s390/vdso: fix clock_gettime for CLOCK_THREAD_CPUTIME_ID, -2 and -3

Git commit 8d8f2e18a6dbd3d09dd918788422e6ac8c878e96
"s390/vdso: ectg gettime support for CLOCK_THREAD_CPUTIME_ID"
broke clock_gettime for CLOCK_THREAD_CPUTIME_ID.

Git commit c742b31c03f37c5c499178f09f57381aa6c70131
"fast vdso implementation for CLOCK_THREAD_CPUTIME_ID"
introduced the ECTG for clock id -2. Correct would have been
clock id -3.

Fix the whole mess, CLOCK_THREAD_CPUTIME_ID is based on
CPUCLOCK_SCHED and can not be speed up by the vdso. A speedup
is only available for clock id -3 which is CPUCLOCK_VIRT for
the task currently running on the CPU.

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

1 files changed, 2 insertions, 4 deletions

diff --git a/arch/s390/kernel/vdso64/clock_gettime.S b/arch/s390/kernel/vdso64/clock_gettime.S
index 7699e735ae28..61541fb93dc6 100644
--- a/arch/s390/kernel/vdso64/clock_gettime.S
+++ b/arch/s390/kernel/vdso64/clock_gettime.S
@@ -25,9 +25,7 @@ __kernel_clock_gettime:
         je      4f
         cghi    %r2,__CLOCK_REALTIME
         je      5f
-        cghi    %r2,__CLOCK_THREAD_CPUTIME_ID
-        je      9f
-        cghi    %r2,-2          /* Per-thread CPUCLOCK with PID=0, VIRT=1 */
+        cghi    %r2,-3          /* Per-thread CPUCLOCK with PID=0, VIRT=1 */
         je      9f
         cghi    %r2,__CLOCK_MONOTONIC_COARSE
         je      3f
@@ -106,7 +104,7 @@ __kernel_clock_gettime:
         aghi    %r15,16
         br      %r14
 
-        /* CLOCK_THREAD_CPUTIME_ID for this thread */
+        /* CPUCLOCK_VIRT for this thread */
 9:      icm     %r0,15,__VDSO_ECTG_OK(%r5)
         jz      12f
         ear     %r2,%a4