This series is a set of prerequistes for getting the new context tracking subsystem, and adaptive tickless support working on ARM.
Kevin Hilman (3): cputime_nsecs: use math64.h for nsec resolution conversion helpers init/Kconfig: virt CPU accounting: drop 64-bit requirment ARM: Kconfig: allow virt CPU accounting
arch/arm/Kconfig | 1 + include/asm-generic/cputime_nsecs.h | 28 +++++++++++++++++++--------- init/Kconfig | 2 +- 3 files changed, 21 insertions(+), 10 deletions(-)
For the nsec resolution conversions to be useable on non 64-bit architectures, the helpers in <linux/math64.h> need to be used so the right arch-specific 64-bit math helpers can be used (e.g. do_div())
Cc: Frederic Weisbecker fweisbec@gmail.com Signed-off-by: Kevin Hilman khilman@linaro.org --- include/asm-generic/cputime_nsecs.h | 28 +++++++++++++++++++--------- 1 file changed, 19 insertions(+), 9 deletions(-)
diff --git a/include/asm-generic/cputime_nsecs.h b/include/asm-generic/cputime_nsecs.h index a8ece9a..2c9e62c 100644 --- a/include/asm-generic/cputime_nsecs.h +++ b/include/asm-generic/cputime_nsecs.h @@ -16,21 +16,27 @@ #ifndef _ASM_GENERIC_CPUTIME_NSECS_H #define _ASM_GENERIC_CPUTIME_NSECS_H
+#include <linux/math64.h> + typedef u64 __nocast cputime_t; typedef u64 __nocast cputime64_t;
#define cputime_one_jiffy jiffies_to_cputime(1)
+#define cputime_div(__ct, divisor) div_u64((__force u64)__ct, divisor) +#define cputime_div_rem(__ct, divisor, remainder) \ + div_u64_rem((__force u64)__ct, divisor, remainder); + /* * Convert cputime <-> jiffies (HZ) */ #define cputime_to_jiffies(__ct) \ - ((__force u64)(__ct) / (NSEC_PER_SEC / HZ)) + cputime_div(__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) \ - ((__force u64)(__ct) / (NSEC_PER_SEC / HZ)) + cputime_div(__ct, NSEC_PER_SEC / HZ) #define jiffies64_to_cputime64(__jif) \ (__force cputime64_t)((__jif) * (NSEC_PER_SEC / HZ))
@@ -45,7 +51,7 @@ typedef u64 __nocast cputime64_t; * Convert cputime <-> microseconds */ #define cputime_to_usecs(__ct) \ - ((__force u64)(__ct) / NSEC_PER_USEC) + cputime_div(__ct, NSEC_PER_USEC) #define usecs_to_cputime(__usecs) \ (__force cputime_t)((__usecs) * NSEC_PER_USEC) #define usecs_to_cputime64(__usecs) \ @@ -55,7 +61,7 @@ typedef u64 __nocast cputime64_t; * Convert cputime <-> seconds */ #define cputime_to_secs(__ct) \ - ((__force u64)(__ct) / NSEC_PER_SEC) + cputime_div(__ct, NSEC_PER_SEC) #define secs_to_cputime(__secs) \ (__force cputime_t)((__secs) * NSEC_PER_SEC)
@@ -69,8 +75,10 @@ static inline cputime_t timespec_to_cputime(const struct timespec *val) } 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; + u32 rem; + + val->tv_sec = cputime_div_rem(ct, NSEC_PER_SEC, &rem); + val->tv_nsec = rem; }
/* @@ -83,15 +91,17 @@ static inline cputime_t timeval_to_cputime(const struct timeval *val) } 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; + u32 rem; + + val->tv_sec = cputime_div_rem(ct, NSEC_PER_SEC, &rem); + val->tv_usec = rem / NSEC_PER_USEC; }
/* * Convert cputime <-> clock (USER_HZ) */ #define cputime_to_clock_t(__ct) \ - ((__force u64)(__ct) / (NSEC_PER_SEC / USER_HZ)) + cputime_div(__ct, (NSEC_PER_SEC / USER_HZ)) #define clock_t_to_cputime(__x) \ (__force cputime_t)((__x) * (NSEC_PER_SEC / USER_HZ))
On Wed, Mar 20, 2013 at 04:34:25PM -0700, Kevin Hilman wrote:
For the nsec resolution conversions to be useable on non 64-bit architectures, the helpers in <linux/math64.h> need to be used so the right arch-specific 64-bit math helpers can be used (e.g. do_div())
Cc: Frederic Weisbecker fweisbec@gmail.com Signed-off-by: Kevin Hilman khilman@linaro.org
Ok the patch is nice!
I'm queuing it.
Thanks.
Frederic Weisbecker fweisbec@gmail.com writes:
On Wed, Mar 20, 2013 at 04:34:25PM -0700, Kevin Hilman wrote:
For the nsec resolution conversions to be useable on non 64-bit architectures, the helpers in <linux/math64.h> need to be used so the right arch-specific 64-bit math helpers can be used (e.g. do_div())
Cc: Frederic Weisbecker fweisbec@gmail.com Signed-off-by: Kevin Hilman khilman@linaro.org
Ok the patch is nice!
I'm queuing it.
Thanks, did you queue PATCH 3/3 also to remove the 64-bit limitation from VIRT_CPU_ACCOUNTING_GEN: https://lkml.org/lkml/2013/3/20/656
Kevin
2013/4/15 Kevin Hilman khilman@linaro.org:
Frederic Weisbecker fweisbec@gmail.com writes:
On Wed, Mar 20, 2013 at 04:34:25PM -0700, Kevin Hilman wrote:
For the nsec resolution conversions to be useable on non 64-bit architectures, the helpers in <linux/math64.h> need to be used so the right arch-specific 64-bit math helpers can be used (e.g. do_div())
Cc: Frederic Weisbecker fweisbec@gmail.com Signed-off-by: Kevin Hilman khilman@linaro.org
Ok the patch is nice!
I'm queuing it.
Thanks, did you queue PATCH 3/3 also to remove the 64-bit limitation from VIRT_CPU_ACCOUNTING_GEN: https://lkml.org/lkml/2013/3/20/656
Not yet, for this one I need to deeply check we haven't forgotten anything concerning cputime_t operations in 32 bits archs.
The 64-bit requirement can be removed after the conversion of the conversion of the nsec granularity cputime to work on !64_BIT
Cc: Frederic Weisbecker fweisbec@gmail.com Signed-off-by: Kevin Hilman khilman@linaro.org --- init/Kconfig | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/init/Kconfig b/init/Kconfig index 8a1dac2..1f1a328 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -329,7 +329,7 @@ config VIRT_CPU_ACCOUNTING_NATIVE
config VIRT_CPU_ACCOUNTING_GEN bool "Full dynticks CPU time accounting" - depends on HAVE_CONTEXT_TRACKING && 64BIT + depends on HAVE_CONTEXT_TRACKING select VIRT_CPU_ACCOUNTING select CONTEXT_TRACKING help
With the 64-bit requirement removed from virt CPU accounting, allow ARM platforms to enable it.
Signed-off-by: Kevin Hilman khilman@linaro.org --- arch/arm/Kconfig | 1 + 1 file changed, 1 insertion(+)
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index 5b71469..9473d55 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -59,6 +59,7 @@ config ARM select CLONE_BACKWARDS select OLD_SIGSUSPEND3 select OLD_SIGACTION + select HAVE_VIRT_CPU_ACCOUNTING help The ARM series is a line of low-power-consumption RISC chip designs licensed by ARM Ltd and targeted at embedded applications and
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