diff options
| author | Hendrik Brueckner <brueckner@linux.vnet.ibm.com> | 2010-04-22 11:17:06 -0400 |
|---|---|---|
| committer | Martin Schwidefsky <sky@mschwide.boeblingen.de.ibm.com> | 2010-04-22 11:17:19 -0400 |
| commit | 157a1a27d5921fc94db8c14e0d01363d13de99b5 (patch) | |
| tree | 4906607e35a4bee0e84e42d59985af645c1564a2 /arch/s390/kernel/vdso64/clock_gettime.S | |
| parent | 8821d24cd261aede9b0436cd3252b17a60ccc33a (diff) | |
[S390] vdso: use ntp adjusted clock multiplier
Commit "timekeeping: Fix clock_gettime vsyscall time warp" (0696b711e)
introduced the new parameter "mult" to update_vsyscall(). This parameter
contains the internal NTP adjusted clock multiplier.
The s390x vdso did not use this adjusted multiplier. Instead, it used
the constant clock multiplier for gettimeofday() and clock_gettime()
variants. This may result in observable time warps as explained in
commit 0696b711e.
Make the NTP adjusted clock multiplier available to the s390x vdso
implementation and use it for time calculations.
Cc: <stable@kernel.org>
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Diffstat (limited to 'arch/s390/kernel/vdso64/clock_gettime.S')
| -rw-r--r-- | arch/s390/kernel/vdso64/clock_gettime.S | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/arch/s390/kernel/vdso64/clock_gettime.S b/arch/s390/kernel/vdso64/clock_gettime.S index 49106c6e6f88..f40467884a03 100644 --- a/arch/s390/kernel/vdso64/clock_gettime.S +++ b/arch/s390/kernel/vdso64/clock_gettime.S | |||
| @@ -36,7 +36,7 @@ __kernel_clock_gettime: | |||
| 36 | stck 48(%r15) /* Store TOD clock */ | 36 | stck 48(%r15) /* Store TOD clock */ |
| 37 | lg %r1,48(%r15) | 37 | lg %r1,48(%r15) |
| 38 | sg %r1,__VDSO_XTIME_STAMP(%r5) /* TOD - cycle_last */ | 38 | sg %r1,__VDSO_XTIME_STAMP(%r5) /* TOD - cycle_last */ |
| 39 | mghi %r1,1000 | 39 | msgf %r1,__VDSO_NTP_MULT(%r5) /* * NTP adjustment */ |
| 40 | srlg %r1,%r1,12 /* cyc2ns(clock,cycle_delta) */ | 40 | srlg %r1,%r1,12 /* cyc2ns(clock,cycle_delta) */ |
| 41 | alg %r1,__VDSO_XTIME_NSEC(%r5) /* + xtime */ | 41 | alg %r1,__VDSO_XTIME_NSEC(%r5) /* + xtime */ |
| 42 | lg %r0,__VDSO_XTIME_SEC(%r5) | 42 | lg %r0,__VDSO_XTIME_SEC(%r5) |
| @@ -64,7 +64,7 @@ __kernel_clock_gettime: | |||
| 64 | stck 48(%r15) /* Store TOD clock */ | 64 | stck 48(%r15) /* Store TOD clock */ |
| 65 | lg %r1,48(%r15) | 65 | lg %r1,48(%r15) |
| 66 | sg %r1,__VDSO_XTIME_STAMP(%r5) /* TOD - cycle_last */ | 66 | sg %r1,__VDSO_XTIME_STAMP(%r5) /* TOD - cycle_last */ |
| 67 | mghi %r1,1000 | 67 | msgf %r1,__VDSO_NTP_MULT(%r5) /* * NTP adjustment */ |
| 68 | srlg %r1,%r1,12 /* cyc2ns(clock,cycle_delta) */ | 68 | srlg %r1,%r1,12 /* cyc2ns(clock,cycle_delta) */ |
| 69 | alg %r1,__VDSO_XTIME_NSEC(%r5) /* + xtime */ | 69 | alg %r1,__VDSO_XTIME_NSEC(%r5) /* + xtime */ |
| 70 | lg %r0,__VDSO_XTIME_SEC(%r5) | 70 | lg %r0,__VDSO_XTIME_SEC(%r5) |