Commit 49253925 authored Jan 27, 2015 by Martin Schwidefsky

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 c742b31c
"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>

parent 8cc748aa

arch/s390/kernel/vdso64/clock_gettime.S

+2 −4

Original line number	Diff line number	Diff line
		@@ -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