intel/perf: improve dynamic loading config detection

We're currently trying to detect dynamic loading config support by
trying to remove to test config (hard coded in the i915 driver) and
checking we get ENOENT.

This can fail if the test config was updated in Mesa but not yet in
i915.

A better way to do this is to pick an invalid ID and check for ENOENT.

Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Cc: <mesa-stable@lists.freedesktop.org>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>

diff --git a/src/intel/perf/gen_perf.c b/src/intel/perf/gen_perf.c
index cd440f7..648ec46 100644 (file)
--- a/src/intel/perf/gen_perf.c
+++ b/src/intel/perf/gen_perf.c
@@ -212,22 +212,10 @@ enumerate_sysfs_metrics(struct gen_perf *perf)
 static bool
 kernel_has_dynamic_config_support(struct gen_perf *perf, int fd)
 {
-   hash_table_foreach(perf->oa_metrics_table, entry) {
-      struct gen_perf_query_info *query = entry->data;
-      char config_path[280];
-      uint64_t config_id;
+   uint64_t invalid_config_id = UINT64_MAX;
 
-      snprintf(config_path, sizeof(config_path), "%s/metrics/%s/id",
-               perf->sysfs_dev_dir, query->guid);
-
-      /* Look for the test config, which we know we can't replace. */
-      if (read_file_uint64(config_path, &config_id) && config_id == 1) {
-         return perf->ioctl(fd, DRM_IOCTL_I915_PERF_REMOVE_CONFIG,
-                            &config_id) < 0 && errno == ENOENT;
-      }
-   }
-
-   return false;
+   return perf->ioctl(fd, DRM_IOCTL_I915_PERF_REMOVE_CONFIG,
+                      &invalid_config_id) < 0 && errno == ENOENT;
 }
 
 bool