| Message ID | 1376768819-28975-4-git-send-email-toshi.kani@hp.com (mailing list archive) |
|---|---|
| State | Not Applicable |
| Headers | show |
On Saturday, August 17, 2013 01:46:58 PM Toshi Kani wrote: > Commit d7c53c9e enabled ARCH_CPU_PROBE_RELEASE on x86 in order to > serialize CPU online/offline operations. Although it is the config > option to enable CPU hotplug test interfaces, probe & release, it is > also the option to enable cpu_hotplug_driver_lock() as well. Therefore, > this option had to be enabled on x86 with dummy arch_cpu_probe() and > arch_cpu_release(). > > Since then, lock_device_hotplug() was introduced to serialize CPU > online/offline & hotplug operations. Therefore, this config option > is no longer required for the serialization. This patch disables > this config option on x86 and revert the changes made by commit > d7c53c9e. > > Signed-off-by: Toshi Kani <toshi.kani@hp.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> > --- > arch/x86/Kconfig | 4 ---- > arch/x86/kernel/smpboot.c | 21 --------------------- > 2 files changed, 25 deletions(-) > > diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig > index b32ebf9..c87e49a 100644 > --- a/arch/x86/Kconfig > +++ b/arch/x86/Kconfig > @@ -255,10 +255,6 @@ config ARCH_HWEIGHT_CFLAGS > default "-fcall-saved-ecx -fcall-saved-edx" if X86_32 > default "-fcall-saved-rdi -fcall-saved-rsi -fcall-saved-rdx -fcall-saved-rcx -fcall-saved-r8 -fcall-saved-r9 -fcall-saved-r10 -fcall-saved-r11" if X86_64 > > -config ARCH_CPU_PROBE_RELEASE > - def_bool y > - depends on HOTPLUG_CPU > - > config ARCH_SUPPORTS_UPROBES > def_bool y > > diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c > index aecc98a..5b24a9d 100644 > --- a/arch/x86/kernel/smpboot.c > +++ b/arch/x86/kernel/smpboot.c > @@ -82,27 +82,6 @@ > /* State of each CPU */ > DEFINE_PER_CPU(int, cpu_state) = { 0 }; > > -#ifdef CONFIG_HOTPLUG_CPU > -/* > - * We need this for trampoline_base protection from concurrent accesses when > - * off- and onlining cores wildly. > - */ > -static DEFINE_MUTEX(x86_cpu_hotplug_driver_mutex); > - > -void cpu_hotplug_driver_lock(void) > -{ > - mutex_lock(&x86_cpu_hotplug_driver_mutex); > -} > - > -void cpu_hotplug_driver_unlock(void) > -{ > - mutex_unlock(&x86_cpu_hotplug_driver_mutex); > -} > - > -ssize_t arch_cpu_probe(const char *buf, size_t count) { return -1; } > -ssize_t arch_cpu_release(const char *buf, size_t count) { return -1; } > -#endif > - > /* Number of siblings per CPU package */ > int smp_num_siblings = 1; > EXPORT_SYMBOL(smp_num_siblings); > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index b32ebf9..c87e49a 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -255,10 +255,6 @@ config ARCH_HWEIGHT_CFLAGS default "-fcall-saved-ecx -fcall-saved-edx" if X86_32 default "-fcall-saved-rdi -fcall-saved-rsi -fcall-saved-rdx -fcall-saved-rcx -fcall-saved-r8 -fcall-saved-r9 -fcall-saved-r10 -fcall-saved-r11" if X86_64 -config ARCH_CPU_PROBE_RELEASE - def_bool y - depends on HOTPLUG_CPU - config ARCH_SUPPORTS_UPROBES def_bool y diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c index aecc98a..5b24a9d 100644 --- a/arch/x86/kernel/smpboot.c +++ b/arch/x86/kernel/smpboot.c @@ -82,27 +82,6 @@ /* State of each CPU */ DEFINE_PER_CPU(int, cpu_state) = { 0 }; -#ifdef CONFIG_HOTPLUG_CPU -/* - * We need this for trampoline_base protection from concurrent accesses when - * off- and onlining cores wildly. - */ -static DEFINE_MUTEX(x86_cpu_hotplug_driver_mutex); - -void cpu_hotplug_driver_lock(void) -{ - mutex_lock(&x86_cpu_hotplug_driver_mutex); -} - -void cpu_hotplug_driver_unlock(void) -{ - mutex_unlock(&x86_cpu_hotplug_driver_mutex); -} - -ssize_t arch_cpu_probe(const char *buf, size_t count) { return -1; } -ssize_t arch_cpu_release(const char *buf, size_t count) { return -1; } -#endif - /* Number of siblings per CPU package */ int smp_num_siblings = 1; EXPORT_SYMBOL(smp_num_siblings);
Commit d7c53c9e enabled ARCH_CPU_PROBE_RELEASE on x86 in order to serialize CPU online/offline operations. Although it is the config option to enable CPU hotplug test interfaces, probe & release, it is also the option to enable cpu_hotplug_driver_lock() as well. Therefore, this option had to be enabled on x86 with dummy arch_cpu_probe() and arch_cpu_release(). Since then, lock_device_hotplug() was introduced to serialize CPU online/offline & hotplug operations. Therefore, this config option is no longer required for the serialization. This patch disables this config option on x86 and revert the changes made by commit d7c53c9e. Signed-off-by: Toshi Kani <toshi.kani@hp.com> --- arch/x86/Kconfig | 4 ---- arch/x86/kernel/smpboot.c | 21 --------------------- 2 files changed, 25 deletions(-)