taskstats scaled time cleanup
This moves the ability to scale cputime into generic code. This allows us
to fix the issue in kernel/timer.c (noticed by Balbir) where we could only
add an unscaled value to the scaled utime/stime.
This adds a cputime_to_scaled function. As before, the POWERPC version
does the scaling based on the last SPURR/PURR ratio calculated. The
generic and s390 (only other arch to implement asm/cputime.h) versions are
both NOPs.
Also moves the SPURR and PURR snapshots closer.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Cc: Jay Lan <jlan@engr.sgi.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/arch/powerpc/kernel/time.c b/arch/powerpc/kernel/time.c
index 5cd3db5..3b26fbd6 100644
--- a/arch/powerpc/kernel/time.c
+++ b/arch/powerpc/kernel/time.c
@@ -66,6 +66,7 @@
#include <asm/smp.h>
#include <asm/vdso_datapage.h>
#include <asm/firmware.h>
+#include <asm/cputime.h>
#ifdef CONFIG_PPC_ISERIES
#include <asm/iseries/it_lp_queue.h>
#include <asm/iseries/hv_call_xm.h>
@@ -189,6 +190,8 @@
EXPORT_SYMBOL(__cputime_sec_factor);
u64 __cputime_clockt_factor;
EXPORT_SYMBOL(__cputime_clockt_factor);
+DEFINE_PER_CPU(unsigned long, cputime_last_delta);
+DEFINE_PER_CPU(unsigned long, cputime_scaled_last_delta);
static void calc_cputime_factors(void)
{
@@ -257,8 +260,8 @@
}
account_system_time(tsk, 0, delta);
account_system_time_scaled(tsk, deltascaled);
- get_paca()->purrdelta = delta;
- get_paca()->spurrdelta = deltascaled;
+ per_cpu(cputime_last_delta, smp_processor_id()) = delta;
+ per_cpu(cputime_scaled_last_delta, smp_processor_id()) = deltascaled;
local_irq_restore(flags);
}
@@ -276,10 +279,7 @@
get_paca()->user_time = 0;
account_user_time(tsk, utime);
- /* Estimate the scaled utime by scaling the real utime based
- * on the last spurr to purr ratio */
- utimescaled = utime * get_paca()->spurrdelta / get_paca()->purrdelta;
- get_paca()->spurrdelta = get_paca()->purrdelta = 0;
+ utimescaled = cputime_to_scaled(utime);
account_user_time_scaled(tsk, utimescaled);
}