Commit graph

1158 commits

Author SHA1 Message Date
Maulik Shah
18f1f468dd PM: suspend: Set mem_sleep_current during kernel command line setup
[ Upstream commit 9bc4ffd32e ]

psci_init_system_suspend() invokes suspend_set_ops() very early during
bootup even before kernel command line for mem_sleep_default is setup.
This leads to kernel command line mem_sleep_default=s2idle not working
as mem_sleep_current gets changed to deep via suspend_set_ops() and never
changes back to s2idle.

Set mem_sleep_current along with mem_sleep_default during kernel command
line setup as default suspend mode.

Fixes: faf7ec4a92 ("drivers: firmware: psci: add system suspend support")
CC: stable@vger.kernel.org # 5.4+
Signed-off-by: Maulik Shah <quic_mkshah@quicinc.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-04-10 16:18:36 +02:00
Hongchen Zhang
4d4bf19c81 PM: hibernate: Enforce ordering during image compression/decompression
commit 71cd7e80cf upstream.

An S4 (suspend to disk) test on the LoongArch 3A6000 platform sometimes
fails with the following error messaged in the dmesg log:

	Invalid LZO compressed length

That happens because when compressing/decompressing the image, the
synchronization between the control thread and the compress/decompress/crc
thread is based on a relaxed ordering interface, which is unreliable, and the
following situation may occur:

CPU 0					CPU 1
save_image_lzo				lzo_compress_threadfn
					  atomic_set(&d->stop, 1);
  atomic_read(&data[thr].stop)
  data[thr].cmp = data[thr].cmp_len;
	  				  WRITE data[thr].cmp_len

Then CPU0 gets a stale cmp_len and writes it to disk. During resume from S4,
wrong cmp_len is loaded.

To maintain data consistency between the two threads, use the acquire/release
variants of atomic set and read operations.

Fixes: 081a9d043c ("PM / Hibernate: Improve performance of LZO/plain hibernation, checksum image")
Cc: All applicable <stable@vger.kernel.org>
Signed-off-by: Hongchen Zhang <zhanghongchen@loongson.cn>
Co-developed-by: Weihao Li <liweihao@loongson.cn>
Signed-off-by: Weihao Li <liweihao@loongson.cn>
[ rjw: Subject rewrite and changelog edits ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-23 08:54:23 +01:00
Brian Geffon
71f5344f47 PM: hibernate: Clean up sync_read handling in snapshot_write_next()
commit d08970df19 upstream.

In snapshot_write_next(), sync_read is set and unset in three different
spots unnecessiarly. As a result there is a subtle bug where the first
page after the meta data has been loaded unconditionally sets sync_read
to 0. If this first PFN was actually a highmem page, then the returned
buffer will be the global "buffer," and the page needs to be loaded
synchronously.

That is, I'm not sure we can always assume the following to be safe:

	handle->buffer = get_buffer(&orig_bm, &ca);
	handle->sync_read = 0;

Because get_buffer() can call get_highmem_page_buffer() which can
return 'buffer'.

The easiest way to address this is just set sync_read before
snapshot_write_next() returns if handle->buffer == buffer.

Signed-off-by: Brian Geffon <bgeffon@google.com>
Fixes: 8357376d3d ("[PATCH] swsusp: Improve handling of highmem")
Cc: All applicable <stable@vger.kernel.org>
[ rjw: Subject and changelog edits ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-28 16:56:29 +00:00
Brian Geffon
57dbc0eb8a PM: hibernate: Use __get_safe_page() rather than touching the list
commit f0c7183008 upstream.

We found at least one situation where the safe pages list was empty and
get_buffer() would gladly try to use a NULL pointer.

Signed-off-by: Brian Geffon <bgeffon@google.com>
Fixes: 8357376d3d ("[PATCH] swsusp: Improve handling of highmem")
Cc: All applicable <stable@vger.kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-28 16:56:29 +00:00
Imran Khan
6c073c5a5b workqueue: Introduce show_one_worker_pool and show_one_workqueue.
[ Upstream commit 55df0933be ]

Currently show_workqueue_state shows the state of all workqueues and of
all worker pools. In certain cases we may need to dump state of only a
specific workqueue or worker pool. For example in destroy_workqueue we
only need to show state of the workqueue which is getting destroyed.

So rename show_workqueue_state to show_all_workqueues(to signify it
dumps state of all busy workqueues) and divide it into more granular
functions (show_one_workqueue and show_one_worker_pool), that would show
states of individual workqueues and worker pools and can be used in
cases such as the one mentioned above.

Also, as mentioned earlier, make destroy_workqueue dump data pertaining
to only the workqueue that is being destroyed and make user(s) of
earlier interface(show_workqueue_state), use new interface
(show_all_workqueues).

Signed-off-by: Imran Khan <imran.f.khan@oracle.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Stable-dep-of: 335a42ebb0 ("workqueue: Fix hung time report of worker pools")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-05-11 23:00:35 +09:00
Greg Kroah-Hartman
84e4d4885d PM: EM: fix memory leak with using debugfs_lookup()
[ Upstream commit a0e8c13ccd ]

When calling debugfs_lookup() the result must have dput() called on it,
otherwise the memory will leak over time.  To make things simpler, just
call debugfs_lookup_and_remove() instead which handles all of the logic
at once.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-03-10 09:39:51 +01:00
xiongxin
e4d0d13b46 PM: hibernate: Fix mistake in kerneldoc comment
[ Upstream commit 6e5d7300cb ]

The actual maximum image size formula in hibernate_preallocate_memory()
is as follows:

max_size = (count - (size + PAGES_FOR_IO)) / 2
	    - 2 * DIV_ROUND_UP(reserved_size, PAGE_SIZE);

but the one in the kerneldoc comment of the function is different and
incorrect.

Fixes: ddeb648708 ("PM / Hibernate: Add sysfs knob to control size of memory for drivers")
Signed-off-by: xiongxin <xiongxin@kylinos.cn>
[ rjw: Subject and changelog rewrite ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-12-31 13:14:01 +01:00
Mario Limonciello
3436e56337 PM: hibernate: Allow hybrid sleep to work with s2idle
[ Upstream commit 85850af4fc ]

Hybrid sleep is currently hardcoded to only operate with S3 even
on systems that might not support it.

Instead of assuming this mode is what the user wants to use, for
hybrid sleep follow the setting of `mem_sleep_current` which
will respect mem_sleep_default kernel command line and policy
decisions made by the presence of the FADT low power idle bit.

Fixes: 81d45bdf89 ("PM / hibernate: Untangle power_down()")
Reported-and-tested-by: kolAflash <kolAflash@kolahilft.de>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=216574
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-03 23:59:17 +09:00
Tetsuo Handa
2f0e18e0db PM: hibernate: defer device probing when resuming from hibernation
[ Upstream commit 8386c414e2 ]

syzbot is reporting hung task at misc_open() [1], for there is a race
window of AB-BA deadlock which involves probe_count variable. Currently
wait_for_device_probe() from snapshot_open() from misc_open() can sleep
forever with misc_mtx held if probe_count cannot become 0.

When a device is probed by hub_event() work function, probe_count is
incremented before the probe function starts, and probe_count is
decremented after the probe function completed.

There are three cases that can prevent probe_count from dropping to 0.

  (a) A device being probed stopped responding (i.e. broken/malicious
      hardware).

  (b) A process emulating a USB device using /dev/raw-gadget interface
      stopped responding for some reason.

  (c) New device probe requests keeps coming in before existing device
      probe requests complete.

The phenomenon syzbot is reporting is (b). A process which is holding
system_transition_mutex and misc_mtx is waiting for probe_count to become
0 inside wait_for_device_probe(), but the probe function which is called
 from hub_event() work function is waiting for the processes which are
blocked at mutex_lock(&misc_mtx) to respond via /dev/raw-gadget interface.

This patch mitigates (b) by deferring wait_for_device_probe() from
snapshot_open() to snapshot_write() and snapshot_ioctl(). Please note that
the possibility of (b) remains as long as any thread which is emulating a
USB device via /dev/raw-gadget interface can be blocked by uninterruptible
blocking operations (e.g. mutex_lock()).

Please also note that (a) and (c) are not addressed. Regarding (c), we
should change the code to wait for only one device which contains the
image for resuming from hibernation. I don't know how to address (a), for
use of timeout for wait_for_device_probe() might result in loss of user
data in the image. Maybe we should require the userland to wait for the
image device before opening /dev/snapshot interface.

Link: https://syzkaller.appspot.com/bug?extid=358c9ab4c93da7b7238c [1]
Reported-by: syzbot <syzbot+358c9ab4c93da7b7238c@syzkaller.appspotmail.com>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Tested-by: syzbot <syzbot+358c9ab4c93da7b7238c@syzkaller.appspotmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-08-17 14:23:04 +02:00
Randy Dunlap
7e45fc93dd PM: suspend: fix return value of __setup handler
[ Upstream commit 7a64ca17e4 ]

If an invalid option is given for "test_suspend=<option>", the entire
string is added to init's environment, so return 1 instead of 0 from
the __setup handler.

  Unknown kernel command line parameters "BOOT_IMAGE=/boot/bzImage-517rc5
    test_suspend=invalid"

and

 Run /sbin/init as init process
   with arguments:
     /sbin/init
   with environment:
     HOME=/
     TERM=linux
     BOOT_IMAGE=/boot/bzImage-517rc5
     test_suspend=invalid

Fixes: 2ce986892f ("PM / sleep: Enhance test_suspend option with repeat capability")
Fixes: 27ddcc6596 ("PM / sleep: Add state field to pm_states[] entries")
Fixes: a9d7052363 ("PM: Separate suspend to RAM functionality from core")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Reported-by: Igor Zhbanov <i.zhbanov@omprussia.ru>
Link: lore.kernel.org/r/64644a2f-4a20-bab3-1e15-3b2cdd0defe3@omprussia.ru
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-04-08 14:23:07 +02:00
Randy Dunlap
d0cd9da501 PM: hibernate: fix __setup handler error handling
[ Upstream commit ba7ffcd4c4 ]

If an invalid value is used in "resumedelay=<seconds>", it is
silently ignored. Add a warning message and then let the __setup
handler return 1 to indicate that the kernel command line option
has been handled.

Fixes: 317cf7e5e8 ("PM / hibernate: convert simple_strtoul to kstrtoul")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Reported-by: Igor Zhbanov <i.zhbanov@omprussia.ru>
Link: lore.kernel.org/r/64644a2f-4a20-bab3-1e15-3b2cdd0defe3@omprussia.ru
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-04-08 14:23:07 +02:00
Rafael J. Wysocki
0e546bb132 PM: s2idle: ACPI: Fix wakeup interrupts handling
commit cb1f65c1e1 upstream.

After commit e3728b50cd ("ACPI: PM: s2idle: Avoid possible race
related to the EC GPE") wakeup interrupts occurring immediately after
the one discarded by acpi_s2idle_wake() may be missed.  Moreover, if
the SCI triggers again immediately after the rearming in
acpi_s2idle_wake(), that wakeup may be missed too.

The problem is that pm_system_irq_wakeup() only calls pm_system_wakeup()
when pm_wakeup_irq is 0, but that's not the case any more after the
interrupt causing acpi_s2idle_wake() to run until pm_wakeup_irq is
cleared by the pm_wakeup_clear() call in s2idle_loop().  However,
there may be wakeup interrupts occurring in that time frame and if
that happens, they will be missed.

To address that issue first move the clearing of pm_wakeup_irq to
the point at which it is known that the interrupt causing
acpi_s2idle_wake() to tun will be discarded, before rearming the SCI
for wakeup.  Moreover, because that only reduces the size of the
time window in which the issue may manifest itself, allow
pm_system_irq_wakeup() to register two second wakeup interrupts in
a row and, when discarding the first one, replace it with the second
one.  [Of course, this assumes that only one wakeup interrupt can be
discarded in one go, but currently that is the case and I am not
aware of any plans to change that.]

Fixes: e3728b50cd ("ACPI: PM: s2idle: Avoid possible race related to the EC GPE")
Cc: 5.4+ <stable@vger.kernel.org> # 5.4+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-02-16 12:56:19 +01:00
Amadeusz Sławiński
dc5769c7b0 PM: hibernate: Remove register_nosave_region_late()
[ Upstream commit 33569ef3c7 ]

It is an unused wrapper forcing kmalloc allocation for registering
nosave regions. Also, rename __register_nosave_region() to
register_nosave_region() now that there is no need for disambiguation.

Signed-off-by: Amadeusz Sławiński <amadeuszx.slawinski@linux.intel.com>
Reviewed-by: Cezary Rojewski <cezary.rojewski@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-02-16 12:56:15 +01:00
Greg Kroah-Hartman
fb9b60bbda PM: wakeup: simplify the output logic of pm_show_wakelocks()
commit c9d967b2ce upstream.

The buffer handling in pm_show_wakelocks() is tricky, and hopefully
correct.  Ensure it really is correct by using sysfs_emit_at() which
handles all of the tricky string handling logic in a PAGE_SIZE buffer
for us automatically as this is a sysfs file being read from.

Reviewed-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-02-01 17:27:00 +01:00
Thomas Zeitlhofer
c83f27576c PM: hibernate: use correct mode for swsusp_close()
[ Upstream commit cefcf24b4d ]

Commit 39fbef4b0f ("PM: hibernate: Get block device exclusively in
swsusp_check()") changed the opening mode of the block device to
(FMODE_READ | FMODE_EXCL).

In the corresponding calls to swsusp_close(), the mode is still just
FMODE_READ which triggers the warning in blkdev_flush_mapping() on
resume from hibernate.

So, use the mode (FMODE_READ | FMODE_EXCL) also when closing the
device.

Fixes: 39fbef4b0f ("PM: hibernate: Get block device exclusively in swsusp_check()")
Signed-off-by: Thomas Zeitlhofer <thomas.zeitlhofer+lkml@ze-it.at>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-12-01 09:04:51 +01:00
Anders Roxell
8f74e6d516 PM: hibernate: fix sparse warnings
[ Upstream commit 01de5fcd8b ]

When building the kernel with sparse enabled 'C=1' the following
warnings shows up:

kernel/power/swap.c:390:29: warning: incorrect type in assignment (different base types)
kernel/power/swap.c:390:29:    expected int ret
kernel/power/swap.c:390:29:    got restricted blk_status_t

This is due to function hib_wait_io() returns a 'blk_status_t' which is
a bitwise u8. Commit 5416da01ff ("PM: hibernate: Remove
blk_status_to_errno in hib_wait_io") seemed to have mixed up the return
type. However, the 4e4cbee93d ("block: switch bios to blk_status_t")
actually broke the behaviour by returning the wrong type.

Rework so function hib_wait_io() returns a 'int' instead of
'blk_status_t' and make sure to call function
blk_status_to_errno(hb->error)' when returning from function
hib_wait_io() a int gets returned.

Fixes: 4e4cbee93d ("block: switch bios to blk_status_t")
Fixes: 5416da01ff ("PM: hibernate: Remove blk_status_to_errno in hib_wait_io")
Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-11-18 19:16:38 +01:00
Vincent Donnefort
3c38c852c0 PM: EM: Fix inefficient states detection
[ Upstream commit aa1a43262a ]

Currently, a debug message is printed if an inefficient state is detected
in the Energy Model. Unfortunately, it won't detect if the first state is
inefficient or if two successive states are. Fix this behavior.

Fixes: 27871f7a8a (PM: Introduce an Energy Model management framework)
Signed-off-by: Vincent Donnefort <vincent.donnefort@arm.com>
Reviewed-by: Quentin Perret <qperret@google.com>
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
Reviewed-by: Matthias Kaehlcke <mka@chromium.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-11-18 19:16:30 +01:00
Ye Bin
df0b6862b7 PM: hibernate: Get block device exclusively in swsusp_check()
[ Upstream commit 39fbef4b0f ]

The following kernel crash can be triggered:

[   89.266592] ------------[ cut here ]------------
[   89.267427] kernel BUG at fs/buffer.c:3020!
[   89.268264] invalid opcode: 0000 [#1] SMP KASAN PTI
[   89.269116] CPU: 7 PID: 1750 Comm: kmmpd-loop0 Not tainted 5.10.0-862.14.0.6.x86_64-08610-gc932cda3cef4-dirty #20
[   89.273169] RIP: 0010:submit_bh_wbc.isra.0+0x538/0x6d0
[   89.277157] RSP: 0018:ffff888105ddfd08 EFLAGS: 00010246
[   89.278093] RAX: 0000000000000005 RBX: ffff888124231498 RCX: ffffffffb2772612
[   89.279332] RDX: 1ffff11024846293 RSI: 0000000000000008 RDI: ffff888124231498
[   89.280591] RBP: ffff8881248cc000 R08: 0000000000000001 R09: ffffed1024846294
[   89.281851] R10: ffff88812423149f R11: ffffed1024846293 R12: 0000000000003800
[   89.283095] R13: 0000000000000001 R14: 0000000000000000 R15: ffff8881161f7000
[   89.284342] FS:  0000000000000000(0000) GS:ffff88839b5c0000(0000) knlGS:0000000000000000
[   89.285711] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   89.286701] CR2: 00007f166ebc01a0 CR3: 0000000435c0e000 CR4: 00000000000006e0
[   89.287919] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   89.289138] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   89.290368] Call Trace:
[   89.290842]  write_mmp_block+0x2ca/0x510
[   89.292218]  kmmpd+0x433/0x9a0
[   89.294902]  kthread+0x2dd/0x3e0
[   89.296268]  ret_from_fork+0x22/0x30
[   89.296906] Modules linked in:

by running the following commands:

 1. mkfs.ext4 -O mmp  /dev/sda -b 1024
 2. mount /dev/sda /home/test
 3. echo "/dev/sda" > /sys/power/resume

That happens because swsusp_check() calls set_blocksize() on the
target partition which confuses the file system:

       Thread1                       Thread2
mount /dev/sda /home/test
get s_mmp_bh  --> has mapped flag
start kmmpd thread
				echo "/dev/sda" > /sys/power/resume
				  resume_store
				    software_resume
				      swsusp_check
				        set_blocksize
					  truncate_inode_pages_range
					    truncate_cleanup_page
					      block_invalidatepage
					        discard_buffer --> clean mapped flag
write_mmp_block
  submit_bh
    submit_bh_wbc
      BUG_ON(!buffer_mapped(bh))

To address this issue, modify swsusp_check() to open the target block
device with exclusive access.

Signed-off-by: Ye Bin <yebin10@huawei.com>
[ rjw: Subject and changelog edits ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-11-18 19:16:18 +01:00
Rafael J. Wysocki
fe583359dd Merge branches 'pm-pci', 'pm-sleep', 'pm-domains' and 'powercap'
* pm-pci:
  PCI: PM: Enable PME if it can be signaled from D3cold
  PCI: PM: Avoid forcing PCI_D0 for wakeup reasons inconsistently
  PCI: Use pci_update_current_state() in pci_enable_device_flags()

* pm-sleep:
  PM: sleep: unmark 'state' functions as kernel-doc
  PM: sleep: check RTC features instead of ops in suspend_test
  PM: sleep: s2idle: Replace deprecated CPU-hotplug functions

* pm-domains:
  PM: domains: Fix domain attach for CONFIG_PM_OPP=n
  arm64: dts: sc7180: Add required-opps for i2c
  PM: domains: Add support for 'required-opps' to set default perf state
  opp: Don't print an error if required-opps is missing

* powercap:
  powercap: Add Power Limit4 support for Alder Lake SoC
  powercap: intel_rapl: Replace deprecated CPU-hotplug functions
2021-08-30 19:25:42 +02:00
Randy Dunlap
dbcfa7156f PM: sleep: unmark 'state' functions as kernel-doc
Fix kernel-doc warnings in kernel/power/main.c by unmarking the
comment block as kernel-doc notation. This eliminates the following
kernel-doc warnings:

kernel/power/main.c:593: warning: expecting prototype for state(). Prototype was for state_show() instead
kernel/power/main.c:593: warning: Function parameter or member 'kobj' not described in 'state_show'
kernel/power/main.c:593: warning: Function parameter or member 'attr' not described in 'state_show'
kernel/power/main.c:593: warning: Function parameter or member 'buf' not described in 'state_show'

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-08-16 18:49:39 +02:00
Lukasz Luba
7fcc17d0cb PM: EM: Increase energy calculation precision
The Energy Model (EM) provides useful information about device power in
each performance state to other subsystems like: Energy Aware Scheduler
(EAS). The energy calculation in EAS does arithmetic operation based on
the EM em_cpu_energy(). Current implementation of that function uses
em_perf_state::cost as a pre-computed cost coefficient equal to:
cost = power * max_frequency / frequency.
The 'power' is expressed in milli-Watts (or in abstract scale).

There are corner cases when the EAS energy calculation for two Performance
Domains (PDs) return the same value. The EAS compares these values to
choose smaller one. It might happen that this values are equal due to
rounding error. In such scenario, we need better resolution, e.g. 1000
times better. To provide this possibility increase the resolution in the
em_perf_state::cost for 64-bit architectures. The cost of increasing
resolution on 32-bit is pretty high (64-bit division) and is not justified
since there are no new 32bit big.LITTLE EAS systems expected which would
benefit from this higher resolution.

This patch allows to avoid the rounding to milli-Watt errors, which might
occur in EAS energy estimation for each PD. The rounding error is common
for small tasks which have small utilization value.

There are two places in the code where it makes a difference:
1. In the find_energy_efficient_cpu() where we are searching for
best_delta. We might suffer there when two PDs return the same result,
like in the example below.

Scenario:
Low utilized system e.g. ~200 sum_util for PD0 and ~220 for PD1. There
are quite a few small tasks ~10-15 util. These tasks would suffer for
the rounding error. These utilization values are typical when running games
on Android. One of our partners has reported 5..10mA less battery drain
when running with increased resolution.

Some details:
We have two PDs: PD0 (big) and PD1 (little)
Let's compare w/o patch set ('old') and w/ patch set ('new')
We are comparing energy w/ task and w/o task placed in the PDs

a) 'old' w/o patch set, PD0
task_util = 13
cost = 480
sum_util_w/o_task = 215
sum_util_w_task = 228
scale_cpu = 1024
energy_w/o_task = 480 * 215 / 1024 = 100.78 => 100
energy_w_task = 480 * 228 / 1024 = 106.87 => 106
energy_diff = 106 - 100 = 6
(this is equal to 'old' PD1's energy_diff in 'c)')

b) 'new' w/ patch set, PD0
task_util = 13
cost = 480 * 1000 = 480000
sum_util_w/o_task = 215
sum_util_w_task = 228
energy_w/o_task = 480000 * 215 / 1024 = 100781
energy_w_task = 480000 * 228 / 1024  = 106875
energy_diff = 106875 - 100781 = 6094
(this is not equal to 'new' PD1's energy_diff in 'd)')

c) 'old' w/o patch set, PD1
task_util = 13
cost = 160
sum_util_w/o_task = 283
sum_util_w_task = 293
scale_cpu = 355
energy_w/o_task = 160 * 283 / 355 = 127.55 => 127
energy_w_task = 160 * 296 / 355 = 133.41 => 133
energy_diff = 133 - 127 = 6
(this is equal to 'old' PD0's energy_diff in 'a)')

d) 'new' w/ patch set, PD1
task_util = 13
cost = 160 * 1000 = 160000
sum_util_w/o_task = 283
sum_util_w_task = 293
scale_cpu = 355
energy_w/o_task = 160000 * 283 / 355 = 127549
energy_w_task = 160000 * 296 / 355 =   133408
energy_diff = 133408 - 127549 = 5859
(this is not equal to 'new' PD0's energy_diff in 'b)')

2. Difference in the 6% energy margin filter at the end of
find_energy_efficient_cpu(). With this patch the margin comparison also
has better resolution, so it's possible to have better task placement
thanks to that.

Fixes: 27871f7a8a ("PM: Introduce an Energy Model management framework")
Reported-by: CCJ Yeh <CCj.Yeh@mediatek.com>
Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-08-06 15:30:42 +02:00
Alexandre Belloni
4fac49fd0a PM: sleep: check RTC features instead of ops in suspend_test
Test RTC_FEATURE_ALARM instead of relying on ops->set_alarm to know whether
alarms are available.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-08-04 20:23:05 +02:00
Sebastian Andrzej Siewior
d2c8cce647 PM: sleep: s2idle: Replace deprecated CPU-hotplug functions
The functions get_online_cpus() and put_online_cpus() have been
deprecated during the CPU hotplug rework. They map directly to
cpus_read_lock() and cpus_read_unlock().

Replace deprecated CPU-hotplug functions with the official version.
The behavior remains unchanged.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-08-04 20:18:13 +02:00
Mike Rapoport
9a436f8ff6 PM: hibernate: disable when there are active secretmem users
It is unsafe to allow saving of secretmem areas to the hibernation
snapshot as they would be visible after the resume and this essentially
will defeat the purpose of secret memory mappings.

Prevent hibernation whenever there are active secret memory users.

Link: https://lkml.kernel.org/r/20210518072034.31572-6-rppt@kernel.org
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christopher Lameter <cl@linux.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Elena Reshetova <elena.reshetova@intel.com>
Cc: Hagen Paul Pfeifer <hagen@jauu.net>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Bottomley <jejb@linux.ibm.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Palmer Dabbelt <palmerdabbelt@google.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rick Edgecombe <rick.p.edgecombe@intel.com>
Cc: Roman Gushchin <guro@fb.com>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tycho Andersen <tycho@tycho.ws>
Cc: Will Deacon <will@kernel.org>
Cc: kernel test robot <lkp@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-07-08 11:48:21 -07:00
Zhen Lei
480f0de68c PM: hibernate: remove leading spaces before tabs
1) Run the following command to find and remove the leading spaces
    before tabs:
    $ find kernel/power/ -type f | xargs sed -r -i 's/^[ ]+\t/\t/'
 2) Manually check and correct if necessary

Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-06-11 18:52:05 +02:00
Zhen Lei
03466883a0 PM: sleep: remove trailing spaces and tabs
Run the following command to find and remove the trailing spaces and tabs:

$ find kernel/power/ -type f | xargs sed -r -i 's/[ \t]+$//'

Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-06-11 18:49:09 +02:00
Zhen Lei
6be2408a1e PM: hibernate: fix spelling mistakes
Fix some spelling mistakes in comments:

corresonds ==> corresponds
alocated ==> allocated
unitialized ==> uninitialized
Deompression ==> Decompression

Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-05-24 16:17:07 +02:00
Lu Jialin
e4b2897ae1 PM: sleep: fix typos in comments
Change "occured" to "occurred" in kernel/power/autosleep.c.

Change "consiting" to "consisting" in kernel/power/snapshot.c.

Change "avaiable" to "available" in kernel/power/swap.c.

No functionality changed.

Signed-off-by: Lu Jialin <lujialin4@huawei.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-04-08 19:37:21 +02:00
Lukasz Luba
fb9d62b27a PM: EM: postpone creating the debugfs dir till fs_initcall
The debugfs directory '/sys/kernel/debug/energy_model' is needed before
the Energy Model registration can happen. With the recent change in
debugfs subsystem it's not allowed to create this directory at early
stage (core_initcall). Thus creating this directory would fail.

Postpone the creation of the EM debug dir to later stage: fs_initcall.

It should be safe since all clients: CPUFreq drivers, Devfreq drivers
will be initialized in later stages.

The custom debug log below prints the time of creation the EM debug dir
at fs_initcall and successful registration of EMs at later stages.

[    1.505717] energy_model: creating rootdir
[    3.698307] cpu cpu0: EM: created perf domain
[    3.709022] cpu cpu1: EM: created perf domain

Fixes: 56348560d4 ("debugfs: do not attempt to create a new file before the filesystem is initalized")
Reported-by: Ionela Voinescu <ionela.voinescu@arm.com>
Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-03-23 19:53:48 +01:00
Rafael J. Wysocki
a9a939cb34 Merge branches 'powercap' and 'pm-misc'
* powercap:
  powercap: intel_rapl: Use topology interface in rapl_init_domains()
  powercap: intel_rapl: Use topology interface in rapl_add_package()
  powercap/intel_rapl: add support for AlderLake Mobile
  powercap/drivers/dtpm: Fix size of object being allocated
  powercap/drivers/dtpm: Fix an IS_ERR() vs NULL check
  powercap/drivers/dtpm: Fix some missing unlock bugs
  powercap/drivers/dtpm: Fix a double shift bug
  powercap/drivers/dtpm: Fix __udivdi3 and __aeabi_uldivmod unresolved symbols
  powercap/drivers/dtpm: Add CPU energy model based support
  powercap/drivers/dtpm: Add API for dynamic thermal power management
  Documentation/powercap/dtpm: Add documentation for dtpm
  units: Add Watt units

* pm-misc:
  PM: Kconfig: remove unneeded "default n" options
  PM: EM: update Kconfig description and drop "default n" option
2021-02-15 18:50:01 +01:00
Rikard Falkeborn
1556057413 PM: sleep: Constify static struct attribute_group
The only usage of suspend_attr_group is to put its address in an
array of pointers to const attribute_group structs.

Make it const to allow the compiler to put it into read-only memory.

Signed-off-by: Rikard Falkeborn <rikard.falkeborn@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-02-12 16:46:59 +01:00
Lukasz Luba
c4cc3141b6 PM: Kconfig: remove unneeded "default n" options
Remove "default n" options. If the "default" line is removed, it
defaults to 'n'.

Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-02-12 16:43:23 +01:00
Lukasz Luba
3af2f0aa2e PM: EM: update Kconfig description and drop "default n" option
Energy Model supports now other devices like GPUs, DSPs, not only CPUs.
Thus, update the description in the config option. Remove also unneeded
"default n". If the "default" line is removed, it defaults to 'n'.

Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-02-12 16:43:23 +01:00
Zqiang
ccf7ce46ab PM: sleep: No need to check PF_WQ_WORKER in thaw_kernel_threads()
Because PF_KTHREAD is set for all wq worker threads, it is
not necessary to check PF_WQ_WORKER in addition to it in
thaw_kernel_threads(), so stop doing that.

Signed-off-by: Zqiang <qiang.zhang@windriver.com>
[ rjw: Subject and changelog rewrite ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-01-27 19:20:17 +01:00
Laurent Badel
fef9c8d28e PM: hibernate: flush swap writer after marking
Flush the swap writer after, not before, marking the files, to ensure the
signature is properly written.

Fixes: 6f612af578 ("PM / Hibernate: Group swap ops")
Signed-off-by: Laurent Badel <laurentbadel@eaton.com>
Cc: All applicable <stable@vger.kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-01-25 18:52:30 +01:00
Linus Torvalds
b4ec805464 Power management updates for 5.11-rc1
- Use local_clock() instead of jiffies in the cpufreq statistics to
    improve accuracy (Viresh Kumar).
 
  - Fix up OPP usage in the cpufreq-dt and qcom-cpufreq-nvmem cpufreq
    drivers (Viresh Kumar).
 
  - Clean up the cpufreq core, the intel_pstate driver and the
    schedutil cpufreq governor (Rafael Wysocki).
 
  - Fix up error code paths in the sti-cpufreq and mediatek cpufreq
    drivers (Yangtao Li, Qinglang Miao).
 
  - Fix cpufreq_online() to return error codes instead of success (0)
    in all cases when it fails (Wang ShaoBo).
 
  - Add mt8167 support to the mediatek cpufreq driver and blacklist
    mt8516 in the cpufreq-dt-platdev driver (Fabien Parent).
 
  - Modify the tegra194 cpufreq driver to always return values from
    the frequency table as the current frequency and clean up that
    driver (Sumit Gupta, Jon Hunter).
 
  - Modify the arm_scmi cpufreq driver to allow it to discover the
    power scale present in the performance protocol and provide this
    information to the Energy Model (Lukasz Luba).
 
  - Add missing MODULE_DEVICE_TABLE to several cpufreq drivers (Pali
    Rohár).
 
  - Clean up the CPPC cpufreq driver (Ionela Voinescu).
 
  - Fix NVMEM_IMX_OCOTP dependency in the imx cpufreq driver (Arnd
    Bergmann).
 
  - Rework the poling interval selection for the polling state in
    cpuidle (Mel Gorman).
 
  - Enable suspend-to-idle for PSCI OSI mode in the PSCI cpuidle
    driver (Ulf Hansson).
 
  - Modify the OPP framework to support empty (node-less) OPP tables
    in DT for passing dependency information (Nicola Mazzucato).
 
  - Fix potential lockdep issue in the OPP core and clean up the OPP
    core (Viresh Kumar).
 
  - Modify dev_pm_opp_put_regulators() to accept a NULL argument and
    update its users accordingly (Viresh Kumar).
 
  - Add frequency changes tracepoint to devfreq (Matthias Kaehlcke).
 
  - Add support for governor feature flags to devfreq, make devfreq
    sysfs file permissions depend on the governor and clean up the
    devfreq core (Chanwoo Choi).
 
  - Clean up the tegra20 devfreq driver and deprecate it to allow
    another driver based on EMC_STAT to be used instead of it (Dmitry
    Osipenko).
 
  - Add interconnect support to the tegra30 devfreq driver, allow it
    to take the interconnect and OPP information from DT and clean it
    up ((Dmitry Osipenko).
 
  - Add interconnect support to the exynos-bus devfreq driver along
    with interconnect properties documentation (Sylwester Nawrocki).
 
  - Add suport for AMD Fam17h and Fam19h processors to the RAPL power
    capping driver (Victor Ding, Kim Phillips).
 
  - Fix handling of overly long constraint names in the powercap
    framework (Lukasz Luba).
 
  - Fix the wakeup configuration handling for bridges in the ACPI
    device power management core (Rafael Wysocki).
 
  - Add support for using an abstract scale for power units in the
    Energy Model (EM) and document it (Lukasz Luba).
 
  - Add em_cpu_energy() micro-optimization to the EM (Pavankumar
    Kondeti).
 
  - Modify the generic power domains (genpd) framwework to support
    suspend-to-idle (Ulf Hansson).
 
  - Fix creation of debugfs nodes in genpd (Thierry Strudel).
 
  - Clean up genpd (Lina Iyer).
 
  - Clean up the core system-wide suspend code and make it print
    driver flags for devices with debug enabled (Alex Shi, Patrice
    Chotard, Chen Yu).
 
  - Modify the ACPI system reboot code to make it prepare for system
    power off to avoid confusing the platform firmware (Kai-Heng Feng).
 
  - Update the pm-graph (multiple changes, mostly usability-related)
    and cpupower (online and offline CPU information support) PM
    utilities (Todd Brandt, Brahadambal Srinivasan).
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Merge tag 'pm-5.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull power management updates from Rafael Wysocki:
 "These update cpufreq (core and drivers), cpuidle (polling state
  implementation and the PSCI driver), the OPP (operating performance
  points) framework, devfreq (core and drivers), the power capping RAPL
  (Running Average Power Limit) driver, the Energy Model support, the
  generic power domains (genpd) framework, the ACPI device power
  management, the core system-wide suspend code and power management
  utilities.

  Specifics:

   - Use local_clock() instead of jiffies in the cpufreq statistics to
     improve accuracy (Viresh Kumar).

   - Fix up OPP usage in the cpufreq-dt and qcom-cpufreq-nvmem cpufreq
     drivers (Viresh Kumar).

   - Clean up the cpufreq core, the intel_pstate driver and the
     schedutil cpufreq governor (Rafael Wysocki).

   - Fix up error code paths in the sti-cpufreq and mediatek cpufreq
     drivers (Yangtao Li, Qinglang Miao).

   - Fix cpufreq_online() to return error codes instead of success (0)
     in all cases when it fails (Wang ShaoBo).

   - Add mt8167 support to the mediatek cpufreq driver and blacklist
     mt8516 in the cpufreq-dt-platdev driver (Fabien Parent).

   - Modify the tegra194 cpufreq driver to always return values from the
     frequency table as the current frequency and clean up that driver
     (Sumit Gupta, Jon Hunter).

   - Modify the arm_scmi cpufreq driver to allow it to discover the
     power scale present in the performance protocol and provide this
     information to the Energy Model (Lukasz Luba).

   - Add missing MODULE_DEVICE_TABLE to several cpufreq drivers (Pali
     Rohár).

   - Clean up the CPPC cpufreq driver (Ionela Voinescu).

   - Fix NVMEM_IMX_OCOTP dependency in the imx cpufreq driver (Arnd
     Bergmann).

   - Rework the poling interval selection for the polling state in
     cpuidle (Mel Gorman).

   - Enable suspend-to-idle for PSCI OSI mode in the PSCI cpuidle driver
     (Ulf Hansson).

   - Modify the OPP framework to support empty (node-less) OPP tables in
     DT for passing dependency information (Nicola Mazzucato).

   - Fix potential lockdep issue in the OPP core and clean up the OPP
     core (Viresh Kumar).

   - Modify dev_pm_opp_put_regulators() to accept a NULL argument and
     update its users accordingly (Viresh Kumar).

   - Add frequency changes tracepoint to devfreq (Matthias Kaehlcke).

   - Add support for governor feature flags to devfreq, make devfreq
     sysfs file permissions depend on the governor and clean up the
     devfreq core (Chanwoo Choi).

   - Clean up the tegra20 devfreq driver and deprecate it to allow
     another driver based on EMC_STAT to be used instead of it (Dmitry
     Osipenko).

   - Add interconnect support to the tegra30 devfreq driver, allow it to
     take the interconnect and OPP information from DT and clean it up
     (Dmitry Osipenko).

   - Add interconnect support to the exynos-bus devfreq driver along
     with interconnect properties documentation (Sylwester Nawrocki).

   - Add suport for AMD Fam17h and Fam19h processors to the RAPL power
     capping driver (Victor Ding, Kim Phillips).

   - Fix handling of overly long constraint names in the powercap
     framework (Lukasz Luba).

   - Fix the wakeup configuration handling for bridges in the ACPI
     device power management core (Rafael Wysocki).

   - Add support for using an abstract scale for power units in the
     Energy Model (EM) and document it (Lukasz Luba).

   - Add em_cpu_energy() micro-optimization to the EM (Pavankumar
     Kondeti).

   - Modify the generic power domains (genpd) framwework to support
     suspend-to-idle (Ulf Hansson).

   - Fix creation of debugfs nodes in genpd (Thierry Strudel).

   - Clean up genpd (Lina Iyer).

   - Clean up the core system-wide suspend code and make it print driver
     flags for devices with debug enabled (Alex Shi, Patrice Chotard,
     Chen Yu).

   - Modify the ACPI system reboot code to make it prepare for system
     power off to avoid confusing the platform firmware (Kai-Heng Feng).

   - Update the pm-graph (multiple changes, mostly usability-related)
     and cpupower (online and offline CPU information support) PM
     utilities (Todd Brandt, Brahadambal Srinivasan)"

* tag 'pm-5.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (86 commits)
  cpufreq: Fix cpufreq_online() return value on errors
  cpufreq: Fix up several kerneldoc comments
  cpufreq: stats: Use local_clock() instead of jiffies
  cpufreq: schedutil: Simplify sugov_update_next_freq()
  cpufreq: intel_pstate: Simplify intel_cpufreq_update_pstate()
  PM: domains: create debugfs nodes when adding power domains
  opp: of: Allow empty opp-table with opp-shared
  dt-bindings: opp: Allow empty OPP tables
  media: venus: dev_pm_opp_put_*() accepts NULL argument
  drm/panfrost: dev_pm_opp_put_*() accepts NULL argument
  drm/lima: dev_pm_opp_put_*() accepts NULL argument
  PM / devfreq: exynos: dev_pm_opp_put_*() accepts NULL argument
  cpufreq: qcom-cpufreq-nvmem: dev_pm_opp_put_*() accepts NULL argument
  cpufreq: dt: dev_pm_opp_put_regulators() accepts NULL argument
  opp: Allow dev_pm_opp_put_*() APIs to accept NULL opp_table
  opp: Don't create an OPP table from dev_pm_opp_get_opp_table()
  cpufreq: dt: Don't (ab)use dev_pm_opp_get_opp_table() to create OPP table
  opp: Reduce the size of critical section in _opp_kref_release()
  PM / EM: Micro optimization in em_cpu_energy
  cpufreq: arm_scmi: Discover the power scale in performance protocol
  ...
2020-12-15 16:30:31 -08:00
Vlastimil Babka
03b6c9a3e8 kernel/power: allow hibernation with page_poison sanity checking
Page poisoning used to be incompatible with hibernation, as the state of
poisoned pages was lost after resume, thus enabling CONFIG_HIBERNATION
forces CONFIG_PAGE_POISONING_NO_SANITY.  For the same reason, the
poisoning with zeroes variant CONFIG_PAGE_POISONING_ZERO used to disable
hibernation.  The latter restriction was removed by commit 1ad1410f63
("PM / Hibernate: allow hibernation with PAGE_POISONING_ZERO") and
similarly for init_on_free by commit 18451f9f9e ("PM: hibernate: fix
crashes with init_on_free=1") by making sure free pages are cleared after
resume.

We can use the same mechanism to instead poison free pages with
PAGE_POISON after resume.  This covers both zero and 0xAA patterns.  Thus
we can remove the Kconfig restriction that disables page poison sanity
checking when hibernation is enabled.

Link: https://lkml.kernel.org/r/20201113104033.22907-4-vbabka@suse.cz
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>	[hibernation]
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Laura Abbott <labbott@kernel.org>
Cc: Mateusz Nosek <mateusznosek0@gmail.com>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-12-15 12:13:46 -08:00
Mike Rapoport
2abf962a8d PM: hibernate: make direct map manipulations more explicit
When DEBUG_PAGEALLOC or ARCH_HAS_SET_DIRECT_MAP is enabled a page may be
not present in the direct map and has to be explicitly mapped before it
could be copied.

Introduce hibernate_map_page() and hibernation_unmap_page() that will
explicitly use set_direct_map_{default,invalid}_noflush() for
ARCH_HAS_SET_DIRECT_MAP case and debug_pagealloc_{map,unmap}_pages() for
DEBUG_PAGEALLOC case.

The remapping of the pages in safe_copy_page() presumes that it only
changes protection bits in an existing PTE and so it is safe to ignore
return value of set_direct_map_{default,invalid}_noflush().

Still, add a pr_warn() so that future changes in set_memory APIs will not
silently break hibernation.

Link: https://lkml.kernel.org/r/20201109192128.960-3-rppt@kernel.org
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: "Edgecombe, Rick P" <rick.p.edgecombe@intel.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Len Brown <len.brown@intel.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-12-15 12:13:43 -08:00
Rafael J. Wysocki
42b4ca04cb Merge branches 'pm-sleep', 'pm-acpi', 'pm-domains' and 'powercap'
* pm-sleep:
  PM: sleep: Add dev_wakeup_path() helper
  PM / suspend: fix kernel-doc markup
  PM: sleep: Print driver flags for all devices during suspend/resume

* pm-acpi:
  PM: ACPI: Refresh wakeup device power configuration every time
  PM: ACPI: PCI: Drop acpi_pm_set_bridge_wakeup()
  PM: ACPI: reboot: Use S5 for reboot

* pm-domains:
  PM: domains: create debugfs nodes when adding power domains
  PM: domains: replace -ENOTSUPP with -EOPNOTSUPP

* powercap:
  powercap: Adjust printing the constraint name with new line
  powercap: RAPL: Add AMD Fam19h RAPL support
  powercap: Add AMD Fam17h RAPL support
  powercap/intel_rapl_msr: Convert rapl_msr_priv into pointer
  x86/msr-index: sort AMD RAPL MSRs by address
2020-12-15 15:26:14 +01:00
Alex Shi
ab150c3f80 PM / suspend: fix kernel-doc markup
Add parameter explanation to fix kernel-doc marks:

kernel/power/suspend.c:233: warning: Function parameter or member
'state' not described in 'suspend_valid_only_mem'
kernel/power/suspend.c:344: warning: Function parameter or member
'state' not described in 'suspend_prepare'

Signed-off-by: Alex Shi <alex.shi@linux.alibaba.com>
[ rjw: Change the proposed parameter descriptions. ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-11-23 18:24:53 +01:00
Lukasz Luba
f2c90b12e7 PM: EM: update the comments related to power scale
The Energy Model supports power values expressed in milli-Watts or in an
'abstract scale'. Update the related comments is the code to reflect that
state.

Reviewed-by: Quentin Perret <qperret@google.com>
Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-11-10 20:29:28 +01:00
Lukasz Luba
c250d50fe2 PM: EM: Add a flag indicating units of power values in Energy Model
There are different platforms and devices which might use different scale
for the power values. Kernel sub-systems might need to check if all
Energy Model (EM) devices are using the same scale. Address that issue and
store the information inside EM for each device. Thanks to that they can
be easily compared and proper action triggered.

Suggested-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: Quentin Perret <qperret@google.com>
Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-11-10 20:22:00 +01:00
Jackie Zamow
4d4ce8053b PM: sleep: fix typo in kernel/power/process.c
Fix a typo in a comment in freeze_processes().

Signed-off-by: Jackie Zamow <jackie.zamow@gmail.com>
[ rjw: Subject and changelog edits ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-10-27 19:11:44 +01:00
Randy Dunlap
7b7b8a2c95 kernel/: fix repeated words in comments
Fix multiple occurrences of duplicated words in kernel/.

Fix one typo/spello on the same line as a duplicate word.  Change one
instance of "the the" to "that the".  Otherwise just drop one of the
repeated words.

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Link: https://lkml.kernel.org/r/98202fa6-8919-ef63-9efe-c0fad5ca7af1@infradead.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-16 11:11:19 -07:00
Linus Torvalds
0b8417c141 Power management updates for 5.10-rc1
- Rework cpufreq statistics collection to allow it to take place
    when fast frequency switching is enabled in the governor (Viresh
    Kumar).
 
  - Make the cpufreq core set the frequency scale on behalf of the
    driver and update several cpufreq drivers accordingly (Ionela
    Voinescu, Valentin Schneider).
 
  - Add new hardware support to the STI and qcom cpufreq drivers and
    improve them (Alain Volmat, Manivannan Sadhasivam).
 
  - Fix multiple assorted issues in cpufreq drivers (Jon Hunter,
    Krzysztof Kozlowski, Matthias Kaehlcke, Pali Rohár, Stephan
    Gerhold, Viresh Kumar).
 
  - Fix several assorted issues in the operating performance points
    (OPP) framework (Stephan Gerhold, Viresh Kumar).
 
  - Allow devfreq drivers to fetch devfreq instances by DT enumeration
    instead of using explicit phandles and modify the devfreq core
    code to support driver-specific devfreq DT bindings (Leonard
    Crestez, Chanwoo Choi).
 
  - Improve initial hardware resetting in the tegra30 devfreq driver
    and clean up the tegra cpuidle driver (Dmitry Osipenko).
 
  - Update the cpuidle core to collect state entry rejection
    statistics and expose them via sysfs (Lina Iyer).
 
  - Improve the ACPI _CST code handling diagnostics (Chen Yu).
 
  - Update the PSCI cpuidle driver to allow the PM domain
    initialization to occur in the OSI mode as well as in the PC
    mode (Ulf Hansson).
 
  - Rework the generic power domains (genpd) core code to allow
    domain power off transition to be aborted in the absence of the
    "power off" domain callback (Ulf Hansson).
 
  - Fix two suspend-to-idle issues in the ACPI EC driver (Rafael
    Wysocki).
 
  - Fix the handling of timer_expires in the PM-runtime framework on
    32-bit systems and the handling of device links in it (Grygorii
    Strashko, Xiang Chen).
 
  - Add IO requests batching support to the hibernate image saving and
    reading code and drop a bogus get_gendisk() from there (Xiaoyi
    Chen, Christoph Hellwig).
 
  - Allow PCIe ports to be put into the D3cold power state if they
    are power-manageable via ACPI (Lukas Wunner).
 
  - Add missing header file include to a power capping driver (Pujin
    Shi).
 
  - Clean up the qcom-cpr AVS driver a bit (Liu Shixin).
 
  - Kevin Hilman steps down as designated reviwer of adaptive voltage
    scaling (AVS) driverrs (Kevin Hilman).
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Merge tag 'pm-5.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull power management updates from Rafael Wysocki:
 "These rework the collection of cpufreq statistics to allow it to take
  place if fast frequency switching is enabled in the governor, rework
  the frequency invariance handling in the cpufreq core and drivers, add
  new hardware support to a couple of cpufreq drivers, fix a number of
  assorted issues and clean up the code all over.

  Specifics:

   - Rework cpufreq statistics collection to allow it to take place when
     fast frequency switching is enabled in the governor (Viresh Kumar).

   - Make the cpufreq core set the frequency scale on behalf of the
     driver and update several cpufreq drivers accordingly (Ionela
     Voinescu, Valentin Schneider).

   - Add new hardware support to the STI and qcom cpufreq drivers and
     improve them (Alain Volmat, Manivannan Sadhasivam).

   - Fix multiple assorted issues in cpufreq drivers (Jon Hunter,
     Krzysztof Kozlowski, Matthias Kaehlcke, Pali Rohár, Stephan
     Gerhold, Viresh Kumar).

   - Fix several assorted issues in the operating performance points
     (OPP) framework (Stephan Gerhold, Viresh Kumar).

   - Allow devfreq drivers to fetch devfreq instances by DT enumeration
     instead of using explicit phandles and modify the devfreq core code
     to support driver-specific devfreq DT bindings (Leonard Crestez,
     Chanwoo Choi).

   - Improve initial hardware resetting in the tegra30 devfreq driver
     and clean up the tegra cpuidle driver (Dmitry Osipenko).

   - Update the cpuidle core to collect state entry rejection statistics
     and expose them via sysfs (Lina Iyer).

   - Improve the ACPI _CST code handling diagnostics (Chen Yu).

   - Update the PSCI cpuidle driver to allow the PM domain
     initialization to occur in the OSI mode as well as in the PC mode
     (Ulf Hansson).

   - Rework the generic power domains (genpd) core code to allow domain
     power off transition to be aborted in the absence of the "power
     off" domain callback (Ulf Hansson).

   - Fix two suspend-to-idle issues in the ACPI EC driver (Rafael
     Wysocki).

   - Fix the handling of timer_expires in the PM-runtime framework on
     32-bit systems and the handling of device links in it (Grygorii
     Strashko, Xiang Chen).

   - Add IO requests batching support to the hibernate image saving and
     reading code and drop a bogus get_gendisk() from there (Xiaoyi
     Chen, Christoph Hellwig).

   - Allow PCIe ports to be put into the D3cold power state if they are
     power-manageable via ACPI (Lukas Wunner).

   - Add missing header file include to a power capping driver (Pujin
     Shi).

   - Clean up the qcom-cpr AVS driver a bit (Liu Shixin).

   - Kevin Hilman steps down as designated reviwer of adaptive voltage
     scaling (AVS) drivers (Kevin Hilman)"

* tag 'pm-5.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (65 commits)
  cpufreq: stats: Fix string format specifier mismatch
  arm: disable frequency invariance for CONFIG_BL_SWITCHER
  cpufreq,arm,arm64: restructure definitions of arch_set_freq_scale()
  cpufreq: stats: Add memory barrier to store_reset()
  cpufreq: schedutil: Simplify sugov_fast_switch()
  ACPI: EC: PM: Drop ec_no_wakeup check from acpi_ec_dispatch_gpe()
  ACPI: EC: PM: Flush EC work unconditionally after wakeup
  PCI/ACPI: Whitelist hotplug ports for D3 if power managed by ACPI
  PM: hibernate: remove the bogus call to get_gendisk() in software_resume()
  cpufreq: Move traces and update to policy->cur to cpufreq core
  cpufreq: stats: Enable stats for fast-switch as well
  cpufreq: stats: Mark few conditionals with unlikely()
  cpufreq: stats: Remove locking
  cpufreq: stats: Defer stats update to cpufreq_stats_record_transition()
  PM: domains: Allow to abort power off when no ->power_off() callback
  PM: domains: Rename power state enums for genpd
  PM / devfreq: tegra30: Improve initial hardware resetting
  PM / devfreq: event: Change prototype of devfreq_event_get_edev_by_phandle function
  PM / devfreq: Change prototype of devfreq_get_devfreq_by_phandle function
  PM / devfreq: Add devfreq_get_devfreq_by_node function
  ...
2020-10-14 10:45:41 -07:00
Linus Torvalds
3ad11d7ac8 block-5.10-2020-10-12
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Merge tag 'block-5.10-2020-10-12' of git://git.kernel.dk/linux-block

Pull block updates from Jens Axboe:

 - Series of merge handling cleanups (Baolin, Christoph)

 - Series of blk-throttle fixes and cleanups (Baolin)

 - Series cleaning up BDI, seperating the block device from the
   backing_dev_info (Christoph)

 - Removal of bdget() as a generic API (Christoph)

 - Removal of blkdev_get() as a generic API (Christoph)

 - Cleanup of is-partition checks (Christoph)

 - Series reworking disk revalidation (Christoph)

 - Series cleaning up bio flags (Christoph)

 - bio crypt fixes (Eric)

 - IO stats inflight tweak (Gabriel)

 - blk-mq tags fixes (Hannes)

 - Buffer invalidation fixes (Jan)

 - Allow soft limits for zone append (Johannes)

 - Shared tag set improvements (John, Kashyap)

 - Allow IOPRIO_CLASS_RT for CAP_SYS_NICE (Khazhismel)

 - DM no-wait support (Mike, Konstantin)

 - Request allocation improvements (Ming)

 - Allow md/dm/bcache to use IO stat helpers (Song)

 - Series improving blk-iocost (Tejun)

 - Various cleanups (Geert, Damien, Danny, Julia, Tetsuo, Tian, Wang,
   Xianting, Yang, Yufen, yangerkun)

* tag 'block-5.10-2020-10-12' of git://git.kernel.dk/linux-block: (191 commits)
  block: fix uapi blkzoned.h comments
  blk-mq: move cancel of hctx->run_work to the front of blk_exit_queue
  blk-mq: get rid of the dead flush handle code path
  block: get rid of unnecessary local variable
  block: fix comment and add lockdep assert
  blk-mq: use helper function to test hw stopped
  block: use helper function to test queue register
  block: remove redundant mq check
  block: invoke blk_mq_exit_sched no matter whether have .exit_sched
  percpu_ref: don't refer to ref->data if it isn't allocated
  block: ratelimit handle_bad_sector() message
  blk-throttle: Re-use the throtl_set_slice_end()
  blk-throttle: Open code __throtl_de/enqueue_tg()
  blk-throttle: Move service tree validation out of the throtl_rb_first()
  blk-throttle: Move the list operation after list validation
  blk-throttle: Fix IO hang for a corner case
  blk-throttle: Avoid tracking latency if low limit is invalid
  blk-throttle: Avoid getting the current time if tg->last_finish_time is 0
  blk-throttle: Remove a meaningless parameter for throtl_downgrade_state()
  block: Remove redundant 'return' statement
  ...
2020-10-13 12:12:44 -07:00
Christoph Hellwig
428805c0c5 PM: hibernate: remove the bogus call to get_gendisk() in software_resume()
get_gendisk grabs a reference on the disk and file operation, so this
code will leak both of them while having absolutely no use for the
gendisk itself.

This effectively reverts commit 2df83fa4bc ("PM / Hibernate: Use
get_gendisk to verify partition if resume_file is integer format")

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-10-05 18:42:58 +02:00
Xiaoyi Chen
55c4478a8f PM: hibernate: Batch hibernate and resume IO requests
Hibernate and resume process submits individual IO requests for each page
of the data, so use blk_plug to improve the batching of these requests.

Testing this change with hibernate and resumes consistently shows merging
of the IO requests and more than an order of magnitude improvement in
hibernate and resume speed is observed.

One hibernate and resume cycle for 16GB RAM out of 32GB in use takes
around 21 minutes before the change, and 1 minutes after the change on
a system with limited storage IOPS.

Signed-off-by: Xiaoyi Chen <cxiaoyi@amazon.com>
Co-Developed-by: Anchal Agarwal <anchalag@amazon.com>
Signed-off-by: Anchal Agarwal <anchalag@amazon.com>
[ rjw: Subject and changelog edits, white space damage fixes ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-09-28 15:58:18 +02:00
Christoph Hellwig
36daaa98f7 PM: mm: cleanup swsusp_swap_check
Use blkdev_get_by_dev instead of bdget + blkdev_get.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-09-23 10:43:19 -06:00
Christoph Hellwig
21bd900572 mm: split swap_type_of
swap_type_of is used for two entirely different purposes:

 (1) check what swap type a given device/offset corresponds to
 (2) find the first available swap device that can be written to

Mixing both in a single function creates an unreadable mess.  Create two
separate functions instead, and switch both to pass a dev_t instead of
a struct block_device to further simplify the code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-09-23 10:43:19 -06:00