Commit 90dda1cb authored by Johannes Berg's avatar Johannes Berg Committed by Len Brown
Browse files

PM: Make PM_TRACE more architecture independent 



When trying to debug a suspend failure I started implementing
PM_TRACE for powerpc. I then noticed that I'm debugging a suspend
failure and so PM_TRACE isn't useful at all, but thought that
nonetheless this could be useful in the future.

Basically, to support PM_TRACE, you add a Kconfig option that
selects PM_TRACE and provides the infrastructure as per the
help text of PM_TRACE.

Signed-off-by: default avatarJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: default avatarRafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: default avatarLen Brown <len.brown@intel.com>
parent ce2b7147

drivers/base/power/Makefile

+1 −1
Original line number Diff line number Diff line 
obj-$(CONFIG_PM)	+= sysfs.o

obj-$(CONFIG_PM_SLEEP)	+= main.o

obj-$(CONFIG_PM_TRACE)	+= trace.o

obj-$(CONFIG_PM_TRACE_RTC)	+= trace.o



ccflags-$(CONFIG_DEBUG_DRIVER) := -DDEBUG

ccflags-$(CONFIG_PM_VERBOSE)   += -DDEBUG

kernel/power/Kconfig

+22 −1
Original line number Diff line number Diff line
@@ -44,9 +44,30 @@ config PM_VERBOSE 
	---help---

	This option enables verbose messages from the Power Management code.



config CAN_PM_TRACE

	def_bool y

	depends on PM_DEBUG && PM_SLEEP && EXPERIMENTAL



config PM_TRACE

	bool

	help

	  This enables code to save the last PM event point across

	  reboot. The architecture needs to support this, x86 for

	  example does by saving things in the RTC, see below.



	  The architecture specific code must provide the extern

	  functions from <linux/resume-trace.h> as well as the

	  <asm/resume-trace.h> header with a TRACE_RESUME() macro.



	  The way the information is presented is architecture-

	  dependent, x86 will print the information during a

	  late_initcall.



config PM_TRACE_RTC

	bool "Suspend/resume event tracing"

	depends on PM_DEBUG && X86 && PM_SLEEP && EXPERIMENTAL

	depends on CAN_PM_TRACE

	depends on X86

	select PM_TRACE

	default n

	---help---

	This enables some cheesy code to save the last PM event point in the

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