of debugfs_create functions

* pm-domains:
  PM / Domains: Mark "name" const in dev_pm_domain_attach_by_name()
  PM / Domains: Mark "name" const in genpd_dev_pm_attach_by_name()
  PM: domains: no need to check return value of debugfs_create functions

* pm-em:
  PM / EM: Expose the Energy Model in debugfs
2019-03-04 11:18:28 +01:00
Quentin Perret
9cac42d064 PM / EM: Expose the Energy Model in debugfs
The recently introduced Energy Model (EM) framework manages power cost
tables of CPUs. These tables are currently only visible from kernel
space. However, in order to debug the behaviour of subsystems that use
the EM (EAS for example), it is often required to know what the power
costs are from userspace.

For this reason, introduce under /sys/kernel/debug/energy_model a set of
directories representing the performance domains of the system. Each
performance domain contains a set of sub-directories representing the
different capacity states (cs) and their attributes, as well as a file
exposing the related CPUs.

The resulting hierarchy is as follows on Arm juno r0 for example:

    /sys/kernel/debug/energy_model
    ├── pd0
    │   ├── cpus
    │   ├── cs:450000
    │   │   ├── cost
    │   │   ├── frequency
    │   │   └── power
    │   ├── cs:575000
    │   │   ├── cost
    │   │   ├── frequency
    │   │   └── power
    │   ├── cs:700000
    │   │   ├── cost
    │   │   ├── frequency
    │   │   └── power
    │   ├── cs:775000
    │   │   ├── cost
    │   │   ├── frequency
    │   │   └── power
    │   └── cs:850000
    │       ├── cost
    │       ├── frequency
    │       └── power
    └── pd1
        ├── cpus
        ├── cs:1100000
        │   ├── cost
        │   ├── frequency
        │   └── power
        ├── cs:450000
        │   ├── cost
        │   ├── frequency
        │   └── power
        ├── cs:625000
        │   ├── cost
        │   ├── frequency
        │   └── power
        ├── cs:800000
        │   ├── cost
        │   ├── frequency
        │   └── power
        └── cs:950000
            ├── cost
            ├── frequency
            └── power

Signed-off-by: Quentin Perret <quentin.perret@arm.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-01-23 23:07:57 +01:00
Greg Kroah-Hartman
659dc4562c PM: QoS: no need to check return value of debugfs_create functions
When calling debugfs functions, there is no need to ever check the
return value.  The function can work or not, but the code logic should
never do something different based on this.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-01-22 23:12:12 +01:00
Arun KS
ca79b0c211 mm: convert totalram_pages and totalhigh_pages variables to atomic
totalram_pages and totalhigh_pages are made static inline function.

Main motivation was that managed_page_count_lock handling was complicating
things.  It was discussed in length here,
https://lore.kernel.org/patchwork/patch/995739/#1181785 So it seemes
better to remove the lock and convert variables to atomic, with preventing
poteintial store-to-read tearing as a bonus.

[akpm@linux-foundation.org: coding style fixes]
Link: http://lkml.kernel.org/r/1542090790-21750-4-git-send-email-arunks@codeaurora.org
Signed-off-by: Arun KS <arunks@codeaurora.org>
Suggested-by: Michal Hocko <mhocko@suse.com>
Suggested-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Reviewed-by: Pavel Tatashin <pasha.tatashin@soleen.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-12-28 12:11:47 -08:00
Linus Torvalds
17bf423a1f Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler updates from Ingo Molnar:
 "The main changes in this cycle were:

   - Introduce "Energy Aware Scheduling" - by Quentin Perret.

     This is a coherent topology description of CPUs in cooperation with
     the PM subsystem, with the goal to schedule more energy-efficiently
     on asymetric SMP platform - such as waking up tasks to the more
     energy-efficient CPUs first, as long as the system isn't
     oversubscribed.

     For details of the design, see:

        https://lore.kernel.org/lkml/20180724122521.22109-1-quentin.perret@arm.com/

   - Misc cleanups and smaller enhancements"

* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits)
  sched/fair: Select an energy-efficient CPU on task wake-up
  sched/fair: Introduce an energy estimation helper function
  sched/fair: Add over-utilization/tipping point indicator
  sched/fair: Clean-up update_sg_lb_stats parameters
  sched/toplogy: Introduce the 'sched_energy_present' static key
  sched/topology: Make Energy Aware Scheduling depend on schedutil
  sched/topology: Disable EAS on inappropriate platforms
  sched/topology: Add lowest CPU asymmetry sched_domain level pointer
  sched/topology: Reference the Energy Model of CPUs when available
  PM: Introduce an Energy Model management framework
  sched/cpufreq: Prepare schedutil for Energy Aware Scheduling
  sched/topology: Relocate arch_scale_cpu_capacity() to the internal header
  sched/core: Remove unnecessary unlikely() in push_*_task()
  sched/topology: Remove the ::smt_gain field from 'struct sched_domain'
  sched: Fix various typos in comments
  sched/core: Clean up the #ifdef block in add_nr_running()
  sched/fair: Make some variables static
  sched/core: Create task_has_idle_policy() helper
  sched/fair: Add lsub_positive() and use it consistently
  sched/fair: Mask UTIL_AVG_UNCHANGED usages
  ...
2018-12-26 14:56:10 -08:00
Rafael J. Wysocki
442a5d000a Merge branches 'pm-core', 'pm-qos', 'pm-domains' and 'pm-sleep'
* pm-core:
  PM-runtime: Switch autosuspend over to using hrtimers

* pm-qos:
  PM / QoS: Change to use DEFINE_SHOW_ATTRIBUTE macro

* pm-domains:
  PM / Domains: remove define_genpd_open_function() and define_genpd_debugfs_fops()

* pm-sleep:
  PM / sleep: convert to DEFINE_SHOW_ATTRIBUTE
2018-12-21 10:06:44 +01:00
Yangtao Li
943a10f852 PM / sleep: convert to DEFINE_SHOW_ATTRIBUTE
Use DEFINE_SHOW_ATTRIBUTE macro to simplify the code.

Signed-off-by: Yangtao Li <tiny.windzz@gmail.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-12-12 23:23:58 +01:00
Quentin Perret
27871f7a8a PM: Introduce an Energy Model management framework
Several subsystems in the kernel (task scheduler and/or thermal at the
time of writing) can benefit from knowing about the energy consumed by
CPUs. Yet, this information can come from different sources (DT or
firmware for example), in different formats, hence making it hard to
exploit without a standard API.

As an attempt to address this, introduce a centralized Energy Model
(EM) management framework which aggregates the power values provided
by drivers into a table for each performance domain in the system. The
power cost tables are made available to interested clients (e.g. task
scheduler or thermal) via platform-agnostic APIs. The overall design
is represented by the diagram below (focused on Arm-related drivers as
an example, but applicable to any architecture):

     +---------------+  +-----------------+  +-------------+
     | Thermal (IPA) |  | Scheduler (EAS) |  |    Other    |
     +---------------+  +-----------------+  +-------------+
             |                   | em_pd_energy()   |
             |                   | em_cpu_get()     |
             +-----------+       |         +--------+
                         |       |         |
                         v       v         v
                      +---------------------+
                      |                     |
                      |    Energy Model     |
                      |                     |
                      |     Framework       |
                      |                     |
                      +---------------------+
                         ^       ^       ^
                         |       |       | em_register_perf_domain()
              +----------+       |       +---------+
              |                  |                 |
      +---------------+  +---------------+  +--------------+
      |  cpufreq-dt   |  |   arm_scmi    |  |    Other     |
      +---------------+  +---------------+  +--------------+
              ^                  ^                 ^
              |                  |                 |
      +--------------+   +---------------+  +--------------+
      | Device Tree  |   |   Firmware    |  |      ?       |
      +--------------+   +---------------+  +--------------+

Drivers (typically, but not limited to, CPUFreq drivers) can register
data in the EM framework using the em_register_perf_domain() API. The
calling driver must provide a callback function with a standardized
signature that will be used by the EM framework to build the power
cost tables of the performance domain. This design should offer a lot of
flexibility to calling drivers which are free of reading information
from any location and to use any technique to compute power costs.
Moreover, the capacity states registered by drivers in the EM framework
are not required to match real performance states of the target. This
is particularly important on targets where the performance states are
not known by the OS.

The power cost coefficients managed by the EM framework are specified in
milli-watts. Although the two potential users of those coefficients (IPA
and EAS) only need relative correctness, IPA specifically needs to
compare the power of CPUs with the power of other components (GPUs, for
example), which are still expressed in absolute terms in their
respective subsystems. Hence, specifying the power of CPUs in
milli-watts should help transitioning IPA to using the EM framework
without introducing new problems by keeping units comparable across
sub-systems.
On the longer term, the EM of other devices than CPUs could also be
managed by the EM framework, which would enable to remove the absolute
unit. However, this is not absolutely required as a first step, so this
extension of the EM framework is left for later.

On the client side, the EM framework offers APIs to access the power
cost tables of a CPU (em_cpu_get()), and to estimate the energy
consumed by the CPUs of a performance domain (em_pd_energy()). Clients
such as the task scheduler can then use these APIs to access the shared
data structures holding the Energy Model of CPUs.

Signed-off-by: Quentin Perret <quentin.perret@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: adharmap@codeaurora.org
Cc: chris.redpath@arm.com
Cc: currojerez@riseup.net
Cc: dietmar.eggemann@arm.com
Cc: edubezval@gmail.com
Cc: gregkh@linuxfoundation.org
Cc: javi.merino@kernel.org
Cc: joel@joelfernandes.org
Cc: juri.lelli@redhat.com
Cc: morten.rasmussen@arm.com
Cc: patrick.bellasi@arm.com
Cc: pkondeti@codeaurora.org
Cc: skannan@codeaurora.org
Cc: smuckle@google.com
Cc: srinivas.pandruvada@linux.intel.com
Cc: thara.gopinath@linaro.org
Cc: tkjos@google.com
Cc: valentin.schneider@arm.com
Cc: vincent.guittot@linaro.org
Cc: viresh.kumar@linaro.org
Link: https://lkml.kernel.org/r/20181203095628.11858-4-quentin.perret@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-12-11 15:16:58 +01:00
Yangtao Li
96c6935212 PM / QoS: Change to use DEFINE_SHOW_ATTRIBUTE macro
Use DEFINE_SHOW_ATTRIBUTE macro to simplify the code.

Signed-off-by: Yangtao Li <tiny.windzz@gmail.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-11-29 22:28:11 +01:00
Mike Rapoport
7e1c4e2792 memblock: stop using implicit alignment to SMP_CACHE_BYTES
When a memblock allocation APIs are called with align = 0, the alignment
is implicitly set to SMP_CACHE_BYTES.

Implicit alignment is done deep in the memblock allocator and it can
come as a surprise.  Not that such an alignment would be wrong even
when used incorrectly but it is better to be explicit for the sake of
clarity and the prinicple of the least surprise.

Replace all such uses of memblock APIs with the 'align' parameter
explicitly set to SMP_CACHE_BYTES and stop implicit alignment assignment
in the memblock internal allocation functions.

For the case when memblock APIs are used via helper functions, e.g.  like
iommu_arena_new_node() in Alpha, the helper functions were detected with
Coccinelle's help and then manually examined and updated where
appropriate.

The direct memblock APIs users were updated using the semantic patch below:

@@
expression size, min_addr, max_addr, nid;
@@
(
|
- memblock_alloc_try_nid_raw(size, 0, min_addr, max_addr, nid)
+ memblock_alloc_try_nid_raw(size, SMP_CACHE_BYTES, min_addr, max_addr,
nid)
|
- memblock_alloc_try_nid_nopanic(size, 0, min_addr, max_addr, nid)
+ memblock_alloc_try_nid_nopanic(size, SMP_CACHE_BYTES, min_addr, max_addr,
nid)
|
- memblock_alloc_try_nid(size, 0, min_addr, max_addr, nid)
+ memblock_alloc_try_nid(size, SMP_CACHE_BYTES, min_addr, max_addr, nid)
|
- memblock_alloc(size, 0)
+ memblock_alloc(size, SMP_CACHE_BYTES)
|
- memblock_alloc_raw(size, 0)
+ memblock_alloc_raw(size, SMP_CACHE_BYTES)
|
- memblock_alloc_from(size, 0, min_addr)
+ memblock_alloc_from(size, SMP_CACHE_BYTES, min_addr)
|
- memblock_alloc_nopanic(size, 0)
+ memblock_alloc_nopanic(size, SMP_CACHE_BYTES)
|
- memblock_alloc_low(size, 0)
+ memblock_alloc_low(size, SMP_CACHE_BYTES)
|
- memblock_alloc_low_nopanic(size, 0)
+ memblock_alloc_low_nopanic(size, SMP_CACHE_BYTES)
|
- memblock_alloc_from_nopanic(size, 0, min_addr)
+ memblock_alloc_from_nopanic(size, SMP_CACHE_BYTES, min_addr)
|
- memblock_alloc_node(size, 0, nid)
+ memblock_alloc_node(size, SMP_CACHE_BYTES, nid)
)

[mhocko@suse.com: changelog update]
[akpm@linux-foundation.org: coding-style fixes]
[rppt@linux.ibm.com: fix missed uses of implicit alignment]
  Link: http://lkml.kernel.org/r/20181016133656.GA10925@rapoport-lnx
Link: http://lkml.kernel.org/r/1538687224-17535-1-git-send-email-rppt@linux.vnet.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Suggested-by: Michal Hocko <mhocko@suse.com>
Acked-by: Paul Burton <paul.burton@mips.com>	[MIPS]
Acked-by: Michael Ellerman <mpe@ellerman.id.au>	[powerpc]
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Richard Weinberger <richard@nod.at>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-10-31 08:54:16 -07:00
Mike Rapoport
57c8a661d9 mm: remove include/linux/bootmem.h
Move remaining definitions and declarations from include/linux/bootmem.h
into include/linux/memblock.h and remove the redundant header.

The includes were replaced with the semantic patch below and then
semi-automated removal of duplicated '#include <linux/memblock.h>

@@
@@
- #include <linux/bootmem.h>
+ #include <linux/memblock.h>

[sfr@canb.auug.org.au: dma-direct: fix up for the removal of linux/bootmem.h]
  Link: http://lkml.kernel.org/r/20181002185342.133d1680@canb.auug.org.au
[sfr@canb.auug.org.au: powerpc: fix up for removal of linux/bootmem.h]
  Link: http://lkml.kernel.org/r/20181005161406.73ef8727@canb.auug.org.au
[sfr@canb.auug.org.au: x86/kaslr, ACPI/NUMA: fix for linux/bootmem.h removal]
  Link: http://lkml.kernel.org/r/20181008190341.5e396491@canb.auug.org.au
Link: http://lkml.kernel.org/r/1536927045-23536-30-git-send-email-rppt@linux.vnet.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Ley Foon Tan <lftan@altera.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Paul Burton <paul.burton@mips.com>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Serge Semin <fancer.lancer@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-10-31 08:54:16 -07:00
Mike Rapoport
eb31d559f1 memblock: remove _virt from APIs returning virtual address
The conversion is done using

sed -i 's@memblock_virt_alloc@memblock_alloc@g' \
	$(git grep -l memblock_virt_alloc)

Link: http://lkml.kernel.org/r/1536927045-23536-8-git-send-email-rppt@linux.vnet.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Ley Foon Tan <lftan@altera.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Paul Burton <paul.burton@mips.com>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Serge Semin <fancer.lancer@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-10-31 08:54:15 -07:00
Rafael J. Wysocki
3f858ae02c Merge branches 'acpi-pm' and 'pm-sleep'
* acpi-pm:
  ACPI / PM: LPIT: Register sysfs attributes based on FADT

* pm-sleep:
  x86-32, hibernate: Adjust in_suspend after resumed on 32bit system
  x86-32, hibernate: Set up temporary text mapping for 32bit system
  x86-32, hibernate: Switch to relocated restore code during resume on 32bit system
  x86-32, hibernate: Switch to original page table after resumed
  x86-32, hibernate: Use the page size macro instead of constant value
  x86-32, hibernate: Use temp_pgt as the temporary page table
  x86, hibernate: Rename temp_level4_pgt to temp_pgt
  x86-32, hibernate: Enable CONFIG_ARCH_HIBERNATION_HEADER on 32bit system
  x86, hibernate: Extract the common code of 64/32 bit system
  x86-32/asm/power: Create stack frames in hibernate_asm_32.S
  PM / hibernate: Check the success of generating md5 digest before hibernation
  x86, hibernate: Fix nosave_regions setup for hibernation
  PM / sleep: Show freezing tasks that caused a suspend abort
  PM / hibernate: Documentation: fix image_size default value
2018-10-18 12:27:30 +02:00
Greg Kroah-Hartman
eb81bfb224 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
Dmitry writes:
  "Input updates for v4.19-rc7

   - we added a few scheduling points into various input interfaces to
     ensure that large writes will not cause RCU stalls
   - fixed configuring PS/2 keyboards as wakeup devices on newer
     platforms
   - added a new Xbox gamepad ID."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
  Input: uinput - add a schedule point in uinput_inject_events()
  Input: evdev - add a schedule point in evdev_write()
  Input: mousedev - add a schedule point in mousedev_write()
  Input: i8042 - enable keyboard wakeups by default when s2idle is used
  Input: xpad - add support for Xbox1 PDP Camo series gamepad
2018-10-12 12:35:02 +02:00
Daniel Drake
684bec1092 Input: i8042 - enable keyboard wakeups by default when s2idle is used
Previously, on typical consumer laptops, pressing a key on the keyboard
when the system is in suspend would cause it to wake up (default or
unconditional behaviour). This happens because the EC generates a SCI
interrupt in this scenario.

That is no longer true on modern laptops based on Intel WhiskeyLake,
including Acer Swift SF314-55G, Asus UX333FA, Asus UX433FN and Asus
UX533FD. We confirmed with Asus EC engineers that the "Modern Standby"
design has been modified so that the EC no longer generates a SCI
in this case; the keyboard controller itself should be used for wakeup.

In order to retain the standard behaviour of being able to use the
keyboard to wake up the system, enable serio wakeups by default on
platforms that are using s2idle.

Link: https://lkml.kernel.org/r/CAB4CAwfQ0mPMqCLp95TVjw4J0r5zKPWkSvvkK4cpZUGE--w8bQ@mail.gmail.com
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Daniel Drake <drake@endlessm.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2018-10-01 15:58:53 -07:00
Todd Brandt
8412dbd642 PM / sleep: Show freezing tasks that caused a suspend abort
For debug purposes it would be nice to see which tasks
caused a suspend abort, i.e. which tasks were still
in the process of freezing when a wakeup event occurred.
This patch adds the info to pm_debug_messages.

Signed-off-by: Todd Brandt <todd.e.brandt@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-09-10 12:09:10 +02:00
zhangyi (F)
3df6f61fff PM / sleep: wakeup: Fix build error caused by missing SRCU support
Commit ea0212f40c (power: auto select CONFIG_SRCU) made the code in
drivers/base/power/wakeup.c use SRCU instead of RCU, but it forgot to
select CONFIG_SRCU in Kconfig, which leads to the following build
error if CONFIG_SRCU is not selected somewhere else:

drivers/built-in.o: In function `wakeup_source_remove':
(.text+0x3c6fc): undefined reference to `synchronize_srcu'
drivers/built-in.o: In function `pm_print_active_wakeup_sources':
(.text+0x3c7a8): undefined reference to `__srcu_read_lock'
drivers/built-in.o: In function `pm_print_active_wakeup_sources':
(.text+0x3c84c): undefined reference to `__srcu_read_unlock'
drivers/built-in.o: In function `device_wakeup_arm_wake_irqs':
(.text+0x3d1d8): undefined reference to `__srcu_read_lock'
drivers/built-in.o: In function `device_wakeup_arm_wake_irqs':
(.text+0x3d228): undefined reference to `__srcu_read_unlock'
drivers/built-in.o: In function `device_wakeup_disarm_wake_irqs':
(.text+0x3d24c): undefined reference to `__srcu_read_lock'
drivers/built-in.o: In function `device_wakeup_disarm_wake_irqs':
(.text+0x3d29c): undefined reference to `__srcu_read_unlock'
drivers/built-in.o:(.data+0x4158): undefined reference to `process_srcu'

Fix this error by selecting CONFIG_SRCU when PM_SLEEP is enabled.

Fixes: ea0212f40c (power: auto select CONFIG_SRCU)
Cc: 4.2+ <stable@vger.kernel.org> # 4.2+
Signed-off-by: zhangyi (F) <yi.zhang@huawei.com>
[ rjw: Minor subject/changelog fixups ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-08-15 00:07:08 +02:00
Linus Torvalds
b018fc9800 Merge tag 'pm-4.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management updates from Rafael Wysocki:
 "These add a new framework for CPU idle time injection, to be used by
  all of the idle injection code in the kernel in the future, fix some
  issues and add a number of relatively small extensions in multiple
  places.

  Specifics:

   - Add a new framework for CPU idle time injection (Daniel Lezcano).

   - Add AVS support to the armada-37xx cpufreq driver (Gregory
     CLEMENT).

   - Add support for current CPU frequency reporting to the ACPI CPPC
     cpufreq driver (George Cherian).

   - Rework the cooling device registration in the imx6q/thermal driver
     (Bastian Stender).

   - Make the pcc-cpufreq driver refuse to work with dynamic scaling
     governors on systems with many CPUs to avoid scalability issues
     with it (Rafael Wysocki).

   - Fix the intel_pstate driver to report different maximum CPU
     frequencies on systems where they really are different and to
     ignore the turbo active ratio if hardware-managend P-states (HWP)
     are in use; make it use the match_string() helper (Xie Yisheng,
     Srinivas Pandruvada).

   - Fix a minor deferred probe issue in the qcom-kryo cpufreq driver
     (Niklas Cassel).

   - Add a tracepoint for the tracking of frequency limits changes (from
     Andriod) to the cpufreq core (Ruchi Kandoi).

   - Fix a circular lock dependency between CPU hotplug and sysfs
     locking in the cpufreq core reported by lockdep (Waiman Long).

   - Avoid excessive error reports on driver registration failures in
     the ARM cpuidle driver (Sudeep Holla).

   - Add a new device links flag to the driver core to make links go
     away automatically on supplier driver removal (Vivek Gautam).

   - Eliminate potential race condition between system-wide power
     management transitions and system shutdown (Pingfan Liu).

   - Add a quirk to save NVS memory on system suspend for the ASUS 1025C
     laptop (Willy Tarreau).

   - Make more systems use suspend-to-idle (instead of ACPI S3) by
     default (Tristian Celestin).

   - Get rid of stack VLA usage in the low-level hibernation code on
     64-bit x86 (Kees Cook).

   - Fix error handling in the hibernation core and mark an expected
     fall-through switch in it (Chengguang Xu, Gustavo Silva).

   - Extend the generic power domains (genpd) framework to support
     attaching a device to a power domain by name (Ulf Hansson).

   - Fix device reference counting and user limits initialization in the
     devfreq core (Arvind Yadav, Matthias Kaehlcke).

   - Fix a few issues in the rk3399_dmc devfreq driver and improve its
     documentation (Enric Balletbo i Serra, Lin Huang, Nick Milner).

   - Drop a redundant error message from the exynos-ppmu devfreq driver
     (Markus Elfring)"

* tag 'pm-4.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (35 commits)
  PM / reboot: Eliminate race between reboot and suspend
  PM / hibernate: Mark expected switch fall-through
  cpufreq: intel_pstate: Ignore turbo active ratio in HWP
  cpufreq: Fix a circular lock dependency problem
  cpu/hotplug: Add a cpus_read_trylock() function
  x86/power/hibernate_64: Remove VLA usage
  cpufreq: trace frequency limits change
  cpufreq: intel_pstate: Show different max frequency with turbo 3 and HWP
  cpufreq: pcc-cpufreq: Disable dynamic scaling on many-CPU systems
  cpufreq: qcom-kryo: Silently error out on EPROBE_DEFER
  cpufreq / CPPC: Add cpuinfo_cur_freq support for CPPC
  cpufreq: armada-37xx: Add AVS support
  dt-bindings: marvell: Add documentation for the Armada 3700 AVS binding
  PM / devfreq: rk3399_dmc: Fix duplicated opp table on reload.
  PM / devfreq: Init user limits from OPP limits, not viceversa
  PM / devfreq: rk3399_dmc: fix spelling mistakes.
  PM / devfreq: rk3399_dmc: do not print error when get supply and clk defer.
  dt-bindings: devfreq: rk3399_dmc: move interrupts to be optional.
  PM / devfreq: rk3399_dmc: remove wait for dcf irq event.
  dt-bindings: clock: add rk3399 DDR3 standard speed bins.
  ...
2018-08-14 13:12:24 -07:00
Pingfan Liu
55f2503c3b PM / reboot: Eliminate race between reboot and suspend
At present, "systemctl suspend" and "shutdown" can run in parrallel. A
system can suspend after devices_shutdown(), and resume. Then the shutdown
task goes on to power off. This causes many devices are not really shut
off. Hence replacing reboot_mutex with system_transition_mutex (renamed
from pm_mutex) to achieve the exclusion. The renaming of pm_mutex as
system_transition_mutex can be better to reflect the purpose of the mutex.

Signed-off-by: Pingfan Liu <kernelfans@gmail.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-08-06 12:35:20 +02:00
Gustavo A. R. Silva
82837ad5bd PM / hibernate: Mark expected switch fall-through
In preparation to enabling -Wimplicit-fallthrough, mark switch cases
where we are expecting to fall through.

This addresses Coverity-ID: 114713 ("Missing break in switch").

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-08-06 10:32:32 +02:00
Chengguang Xu
d5641c64c4 PM / hibernate: cast PAGE_SIZE to int when comparing with error code
If PAGE_SIZE is unsigned type then negative error code will be
larger than PAGE_SIZE.

Signed-off-by: Chengguang Xu <cgxu519@gmx.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-07-02 11:48:30 +02:00