diff options
| author | Thomas Gleixner <tglx@linutronix.de> | 2008-05-18 19:27:48 +0200 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2008-05-23 14:08:06 +0200 |
| commit | b6db80ee1331e7beaeb91b4b3d946dd16c72e388 (patch) | |
| tree | 89edfa1ff482b13df41006c7b0ba6786c77201cc /arch/x86 | |
| parent | 75d3bce2fc0a80f435fe12f2c9ed2632c8ac29e4 (diff) | |
| download | linux-b6db80ee1331e7beaeb91b4b3d946dd16c72e388.tar.bz2 | |
x86: fix setup of cyc2ns in tsc_64.c
When the TSC is calibrated against the PIT due to the nonavailability
of PMTIMER/HPET or due to SMI interference then the setup of the per
CPU cyc2ns variables is skipped. This is unlikely to happen but it
would definitely render sched_clock() unusable.
This was introduced with commit 53d517cdbaac704352b3d0c10fecb99e0b54572e
x86: scale cyc_2_nsec according to CPU frequency
Update the per CPU cyc2ns variables in all exit pathes of tsc_calibrate.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@kernel.org
Diffstat (limited to 'arch/x86')
| -rw-r--r-- | arch/x86/kernel/tsc_64.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/arch/x86/kernel/tsc_64.c b/arch/x86/kernel/tsc_64.c index fcc16e58609e..1784b8077a12 100644 --- a/arch/x86/kernel/tsc_64.c +++ b/arch/x86/kernel/tsc_64.c @@ -227,14 +227,14 @@ void __init tsc_calibrate(void) /* hpet or pmtimer available ? */ if (!hpet && !pm1 && !pm2) { printk(KERN_INFO "TSC calibrated against PIT\n"); - return; + goto out; } /* Check, whether the sampling was disturbed by an SMI */ if (tsc1 == ULONG_MAX || tsc2 == ULONG_MAX) { printk(KERN_WARNING "TSC calibration disturbed by SMI, " "using PIT calibration result\n"); - return; + goto out; } tsc2 = (tsc2 - tsc1) * 1000000L; @@ -255,6 +255,7 @@ void __init tsc_calibrate(void) tsc_khz = tsc2 / tsc1; +out: for_each_possible_cpu(cpu) set_cyc2ns_scale(tsc_khz, cpu); } |