From 39613766e8826756a4bf8c74274eb971c3c1d929 Mon Sep 17 00:00:00 2001 From: Frederic Weisbecker Date: Tue, 15 Jan 2013 13:25:07 +0100 Subject: cputime: Librarize per nsecs resolution cputime definitions The full dynticks cputime accounting that we'll soon introduce will rely on sched_clock(). And its clock can have a per nanosecond granularity. To prepare for this, we need to have a cputime_t implementation that has this precision. ia64 virtual cputime accounting already uses that granularity so all we need is to librarize its implementation in the asm generic headers. Also librarize the default per jiffy granularity cputime_t as well so that we can easily pick either implementation depending on the cputime accounting config we choose. 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 Cc: Tony Luck Cc: Fenghua Yu --- include/asm-generic/cputime.h | 62 +--------------------- include/asm-generic/cputime_jiffies.h | 66 ++++++++++++++++++++++++ include/asm-generic/cputime_nsecs.h | 96 +++++++++++++++++++++++++++++++++++ 3 files changed, 163 insertions(+), 61 deletions(-) create mode 100644 include/asm-generic/cputime_jiffies.h create mode 100644 include/asm-generic/cputime_nsecs.h (limited to 'include/asm-generic') diff --git a/include/asm-generic/cputime.h b/include/asm-generic/cputime.h index 9a62937..c6eddf5 100644 --- a/include/asm-generic/cputime.h +++ b/include/asm-generic/cputime.h @@ -4,66 +4,6 @@ #include #include -typedef unsigned long __nocast cputime_t; - -#define cputime_one_jiffy jiffies_to_cputime(1) -#define cputime_to_jiffies(__ct) (__force unsigned long)(__ct) -#define cputime_to_scaled(__ct) (__ct) -#define jiffies_to_cputime(__hz) (__force cputime_t)(__hz) - -typedef u64 __nocast cputime64_t; - -#define cputime64_to_jiffies64(__ct) (__force u64)(__ct) -#define jiffies64_to_cputime64(__jif) (__force cputime64_t)(__jif) - -#define nsecs_to_cputime64(__ct) \ - jiffies64_to_cputime64(nsecs_to_jiffies64(__ct)) - - -/* - * Convert cputime to microseconds and back. - */ -#define cputime_to_usecs(__ct) \ - jiffies_to_usecs(cputime_to_jiffies(__ct)) -#define usecs_to_cputime(__usec) \ - jiffies_to_cputime(usecs_to_jiffies(__usec)) -#define usecs_to_cputime64(__usec) \ - jiffies64_to_cputime64(nsecs_to_jiffies64((__usec) * 1000)) - -/* - * Convert cputime to seconds and back. - */ -#define cputime_to_secs(jif) (cputime_to_jiffies(jif) / HZ) -#define secs_to_cputime(sec) jiffies_to_cputime((sec) * HZ) - -/* - * Convert cputime to timespec and back. - */ -#define timespec_to_cputime(__val) \ - jiffies_to_cputime(timespec_to_jiffies(__val)) -#define cputime_to_timespec(__ct,__val) \ - jiffies_to_timespec(cputime_to_jiffies(__ct),__val) - -/* - * Convert cputime to timeval and back. - */ -#define timeval_to_cputime(__val) \ - jiffies_to_cputime(timeval_to_jiffies(__val)) -#define cputime_to_timeval(__ct,__val) \ - jiffies_to_timeval(cputime_to_jiffies(__ct),__val) - -/* - * Convert cputime to clock and back. - */ -#define cputime_to_clock_t(__ct) \ - jiffies_to_clock_t(cputime_to_jiffies(__ct)) -#define clock_t_to_cputime(__x) \ - jiffies_to_cputime(clock_t_to_jiffies(__x)) - -/* - * Convert cputime64 to clock. - */ -#define cputime64_to_clock_t(__ct) \ - jiffies_64_to_clock_t(cputime64_to_jiffies64(__ct)) +#include #endif diff --git a/include/asm-generic/cputime_jiffies.h b/include/asm-generic/cputime_jiffies.h new file mode 100644 index 0000000..b747f1f --- /dev/null +++ b/include/asm-generic/cputime_jiffies.h @@ -0,0 +1,66 @@ +#ifndef _ASM_GENERIC_CPUTIME_JIFFIES_H +#define _ASM_GENERIC_CPUTIME_JIFFIES_H + +typedef unsigned long __nocast cputime_t; + +#define cputime_one_jiffy jiffies_to_cputime(1) +#define cputime_to_jiffies(__ct) (__force unsigned long)(__ct) +#define cputime_to_scaled(__ct) (__ct) +#define jiffies_to_cputime(__hz) (__force cputime_t)(__hz) + +typedef u64 __nocast cputime64_t; + +#define cputime64_to_jiffies64(__ct) (__force u64)(__ct) +#define jiffies64_to_cputime64(__jif) (__force cputime64_t)(__jif) + +#define nsecs_to_cputime64(__ct) \ + jiffies64_to_cputime64(nsecs_to_jiffies64(__ct)) + + +/* + * Convert cputime to microseconds and back. + */ +#define cputime_to_usecs(__ct) \ + jiffies_to_usecs(cputime_to_jiffies(__ct)) +#define usecs_to_cputime(__usec) \ + jiffies_to_cputime(usecs_to_jiffies(__usec)) +#define usecs_to_cputime64(__usec) \ + jiffies64_to_cputime64(nsecs_to_jiffies64((__usec) * 1000)) + +/* + * Convert cputime to seconds and back. + */ +#define cputime_to_secs(jif) (cputime_to_jiffies(jif) / HZ) +#define secs_to_cputime(sec) jiffies_to_cputime((sec) * HZ) + +/* + * Convert cputime to timespec and back. + */ +#define timespec_to_cputime(__val) \ + jiffies_to_cputime(timespec_to_jiffies(__val)) +#define cputime_to_timespec(__ct,__val) \ + jiffies_to_timespec(cputime_to_jiffies(__ct),__val) + +/* + * Convert cputime to timeval and back. + */ +#define timeval_to_cputime(__val) \ + jiffies_to_cputime(timeval_to_jiffies(__val)) +#define cputime_to_timeval(__ct,__val) \ + jiffies_to_timeval(cputime_to_jiffies(__ct),__val) + +/* + * Convert cputime to clock and back. + */ +#define cputime_to_clock_t(__ct) \ + jiffies_to_clock_t(cputime_to_jiffies(__ct)) +#define clock_t_to_cputime(__x) \ + jiffies_to_cputime(clock_t_to_jiffies(__x)) + +/* + * Convert cputime64 to clock. + */ +#define cputime64_to_clock_t(__ct) \ + jiffies_64_to_clock_t(cputime64_to_jiffies64(__ct)) + +#endif diff --git a/include/asm-generic/cputime_nsecs.h b/include/asm-generic/cputime_nsecs.h new file mode 100644 index 0000000..c73d182 --- /dev/null +++ b/include/asm-generic/cputime_nsecs.h @@ -0,0 +1,96 @@ +/* + * Definitions for measuring cputime in nsecs resolution. + * + * Based on + * + * Copyright (C) 2007 FUJITSU LIMITED + * Copyright (C) 2007 Hidetoshi Seto + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + * + */ + +#ifndef _ASM_GENERIC_CPUTIME_NSECS_H +#define _ASM_GENERIC_CPUTIME_NSECS_H + +typedef u64 __nocast cputime_t; +typedef u64 __nocast cputime64_t; + +#define cputime_one_jiffy jiffies_to_cputime(1) + +/* + * Convert cputime <-> jiffies (HZ) + */ +#define cputime_to_jiffies(__ct) \ + ((__force u64)(__ct) / (NSEC_PER_SEC / HZ)) +#define jiffies_to_cputime(__jif) \ + (__force cputime_t)((__jif) * (NSEC_PER_SEC / HZ)) +#define cputime64_to_jiffies64(__ct) \ + ((__force u64)(__ct) / (NSEC_PER_SEC / HZ)) +#define jiffies64_to_cputime64(__jif) \ + (__force cputime64_t)((__jif) * (NSEC_PER_SEC / HZ)) + +/* + * Convert cputime <-> microseconds + */ +#define cputime_to_usecs(__ct) \ + ((__force u64)(__ct) / NSEC_PER_USEC) +#define usecs_to_cputime(__usecs) \ + (__force cputime_t)((__usecs) * NSEC_PER_USEC) +#define usecs_to_cputime64(__usecs) \ + (__force cputime64_t)((__usecs) * NSEC_PER_USEC) + +/* + * Convert cputime <-> seconds + */ +#define cputime_to_secs(__ct) \ + ((__force u64)(__ct) / NSEC_PER_SEC) +#define secs_to_cputime(__secs) \ + (__force cputime_t)((__secs) * NSEC_PER_SEC) + +/* + * Convert cputime <-> timespec (nsec) + */ +static inline cputime_t timespec_to_cputime(const struct timespec *val) +{ + u64 ret = val->tv_sec * NSEC_PER_SEC + val->tv_nsec; + return (__force cputime_t) ret; +} +static inline void cputime_to_timespec(const cputime_t ct, struct timespec *val) +{ + val->tv_sec = (__force u64) ct / NSEC_PER_SEC; + val->tv_nsec = (__force u64) ct % NSEC_PER_SEC; +} + +/* + * Convert cputime <-> timeval (msec) + */ +static inline cputime_t timeval_to_cputime(struct timeval *val) +{ + u64 ret = val->tv_sec * NSEC_PER_SEC + val->tv_usec * NSEC_PER_USEC; + return (__force cputime_t) ret; +} +static inline void cputime_to_timeval(const cputime_t ct, struct timeval *val) +{ + val->tv_sec = (__force u64) ct / NSEC_PER_SEC; + val->tv_usec = ((__force u64) ct % NSEC_PER_SEC) / NSEC_PER_USEC; +} + +/* + * Convert cputime <-> clock (USER_HZ) + */ +#define cputime_to_clock_t(__ct) \ + ((__force u64)(__ct) / (NSEC_PER_SEC / USER_HZ)) +#define clock_t_to_cputime(__x) \ + (__force cputime_t)((__x) * (NSEC_PER_SEC / USER_HZ)) + +/* + * Convert cputime64 to clock. + */ +#define cputime64_to_clock_t(__ct) \ + cputime_to_clock_t((__force cputime_t)__ct) + +#endif -- cgit v1.1 From ae8dda5c473bf1a85913942adcaac449e5754bf3 Mon Sep 17 00:00:00 2001 From: Frederic Weisbecker Date: Wed, 16 Jan 2013 18:02:04 +0100 Subject: cputime: Move default nsecs_to_cputime() to jiffies based cputime file If the architecture doesn't provide an implementation of nsecs_to_cputime(), the cputime accounting core uses a default one that converts the nanoseconds to jiffies. However this only makes sense if we use the jiffies based cputime. For now it doesn't matter much because this API is only called on code that uses jiffies based cputime accounting. But the code may evolve and this API may be used more broadly in the future. Keeping this default implementation around is very error prone as it may introduce a bug and hide it on architectures that don't override this API. Fix this by moving this definition to the jiffies based cputime headers as it is the only place where it belongs to. 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 --- include/asm-generic/cputime_jiffies.h | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) (limited to 'include/asm-generic') diff --git a/include/asm-generic/cputime_jiffies.h b/include/asm-generic/cputime_jiffies.h index b747f1f..272ecba 100644 --- a/include/asm-generic/cputime_jiffies.h +++ b/include/asm-generic/cputime_jiffies.h @@ -13,8 +13,14 @@ typedef u64 __nocast cputime64_t; #define cputime64_to_jiffies64(__ct) (__force u64)(__ct) #define jiffies64_to_cputime64(__jif) (__force cputime64_t)(__jif) -#define nsecs_to_cputime64(__ct) \ - jiffies64_to_cputime64(nsecs_to_jiffies64(__ct)) + +/* + * Convert nanoseconds to cputime + */ +#define nsecs_to_cputime64(__nsec) \ + jiffies64_to_cputime64(nsecs_to_jiffies64(__nsec)) +#define nsecs_to_cputime(__nsec) \ + jiffies_to_cputime(nsecs_to_jiffies(__nsec)) /* -- cgit v1.1 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 --- include/asm-generic/cputime.h | 8 +++++++- include/asm-generic/cputime_nsecs.h | 8 ++++++++ 2 files changed, 15 insertions(+), 1 deletion(-) (limited to 'include/asm-generic') diff --git a/include/asm-generic/cputime.h b/include/asm-generic/cputime.h index c6eddf5..5196943 100644 --- a/include/asm-generic/cputime.h +++ b/include/asm-generic/cputime.h @@ -4,6 +4,12 @@ #include #include -#include +#ifndef CONFIG_VIRT_CPU_ACCOUNTING +# include +#endif + +#ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN +# include +#endif #endif diff --git a/include/asm-generic/cputime_nsecs.h b/include/asm-generic/cputime_nsecs.h index c73d182..b6485ca 100644 --- a/include/asm-generic/cputime_nsecs.h +++ b/include/asm-generic/cputime_nsecs.h @@ -26,6 +26,7 @@ typedef u64 __nocast cputime64_t; */ #define cputime_to_jiffies(__ct) \ ((__force u64)(__ct) / (NSEC_PER_SEC / HZ)) +#define cputime_to_scaled(__ct) (__ct) #define jiffies_to_cputime(__jif) \ (__force cputime_t)((__jif) * (NSEC_PER_SEC / HZ)) #define cputime64_to_jiffies64(__ct) \ @@ -33,6 +34,13 @@ typedef u64 __nocast cputime64_t; #define jiffies64_to_cputime64(__jif) \ (__force cputime64_t)((__jif) * (NSEC_PER_SEC / HZ)) + +/* + * Convert cputime <-> nanoseconds + */ +#define nsecs_to_cputime(__nsecs) ((__force u64)(__nsecs)) + + /* * Convert cputime <-> microseconds */ -- cgit v1.1