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author | Tvrtko Ursulin <tvrtko.ursulin@intel.com> | 2022-01-18 10:54:02 +0000 |
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committer | Tvrtko Ursulin <tvrtko.ursulin@intel.com> | 2022-01-18 10:54:02 +0000 |
commit | 647bfd26bf054313305ea9c2c4a1c71f3bbfee63 (patch) | |
tree | 49abfde459ef32c9811d06ae59dfbaf0000762ab /arch/x86/kernel/tsc_sync.c | |
parent | 3a5d604f90f90a09e35ccfdeeedbadfd06b606db (diff) | |
parent | 4efdddbce7c1329f00c458e85dcaf105aebdc0ed (diff) | |
download | linux-647bfd26bf054313305ea9c2c4a1c71f3bbfee63.tar.bz2 |
Merge drm/drm-next into drm-intel-gt-next
Maarten needs backmerge to account for header file renames/changes which
landed via drm-intel-next and are interfering with his pinning work.
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Diffstat (limited to 'arch/x86/kernel/tsc_sync.c')
-rw-r--r-- | arch/x86/kernel/tsc_sync.c | 41 |
1 files changed, 41 insertions, 0 deletions
diff --git a/arch/x86/kernel/tsc_sync.c b/arch/x86/kernel/tsc_sync.c index 50a4515fe0ad..9452dc9664b5 100644 --- a/arch/x86/kernel/tsc_sync.c +++ b/arch/x86/kernel/tsc_sync.c @@ -30,6 +30,7 @@ struct tsc_adjust { }; static DEFINE_PER_CPU(struct tsc_adjust, tsc_adjust); +static struct timer_list tsc_sync_check_timer; /* * TSC's on different sockets may be reset asynchronously. @@ -77,6 +78,46 @@ void tsc_verify_tsc_adjust(bool resume) } } +/* + * Normally the tsc_sync will be checked every time system enters idle + * state, but there is still caveat that a system won't enter idle, + * either because it's too busy or configured purposely to not enter + * idle. + * + * So setup a periodic timer (every 10 minutes) to make sure the check + * is always on. + */ + +#define SYNC_CHECK_INTERVAL (HZ * 600) + +static void tsc_sync_check_timer_fn(struct timer_list *unused) +{ + int next_cpu; + + tsc_verify_tsc_adjust(false); + + /* Run the check for all onlined CPUs in turn */ + next_cpu = cpumask_next(raw_smp_processor_id(), cpu_online_mask); + if (next_cpu >= nr_cpu_ids) + next_cpu = cpumask_first(cpu_online_mask); + + tsc_sync_check_timer.expires += SYNC_CHECK_INTERVAL; + add_timer_on(&tsc_sync_check_timer, next_cpu); +} + +static int __init start_sync_check_timer(void) +{ + if (!cpu_feature_enabled(X86_FEATURE_TSC_ADJUST) || tsc_clocksource_reliable) + return 0; + + timer_setup(&tsc_sync_check_timer, tsc_sync_check_timer_fn, 0); + tsc_sync_check_timer.expires = jiffies + SYNC_CHECK_INTERVAL; + add_timer(&tsc_sync_check_timer); + + return 0; +} +late_initcall(start_sync_check_timer); + static void tsc_sanitize_first_cpu(struct tsc_adjust *cur, s64 bootval, unsigned int cpu, bool bootcpu) { |