Commit Graph

248 Commits

Author SHA1 Message Date
Rafael J. Wysocki dfad78e07e Merge branches 'pm-sleep', 'pm-domains' and 'pm-docs'
Merge changes related to system sleep, PM domains changes and power
management documentation changes for 5.18-rc1:

 - Fix load_image_and_restore() error path (Ye Bin).

 - Fix typos in comments in the system wakeup hadling code (Tom Rix).

 - Clean up non-kernel-doc comments in hibernation code (Jiapeng
   Chong).

 - Fix __setup handler error handling in system-wide suspend and
   hibernation core code (Randy Dunlap).

 - Add device name to suspend_report_result() (Youngjin Jang).

 - Make virtual guests honour ACPI S4 hardware signature by
   default (David Woodhouse).

 - Block power off of a parent PM domain unless child is in deepest
   state (Ulf Hansson).

 - Use dev_err_probe() to simplify error handling for generic PM
   domains (Ahmad Fatoum).

 - Fix sleep-in-atomic bug caused by genpd_debug_remove() (Shawn Guo).

 - Document Intel uncore frequency scaling (Srinivas Pandruvada).

* pm-sleep:
  PM: hibernate: Honour ACPI hardware signature by default for virtual guests
  PM: sleep: Add device name to suspend_report_result()
  PM: suspend: fix return value of __setup handler
  PM: hibernate: fix __setup handler error handling
  PM: hibernate: Clean up non-kernel-doc comments
  PM: sleep: wakeup: Fix typos in comments
  PM: hibernate: fix load_image_and_restore() error path

* pm-domains:
  PM: domains: Fix sleep-in-atomic bug caused by genpd_debug_remove()
  PM: domains: use dev_err_probe() to simplify error handling
  PM: domains: Prevent power off for parent unless child is in deepest state

* pm-docs:
  Documentation: admin-guide: pm: Document uncore frequency scaling
2022-03-18 18:29:21 +01:00
Dmitry Baryshkov 524bb1da78 PM: core: keep irq flags in device_pm_check_callbacks()
The function device_pm_check_callbacks() can be called under the spin
lock (in the reported case it happens from genpd_add_device() ->
dev_pm_domain_set(), when the genpd uses spinlocks rather than mutexes.

However this function uncoditionally uses spin_lock_irq() /
spin_unlock_irq(), thus not preserving the CPU flags. Use the
irqsave/irqrestore instead.

The backtrace for the reference:
[    2.752010] ------------[ cut here ]------------
[    2.756769] raw_local_irq_restore() called with IRQs enabled
[    2.762596] WARNING: CPU: 4 PID: 1 at kernel/locking/irqflag-debug.c:10 warn_bogus_irq_restore+0x34/0x50
[    2.772338] Modules linked in:
[    2.775487] CPU: 4 PID: 1 Comm: swapper/0 Tainted: G S                5.17.0-rc6-00384-ge330d0d82eff-dirty #684
[    2.781384] Freeing initrd memory: 46024K
[    2.785839] pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[    2.785841] pc : warn_bogus_irq_restore+0x34/0x50
[    2.785844] lr : warn_bogus_irq_restore+0x34/0x50
[    2.785846] sp : ffff80000805b7d0
[    2.785847] x29: ffff80000805b7d0 x28: 0000000000000000 x27: 0000000000000002
[    2.785850] x26: ffffd40e80930b18 x25: ffff7ee2329192b8 x24: ffff7edfc9f60800
[    2.785853] x23: ffffd40e80930b18 x22: ffffd40e80930d30 x21: ffff7edfc0dffa00
[    2.785856] x20: ffff7edfc09e3768 x19: 0000000000000000 x18: ffffffffffffffff
[    2.845775] x17: 6572206f74206465 x16: 6c696166203a3030 x15: ffff80008805b4f7
[    2.853108] x14: 0000000000000000 x13: ffffd40e809550b0 x12: 00000000000003d8
[    2.860441] x11: 0000000000000148 x10: ffffd40e809550b0 x9 : ffffd40e809550b0
[    2.867774] x8 : 00000000ffffefff x7 : ffffd40e809ad0b0 x6 : ffffd40e809ad0b0
[    2.875107] x5 : 000000000000bff4 x4 : 0000000000000000 x3 : 0000000000000000
[    2.882440] x2 : 0000000000000000 x1 : 0000000000000000 x0 : ffff7edfc03a8000
[    2.889774] Call trace:
[    2.892290]  warn_bogus_irq_restore+0x34/0x50
[    2.896770]  _raw_spin_unlock_irqrestore+0x94/0xa0
[    2.901690]  genpd_unlock_spin+0x20/0x30
[    2.905724]  genpd_add_device+0x100/0x2d0
[    2.909850]  __genpd_dev_pm_attach+0xa8/0x23c
[    2.914329]  genpd_dev_pm_attach_by_id+0xc4/0x190
[    2.919167]  genpd_dev_pm_attach_by_name+0x3c/0xd0
[    2.924086]  dev_pm_domain_attach_by_name+0x24/0x30
[    2.929102]  psci_dt_attach_cpu+0x24/0x90
[    2.933230]  psci_cpuidle_probe+0x2d4/0x46c
[    2.937534]  platform_probe+0x68/0xe0
[    2.941304]  really_probe.part.0+0x9c/0x2fc
[    2.945605]  __driver_probe_device+0x98/0x144
[    2.950085]  driver_probe_device+0x44/0x15c
[    2.954385]  __device_attach_driver+0xb8/0x120
[    2.958950]  bus_for_each_drv+0x78/0xd0
[    2.962896]  __device_attach+0xd8/0x180
[    2.966843]  device_initial_probe+0x14/0x20
[    2.971144]  bus_probe_device+0x9c/0xa4
[    2.975092]  device_add+0x380/0x88c
[    2.978679]  platform_device_add+0x114/0x234
[    2.983067]  platform_device_register_full+0x100/0x190
[    2.988344]  psci_idle_init+0x6c/0xb0
[    2.992113]  do_one_initcall+0x74/0x3a0
[    2.996060]  kernel_init_freeable+0x2fc/0x384
[    3.000543]  kernel_init+0x28/0x130
[    3.004132]  ret_from_fork+0x10/0x20
[    3.007817] irq event stamp: 319826
[    3.011404] hardirqs last  enabled at (319825): [<ffffd40e7eda0268>] __up_console_sem+0x78/0x84
[    3.020332] hardirqs last disabled at (319826): [<ffffd40e7fd6d9d8>] el1_dbg+0x24/0x8c
[    3.028458] softirqs last  enabled at (318312): [<ffffd40e7ec90410>] _stext+0x410/0x588
[    3.036678] softirqs last disabled at (318299): [<ffffd40e7ed1bf68>] __irq_exit_rcu+0x158/0x174
[    3.045607] ---[ end trace 0000000000000000 ]---

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-03-10 19:40:15 +01:00
Youngjin Jang a759de6991 PM: sleep: Add device name to suspend_report_result()
Currently, suspend_report_result() prints only function information.

If any driver uses a common PM function, nobody knows who exactly
called the failing function.

A device pinter is needed to recognize the failing device.

For example:

 PM: dpm_run_callback(): pnp_bus_suspend+0x0/0x10 returns 0
 PM: dpm_run_callback(): pci_pm_suspend+0x0/0x150 returns 0

become after the change:

 serial 00:05: PM: dpm_run_callback(): pnp_bus_suspend+0x0/0x10 returns 0
 pci 0000:00:01.3: PM: dpm_run_callback(): pci_pm_suspend+0x0/0x150 returns 0

Signed-off-by: Youngjin Jang <yj84.jang@samsung.com>
[ rjw: Changelog edits ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-03-08 19:57:01 +01:00
Rafael J. Wysocki 544e737dea PM: sleep: Fix error handling in dpm_prepare()
Commit 2aa36604e8 ("PM: sleep: Avoid calling put_device() under
dpm_list_mtx") forgot to update the while () loop termination
condition to also break the loop if error is nonzero, which
causes the loop to become infinite if device_prepare() returns
an error for one device.

Add the missing !error check.

Fixes: 2aa36604e8 ("PM: sleep: Avoid calling put_device() under dpm_list_mtx")
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reported-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Cc: All applicable <stable@vger.kernel.org>
2021-12-17 18:36:08 +01:00
Rafael J. Wysocki 2aa36604e8 PM: sleep: Avoid calling put_device() under dpm_list_mtx
It is generally unsafe to call put_device() with dpm_list_mtx held,
because the given device's release routine may carry out an action
depending on that lock which then may deadlock, so modify the
system-wide suspend and resume of devices to always drop dpm_list_mtx
before calling put_device() (and adjust white space somewhat while
at it).

For instance, this prevents the following splat from showing up in
the kernel log after a system resume in certain configurations:

[ 3290.969514] ======================================================
[ 3290.969517] WARNING: possible circular locking dependency detected
[ 3290.969519] 5.15.0+ #2420 Tainted: G S
[ 3290.969523] ------------------------------------------------------
[ 3290.969525] systemd-sleep/4553 is trying to acquire lock:
[ 3290.969529] ffff888117ab1138 ((wq_completion)hci0#2){+.+.}-{0:0}, at: flush_workqueue+0x87/0x4a0
[ 3290.969554]
               but task is already holding lock:
[ 3290.969556] ffffffff8280fca8 (dpm_list_mtx){+.+.}-{3:3}, at: dpm_resume+0x12e/0x3e0
[ 3290.969571]
               which lock already depends on the new lock.

[ 3290.969573]
               the existing dependency chain (in reverse order) is:
[ 3290.969575]
               -> #3 (dpm_list_mtx){+.+.}-{3:3}:
[ 3290.969583]        __mutex_lock+0x9d/0xa30
[ 3290.969591]        device_pm_add+0x2e/0xe0
[ 3290.969597]        device_add+0x4d5/0x8f0
[ 3290.969605]        hci_conn_add_sysfs+0x43/0xb0 [bluetooth]
[ 3290.969689]        hci_conn_complete_evt.isra.71+0x124/0x750 [bluetooth]
[ 3290.969747]        hci_event_packet+0xd6c/0x28a0 [bluetooth]
[ 3290.969798]        hci_rx_work+0x213/0x640 [bluetooth]
[ 3290.969842]        process_one_work+0x2aa/0x650
[ 3290.969851]        worker_thread+0x39/0x400
[ 3290.969859]        kthread+0x142/0x170
[ 3290.969865]        ret_from_fork+0x22/0x30
[ 3290.969872]
               -> #2 (&hdev->lock){+.+.}-{3:3}:
[ 3290.969881]        __mutex_lock+0x9d/0xa30
[ 3290.969887]        hci_event_packet+0xba/0x28a0 [bluetooth]
[ 3290.969935]        hci_rx_work+0x213/0x640 [bluetooth]
[ 3290.969978]        process_one_work+0x2aa/0x650
[ 3290.969985]        worker_thread+0x39/0x400
[ 3290.969993]        kthread+0x142/0x170
[ 3290.969999]        ret_from_fork+0x22/0x30
[ 3290.970004]
               -> #1 ((work_completion)(&hdev->rx_work)){+.+.}-{0:0}:
[ 3290.970013]        process_one_work+0x27d/0x650
[ 3290.970020]        worker_thread+0x39/0x400
[ 3290.970028]        kthread+0x142/0x170
[ 3290.970033]        ret_from_fork+0x22/0x30
[ 3290.970038]
               -> #0 ((wq_completion)hci0#2){+.+.}-{0:0}:
[ 3290.970047]        __lock_acquire+0x15cb/0x1b50
[ 3290.970054]        lock_acquire+0x26c/0x300
[ 3290.970059]        flush_workqueue+0xae/0x4a0
[ 3290.970066]        drain_workqueue+0xa1/0x130
[ 3290.970073]        destroy_workqueue+0x34/0x1f0
[ 3290.970081]        hci_release_dev+0x49/0x180 [bluetooth]
[ 3290.970130]        bt_host_release+0x1d/0x30 [bluetooth]
[ 3290.970195]        device_release+0x33/0x90
[ 3290.970201]        kobject_release+0x63/0x160
[ 3290.970211]        dpm_resume+0x164/0x3e0
[ 3290.970215]        dpm_resume_end+0xd/0x20
[ 3290.970220]        suspend_devices_and_enter+0x1a4/0xba0
[ 3290.970229]        pm_suspend+0x26b/0x310
[ 3290.970236]        state_store+0x42/0x90
[ 3290.970243]        kernfs_fop_write_iter+0x135/0x1b0
[ 3290.970251]        new_sync_write+0x125/0x1c0
[ 3290.970257]        vfs_write+0x360/0x3c0
[ 3290.970263]        ksys_write+0xa7/0xe0
[ 3290.970269]        do_syscall_64+0x3a/0x80
[ 3290.970276]        entry_SYSCALL_64_after_hwframe+0x44/0xae
[ 3290.970284]
               other info that might help us debug this:

[ 3290.970285] Chain exists of:
                 (wq_completion)hci0#2 --> &hdev->lock --> dpm_list_mtx

[ 3290.970297]  Possible unsafe locking scenario:

[ 3290.970299]        CPU0                    CPU1
[ 3290.970300]        ----                    ----
[ 3290.970302]   lock(dpm_list_mtx);
[ 3290.970306]                                lock(&hdev->lock);
[ 3290.970310]                                lock(dpm_list_mtx);
[ 3290.970314]   lock((wq_completion)hci0#2);
[ 3290.970319]
                *** DEADLOCK ***

[ 3290.970321] 7 locks held by systemd-sleep/4553:
[ 3290.970325]  #0: ffff888103bcd448 (sb_writers#4){.+.+}-{0:0}, at: ksys_write+0xa7/0xe0
[ 3290.970341]  #1: ffff888115a14488 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x103/0x1b0
[ 3290.970355]  #2: ffff888100f719e0 (kn->active#233){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x10c/0x1b0
[ 3290.970369]  #3: ffffffff82661048 (autosleep_lock){+.+.}-{3:3}, at: state_store+0x12/0x90
[ 3290.970384]  #4: ffffffff82658ac8 (system_transition_mutex){+.+.}-{3:3}, at: pm_suspend+0x9f/0x310
[ 3290.970399]  #5: ffffffff827f2a48 (acpi_scan_lock){+.+.}-{3:3}, at: acpi_suspend_begin+0x4c/0x80
[ 3290.970416]  #6: ffffffff8280fca8 (dpm_list_mtx){+.+.}-{3:3}, at: dpm_resume+0x12e/0x3e0
[ 3290.970428]
               stack backtrace:
[ 3290.970431] CPU: 3 PID: 4553 Comm: systemd-sleep Tainted: G S                5.15.0+ #2420
[ 3290.970438] Hardware name: Dell Inc. XPS 13 9380/0RYJWW, BIOS 1.5.0 06/03/2019
[ 3290.970441] Call Trace:
[ 3290.970446]  dump_stack_lvl+0x44/0x57
[ 3290.970454]  check_noncircular+0x105/0x120
[ 3290.970468]  ? __lock_acquire+0x15cb/0x1b50
[ 3290.970474]  __lock_acquire+0x15cb/0x1b50
[ 3290.970487]  lock_acquire+0x26c/0x300
[ 3290.970493]  ? flush_workqueue+0x87/0x4a0
[ 3290.970503]  ? __raw_spin_lock_init+0x3b/0x60
[ 3290.970510]  ? lockdep_init_map_type+0x58/0x240
[ 3290.970519]  flush_workqueue+0xae/0x4a0
[ 3290.970526]  ? flush_workqueue+0x87/0x4a0
[ 3290.970544]  ? drain_workqueue+0xa1/0x130
[ 3290.970552]  drain_workqueue+0xa1/0x130
[ 3290.970561]  destroy_workqueue+0x34/0x1f0
[ 3290.970572]  hci_release_dev+0x49/0x180 [bluetooth]
[ 3290.970624]  bt_host_release+0x1d/0x30 [bluetooth]
[ 3290.970687]  device_release+0x33/0x90
[ 3290.970695]  kobject_release+0x63/0x160
[ 3290.970705]  dpm_resume+0x164/0x3e0
[ 3290.970710]  ? dpm_resume_early+0x251/0x3b0
[ 3290.970718]  dpm_resume_end+0xd/0x20
[ 3290.970723]  suspend_devices_and_enter+0x1a4/0xba0
[ 3290.970737]  pm_suspend+0x26b/0x310
[ 3290.970746]  state_store+0x42/0x90
[ 3290.970755]  kernfs_fop_write_iter+0x135/0x1b0
[ 3290.970764]  new_sync_write+0x125/0x1c0
[ 3290.970777]  vfs_write+0x360/0x3c0
[ 3290.970785]  ksys_write+0xa7/0xe0
[ 3290.970794]  do_syscall_64+0x3a/0x80
[ 3290.970803]  entry_SYSCALL_64_after_hwframe+0x44/0xae
[ 3290.970811] RIP: 0033:0x7f41b1328164
[ 3290.970819] Code: 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f 1f 80 00 00 00 00 8b 05 4a d2 2c 00 48 63 ff 85 c0 75 13 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 54 f3 c3 66 90 55 53 48 89 d5 48 89 f3 48 83
[ 3290.970824] RSP: 002b:00007ffe6ae21b28 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
[ 3290.970831] RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00007f41b1328164
[ 3290.970836] RDX: 0000000000000004 RSI: 000055965e651070 RDI: 0000000000000004
[ 3290.970839] RBP: 000055965e651070 R08: 000055965e64f390 R09: 00007f41b1e3d1c0
[ 3290.970843] R10: 000000000000000a R11: 0000000000000246 R12: 0000000000000004
[ 3290.970846] R13: 0000000000000001 R14: 000055965e64f2b0 R15: 0000000000000004

Cc: All applicable <stable@vger.kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-11-05 16:10:11 +01:00
Ulf Hansson a2bd7be12b PM: sleep: Fix runtime PM based cpuidle support
In the cpuidle-psci case, runtime PM in combination with the generic PM
domain (genpd), may be used when entering/exiting a shared idlestate. More
precisely, genpd relies on runtime PM to be enabled for the attached device
(in this case it belongs to a CPU), to properly manage the reference
counting of its PM domain.

This works fine most of the time, but during system suspend in
dpm_suspend_late(), the PM core disables runtime PM for all devices. Beyond
this point, calls to pm_runtime_get_sync() to runtime resume a device may
fail and therefore it could also mess up the reference counting in genpd.

To fix this problem, let's call wake_up_all_idle_cpus() in
dpm_suspend_late(), prior to disabling runtime PM. In this way a device
that belongs to a CPU, becomes runtime resumed through cpuidle-psci and
stays like that, because the runtime PM usage count has been bumped in
device_prepare().

Diagnosed-by: Maulik Shah <mkshah@codeaurora.org>
Suggested-by: Rafael J. Wysocki <rafael@kernel.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-11-04 19:45:38 +01:00
Rafael J. Wysocki 23f62d7ab2 PM: sleep: Pause cpuidle later and resume it earlier during system transitions
Commit 8651f97bd9 ("PM / cpuidle: System resume hang fix with
cpuidle") that introduced cpuidle pausing during system suspend
did that to work around a platform firmware issue causing systems
to hang during resume if CPUs were allowed to enter idle states
in the system suspend and resume code paths.

However, pausing cpuidle before the last phase of suspending
devices is the source of an otherwise arbitrary difference between
the suspend-to-idle path and other system suspend variants, so it is
cleaner to do that later, before taking secondary CPUs offline (it
is still safer to take secondary CPUs offline with cpuidle paused,
though).

Modify the code accordingly, but in order to avoid code duplication,
introduce new wrapper functions, pm_sleep_disable_secondary_cpus()
and pm_sleep_enable_secondary_cpus(), to combine cpuidle_pause()
and cpuidle_resume(), respectively, with the handling of secondary
CPUs during system-wide transitions to sleep states.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Tested-by: Ulf Hansson <ulf.hansson@linaro.org>
2021-10-26 15:52:07 +02:00
Rafael J. Wysocki 8d89835b04 PM: suspend: Do not pause cpuidle in the suspend-to-idle path
It is pointless to pause cpuidle in the suspend-to-idle path,
because it is going to be resumed in the same path later and
pausing it does not serve any particular purpose in that case.

Rework the code to avoid doing that.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Tested-by: Ulf Hansson <ulf.hansson@linaro.org>
2021-10-26 15:52:07 +02:00
Rafael J. Wysocki 928265e360 PM: sleep: Do not let "syscore" devices runtime-suspend during system transitions
There is no reason to allow "syscore" devices to runtime-suspend
during system-wide PM transitions, because they are subject to the
same possible failure modes as any other devices in that respect.

Accordingly, change device_prepare() and device_complete() to call
pm_runtime_get_noresume() and pm_runtime_put(), respectively, for
"syscore" devices too.

Fixes: 057d51a126 ("Merge branch 'pm-sleep'")
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: 3.10+ <stable@vger.kernel.org> # 3.10+
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
2021-10-22 18:09:58 +02:00
Prasad Sodagudi 4a9344cd0a PM: sleep: core: Avoid setting power.must_resume to false
There are variables(power.may_skip_resume and dev->power.must_resume)
and DPM_FLAG_MAY_SKIP_RESUME flags to control the resume of devices after
a system wide suspend transition.

Setting the DPM_FLAG_MAY_SKIP_RESUME flag means that the driver allows
its "noirq" and "early" resume callbacks to be skipped if the device
can be left in suspend after a system-wide transition into the working
state. PM core determines that the driver's "noirq" and "early" resume
callbacks should be skipped or not with dev_pm_skip_resume() function by
checking power.may_skip_resume variable.

power.must_resume variable is getting set to false in __device_suspend()
function without checking device's DPM_FLAG_MAY_SKIP_RESUME settings.
In problematic scenario, where all the devices in the suspend_late
stage are successful and some device can fail to suspend in
suspend_noirq phase. So some devices successfully suspended in suspend_late
stage are not getting chance to execute __device_suspend_noirq()
to set dev->power.must_resume variable to true and not getting
resumed in early_resume phase.

Add a check for device's DPM_FLAG_MAY_SKIP_RESUME flag before
setting power.must_resume variable in __device_suspend function.

Fixes: 6e176bf8d4 ("PM: sleep: core: Do not skip callbacks in the resume phase")
Signed-off-by: Prasad Sodagudi <psodagud@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-09-07 21:18:34 +02:00
Mark-PK Tsai 75674eb06a PM: sleep: Use ktime_us_delta() in initcall_debug_report()
Use ktime_us_delta() to make the debug log more precise instead of
shifting the return value of ktime_to_ns() applied to a ktime_sub()
result by 10 bit positions to the right.

Signed-off-by: Mark-PK Tsai <mark-pk.tsai@mediatek.com>
[ rjw: Changelog rewrite, subject edits ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-07-01 18:44:02 +02:00
Bjorn Helgaas eb23d91af5 PM: sleep: Use dev_printk() when possible
Use dev_printk() when possible to make messages more consistent with other
device-related messages.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-01-27 19:21:17 +01:00
Patrice Chotard 4e1d9a737d PM: sleep: Add dev_wakeup_path() helper
Add dev_wakeup_path() helper to avoid to spread
dev->power.wakeup_path test in drivers.

Signed-off-by: Patrice Chotard <patrice.chotard@st.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-11-23 18:34:55 +01:00
Chen Yu f39ee99f51 PM: sleep: Print driver flags for all devices during suspend/resume
Currently there are 4 driver flags to control system suspend/resume
behavior: DPM_FLAG_NO_DIRECT_COMPLETE, DPM_FLAG_SMART_PREPARE,
DPM_FLAG_SMART_SUSPEND and DPM_FLAG_MAY_SKIP_RESUME.

Print these flags during suspend/resume so as to get a brief
understanding of the expected behavior of each device, and to
facilitate suspend/resume debugging/tuning.

To enable this tracing:
echo 'file drivers/base/power/main.c +p' >
/sys/kernel/debug/dynamic_debug/control

Signed-off-by: Chen Yu <yu.c.chen@intel.com>
[ rjw: Subject and changelog edits ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-11-10 19:41:40 +01:00
Tom Rix d298787dbb PM: sleep: remove unreachable break
A break following a return statement is pointless, so drop it.

Signed-off-by: Tom Rix <trix@redhat.com>
[ rjw: Subject and changelog edits ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-10-22 18:43:31 +02:00
Rafael J. Wysocki e3eb6e8fba PM: sleep: core: Fix the handling of pending runtime resume requests
It has been reported that system-wide suspend may be aborted in the
absence of any wakeup events due to unforseen interactions of it with
the runtume PM framework.

One failing scenario is when there are multiple devices sharing an
ACPI power resource and runtime-resume needs to be carried out for
one of them during system-wide suspend (for example, because it needs
to be reconfigured before the whole system goes to sleep).  In that
case, the runtime-resume of that device involves turning the ACPI
power resource "on" which in turn causes runtime-resume requests
to be queued up for all of the other devices sharing it.  Those
requests go to the runtime PM workqueue which is frozen during
system-wide suspend, so they are not actually taken care of until
the resume of the whole system, but the pm_runtime_barrier()
call in __device_suspend() sees them and triggers system wakeup
events for them which then cause the system-wide suspend to be
aborted if wakeup source objects are in active use.

Of course, the logic that leads to triggering those wakeup events is
questionable in the first place, because clearly there are cases in
which a pending runtime resume request for a device is not connected
to any real wakeup events in any way (like the one above).  Moreover,
it is racy, because the device may be resuming already by the time
the pm_runtime_barrier() runs and so if the driver doesn't take care
of signaling the wakeup event as appropriate, it will be lost.
However, if the driver does take care of that, the extra
pm_wakeup_event() call in the core is redundant.

Accordingly, drop the conditional pm_wakeup_event() call fron
__device_suspend() and make the latter call pm_runtime_barrier()
alone.  Also modify the comment next to that call to reflect the new
code and extend it to mention the need to avoid unwanted interactions
between runtime PM and system-wide device suspend callbacks.

Fixes: 1e2ef05bb8 ("PM: Limit race conditions between runtime PM and system sleep (v2)")
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Reported-by: Utkarsh H Patel <utkarsh.h.patel@intel.com>
Tested-by: Utkarsh H Patel <utkarsh.h.patel@intel.com>
Tested-by: Pengfei Xu <pengfei.xu@intel.com>
Cc: All applicable <stable@vger.kernel.org>
2020-08-25 16:28:23 +02:00
Dmitry Safonov 9cb8f069de kernel: rename show_stack_loglvl() => show_stack()
Now the last users of show_stack() got converted to use an explicit log
level, show_stack_loglvl() can drop it's redundant suffix and become once
again well known show_stack().

Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20200418201944.482088-51-dima@arista.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09 09:39:13 -07:00
Dmitry Safonov 3f0543780e power: use show_stack_loglvl()
Aligning with other watchdog messages just before panic - use KERN_EMERG.

Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Len Brown <len.brown@intel.com>
Cc: Pavel Machek <pavel@ucw.cz>
Link: http://lkml.kernel.org/r/20200418201944.482088-47-dima@arista.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09 09:39:12 -07:00
Rafael J. Wysocki edb7f9d6b5 Merge back system-wide PM updates for v5.8. 2020-04-24 21:37:01 +02:00
Rafael J. Wysocki 2a3f34750b PM: sleep: core: Rename DPM_FLAG_LEAVE_SUSPENDED
Rename DPM_FLAG_LEAVE_SUSPENDED to DPM_FLAG_MAY_SKIP_RESUME which
matches its purpose more closely.

No functional impact.

Suggested-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Wolfram Sang <wsa@the-dreams.de> # for I2C
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
2020-04-24 21:34:22 +02:00
Rafael J. Wysocki e07515563d PM: sleep: core: Rename DPM_FLAG_NEVER_SKIP
Rename DPM_FLAG_NEVER_SKIP to DPM_FLAG_NO_DIRECT_COMPLETE which
matches its purpose more closely.

No functional impact.

Suggested-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com> # for PCI parts
Acked-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
2020-04-24 21:33:09 +02:00
Rafael J. Wysocki fa2bfead91 PM: sleep: core: Rename dev_pm_smart_suspend_and_suspended()
Because all callers of dev_pm_smart_suspend_and_suspended use it only
for checking whether or not to skip driver suspend callbacks for a
device, rename it to dev_pm_skip_suspend() in analogy with
dev_pm_skip_resume().

No functional impact.

Suggested-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
2020-04-24 21:32:41 +02:00
Rafael J. Wysocki 76c70cb58c PM: sleep: core: Rename dev_pm_may_skip_resume()
The name of dev_pm_may_skip_resume() may be easily confused with the
power.may_skip_resume flag which is not checked by that function, so
rename the former as dev_pm_skip_resume().

No functional impact.

Suggested-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
2020-04-24 21:32:11 +02:00
Rafael J. Wysocki 0fe8a1be59 PM: sleep: core: Rework the power.may_skip_resume handling
Because the power.may_skip_resume device status bit is taken
into account in combination with the DPM_FLAG_LEAVE_SUSPENDED
driver flag, it can be set to 'true' for all devices in the
"suspend" phase of a suspend-resume cycle, so do that.

Then, neither the PM core nor the middle-layer (sybsystem) code
handling it needs to set it to 'true' any more and it just has
to be cleared if there is a reason to avoid skipping the "noirq"
and "early" resume callbacks provided by the driver, so update
the code in question accordingly.

Suggested-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
2020-04-24 21:31:28 +02:00
Rafael J. Wysocki 6e176bf8d4 PM: sleep: core: Do not skip callbacks in the resume phase
The current code in device_resume_noirq() causes the entire early
resume and resume phases of device suspend to be skipped for
devices for which the noirq resume phase have been skipped (due
to the LEAVE_SUSPENDED flag being set) on the premise that those
devices should stay in runtime-suspend after system-wide resume.

However, that may not be correct in two situations.  First, the
middle layer (subsystem) noirq resume callback may be missing for
a given device, but its early resume callback may be present and it
may need to do something even if it decides to skip the driver
callback.  Second, if the device's wakeup settings were adjusted
in the suspend phase without resuming the device (that was in
runtime suspend at that time), they most likely need to be
adjusted again in the resume phase and so the driver callback
in that phase needs to be run.

For the above reason, modify the core to allow the middle layer
->resume_late callback to run even if its ->resume_noirq callback
is missing (and the core has skipped the driver-level callback
in that phase) and to allow all device callbacks to run in the
resume phase.  Also make the core set the PM-runtime status of
devices with SMART_SUSPEND set whose resume callbacks are not
skipped to "active" in the "noirq" resume phase and update the
affected subsystems (PCI and ACPI) accordingly.

After this change, middle-layer (subsystem) callbacks will always
be invoked in all phases of system suspend and resume and driver
callbacks will always run in the prepare, suspend, resume, and
complete phases for all devices.

For devices with SMART_SUSPEND set, driver callbacks will be
skipped in the late and noirq phases of system suspend if those
devices remain in runtime suspend in __device_suspend_late().
Driver callbacks will also be skipped for them during the
noirq and early phases of the "thaw" transition related to
hibernation in that case.

Setting LEAVE_SUSPENDED means that the driver allows its callbacks
to be skipped in the noirq and early phases of system resume, but
some additional conditions need to be met for that to happen (among
other things, the power.may_skip_resume flag needs to be set for the
device during system suspend for the driver callbacks to be skipped
during the subsequent resume transition).

For all devices with SMART_SUSPEND set whose driver callbacks are
invoked during system resume, the PM-runtime status will be set to
"active" (by the core).

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
2020-04-24 21:31:14 +02:00
Kai-Heng Feng 09beebd8f9 PM: sleep: core: Switch back to async_schedule_dev()
Commit 8b9ec6b732 ("PM core: Use new async_schedule_dev command")
introduced a new function for better performance.

However commit f2a424f6c6 ("PM / core: Introduce dpm_async_fn()
helper") went back to the non-optimized version, async_schedule().

So switch back to the sync_schedule_dev() to improve performance

Fixes: f2a424f6c6 ("PM / core: Introduce dpm_async_fn() helper")
Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-04-22 16:36:18 +02:00
Rafael J. Wysocki 30205377dd PM: sleep: core: Fold functions into their callers
Fold four functions in the PM core that each have only one caller
now into their callers.

No intentional functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
2020-04-20 10:32:16 +02:00
Rafael J. Wysocki 107d47b2b9 PM: sleep: core: Simplify the SMART_SUSPEND flag handling
The code to handle the SMART_SUSPEND driver PM flag is hard to follow
and somewhat inconsistent with respect to devices without middle-layer
(subsystem) callbacks.

Namely, for those devices the core takes the role of a middle layer
in providing the expected ordering of execution of callbacks (under
the assumption that the drivers setting SMART_SUSPEND can reuse their
PM-runtime callbacks directly for system-wide suspend).  To that end,
it prevents driver ->suspend_late and ->suspend_noirq callbacks from
being executed for devices that are still runtime-suspended in
__device_suspend_late(), because running the same callback funtion
that was previously run by PM-runtime for them may be invalid.

However, it does that only for devices without any middle-layer
callbacks for the late/noirq/early suspend/resume phases even
though it would be simpler and more consistent to skip the
driver-lavel callbacks for all devices with SMART_SUSPEND set
that are runtime-suspended in __device_suspend_late().

Simplify the code in accordance with the above observation.

Suggested-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
2020-04-20 10:32:15 +02:00
Rafael J. Wysocki b5252a6cbb PM: sleep: core: Drop racy and redundant checks from device_prepare()
Alan Stern points out that the WARN_ON() check in device_prepare()
is racy (because the PM-runtime API can be disabled briefly for any
device at any time and system suspend can start at any time too) and
the pm_runtime_suspended() check in the computation of the
direct_complete flag value is redundant (because it will be
repeated later anyway).

Drop both these checks accordingly.

Reported-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-04-01 11:38:49 +02:00
Madhuparna Bhowmik 42beb82ec4 PM: sleep: core: Use built-in RCU list checking
This patch passes the cond argument to list_for_each_entry_rcu()
to fix the following false-positive lockdep warnings:
(with CONFIG_PROVE_RCU_LIST = y)

[  330.302784] =============================
[  330.302789] WARNING: suspicious RCU usage
[  330.302796] 5.6.0-rc1+ #5 Not tainted
[  330.302801] -----------------------------
[  330.302808] drivers/base/power/main.c:326 RCU-list traversed in non-reader section!!

[  330.303303] =============================
[  330.303307] WARNING: suspicious RCU usage
[  330.303311] 5.6.0-rc1+ #5 Not tainted
[  330.303315] -----------------------------
[  330.303319] drivers/base/power/main.c:1698 RCU-list traversed in non-reader section!!

[  331.934969] =============================
[  331.934971] WARNING: suspicious RCU usage
[  331.934973] 5.6.0-rc1+ #5 Not tainted
[  331.934975] -----------------------------
[  331.934977] drivers/base/power/main.c:1238 RCU-list traversed in non-reader section!!

[  332.467772] WARNING: suspicious RCU usage
[  332.467775] 5.6.0-rc1+ #5 Not tainted
[  332.467775] -----------------------------
[  332.467778] drivers/base/power/main.c:269 RCU-list traversed in non-reader section!!

Signed-off-by: Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-03-04 11:05:59 +01:00
Rafael J. Wysocki 0552e05fdf PM: core: Fix handling of devices deleted during system-wide resume
If a device is deleted by one of its system-wide resume callbacks
(for example, because it does not appear to be present or accessible
any more) along with its children, the resume of the children may
continue leading to use-after-free errors and other issues
(potentially).

Namely, if the device's children are resumed asynchronously, their
resume may have been scheduled already before the device's callback
runs and so the device may be deleted while dpm_wait_for_superior()
is being executed for them.  The memory taken up by the parent device
object may be freed then while dpm_wait() is waiting for the parent's
resume callback to complete, which leads to a use-after-free.
Moreover, the resume of the children is really not expected to
continue after they have been unregistered, so it must be terminated
right away in that case.

To address this problem, modify dpm_wait_for_superior() to check
if the target device is still there in the system-wide PM list of
devices and if so, to increment its parent's reference counter, both
under dpm_list_mtx which prevents device_del() running for the child
from dropping the parent's reference counter prematurely.

If the device is not present in the system-wide PM list of devices
any more, the resume of it cannot continue, so check that again after
dpm_wait() returns, which means that the parent's callback has been
completed, and pass the result of that check to the caller of
dpm_wait_for_superior() to allow it to abort the device's resume
if it is not there any more.

Link: https://lore.kernel.org/linux-pm/1579568452-27253-1-git-send-email-chanho.min@lge.com
Reported-by: Chanho Min <chanho.min@lge.com>
Cc: All applicable <stable@vger.kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-24 14:27:05 +01:00
Rafael J. Wysocki b605c44c30 PM: sleep: Drop dpm_noirq_begin() and dpm_noirq_end()
Note that after previous changes dpm_noirq_begin() and
dpm_noirq_end() each have only one caller, so move the code from
them to their respective callers and drop them.

Also note that dpm_noirq_resume_devices() and
dpm_noirq_suspend_devices() need not be exported any more, so make
them both static.

This change is not expected to alter functionality.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
2019-07-23 09:46:56 +02:00
Rafael J. Wysocki 56b9918490 PM: sleep: Simplify suspend-to-idle control flow
After commit 33e4f80ee6 ("ACPI / PM: Ignore spurious SCI wakeups
from suspend-to-idle") the "noirq" phases of device suspend and
resume may run for multiple times during suspend-to-idle, if there
are spurious system wakeup events while suspended.  However, this
is complicated and fragile and actually unnecessary.

The main reason for doing this is that on some systems the EC may
signal system wakeup events (power button events, for example) as
well as events that should not cause the system to resume (spurious
system wakeup events).  Thus, in order to determine whether or not
a given event signaled by the EC while suspended is a proper system
wakeup one, the EC GPE needs to be dispatched and to start with that
was achieved by allowing the ACPI SCI action handler to run, which
was only possible after calling resume_device_irqs().

However, dispatching the EC GPE this way turned out to take too much
time in some cases and some EC events might be missed due to that, so
commit 68e2201185 ("ACPI: EC: Dispatch the EC GPE directly on
s2idle wake") started to dispatch the EC GPE right after a wakeup
event has been detected, so in fact the full ACPI SCI action handler
doesn't need to run any more to deal with the wakeups coming from the
EC.

Use this observation to simplify the suspend-to-idle control flow
so that the "noirq" phases of device suspend and resume are each
run only once in every suspend-to-idle cycle, which is reported to
significantly reduce power drawn by some systems when suspended to
idle (by allowing them to reach a deep platform-wide low-power state
through the suspend-to-idle flow).  [What appears to happen is that
the "noirq" resume of devices after a spurious EC wakeup brings some
devices into a state in which they prevent the platform from reaching
the deep low-power state going forward, even after a subsequent
"noirq" suspend phase, and on some systems the EC triggers such
wakeups already when the "noirq" suspend of devices is running for
the first time in the given suspend/resume cycle, so the platform
cannot reach the deep low-power state at all.]

First, make acpi_s2idle_wake() use the acpi_ec_dispatch_gpe() return
value to determine whether or not the wakeup may have been triggered
by the EC (in which case the system wakeup is canceled and ACPI
events are processed in order to determine whether or not the event
is a proper system wakeup one) and use rearm_wake_irq() (introduced
by a previous change) in it to rearm the ACPI SCI for system wakeup
detection in case the system will remain suspended.

Second, drop acpi_s2idle_sync(), which is not needed any more, and
the corresponding global platform suspend-to-idle callback.

Next, drop the pm_wakeup_pending() check (which is an optimization
only) from __device_suspend_noirq() to prevent it from returning
errors on system wakeups occurring before the "noirq" phase of
device suspend is complete (as in the case of suspend-to-idle it is
not known whether or not these wakeups are suprious at that point),
in order to avoid having to carry out a "noirq" resume of devices
on a spurious system wakeup.

Finally, change the code flow in s2idle_loop() to (1) run the
"noirq" suspend of devices once before starting the loop, (2) check
for spurious EC wakeups (via the platform ->wake callback) for the
first time before calling s2idle_enter(), and (3) run the "noirq"
resume of devices once after leaving the loop.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
2019-07-23 09:46:40 +02:00
Rafael J. Wysocki 02bd45a28b PM: sleep: Drop dev_pm_skip_next_resume_phases()
After recent hibernation-related changes, there are no more callers
of dev_pm_skip_next_resume_phases() except for the PM core itself
in which it is more straightforward to run the statements from
that function directly, so do that and drop it.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2019-07-04 10:50:40 +02:00
Bart Van Assche 3540d38dd3 PM: sleep: Show how long dpm_suspend_start() and dpm_suspend_end() take
When debugging device driver power management code it is convenient to
know how much time is spent in the "suspend start" and "suspend end"
phases. Hence log the time spent in these phases.

Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-06-14 11:06:35 +02:00
Linus Torvalds cf482a49af Driver core/kobject patches for 5.2-rc1
Here is the "big" set of driver core patches for 5.2-rc1
 
 There are a number of ACPI patches in here as well, as Rafael said they
 should go through this tree due to the driver core changes they
 required.  They have all been acked by the ACPI developers.
 
 There are also a number of small subsystem-specific changes in here, due
 to some changes to the kobject core code.  Those too have all been acked
 by the various subsystem maintainers.
 
 As for content, it's pretty boring outside of the ACPI changes:
   - spdx cleanups
   - kobject documentation updates
   - default attribute groups for kobjects
   - other minor kobject/driver core fixes
 
 All have been in linux-next for a while with no reported issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-5.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core/kobject updates from Greg KH:
 "Here is the "big" set of driver core patches for 5.2-rc1

  There are a number of ACPI patches in here as well, as Rafael said
  they should go through this tree due to the driver core changes they
  required. They have all been acked by the ACPI developers.

  There are also a number of small subsystem-specific changes in here,
  due to some changes to the kobject core code. Those too have all been
  acked by the various subsystem maintainers.

  As for content, it's pretty boring outside of the ACPI changes:
   - spdx cleanups
   - kobject documentation updates
   - default attribute groups for kobjects
   - other minor kobject/driver core fixes

  All have been in linux-next for a while with no reported issues"

* tag 'driver-core-5.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (47 commits)
  kobject: clean up the kobject add documentation a bit more
  kobject: Fix kernel-doc comment first line
  kobject: Remove docstring reference to kset
  firmware_loader: Fix a typo ("syfs" -> "sysfs")
  kobject: fix dereference before null check on kobj
  Revert "driver core: platform: Fix the usage of platform device name(pdev->name)"
  init/config: Do not select BUILD_BIN2C for IKCONFIG
  Provide in-kernel headers to make extending kernel easier
  kobject: Improve doc clarity kobject_init_and_add()
  kobject: Improve docs for kobject_add/del
  driver core: platform: Fix the usage of platform device name(pdev->name)
  livepatch: Replace klp_ktype_patch's default_attrs with groups
  cpufreq: schedutil: Replace default_attrs field with groups
  padata: Replace padata_attr_type default_attrs field with groups
  irqdesc: Replace irq_kobj_type's default_attrs field with groups
  net-sysfs: Replace ktype default_attrs field with groups
  block: Replace all ktype default_attrs with groups
  samples/kobject: Replace foo_ktype's default_attrs field with groups
  kobject: Add support for default attribute groups to kobj_type
  driver core: Postpone DMA tear-down until after devres release for probe failure
  ...
2019-05-07 13:01:40 -07:00
Linus Torvalds 0968621917 Printk changes for 5.2
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Merge tag 'printk-for-5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk

Pull printk updates from Petr Mladek:

 - Allow state reset of printk_once() calls.

 - Prevent crashes when dereferencing invalid pointers in vsprintf().
   Only the first byte is checked for simplicity.

 - Make vsprintf warnings consistent and inlined.

 - Treewide conversion of obsolete %pf, %pF to %ps, %pF printf
   modifiers.

 - Some clean up of vsprintf and test_printf code.

* tag 'printk-for-5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk:
  lib/vsprintf: Make function pointer_string static
  vsprintf: Limit the length of inlined error messages
  vsprintf: Avoid confusion between invalid address and value
  vsprintf: Prevent crash when dereferencing invalid pointers
  vsprintf: Consolidate handling of unknown pointer specifiers
  vsprintf: Factor out %pO handler as kobject_string()
  vsprintf: Factor out %pV handler as va_format()
  vsprintf: Factor out %p[iI] handler as ip_addr_string()
  vsprintf: Do not check address of well-known strings
  vsprintf: Consistent %pK handling for kptr_restrict == 0
  vsprintf: Shuffle restricted_pointer()
  printk: Tie printk_once / printk_deferred_once into .data.once for reset
  treewide: Switch printk users from %pf and %pF to %ps and %pS, respectively
  lib/test_printf: Switch to bitmap_zalloc()
2019-05-07 09:18:12 -07:00
Ulf Hansson dc351d4c5f PM / core: Propagate dev->power.wakeup_path when no callbacks
The dev->power.direct_complete flag may become set in device_prepare() in
case the device don't have any PM callbacks (dev->power.no_pm_callbacks is
set). This leads to a broken behaviour, when there is child having wakeup
enabled and relies on its parent to be used in the wakeup path.

More precisely, when the direct complete path becomes selected for the
child in __device_suspend(), the propagation of the dev->power.wakeup_path
becomes skipped as well.

Let's address this problem, by checking if the device is a part the wakeup
path or has wakeup enabled, then prevent the direct complete path from
being used.

Reported-by: Loic Pallardy <loic.pallardy@st.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
[ rjw: Comment cleanup ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-04-12 11:03:53 +02:00
Yangtao Li f2a424f6c6 PM / core: Introduce dpm_async_fn() helper
When we want to execute device pm functions asynchronously, we'll
do the following for the device:

  1) reinit_completion(&dev->power.completion);
  2) Check if the device enables asynchronous suspend.
  3) If necessary, execute the corresponding function asynchronously.

There are a lot of such repeated operations here, in fact we can avoid
this. So introduce dpm_async_fn() to have better code readability and
reuse.

And use this function to do some cleanup.

Signed-off-by: Yangtao Li <tiny.windzz@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-04-10 10:03:22 +02:00
Sakari Ailus d75f773c86 treewide: Switch printk users from %pf and %pF to %ps and %pS, respectively
%pF and %pf are functionally equivalent to %pS and %ps conversion
specifiers. The former are deprecated, therefore switch the current users
to use the preferred variant.

The changes have been produced by the following command:

	git grep -l '%p[fF]' | grep -v '^\(tools\|Documentation\)/' | \
	while read i; do perl -i -pe 's/%pf/%ps/g; s/%pF/%pS/g;' $i; done

And verifying the result.

Link: http://lkml.kernel.org/r/20190325193229.23390-1-sakari.ailus@linux.intel.com
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: sparclinux@vger.kernel.org
Cc: linux-um@lists.infradead.org
Cc: xen-devel@lists.xenproject.org
Cc: linux-acpi@vger.kernel.org
Cc: linux-pm@vger.kernel.org
Cc: drbd-dev@lists.linbit.com
Cc: linux-block@vger.kernel.org
Cc: linux-mmc@vger.kernel.org
Cc: linux-nvdimm@lists.01.org
Cc: linux-pci@vger.kernel.org
Cc: linux-scsi@vger.kernel.org
Cc: linux-btrfs@vger.kernel.org
Cc: linux-f2fs-devel@lists.sourceforge.net
Cc: linux-mm@kvack.org
Cc: ceph-devel@vger.kernel.org
Cc: netdev@vger.kernel.org
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Acked-by: David Sterba <dsterba@suse.com> (for btrfs)
Acked-by: Mike Rapoport <rppt@linux.ibm.com> (for mm/memblock.c)
Acked-by: Bjorn Helgaas <bhelgaas@google.com> (for drivers/pci)
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
2019-04-09 14:19:06 +02:00
Yangtao Li 0b237cb2fc PM / core: fix kerneldoc comment for device_pm_wait_for_dev()
Rearrange comment to make the comment style consistent, the previous
function parameters are described first.

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>
2019-04-09 12:18:01 +02:00
Yangtao Li c4a586fdd4 PM / core: fix kerneldoc comment for dpm_watchdog_handler()
This brings the kernel doc in line with the function signature.

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>
2019-04-09 12:18:00 +02:00
Greg Kroah-Hartman 5de363b66a drivers: base: power: add proper SPDX identifiers on files that did not have them.
There were a few files in the driver core power code that did not have
SPDX identifiers on them, so fix that up.  At the same time, remove the
"free form" text that specified the license of the file, as that is
impossible for any tool to properly parse.

Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-04 20:03:40 +02:00
Linus Torvalds 9352ca585b Additional power management updates for 5.1-rc1
- Fix registration of new cpuidle governors partially broken during
    the 5.0 development cycle by mistake (Rafael Wysocki).
 
  - Avoid integer overflows in the menu cpuidle governor by making
    it discard the overflowing data points upfront (Rafael Wysocki).
 
  - Fix minor mistake in the recent update of the iowait boost
    computation in the intel_pstate driver (Rafael Wysocki).
 
  - Drop incorrect __init annotation from one function in the pxa2xx
    cpufreq driver (Arnd Bergmann).
 
  - Fix the operating performance points (OPP) framework
    initialization for devices in multiple power domains if
    only one of them is scalable (Rajendra Nayak).
 
  - Fix mistake in dev_pm_opp_set_rate() which causes it to skip
    updating the performance state if the new frequency is the same
    as the old one (Viresh Kumar).
 
  - Rework the cancellation of wakeup source timers to avoid
    potential issues with it and do some cleanups unlocked by
    that change (Viresh Kumar, Rafael Wysocki).
 
  - Clean up the code computing the active/suspended time of devices
    in the PM-runtime framework after recent changes (Ulf Hansson).
 
  - Make the power management infrastructure code use pr_fmt()
    consistently (Joe Perches).
 
  - Clean up the generic power domains (genpd) framework somewhat
    (Aisheng Dong).
 
  - Improve kerneldoc comments for two functions in the cpufreq core
    (Rafael Wysocki).
 
  - Fix typo in a PM QoS file description comment (Aisheng Dong).
 
  - Update the handling of CPU boost frequencies in the cpupower
    utility (Abhishek Goel).
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Merge tag 'pm-5.1-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull more power management updates from Rafael Wysocki:
 "These are mostly fixes and cleanups on top of the previously merged
  power management material for 5.1-rc1 with one cpupower utility update
  that wasn't pushed earlier due to unfortunate timing.

  Specifics:

   - Fix registration of new cpuidle governors partially broken during
     the 5.0 development cycle by mistake (Rafael Wysocki).

   - Avoid integer overflows in the menu cpuidle governor by making it
     discard the overflowing data points upfront (Rafael Wysocki).

   - Fix minor mistake in the recent update of the iowait boost
     computation in the intel_pstate driver (Rafael Wysocki).

   - Drop incorrect __init annotation from one function in the pxa2xx
     cpufreq driver (Arnd Bergmann).

   - Fix the operating performance points (OPP) framework initialization
     for devices in multiple power domains if only one of them is
     scalable (Rajendra Nayak).

   - Fix mistake in dev_pm_opp_set_rate() which causes it to skip
     updating the performance state if the new frequency is the same as
     the old one (Viresh Kumar).

   - Rework the cancellation of wakeup source timers to avoid potential
     issues with it and do some cleanups unlocked by that change (Viresh
     Kumar, Rafael Wysocki).

   - Clean up the code computing the active/suspended time of devices in
     the PM-runtime framework after recent changes (Ulf Hansson).

   - Make the power management infrastructure code use pr_fmt()
     consistently (Joe Perches).

   - Clean up the generic power domains (genpd) framework somewhat
     (Aisheng Dong).

   - Improve kerneldoc comments for two functions in the cpufreq core
     (Rafael Wysocki).

   - Fix typo in a PM QoS file description comment (Aisheng Dong).

   - Update the handling of CPU boost frequencies in the cpupower
     utility (Abhishek Goel)"

* tag 'pm-5.1-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  cpuidle: governor: Add new governors to cpuidle_governors again
  cpufreq: intel_pstate: Fix up iowait_boost computation
  PM / OPP: Update performance state when freq == old_freq
  PM / wakeup: Drop wakeup_source_drop()
  PM / wakeup: Rework wakeup source timer cancellation
  PM / domains: Remove one unnecessary blank line
  PM / Domains: Return early for all errors in _genpd_power_off()
  PM / Domains: Improve warn for multiple states but no governor
  OPP: Fix handling of multiple power domains
  PM / QoS: Fix typo in file description
  cpufreq: pxa2xx: remove incorrect __init annotation
  PM-runtime: Call pm_runtime_active|suspended_time() from sysfs
  PM-runtime: Consolidate code to get active/suspended time
  PM: Add and use pr_fmt()
  cpufreq: Improve kerneldoc comments for cpufreq_cpu_get/put()
  cpuidle: menu: Avoid overflows when computing variance
  tools/power/cpupower: Display boost frequency separately
2019-03-14 10:30:06 -07:00
Joe Perches 7a5bd1279b PM: Add and use pr_fmt()
Prefix all printk/pr_<level> messages with "PM: " to make the
logging a bit more consistent.

Miscellanea:

 o Convert a few printks to pr_<level>
 o Whitespace to align to open parentheses
 o Remove embedded "PM: " from pr_debugs as pr_fmt adds it

Signed-off-by: Joe Perches <joe@perches.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Kevin Hilman <khilman@baylibre.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-03-07 11:02:02 +01:00
Linus Torvalds e431f2d74e Driver core patches for 5.1-rc1
Here is the big driver core patchset for 5.1-rc1
 
 More patches than "normal" here this merge window, due to some work in
 the driver core by Alexander Duyck to rework the async probe
 functionality to work better for a number of devices, and independant
 work from Rafael for the device link functionality to make it work
 "correctly".
 
 Also in here is:
 	- lots of BUS_ATTR() removals, the macro is about to go away
 	- firmware test fixups
 	- ihex fixups and simplification
 	- component additions (also includes i915 patches)
 	- lots of minor coding style fixups and cleanups.
 
 All of these have been in linux-next for a while with no reported
 issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-5.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core updates from Greg KH:
 "Here is the big driver core patchset for 5.1-rc1

  More patches than "normal" here this merge window, due to some work in
  the driver core by Alexander Duyck to rework the async probe
  functionality to work better for a number of devices, and independant
  work from Rafael for the device link functionality to make it work
  "correctly".

  Also in here is:

   - lots of BUS_ATTR() removals, the macro is about to go away

   - firmware test fixups

   - ihex fixups and simplification

   - component additions (also includes i915 patches)

   - lots of minor coding style fixups and cleanups.

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'driver-core-5.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (65 commits)
  driver core: platform: remove misleading err_alloc label
  platform: set of_node in platform_device_register_full()
  firmware: hardcode the debug message for -ENOENT
  driver core: Add missing description of new struct device_link field
  driver core: Fix PM-runtime for links added during consumer probe
  drivers/component: kerneldoc polish
  async: Add cmdline option to specify drivers to be async probed
  driver core: Fix possible supplier PM-usage counter imbalance
  PM-runtime: Fix __pm_runtime_set_status() race with runtime resume
  driver: platform: Support parsing GpioInt 0 in platform_get_irq()
  selftests: firmware: fix verify_reqs() return value
  Revert "selftests: firmware: remove use of non-standard diff -Z option"
  Revert "selftests: firmware: add CONFIG_FW_LOADER_USER_HELPER_FALLBACK to config"
  device: Fix comment for driver_data in struct device
  kernfs: Allocating memory for kernfs_iattrs with kmem_cache.
  sysfs: remove unused include of kernfs-internal.h
  driver core: Postpone DMA tear-down until after devres release
  driver core: Document limitation related to DL_FLAG_RPM_ACTIVE
  PM-runtime: Take suppliers into account in __pm_runtime_set_status()
  device.h: Add __cold to dev_<level> logging functions
  ...
2019-03-06 14:52:48 -08:00
Sudeep Holla 85945c28b5 PM / core: Add support to skip power management in device/driver model
All device objects in the driver model contain fields that control the
handling of various power management activities. However, it's not
always useful. There are few instances where pseudo devices are added
to the model just to take advantage of many other features like
kobjects, udev events, and so on. One such example is cpu devices and
their caches.

The sysfs for the cpu caches are managed by adding devices with cpu
as the parent in cpu_device_create() when secondary cpu is brought
online. Generally when the secondary CPUs are hotplugged back in as part
of resume from suspend-to-ram, we call cpu_device_create() from the cpu
hotplug state machine while the cpu device associated with that CPU is
not yet ready to be resumed as the device_resume() call happens bit
later. It's not really needed to set the flag is_prepared for cpu
devices as they are mostly pseudo device and hotplug framework deals
with state machine and not managed through the cpu device.

This often results in annoying warning when resuming:
Enabling non-boot CPUs ...
CPU1: Booted secondary processor
 cache: parent cpu1 should not be sleeping
CPU1 is up
CPU2: Booted secondary processor
 cache: parent cpu2 should not be sleeping
CPU2 is up
.... and so on.

So in order to fix these kind of errors, we could just completely avoid
doing any power management related initialisations and operations if
they are not used by these devices.

Add no_pm flags to indicate that the device doesn't require any sort of
PM activities and all of them can be completely skipped. We can use the
same flag to also avoid adding not used *power* sysfs entries for these
devices. For now, lets use this for cpu cache devices.

Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Tested-by: Eugeniu Rosca <erosca@de.adit-jv.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-02-19 10:42:43 +01:00
Rafael J. Wysocki 4a0fa9f9fd PM / suspend: Print debug messages for device using direct-complete
Devices using the direct-complete optimization are not present it
debug messages printed by the core device suspend and resume code,
which sometimes makes it difficult to diagnose problems related to
them, so add debug messages for those devices.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-02-13 23:19:25 +01:00
Alexander Duyck 8b9ec6b732 PM core: Use new async_schedule_dev command
Use the device specific version of the async_schedule commands to defer
various tasks related to power management. By doing this we should see a
slight improvement in performance as any device that is sensitive to
latency/locality in the setup will now be initializing on the node closest
to the device.

Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-31 14:20:54 +01:00
Lukasz Luba 6e863844ad PM: sleep: call devfreq suspend/resume
Devfreq framework supports suspend of its devices.
Call the the devfreq interface and allow devfreq devices
preserve/restore their states during suspend/resume.

Suggested-by: Tobias Jakobi <tjakobi@math.uni-bielefeld.de>
Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Lukasz Luba <l.luba@partner.samsung.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-01-02 23:07:41 +01:00