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

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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>
This commit is contained in:
Martin Schwidefsky 2015-01-27 15:15:13 +01:00
parent 8cc748aa76
commit 49253925c0
1 changed files with 2 additions and 4 deletions
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6
arch/s390/kernel/vdso64/clock_gettime.S
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@ -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