From abf917cd91cbb73952758f9741e2fa65002a48ee Mon Sep 17 00:00:00 2001 From: Frederic Weisbecker Date: Wed, 25 Jul 2012 07:56:04 +0200 Subject: cputime: Generic on-demand virtual cputime accounting If we want to stop the tick further idle, we need to be able to account the cputime without using the tick. Virtual based cputime accounting solves that problem by hooking into kernel/user boundaries. However implementing CONFIG_VIRT_CPU_ACCOUNTING require low level hooks and involves more overhead. But we already have a generic context tracking subsystem that is required for RCU needs by archs which plan to shut down the tick outside idle. This patch implements a generic virtual based cputime accounting that relies on these generic kernel/user hooks. There are some upsides of doing this: - This requires no arch code to implement CONFIG_VIRT_CPU_ACCOUNTING if context tracking is already built (already necessary for RCU in full tickless mode). - We can rely on the generic context tracking subsystem to dynamically (de)activate the hooks, so that we can switch anytime between virtual and tick based accounting. This way we don't have the overhead of the virtual accounting when the tick is running periodically. And one downside: - There is probably more overhead than a native virtual based cputime accounting. But this relies on hooks that are already set anyway. Signed-off-by: Frederic Weisbecker Cc: Andrew Morton Cc: Ingo Molnar Cc: Li Zhong Cc: Namhyung Kim Cc: Paul E. McKenney Cc: Paul Gortmaker Cc: Peter Zijlstra Cc: Steven Rostedt Cc: Thomas Gleixner --- arch/powerpc/configs/chroma_defconfig | 2 +- arch/powerpc/configs/corenet64_smp_defconfig | 2 +- arch/powerpc/configs/pasemi_defconfig | 2 +- arch/powerpc/include/asm/cputime.h | 6 +++--- arch/powerpc/include/asm/lppaca.h | 2 +- arch/powerpc/include/asm/ppc_asm.h | 4 ++-- arch/powerpc/kernel/entry_64.S | 4 ++-- arch/powerpc/kernel/time.c | 4 ++-- arch/powerpc/platforms/pseries/dtl.c | 6 +++--- arch/powerpc/platforms/pseries/setup.c | 6 +++--- 10 files changed, 19 insertions(+), 19 deletions(-) (limited to 'arch/powerpc') diff --git a/arch/powerpc/configs/chroma_defconfig b/arch/powerpc/configs/chroma_defconfig index 29bb11ec6c64..4f35fc462385 100644 --- a/arch/powerpc/configs/chroma_defconfig +++ b/arch/powerpc/configs/chroma_defconfig @@ -1,6 +1,6 @@ CONFIG_PPC64=y CONFIG_PPC_BOOK3E_64=y -# CONFIG_VIRT_CPU_ACCOUNTING is not set +# CONFIG_VIRT_CPU_ACCOUNTING_NATIVE is not set CONFIG_SMP=y CONFIG_NR_CPUS=256 CONFIG_EXPERIMENTAL=y diff --git a/arch/powerpc/configs/corenet64_smp_defconfig b/arch/powerpc/configs/corenet64_smp_defconfig index 88fa5c46f66f..f7df8362911f 100644 --- a/arch/powerpc/configs/corenet64_smp_defconfig +++ b/arch/powerpc/configs/corenet64_smp_defconfig @@ -1,6 +1,6 @@ CONFIG_PPC64=y CONFIG_PPC_BOOK3E_64=y -# CONFIG_VIRT_CPU_ACCOUNTING is not set +# CONFIG_VIRT_CPU_ACCOUNTING_NATIVE is not set CONFIG_SMP=y CONFIG_NR_CPUS=2 CONFIG_EXPERIMENTAL=y diff --git a/arch/powerpc/configs/pasemi_defconfig b/arch/powerpc/configs/pasemi_defconfig index 840a2c2d0430..bcedeea0df89 100644 --- a/arch/powerpc/configs/pasemi_defconfig +++ b/arch/powerpc/configs/pasemi_defconfig @@ -1,6 +1,6 @@ CONFIG_PPC64=y CONFIG_ALTIVEC=y -# CONFIG_VIRT_CPU_ACCOUNTING is not set +# CONFIG_VIRT_CPU_ACCOUNTING_NATIVE is not set CONFIG_SMP=y CONFIG_NR_CPUS=2 CONFIG_EXPERIMENTAL=y diff --git a/arch/powerpc/include/asm/cputime.h b/arch/powerpc/include/asm/cputime.h index 483733bd06d4..607559ab271f 100644 --- a/arch/powerpc/include/asm/cputime.h +++ b/arch/powerpc/include/asm/cputime.h @@ -8,7 +8,7 @@ * as published by the Free Software Foundation; either version * 2 of the License, or (at your option) any later version. * - * If we have CONFIG_VIRT_CPU_ACCOUNTING, we measure cpu time in + * If we have CONFIG_VIRT_CPU_ACCOUNTING_NATIVE, we measure cpu time in * the same units as the timebase. Otherwise we measure cpu time * in jiffies using the generic definitions. */ @@ -16,7 +16,7 @@ #ifndef __POWERPC_CPUTIME_H #define __POWERPC_CPUTIME_H -#ifndef CONFIG_VIRT_CPU_ACCOUNTING +#ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE #include #ifdef __KERNEL__ static inline void setup_cputime_one_jiffy(void) { } @@ -231,5 +231,5 @@ static inline cputime_t clock_t_to_cputime(const unsigned long clk) static inline void arch_vtime_task_switch(struct task_struct *tsk) { } #endif /* __KERNEL__ */ -#endif /* CONFIG_VIRT_CPU_ACCOUNTING */ +#endif /* CONFIG_VIRT_CPU_ACCOUNTING_NATIVE */ #endif /* __POWERPC_CPUTIME_H */ diff --git a/arch/powerpc/include/asm/lppaca.h b/arch/powerpc/include/asm/lppaca.h index 531fe0c3108f..b1e7f2af1016 100644 --- a/arch/powerpc/include/asm/lppaca.h +++ b/arch/powerpc/include/asm/lppaca.h @@ -145,7 +145,7 @@ struct dtl_entry { extern struct kmem_cache *dtl_cache; /* - * When CONFIG_VIRT_CPU_ACCOUNTING = y, the cpu accounting code controls + * When CONFIG_VIRT_CPU_ACCOUNTING_NATIVE = y, the cpu accounting code controls * reading from the dispatch trace log. If other code wants to consume * DTL entries, it can set this pointer to a function that will get * called once for each DTL entry that gets processed. diff --git a/arch/powerpc/include/asm/ppc_asm.h b/arch/powerpc/include/asm/ppc_asm.h index ea2a86e8ff95..2d0e1f5d8339 100644 --- a/arch/powerpc/include/asm/ppc_asm.h +++ b/arch/powerpc/include/asm/ppc_asm.h @@ -24,7 +24,7 @@ * user_time and system_time fields in the paca. */ -#ifndef CONFIG_VIRT_CPU_ACCOUNTING +#ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE #define ACCOUNT_CPU_USER_ENTRY(ra, rb) #define ACCOUNT_CPU_USER_EXIT(ra, rb) #define ACCOUNT_STOLEN_TIME @@ -70,7 +70,7 @@ END_FW_FTR_SECTION_IFSET(FW_FEATURE_SPLPAR) #endif /* CONFIG_PPC_SPLPAR */ -#endif /* CONFIG_VIRT_CPU_ACCOUNTING */ +#endif /* CONFIG_VIRT_CPU_ACCOUNTING_NATIVE */ /* * Macros for storing registers into and loading registers from diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S index b310a0573625..a0ca42fb1541 100644 --- a/arch/powerpc/kernel/entry_64.S +++ b/arch/powerpc/kernel/entry_64.S @@ -94,7 +94,7 @@ system_call_common: addi r9,r1,STACK_FRAME_OVERHEAD ld r11,exception_marker@toc(r2) std r11,-16(r9) /* "regshere" marker */ -#if defined(CONFIG_VIRT_CPU_ACCOUNTING) && defined(CONFIG_PPC_SPLPAR) +#if defined(CONFIG_VIRT_CPU_ACCOUNTING_NATIVE) && defined(CONFIG_PPC_SPLPAR) BEGIN_FW_FTR_SECTION beq 33f /* if from user, see if there are any DTL entries to process */ @@ -110,7 +110,7 @@ BEGIN_FW_FTR_SECTION addi r9,r1,STACK_FRAME_OVERHEAD 33: END_FW_FTR_SECTION_IFSET(FW_FEATURE_SPLPAR) -#endif /* CONFIG_VIRT_CPU_ACCOUNTING && CONFIG_PPC_SPLPAR */ +#endif /* CONFIG_VIRT_CPU_ACCOUNTING_NATIVE && CONFIG_PPC_SPLPAR */ /* * A syscall should always be called with interrupts enabled diff --git a/arch/powerpc/kernel/time.c b/arch/powerpc/kernel/time.c index 6f6b1cccc916..22c9b67f9983 100644 --- a/arch/powerpc/kernel/time.c +++ b/arch/powerpc/kernel/time.c @@ -143,7 +143,7 @@ EXPORT_SYMBOL_GPL(ppc_proc_freq); unsigned long ppc_tb_freq; EXPORT_SYMBOL_GPL(ppc_tb_freq); -#ifdef CONFIG_VIRT_CPU_ACCOUNTING +#ifdef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE /* * Factors for converting from cputime_t (timebase ticks) to * jiffies, microseconds, seconds, and clock_t (1/USER_HZ seconds). @@ -377,7 +377,7 @@ void vtime_account_user(struct task_struct *tsk) account_user_time(tsk, utime, utimescaled); } -#else /* ! CONFIG_VIRT_CPU_ACCOUNTING */ +#else /* ! CONFIG_VIRT_CPU_ACCOUNTING_NATIVE */ #define calc_cputime_factors() #endif diff --git a/arch/powerpc/platforms/pseries/dtl.c b/arch/powerpc/platforms/pseries/dtl.c index a7648543c59e..0cc0ac07a55d 100644 --- a/arch/powerpc/platforms/pseries/dtl.c +++ b/arch/powerpc/platforms/pseries/dtl.c @@ -57,7 +57,7 @@ static u8 dtl_event_mask = 0x7; */ static int dtl_buf_entries = N_DISPATCH_LOG; -#ifdef CONFIG_VIRT_CPU_ACCOUNTING +#ifdef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE struct dtl_ring { u64 write_index; struct dtl_entry *write_ptr; @@ -142,7 +142,7 @@ static u64 dtl_current_index(struct dtl *dtl) return per_cpu(dtl_rings, dtl->cpu).write_index; } -#else /* CONFIG_VIRT_CPU_ACCOUNTING */ +#else /* CONFIG_VIRT_CPU_ACCOUNTING_NATIVE */ static int dtl_start(struct dtl *dtl) { @@ -188,7 +188,7 @@ static u64 dtl_current_index(struct dtl *dtl) { return lppaca_of(dtl->cpu).dtl_idx; } -#endif /* CONFIG_VIRT_CPU_ACCOUNTING */ +#endif /* CONFIG_VIRT_CPU_ACCOUNTING_NATIVE */ static int dtl_enable(struct dtl *dtl) { diff --git a/arch/powerpc/platforms/pseries/setup.c b/arch/powerpc/platforms/pseries/setup.c index ca55882465d6..527e12c9573b 100644 --- a/arch/powerpc/platforms/pseries/setup.c +++ b/arch/powerpc/platforms/pseries/setup.c @@ -281,7 +281,7 @@ static struct notifier_block pci_dn_reconfig_nb = { struct kmem_cache *dtl_cache; -#ifdef CONFIG_VIRT_CPU_ACCOUNTING +#ifdef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE /* * Allocate space for the dispatch trace log for all possible cpus * and register the buffers with the hypervisor. This is used for @@ -332,12 +332,12 @@ static int alloc_dispatch_logs(void) return 0; } -#else /* !CONFIG_VIRT_CPU_ACCOUNTING */ +#else /* !CONFIG_VIRT_CPU_ACCOUNTING_NATIVE */ static inline int alloc_dispatch_logs(void) { return 0; } -#endif /* CONFIG_VIRT_CPU_ACCOUNTING */ +#endif /* CONFIG_VIRT_CPU_ACCOUNTING_NATIVE */ static int alloc_dispatch_log_kmem_cache(void) { -- cgit v1.2.1 From c11f11fcbdb5be790c565aed46411486a7586afc Mon Sep 17 00:00:00 2001 From: Frederic Weisbecker Date: Mon, 21 Jan 2013 00:50:22 +0100 Subject: kvm: Prepare to add generic guest entry/exit callbacks Do some ground preparatory work before adding guest_enter() and guest_exit() context tracking callbacks. Those will be later used to read the guest cputime safely when we run in full dynticks mode. Signed-off-by: Frederic Weisbecker Cc: Andrew Morton Cc: Gleb Natapov Cc: Ingo Molnar Cc: Li Zhong Cc: Marcelo Tosatti Cc: Namhyung Kim Cc: Paul E. McKenney Cc: Paul Gortmaker Cc: Peter Zijlstra Cc: Steven Rostedt Cc: Thomas Gleixner --- arch/powerpc/kernel/time.c | 1 + 1 file changed, 1 insertion(+) (limited to 'arch/powerpc') diff --git a/arch/powerpc/kernel/time.c b/arch/powerpc/kernel/time.c index 22c9b67f9983..2e04b37f67f9 100644 --- a/arch/powerpc/kernel/time.c +++ b/arch/powerpc/kernel/time.c @@ -347,6 +347,7 @@ void vtime_account_system(struct task_struct *tsk) if (stolen) account_steal_time(stolen); } +EXPORT_SYMBOL_GPL(vtime_account_system); void vtime_account_idle(struct task_struct *tsk) { -- cgit v1.2.1 From 993db4b45fd99949d8f6e004a7744b523dca473a Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Mon, 11 Feb 2013 10:45:33 +0100 Subject: sched, powerpc: Fix sched.h split-up build failure Fix PowerPC/Cell build fallout from: 8bd75c77b7c6 sched/rt: Move rt specific bits into new header file Reported-by: Michael Ellerman Cc: Clark Williams Cc: Peter Zijlstra Cc: Steven Rostedt Link: http://lkml.kernel.org/r/20130207094707.7b9f825f@riff.lan Signed-off-by: Ingo Molnar --- arch/powerpc/platforms/cell/spufs/sched.c | 1 + 1 file changed, 1 insertion(+) (limited to 'arch/powerpc') diff --git a/arch/powerpc/platforms/cell/spufs/sched.c b/arch/powerpc/platforms/cell/spufs/sched.c index 25db92a8e1cf..49318385d4fa 100644 --- a/arch/powerpc/platforms/cell/spufs/sched.c +++ b/arch/powerpc/platforms/cell/spufs/sched.c @@ -24,6 +24,7 @@ #include #include +#include #include #include #include -- cgit v1.2.1