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e53de7b)
It seems BPF CO-RE reloc doesn't work well with the pattern that gets
the field-offset only. Use offsetof() to make it explicit so that
the compiler would generate the correct code.
Fixes:
0c1228486befa3d6 ("perf lock contention: Support pre-5.14 kernels")
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: Hao Luo <haoluo@google.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <song@kernel.org>
Cc: bpf@vger.kernel.org
Co-developed-by: Andrii Nakryiko <andrii.nakryiko@gmail.com>
Link: https://lore.kernel.org/r/20230427234833.1576130-2-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
SEC("raw_tp/bpf_test_finish")
int BPF_PROG(collect_lock_syms)
{
SEC("raw_tp/bpf_test_finish")
int BPF_PROG(collect_lock_syms)
{
+ __u64 lock_addr, lock_off;
+ if (bpf_core_field_exists(struct rq___new, __lock))
+ lock_off = offsetof(struct rq___new, __lock);
+ else
+ lock_off = offsetof(struct rq___old, lock);
+
for (int i = 0; i < MAX_CPUS; i++) {
struct rq *rq = bpf_per_cpu_ptr(&runqueues, i);
for (int i = 0; i < MAX_CPUS; i++) {
struct rq *rq = bpf_per_cpu_ptr(&runqueues, i);
- struct rq___new *rq_new = (void *)rq;
- struct rq___old *rq_old = (void *)rq;
- if (bpf_core_field_exists(rq_new->__lock))
- lock_addr = (__u64)&rq_new->__lock;
- else
- lock_addr = (__u64)&rq_old->lock;
+ lock_addr = (__u64)(void *)rq + lock_off;
lock_flag = LOCK_CLASS_RQLOCK;
bpf_map_update_elem(&lock_syms, &lock_addr, &lock_flag, BPF_ANY);
}
lock_flag = LOCK_CLASS_RQLOCK;
bpf_map_update_elem(&lock_syms, &lock_addr, &lock_flag, BPF_ANY);
}