diff options
Diffstat (limited to 'arch/x86_64/kernel/smpboot.c')
-rw-r--r-- | arch/x86_64/kernel/smpboot.c | 8 |
1 files changed, 7 insertions, 1 deletions
diff --git a/arch/x86_64/kernel/smpboot.c b/arch/x86_64/kernel/smpboot.c index e6af93b51dc..994728564d6 100644 --- a/arch/x86_64/kernel/smpboot.c +++ b/arch/x86_64/kernel/smpboot.c @@ -335,7 +335,13 @@ static __cpuinit void sync_tsc(unsigned int master) static void __cpuinit tsc_sync_wait(void) { - if (notscsync || !cpu_has_tsc) + /* + * When the CPU has synchronized TSCs assume the BIOS + * or the hardware already synced. Otherwise we could + * mess up a possible perfect synchronization with a + * not-quite-perfect algorithm. + */ + if (notscsync || !cpu_has_tsc || !unsynchronized_tsc()) return; sync_tsc(0); } |