perf lock contention: Fix compiler builtin detection

__has_builtin was passed the macro rather than the actual builtin
feature. The builtin test isn't sufficient and a clang version test
also needs to be performed.

Fixes: 1bece1351c ("perf lock contention: Support old rw_semaphore type")
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Martin KaFai Lau <martin.lau@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: bpf@vger.kernel.org
Link: https://lore.kernel.org/r/20230308003020.3653271-1-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Ian Rogers 2023-03-07 16:30:20 -08:00 committed by Arnaldo Carvalho de Melo
parent e5af139715
commit 17535a33a9
1 changed files with 7 additions and 1 deletions

View File

@ -182,7 +182,13 @@ static inline struct task_struct *get_lock_owner(__u64 lock, __u32 flags)
struct mutex *mutex = (void *)lock;
owner = BPF_CORE_READ(mutex, owner.counter);
} else if (flags == LCB_F_READ || flags == LCB_F_WRITE) {
#if __has_builtin(bpf_core_type_matches)
/*
* Support for the BPF_TYPE_MATCHES argument to the
* __builtin_preserve_type_info builtin was added at some point during
* development of clang 15 and it's what is needed for
* bpf_core_type_matches.
*/
#if __has_builtin(__builtin_preserve_type_info) && __clang_major__ >= 15
if (bpf_core_type_matches(struct rw_semaphore___old)) {
struct rw_semaphore___old *rwsem = (void *)lock;
owner = (unsigned long)BPF_CORE_READ(rwsem, owner);