From: Sandipan Das Date: Fri, 18 Apr 2025 03:43:02 +0000 (+0530) Subject: perf/x86/amd/uncore: Add parameter to configure hrtimer X-Git-Tag: v6.16-rc1~196^2~31 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=e1ed37b70fb355abf2e8032a2e972cdba53ae93c;p=thirdparty%2Flinux.git perf/x86/amd/uncore: Add parameter to configure hrtimer Introduce a module parameter for configuring the hrtimer duration in milliseconds. The default duration is 60000 milliseconds and the intent is to allow users to customize it to suit jitter tolerances. It should be noted that a longer duration will reduce jitter but affect accuracy if the programmed events cause the counters to overflow multiple times in a single interval. Signed-off-by: Sandipan Das Signed-off-by: Ingo Molnar Acked-by: Peter Zijlstra Link: https://lore.kernel.org/r/6cb0101da74955fa9c8361f168ffdf481ae8a200.1744906694.git.sandipan.das@amd.com --- diff --git a/arch/x86/events/amd/uncore.c b/arch/x86/events/amd/uncore.c index e09bfbb4a4cdf..70e0af36c3781 100644 --- a/arch/x86/events/amd/uncore.c +++ b/arch/x86/events/amd/uncore.c @@ -87,6 +87,10 @@ struct amd_uncore { static struct amd_uncore uncores[UNCORE_TYPE_MAX]; +/* Interval for hrtimer, defaults to 60000 milliseconds */ +static unsigned int update_interval = 60 * MSEC_PER_SEC; +module_param(update_interval, uint, 0444); + static struct amd_uncore_pmu *event_to_amd_uncore_pmu(struct perf_event *event) { return container_of(event->pmu, struct amd_uncore_pmu, pmu); @@ -545,7 +549,7 @@ static int amd_uncore_ctx_init(struct amd_uncore *uncore, unsigned int cpu) } amd_uncore_init_hrtimer(curr); - curr->hrtimer_duration = 60LL * NSEC_PER_SEC; + curr->hrtimer_duration = (u64)update_interval * NSEC_PER_MSEC; cpumask_set_cpu(cpu, &pmu->active_mask); }