diff options
| author | Linus Torvalds <torvalds@linux-foundation.org> | 2019-05-06 16:31:44 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2019-05-06 16:31:44 -0700 |
| commit | db10ad041b318a07985363e243742a07f4b0f44b (patch) | |
| tree | 89fe987edb34e0b41885eface16a51df129c17c1 | |
| parent | ba3934de557a2074b89d67e29e5ce119f042d057 (diff) | |
| parent | 81423c37415fe45057d64196ae0ce8e17a9c7148 (diff) | |
Merge branch 'x86-timers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 timer updates from Ingo Molnar:
"Two changes: an LTO improvement, plus the new 'nowatchdog' boot option
to disable the clocksource watchdog"
* 'x86-timers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/timer: Don't inline __const_udelay()
x86/tsc: Add option to disable tsc clocksource watchdog
| -rw-r--r-- | Documentation/admin-guide/kernel-parameters.txt | 4 | ||||
| -rw-r--r-- | arch/x86/kernel/tsc.c | 5 | ||||
| -rw-r--r-- | arch/x86/lib/delay.c | 2 |
3 files changed, 9 insertions, 2 deletions
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 420bb17440fd..58e69ec8b7a0 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -4740,6 +4740,10 @@ [x86] unstable: mark the TSC clocksource as unstable, this marks the TSC unconditionally unstable at bootup and avoids any further wobbles once the TSC watchdog notices. + [x86] nowatchdog: disable clocksource watchdog. Used + in situations with strict latency requirements (where + interruptions from clocksource watchdog are not + acceptable). turbografx.map[2|3]= [HW,JOY] TurboGraFX parallel port interface diff --git a/arch/x86/kernel/tsc.c b/arch/x86/kernel/tsc.c index 3fae23834069..aab0c82e0a0d 100644 --- a/arch/x86/kernel/tsc.c +++ b/arch/x86/kernel/tsc.c @@ -283,6 +283,7 @@ int __init notsc_setup(char *str) __setup("notsc", notsc_setup); static int no_sched_irq_time; +static int no_tsc_watchdog; static int __init tsc_setup(char *str) { @@ -292,6 +293,8 @@ static int __init tsc_setup(char *str) no_sched_irq_time = 1; if (!strcmp(str, "unstable")) mark_tsc_unstable("boot parameter"); + if (!strcmp(str, "nowatchdog")) + no_tsc_watchdog = 1; return 1; } @@ -1349,7 +1352,7 @@ static int __init init_tsc_clocksource(void) if (tsc_unstable) goto unreg; - if (tsc_clocksource_reliable) + if (tsc_clocksource_reliable || no_tsc_watchdog) clocksource_tsc.flags &= ~CLOCK_SOURCE_MUST_VERIFY; if (boot_cpu_has(X86_FEATURE_NONSTOP_TSC_S3)) diff --git a/arch/x86/lib/delay.c b/arch/x86/lib/delay.c index f5b7f1b3b6d7..b7375dc6898f 100644 --- a/arch/x86/lib/delay.c +++ b/arch/x86/lib/delay.c @@ -162,7 +162,7 @@ void __delay(unsigned long loops) } EXPORT_SYMBOL(__delay); -void __const_udelay(unsigned long xloops) +noinline void __const_udelay(unsigned long xloops) { unsigned long lpj = this_cpu_read(cpu_info.loops_per_jiffy) ? : loops_per_jiffy; int d0; |