[PATCH] improve idle cputime accounting

Distinguish the cputime of the idle process where idle is actually using
cpu cycles from the cputime where idle is sleeping on an enabled wait psw.
The former is accounted as system time, the later as idle time.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 3 insertions, 2 deletions

diff --git a/arch/s390/kernel/entry64.S b/arch/s390/kernel/entry64.S
index 16bb4fd1a403..ae83c195171c 100644
--- a/arch/s390/kernel/entry64.S
+++ b/arch/s390/kernel/entry64.S
@@ -559,8 +559,8 @@ kernel_per:
  */
         .globl io_int_handler
 io_int_handler:
-        stpt    __LC_ASYNC_ENTER_TIMER
         stck    __LC_INT_CLOCK
+        stpt    __LC_ASYNC_ENTER_TIMER
         SAVE_ALL_BASE __LC_SAVE_AREA+32
         SAVE_ALL_ASYNC __LC_IO_OLD_PSW,__LC_SAVE_AREA+32
         CREATE_STACK_FRAME __LC_IO_OLD_PSW,__LC_SAVE_AREA+32
@@ -721,8 +721,8 @@ io_notify_resume:
  */
         .globl  ext_int_handler
 ext_int_handler:
-        stpt    __LC_ASYNC_ENTER_TIMER
         stck    __LC_INT_CLOCK
+        stpt    __LC_ASYNC_ENTER_TIMER
         SAVE_ALL_BASE __LC_SAVE_AREA+32
         SAVE_ALL_ASYNC __LC_EXT_OLD_PSW,__LC_SAVE_AREA+32
         CREATE_STACK_FRAME __LC_EXT_OLD_PSW,__LC_SAVE_AREA+32
@@ -746,6 +746,7 @@ __critical_end:
  */
         .globl mcck_int_handler
 mcck_int_handler:
+        stck    __LC_INT_CLOCK
         la      %r1,4095                # revalidate r1
         spt     __LC_CPU_TIMER_SAVE_AREA-4095(%r1)      # revalidate cpu timer
         lmg     %r0,%r15,__LC_GPREGS_SAVE_AREA-4095(%r1)# revalidate gprs