lk/linux-kernel-test
1
0
Fork 0
Code Issues Pull Requests 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

13
Documentation/power/interface.txt
View File

@@ -30,6 +30,17 @@ testing). The system will support either 'firmware' or 'platform', and
that is known a priori. But, the user may choose 'shutdown' or
'reboot' as alternatives.
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.
Reading from this file will display what the mode is currently set
to. Writing to this file will accept one of
@@ -37,6 +48,8 @@ to. Writing to this file will accept one of
'platform'
'shutdown'
'reboot'
'testproc'
'test'
It will only change to 'firmware' or 'platform' if the system supports
it.