perf core: Allocate perf_event in the target node memory

For cpu events, it'd better allocating them in the corresponding node
memory as they would be mostly accessed by the target cpu.  Although
perf tools sets the cpu affinity before calling perf_event_open, there
are places it doesn't (notably perf record) and we should consider
other external users too.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20210311115413.444407-2-namhyung@kernel.org

diff --git a/kernel/events/core.c b/kernel/events/core.c
index f526ddb50d5e050a345852f52ad55a160b9f7b28..6182cb199f7247876dcd0dfb5ff644c27890c3bd 100644 (file)
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -11288,13 +11288,16 @@ perf_event_alloc(struct perf_event_attr *attr, int cpu,
        struct perf_event *event;
        struct hw_perf_event *hwc;
        long err = -EINVAL;
+       int node;
 
        if ((unsigned)cpu >= nr_cpu_ids) {
                if (!task || cpu != -1)
                        return ERR_PTR(-EINVAL);
        }
 
-       event = kmem_cache_zalloc(perf_event_cache, GFP_KERNEL);
+       node = (cpu >= 0) ? cpu_to_node(cpu) : -1;
+       event = kmem_cache_alloc_node(perf_event_cache, GFP_KERNEL | __GFP_ZERO,
+                                     node);
        if (!event)
                return ERR_PTR(-ENOMEM);