[PATCH] PM: Fix dependencies of CONFIG_SUSPEND and CONFIG_HIBERNATION (updated 3x)

["Rafael J. Wysocki" <rjw@sisk.pl>]

On Thursday, 9 August 2007 00:03, Andrew Morton wrote:
> On Tue, 7 Aug 2007 00:23:26 +0200
> "Rafael J. Wysocki" <rjw@sisk.pl> wrote:
> 
> > Dependencies of CONFIG_SUSPEND and CONFIG_HIBERNATION introduced by commit
> > 296699de6bdc717189a331ab6bbe90e05c94db06 "Introduce CONFIG_SUSPEND for
> > suspend-to-Ram and standby" are incorrect, as they don't cover the facts that
> > (1) not all architectures support suspend and (2) SMP hibernation is only
> > possible on X86 and PPC64 (if CONFIG_PPC64_SWSUSP is set).
> > 
> > Moreover, SMP suspend and hibernation are only possible if CONFIG_HOTPLUG is
> > set, because they select HOTPLUG_CPU that depends on it. __Also, since suspend
> > and hibernation don't depend on EXPERIMENTAL, arrange things so that CPU
> > hotplug can be selected if it is not set.
> 
> The version of this which I have (version eighty eight, afaict :),
> reproduced below) breaks ia64 allmodconfig:
> 
> init/Kconfig:416:error: found recursive dependency: HOTPLUG -> SUSPEND_SMP_POSSIBLE -> PM_SLEEP_SMP -> HOTPLUG_CPU -> HOTPLUG
>  -> PCCARD -> PCMCIA -> USB_ARCH_HAS_HCD -> MOUSE_APPLETOUCH -> USB -> USB_SISUS

OK

Here's the minimal version of the patch, without the tricky dependencies on
HOTPLUG and PM_SLEEP_SMP.

I have tested allmodconfig (cross) compilation of it for ia64 and powerpc
(ppc32).  It also has been tested on x86_64 and i386 as well as (cross)
compiled for some ARM platforms.  Hope that's enough (fingers crossed).

---
From: Rafael J. Wysocki <rjw@sisk.pl>

Dependencies of CONFIG_SUSPEND and CONFIG_HIBERNATION introduced by commit
296699de6bdc717189a331ab6bbe90e05c94db06 "Introduce CONFIG_SUSPEND for
suspend-to-Ram and standby" are incorrect, as they don't cover the facts that
(1) not all architectures support suspend and (2) SMP hibernation is only
possible on X86 and PPC64 (if CONFIG_PPC64_SWSUSP is set).

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
---
 arch/x86_64/defconfig |    1 -
 include/linux/cpu.h   |    6 +++---
 kernel/cpu.c          |    4 ++--
 kernel/power/Kconfig  |   41 +++++++++++++++++++++++++++++++----------
 4 files changed, 36 insertions(+), 16 deletions(-)

Index: linux-2.6.23-rc2/kernel/power/Kconfig
===================================================================
--- linux-2.6.23-rc2.orig/kernel/power/Kconfig
+++ linux-2.6.23-rc2/kernel/power/Kconfig
@@ -72,15 +72,10 @@ config PM_TRACE
 	CAUTION: this option will cause your machine's real-time clock to be
 	set to an invalid time after a resume.
 
-config SUSPEND_SMP_POSSIBLE
-	bool
-	depends on (X86 && !X86_VOYAGER) || (PPC64 && (PPC_PSERIES || PPC_PMAC))
-	depends on SMP
-	default y
-
-config SUSPEND_SMP
+config PM_SLEEP_SMP
 	bool
-	depends on SUSPEND_SMP_POSSIBLE && PM_SLEEP
+	depends on SUSPEND_SMP_POSSIBLE || HIBERNATION_SMP_POSSIBLE
+	depends on PM_SLEEP
 	select HOTPLUG_CPU
 	default y
 
@@ -89,20 +84,46 @@ config PM_SLEEP
 	depends on SUSPEND || HIBERNATION
 	default y
 
+config SUSPEND_UP_POSSIBLE
+	bool
+	depends on (X86 && !X86_VOYAGER) || PPC || ARM || BLACKFIN || MIPS \
+		   || SUPERH || FRV
+	depends on !SMP
+	default y
+
+config SUSPEND_SMP_POSSIBLE
+	bool
+	depends on (X86 && !X86_VOYAGER) \
+		   || (PPC && (PPC_PSERIES || PPC_PMAC)) || ARM
+	depends on SMP
+	default y
+
 config SUSPEND
 	bool "Suspend to RAM and standby"
 	depends on PM
-	depends on !SMP || SUSPEND_SMP_POSSIBLE
+	depends on SUSPEND_UP_POSSIBLE || SUSPEND_SMP_POSSIBLE
 	default y
 	---help---
 	  Allow the system to enter sleep states in which main memory is
 	  powered and thus its contents are preserved, such as the
 	  suspend-to-RAM state (i.e. the ACPI S3 state).
 
+config HIBERNATION_UP_POSSIBLE
+	bool
+	depends on X86 || PPC64_SWSUSP || FRV || PPC32
+	depends on !SMP
+	default y
+
+config HIBERNATION_SMP_POSSIBLE
+	bool
+	depends on (X86 && !X86_VOYAGER) || PPC64_SWSUSP
+	depends on SMP
+	default y
+
 config HIBERNATION
 	bool "Hibernation (aka 'suspend to disk')"
 	depends on PM && SWAP
-	depends on ((X86 || PPC64_SWSUSP || FRV || PPC32) && !SMP) || SUSPEND_SMP_POSSIBLE
+	depends on HIBERNATION_UP_POSSIBLE || HIBERNATION_SMP_POSSIBLE
 	---help---
 	  Enable the suspend to disk (STD) functionality, which is usually
 	  called "hibernation" in user interfaces.  STD checkpoints the
Index: linux-2.6.23-rc2/kernel/cpu.c
===================================================================
--- linux-2.6.23-rc2.orig/kernel/cpu.c
+++ linux-2.6.23-rc2/kernel/cpu.c
@@ -273,7 +273,7 @@ int __cpuinit cpu_up(unsigned int cpu)
 	return err;
 }
 
-#ifdef CONFIG_SUSPEND_SMP
+#ifdef CONFIG_PM_SLEEP_SMP
 static cpumask_t frozen_cpus;
 
 int disable_nonboot_cpus(void)
@@ -334,4 +334,4 @@ void enable_nonboot_cpus(void)
 out:
 	mutex_unlock(&cpu_add_remove_lock);
 }
-#endif
+#endif /* CONFIG_PM_SLEEP_SMP */
Index: linux-2.6.23-rc2/include/linux/cpu.h
===================================================================
--- linux-2.6.23-rc2.orig/include/linux/cpu.h
+++ linux-2.6.23-rc2/include/linux/cpu.h
@@ -128,16 +128,16 @@ static inline void cpuhotplug_mutex_unlo
 static inline int cpu_is_offline(int cpu) { return 0; }
 #endif		/* CONFIG_HOTPLUG_CPU */
 
-#ifdef CONFIG_SUSPEND_SMP
+#ifdef CONFIG_PM_SLEEP_SMP
 extern int suspend_cpu_hotplug;
 
 extern int disable_nonboot_cpus(void);
 extern void enable_nonboot_cpus(void);
-#else
+#else /* !CONFIG_PM_SLEEP_SMP */
 #define suspend_cpu_hotplug	0
 
 static inline int disable_nonboot_cpus(void) { return 0; }
 static inline void enable_nonboot_cpus(void) {}
-#endif
+#endif /* !CONFIG_PM_SLEEP_SMP */
 
 #endif /* _LINUX_CPU_H_ */
Index: linux-2.6.23-rc2/arch/x86_64/defconfig
===================================================================
--- linux-2.6.23-rc2.orig/arch/x86_64/defconfig
+++ linux-2.6.23-rc2/arch/x86_64/defconfig
@@ -201,7 +201,6 @@ CONFIG_PM=y
 # CONFIG_PM_DEBUG is not set
 CONFIG_HIBERNATION=y
 CONFIG_PM_STD_PARTITION=""
-CONFIG_SUSPEND_SMP=y
 
 #
 # ACPI (Advanced Configuration and Power Interface) Support