[PATCH -mm 3/3] swsusp: Document testing code

From: Rafael J. Wysocki
Date: Thu Sep 28 2006 - 18:20:05 EST


Update the swsusp documentation to cover the recently introduced testing
code.

Signed-off-by: Rafael J. Wysocki <rjw@xxxxxxx>
---
Documentation/ABI/testing/sysfs-power | 17 ++++++++++++++++-
Documentation/power/interface.txt | 13 +++++++++++++
2 files changed, 29 insertions(+), 1 deletion(-)

Index: linux-2.6.18-mm2/Documentation/ABI/testing/sysfs-power
===================================================================
--- linux-2.6.18-mm2.orig/Documentation/ABI/testing/sysfs-power 2006-09-28 21:53:01.000000000 +0200
+++ linux-2.6.18-mm2/Documentation/ABI/testing/sysfs-power 2006-09-28 23:37:50.000000000 +0200
@@ -21,7 +21,7 @@ Description:
these states.

What: /sys/power/disk
-Date: August 2006
+Date: September 2006
Contact: Rafael J. Wysocki <rjw@xxxxxxx>
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.
Index: linux-2.6.18-mm2/Documentation/power/interface.txt
===================================================================
--- linux-2.6.18-mm2.orig/Documentation/power/interface.txt 2006-09-28 21:53:01.000000000 +0200
+++ linux-2.6.18-mm2/Documentation/power/interface.txt 2006-09-28 23:34:39.000000000 +0200
@@ -30,6 +30,17 @@ testing). The system will support either
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
'platform'
'shutdown'
'reboot'
+ 'testproc'
+ 'test'

It will only change to 'firmware' or 'platform' if the system supports
it.
-
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