[S390] pm: ignore time spend in suspended state

The time a system has been suspended should not show up in any
of the cputime accounting fields. The time of inactivity is definitly
not any form of real cputime nor is it idle time.

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

1 files changed, 17 insertions, 4 deletions

diff --git a/arch/s390/kernel/swsusp_asm64.S b/arch/s390/kernel/swsusp_asm64.S
index fe927d0bc20b..008e35af339f 100644
--- a/arch/s390/kernel/swsusp_asm64.S
+++ b/arch/s390/kernel/swsusp_asm64.S
@@ -69,8 +69,21 @@ swsusp_arch_suspend:
         stmg    %r0,%r15,0x280(%r1)             /* store general registers */
 
         stpt    0x328(%r1)                      /* store timer */
+        stck    __SF_EMPTY(%r15)                /* store clock */
         stckc   0x330(%r1)                      /* store clock comparator */
 
+        /* Update cputime accounting before going to sleep */
+        lg      %r0,__LC_LAST_UPDATE_TIMER
+        slg     %r0,0x328(%r1)
+        alg     %r0,__LC_SYSTEM_TIMER
+        stg     %r0,__LC_SYSTEM_TIMER
+        mvc     __LC_LAST_UPDATE_TIMER(8),0x328(%r1)
+        lg      %r0,__LC_LAST_UPDATE_CLOCK
+        slg     %r0,__SF_EMPTY(%r15)
+        alg     %r0,__LC_STEAL_TIMER
+        stg     %r0,__LC_STEAL_TIMER
+        mvc     __LC_LAST_UPDATE_CLOCK(8),__SF_EMPTY(%r15)
+
         /* Activate DAT */
         stosm   __SF_EMPTY(%r15),0x04
 
@@ -200,8 +213,11 @@ restart_suspend:
 
 restore_registers:
         /* Restore registers */
-        lghi    %r13,0x1000             /* %r1 = pointer to save arae */
+        lghi    %r13,0x1000             /* %r1 = pointer to save area */
 
+        /* Ignore time spent in suspended state. */
+        llgf    %r1,0x318(%r13)
+        stck    __LC_LAST_UPDATE_CLOCK(%r1)
         spt     0x328(%r13)             /* reprogram timer */
         //sckc  0x330(%r13)             /* set clock comparator */
 
@@ -229,9 +245,6 @@ restore_registers:
         /* Load old stack */
         lg      %r15,0x2f8(%r13)
 
-        /* Pointer to save area */
-        lghi    %r13,0x1000
-
         /* Restore prefix register */
         spx     0x318(%r13)