perf lock contention: Symbolize zone->lock using BTF

The struct zone is embedded in struct pglist_data which can be allocated
for each NUMA node early in the boot process.  As it's not a slab object
nor a global lock, this was not symbolized.

Since the zone->lock is often contended, it'd be nice if we can
symbolize it.  On NUMA systems, node_data array will have pointers for
struct pglist_data.  By following the pointer, it can calculate the
address of each zone and its lock using BTF.  On UMA, it can just use
contig_page_data and its zones.

The following example shows the zone lock contention at the end.

  $ sudo ./perf lock con -abl -E 5 -- ./perf bench sched messaging
  # Running 'sched/messaging' benchmark:
  # 20 sender and receiver processes per group
  # 10 groups == 400 processes run

       Total time: 0.038 [sec]
   contended   total wait     max wait     avg wait            address   symbol

        5167     18.17 ms     10.27 us      3.52 us   ffff953340052d00   &kmem_cache_node (spinlock)
          38     11.75 ms    465.49 us    309.13 us   ffff95334060c480   &sock_inode_cache (spinlock)
        3916     10.13 ms     10.43 us      2.59 us   ffff953342aecb40   &kmem_cache_node (spinlock)
        2963     10.02 ms     13.75 us      3.38 us   ffff9533d2344098   &kmalloc-rnd-08-2k (spinlock)
         216      5.05 ms     99.49 us     23.39 us   ffff9542bf7d65d0   zone_lock (spinlock)

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <song@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: bpf@vger.kernel.org
Cc: linux-mm@kvack.org
Link: https://lore.kernel.org/r/20250401063055.7431-1-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 9 insertions, 0 deletions

diff --git a/tools/perf/util/bpf_skel/vmlinux/vmlinux.h b/tools/perf/util/bpf_skel/vmlinux/vmlinux.h
index 7b81d3173917..a59ce912be18 100644
--- a/tools/perf/util/bpf_skel/vmlinux/vmlinux.h
+++ b/tools/perf/util/bpf_skel/vmlinux/vmlinux.h
@@ -203,4 +203,13 @@ struct bpf_iter__kmem_cache {
 	struct kmem_cache *s;
 } __attribute__((preserve_access_index));
 
+struct zone {
+	spinlock_t lock;
+} __attribute__((preserve_access_index));
+
+struct pglist_data {
+	struct zone node_zones[6]; /* value for all possible config */
+	int nr_zones;
+} __attribute__((preserve_access_index));
+
 #endif // __VMLINUX_H