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It is possible for allocation and free to occur on different CPUs, and using local_clock() to record timestamps may cause confusion. ktime_get_boot_fast_ns() is based on clock sources and can be used reliably and accurately for comparison across CPUs. Signed-off-by: Juntong Deng --- mm/kfence/core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/mm/kfence/core.c b/mm/kfence/core.c index 3872528d0963..041c03394193 100644 --- a/mm/kfence/core.c +++ b/mm/kfence/core.c @@ -295,7 +295,7 @@ metadata_update_state(struct kfence_metadata *meta, enum kfence_object_state nex track->num_stack_entries = num_stack_entries; track->pid = task_pid_nr(current); track->cpu = raw_smp_processor_id(); - track->ts_nsec = local_clock(); /* Same source as printk timestamps. */ + track->ts_nsec = ktime_get_boot_fast_ns(); /* * Pairs with READ_ONCE() in -- 2.39.2