diff options
| author | Linus Torvalds <torvalds@linux-foundation.org> | 2015-07-12 10:02:38 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2015-07-12 10:02:38 -0700 |
| commit | 1daa1cfb7ab3b9f9b4c7e7a3f136e4e0066b123c (patch) | |
| tree | 8deb1250fee8f49a50031c47d35863ceff7b3990 /arch/x86/kernel/tsc.c | |
| parent | 7b732169e9d1f0f6614a8e85a9e65a9d755b3d86 (diff) | |
| parent | 69711ca19b06d1b33d8f21213b540b5d1c638dbf (diff) | |
| download | kernel_replicant_linux-1daa1cfb7ab3b9f9b4c7e7a3f136e4e0066b123c.tar.gz kernel_replicant_linux-1daa1cfb7ab3b9f9b4c7e7a3f136e4e0066b123c.tar.bz2 kernel_replicant_linux-1daa1cfb7ab3b9f9b4c7e7a3f136e4e0066b123c.zip | |
Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Thomas Gleixner:
- the high latency PIT detection fix, which slipped through the cracks
for rc1
- a regression fix for the early printk mechanism
- the x86 part to plug irq/vector related hotplug races
- move the allocation of the espfix pages on cpu hotplug to non atomic
context. The current code triggers a might_sleep() warning.
- a series of KASAN fixes addressing boot crashes and usability
- a trivial typo fix for Kconfig help text
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/kconfig: Fix typo in the CONFIG_CMDLINE_BOOL help text
x86/irq: Retrieve irq data after locking irq_desc
x86/irq: Use proper locking in check_irq_vectors_for_cpu_disable()
x86/irq: Plug irq vector hotplug race
x86/earlyprintk: Allow early_printk() to use console style parameters like '115200n8'
x86/espfix: Init espfix on the boot CPU side
x86/espfix: Add 'cpu' parameter to init_espfix_ap()
x86/kasan: Move KASAN_SHADOW_OFFSET to the arch Kconfig
x86/kasan: Add message about KASAN being initialized
x86/kasan: Fix boot crash on AMD processors
x86/kasan: Flush TLBs after switching CR3
x86/kasan: Fix KASAN shadow region page tables
x86/init: Clear 'init_level4_pgt' earlier
x86/tsc: Let high latency PIT fail fast in quick_pit_calibrate()
Diffstat (limited to 'arch/x86/kernel/tsc.c')
| -rw-r--r-- | arch/x86/kernel/tsc.c | 11 |
1 files changed, 10 insertions, 1 deletions
diff --git a/arch/x86/kernel/tsc.c b/arch/x86/kernel/tsc.c index 505449700e0c..7437b41f6a47 100644 --- a/arch/x86/kernel/tsc.c +++ b/arch/x86/kernel/tsc.c @@ -598,10 +598,19 @@ static unsigned long quick_pit_calibrate(void) if (!pit_expect_msb(0xff-i, &delta, &d2)) break; + delta -= tsc; + + /* + * Extrapolate the error and fail fast if the error will + * never be below 500 ppm. + */ + if (i == 1 && + d1 + d2 >= (delta * MAX_QUICK_PIT_ITERATIONS) >> 11) + return 0; + /* * Iterate until the error is less than 500 ppm */ - delta -= tsc; if (d1+d2 >= delta >> 11) continue; |