kernel_optimize_test/kernel/power
Johannes Berg fe0c935a6c rework pm_ops pm_disk_mode, kill misuse
This patch series cleans up some misconceptions about pm_ops.  Some users of
the pm_ops structure attempt to use it to stop the user from entering suspend
to disk, this, however, is not possible since the user can always use
"shutdown" in /sys/power/disk and then the pm_ops are never invoked.  Also,
platforms that don't support suspend to disk simply should not allow
configuring SOFTWARE_SUSPEND (read the help text on it, it only selects
suspend to disk and nothing else, all the other stuff depends on PM).

The pm_ops structure is actually intended to provide a way to enter
platform-defined sleep states (currently supported states are "standby" and
"mem" (suspend to ram)) and additionally (if SOFTWARE_SUSPEND is configured)
allows a platform to support a platform specific way to enter low-power mode
once everything has been saved to disk.  This is currently only used by ACPI
(S4).

This patch:

The pm_ops.pm_disk_mode is used in totally bogus ways since nobody really
seems to understand what it actually does.

This patch clarifies the pm_disk_mode description.

It also removes all the arm and sh users that think they can veto suspend to
disk via pm_ops; not so since the user can always do echo shutdown >
/sys/power/disk, they need to find a better way involving Kconfig or such.

ACPI is the only user left with a non-zero pm_disk_mode.

The patch also sets the default mode to shutdown again, but when a new pm_ops
is registered its pm_disk_mode is selected as default, that way the default
stays for ACPI where it is apparently required.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Cc: David Brownell <david-b@pacbell.net>
Acked-by: Pavel Machek <pavel@ucw.cz>
Cc: <linux-pm@lists.linux-foundation.org>
Cc: Len Brown <lenb@kernel.org>
Acked-by: Russell King <rmk@arm.linux.org.uk>
Cc: Greg KH <greg@kroah.com>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-04-30 16:40:40 -07:00
..
console.c [PATCH] swsusp: fix suspend when console is in VT_AUTO+KD_GRAPHICS mode 2007-03-16 19:25:05 -07:00
disk.c rework pm_ops pm_disk_mode, kill misuse 2007-04-30 16:40:40 -07:00
Kconfig [PATCH] kconfig: Update swsusp description 2007-03-06 09:30:26 -08:00
main.c rework pm_ops pm_disk_mode, kill misuse 2007-04-30 16:40:40 -07:00
Makefile [PATCH] Disable CPU hotplug during suspend 2006-09-26 08:48:59 -07:00
pm.c [PATCH] remove kernel/power/pm.c:pm_unregister_all() 2006-07-12 16:09:08 -07:00
power.h [PATCH] convert pm_sem to a mutex 2006-12-07 08:39:28 -08:00
poweroff.c WorkStruct: Pass the work_struct pointer instead of context data 2006-11-22 14:55:48 +00:00
process.c [PATCH] PM: Fix SMP races in the freezer 2006-12-13 09:05:49 -08:00
snapshot.c [PATCH] Use ZVC for free_pages 2007-02-11 10:51:17 -08:00
swap.c [PATCH] swsusp: Do not fail if resume device is not set 2007-01-05 23:55:22 -08:00
swsusp.c [PATCH] swsusp: fix memory shrinker 2007-04-04 21:12:47 -07:00
user.c [PATCH] Revert "swsusp: disable nonboot CPUs before entering platform suspend" 2007-03-27 09:20:03 -07:00