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X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 13 Jan 2026 03:11:29.1937 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 03dce0cd-1559-4e41-f319-08de5251720a X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=3dd8961f-e488-4e60-8e11-a82d994e183d;Ip=[165.204.84.17];Helo=[satlexmb07.amd.com] X-MS-Exchange-CrossTenant-AuthSource: BN1PEPF00004687.namprd05.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: MW4PR12MB5644 Hello Tycho, On 1/9/2026 10:14 PM, Tycho Andersen wrote: > @@ -43,19 +43,20 @@ static void check_slab_cache_iter(struct lock_contention *con) > con->btf = btf__load_vmlinux_btf(); > if (con->btf == NULL) { > pr_debug("BTF loading failed: %s\n", strerror(errno)); > - return; > + return -errno; > } > > ret = btf__find_by_name_kind(con->btf, "bpf_iter__kmem_cache", BTF_KIND_STRUCT); > if (ret < 0) { > bpf_program__set_autoload(skel->progs.slab_cache_iter, false); > pr_debug("slab cache iterator is not available: %d\n", ret); > - return; > + return ret; > } > > has_slab_iter = true; > > bpf_map__set_max_entries(skel->maps.slab_caches, con->map_nr_entries); > + return 0; > } > > static void run_slab_cache_iter(void) > @@ -301,7 +302,8 @@ int lock_contention_prepare(struct lock_contention *con) > skel->rodata->use_cgroup_v2 = 1; > } > > - check_slab_cache_iter(con); > + if (check_slab_cache_iter(con) < 0) > + return -1; > > if (con->filters->nr_slabs && has_slab_iter) { nit. Now that lock_contention_prepare() bails out when check_slab_cache_iter() fails, we no longer need the "has_slab_iter" global indicator. Both this, and run_slab_cache_iter() that depend on "has_slab_iter" will only run if check_slab_cache_iter() succeeded and the global indicator will be true in both those cases. Can be separate follow-up cleanup. > skel->rodata->has_slab = 1; > > base-commit: 5572ad8fddecd4a0db19801262072ff5916b7589 -- Thanks and Regards, Prateek