xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

[PATCH] swsusp: debugging

Browse Source 
Add a swsusp debugging mode.  This does everything that's needed for a suspend
except for actually suspending.  So we can look in the log messages and work
out a) what code is being slow and b) which drivers are misbehaving.

(1)
# echo testproc > /sys/power/disk
# echo disk > /sys/power/state

This should turn off the non-boot CPU, freeze all processes, wait for 5
seconds and then thaw the processes and the CPU.

(2)
# echo test > /sys/power/disk
# echo disk > /sys/power/state

This should turn off the non-boot CPU, freeze all processes, shrink
memory, suspend all devices, wait for 5 seconds, resume the devices etc.

Cc: Pavel Machek <pavel@ucw.cz>
Cc: Stefan Seyfried <seife@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Rafael J. Wysocki
2006-11-02 22:07:19 -08:00
committed by Linus Torvalds
parent 90d5390944
commit b918f6e62c
4 changed files with 60 additions and 11 deletions
Download Patch File Download Diff File Expand all files Collapse all files

17
Documentation/ABI/testing/sysfs-power
View File

@@ -21,7 +21,7 @@ Description:
these states.
What: /sys/power/disk
Date: August 2006
Date: September 2006
Contact: Rafael J. Wysocki <rjw@sisk.pl>
Description:
The /sys/power/disk file controls the operating mode of the
@@ -39,6 +39,19 @@ Description:
'reboot' - the memory image will be saved by the kernel and
the system will be rebooted.
Additionally, /sys/power/disk can be used to turn on one of the
two testing modes of the suspend-to-disk mechanism: 'testproc'
or 'test'. If the suspend-to-disk mechanism is in the
'testproc' mode, writing 'disk' to /sys/power/state will cause
the kernel to disable nonboot CPUs and freeze tasks, wait for 5
seconds, unfreeze tasks and enable nonboot CPUs. If it is in
the 'test' mode, writing 'disk' to /sys/power/state will cause
the kernel to disable nonboot CPUs and freeze tasks, shrink
memory, suspend devices, wait for 5 seconds, resume devices,
unfreeze tasks and enable nonboot CPUs. Then, we are able to
look in the log messages and work out, for example, which code
is being slow and which device drivers are misbehaving.
The suspend-to-disk method may be chosen by writing to this
file one of the accepted strings:
@@ -46,6 +59,8 @@ Description:
'platform'
'shutdown'
'reboot'
'testproc'
'test'
It will only change to 'firmware' or 'platform' if the system
supports that.