Hi, it seems that the patch bellow is missing in the stable tree. It fixes an issue introduced in 2.6.37-rc1 and the fix went in in 3.3-rc1. The following patch is on top of stable/linux-3.0.y but it should apply cleanly to other branches as well. --- >From de950634336e8237d7ab6b0092c4337da1aaa3d2 Mon Sep 17 00:00:00 2001 From: Andreas Schwab <[email protected]> Date: Fri, 9 Dec 2011 11:35:08 +0000 Subject: [PATCH] powerpc: Fix wrong divisor in usecs_to_cputime
commit 9f5072d4f63f28d30d343573830ac6c85fc0deff upstream. Commit d57af9b (taskstats: use real microsecond granularity for CPU times) renamed msecs_to_cputime to usecs_to_cputime, but failed to update all numbers on the way. This causes nonsensical cpu idle/iowait values to be displayed in /proc/stat (the only user of usecs_to_cputime so far). This also renames __cputime_msec_factor to __cputime_usec_factor, adapting its value and using it directly in cputime_to_usecs instead of doing two multiplications. Signed-off-by: Andreas Schwab <[email protected]> Acked-by: Anton Blanchard <[email protected]> Signed-off-by: Benjamin Herrenschmidt <[email protected]> --- arch/powerpc/include/asm/cputime.h | 6 +++--- arch/powerpc/kernel/time.c | 10 +++++----- 2 files changed, 8 insertions(+), 8 deletions(-) diff --git a/arch/powerpc/include/asm/cputime.h b/arch/powerpc/include/asm/cputime.h index 1cf20bd..33a3580 100644 --- a/arch/powerpc/include/asm/cputime.h +++ b/arch/powerpc/include/asm/cputime.h @@ -126,11 +126,11 @@ static inline u64 cputime64_to_jiffies64(const cputime_t ct) /* * Convert cputime <-> microseconds */ -extern u64 __cputime_msec_factor; +extern u64 __cputime_usec_factor; static inline unsigned long cputime_to_usecs(const cputime_t ct) { - return mulhdu(ct, __cputime_msec_factor) * USEC_PER_MSEC; + return mulhdu(ct, __cputime_usec_factor); } static inline cputime_t usecs_to_cputime(const unsigned long us) @@ -143,7 +143,7 @@ static inline cputime_t usecs_to_cputime(const unsigned long us) sec = us / 1000000; if (ct) { ct *= tb_ticks_per_sec; - do_div(ct, 1000); + do_div(ct, 1000000); } if (sec) ct += (cputime_t) sec * tb_ticks_per_sec; diff --git a/arch/powerpc/kernel/time.c b/arch/powerpc/kernel/time.c index 2de304a..1becd7b 100644 --- a/arch/powerpc/kernel/time.c +++ b/arch/powerpc/kernel/time.c @@ -168,13 +168,13 @@ EXPORT_SYMBOL_GPL(ppc_tb_freq); #ifdef CONFIG_VIRT_CPU_ACCOUNTING /* * Factors for converting from cputime_t (timebase ticks) to - * jiffies, milliseconds, seconds, and clock_t (1/USER_HZ seconds). + * jiffies, microseconds, seconds, and clock_t (1/USER_HZ seconds). * These are all stored as 0.64 fixed-point binary fractions. */ u64 __cputime_jiffies_factor; EXPORT_SYMBOL(__cputime_jiffies_factor); -u64 __cputime_msec_factor; -EXPORT_SYMBOL(__cputime_msec_factor); +u64 __cputime_usec_factor; +EXPORT_SYMBOL(__cputime_usec_factor); u64 __cputime_sec_factor; EXPORT_SYMBOL(__cputime_sec_factor); u64 __cputime_clockt_factor; @@ -192,8 +192,8 @@ static void calc_cputime_factors(void) div128_by_32(HZ, 0, tb_ticks_per_sec, &res); __cputime_jiffies_factor = res.result_low; - div128_by_32(1000, 0, tb_ticks_per_sec, &res); - __cputime_msec_factor = res.result_low; + div128_by_32(1000000, 0, tb_ticks_per_sec, &res); + __cputime_usec_factor = res.result_low; div128_by_32(1, 0, tb_ticks_per_sec, &res); __cputime_sec_factor = res.result_low; div128_by_32(USER_HZ, 0, tb_ticks_per_sec, &res); -- 1.7.10.4 -- Michal Hocko SUSE Labs SUSE LINUX s.r.o. Lihovarska 1060/12 190 00 Praha 9 Czech Republic -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
