From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 78AF95505F6 for ; Tue, 8 Sep 2026 13:12:14 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788873139; cv=none; b=XqqV5OeNK9VV+SYYGYtmhIPOrMlie/x9PBybZtjfXEHvxfsCz3UNKOCIX1FdKoSMrO/4rMB79a//BBhANBEAj4DjZFAA80+v47LQJVl7iGyZHSwkDzT68dWqZTbhw4kISa3cVsh8kVEfBPwYEcojUIYh9LApo/hqgEK+55b8A1I= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788873139; c=relaxed/simple; bh=6sQiPgnwqYRfCPGfgkyhNqjlXnXl6StckUi9QNb2mbo=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=iTqddBQAAgPKVcfT6+xkbEwi9/3Rxki2oWS3YM/TuAuNrA1Lrt9+ZYya6/DaCP+HF8Sn7RXq7fWTuMNUI3vOpdDyYdaKBSmJk5KeSXUEpWndhQ40fNs7MBTgmfCjG2/2p45CWFAH+K5SUxccGedTGWpK+Xn/5nNP+N1Rs3atolE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=AAAO9H9b; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="AAAO9H9b" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 472B71F00ACF; Tue, 8 Sep 2026 13:12:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1788873132; bh=Y4JhlJeGqTiY+06VSZp5P8/MZHw/WybjDzFnYG70VhE=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=AAAO9H9bgColpJHO5kqwYsSa0XR8zvxrBhIPosHwXQQzIg0FpYD2tvZN6Atl6SRiu 0nqHkoQ08LIhAe2JhNUyjZX2aRDNWobcmT4xVAQGZdaiplH0rG7y1q4/CJenZcI7dG Oqsi5kMi8OJ//hVPaZzjK8mn9XRWaTaKjf8HfVg/Wzrm19D1rnbXkaQISaxARLtBIJ MdK1MBg3DudTv5cJoZ7Wh9PbH1faW8x1WX36FWV/7m9ZTif45BL8QXkpv2JB8uuVv1 +DO3rczTsfy1kXWAzhDIJiPtBS59WGEf3CF3a5Ske/ehjFIgTSWdRhzop9tbeC47Rt mLQof9/q5mT8A== From: Sasha Levin To: stable@vger.kernel.org Cc: Jiri Olsa , Andrii Nakryiko , Sasha Levin Subject: [PATCH 6.18.y 3/5] bpf: Factor stackid_new_bucket from __bpf_get_stackid Date: Tue, 8 Sep 2026 09:12:07 -0400 Message-ID: <20260908131209.2236373-3-sashal@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260908131209.2236373-1-sashal@kernel.org> References: <2026090347-bodacious-studio-93ee@gregkh> <20260908131209.2236373-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Jiri Olsa [ Upstream commit bb4e6f4e1b68fe60c04ca04c564c6624e837dbf4 ] The new stackid_new_bucket allocates the new bucket and initializes it with the trace data. Signed-off-by: Jiri Olsa Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20260803210149.296496-4-jolsa@kernel.org Stable-dep-of: 15f1bd857466 ("bpf: Disable preemption in bpf_get_stackid") Signed-off-by: Sasha Levin --- kernel/bpf/stackmap.c | 48 +++++++++++++++++++++++++++---------------- 1 file changed, 30 insertions(+), 18 deletions(-) diff --git a/kernel/bpf/stackmap.c b/kernel/bpf/stackmap.c index b3661d6f18676..cd3b91a726336 100644 --- a/kernel/bpf/stackmap.c +++ b/kernel/bpf/stackmap.c @@ -301,31 +301,52 @@ static int stackid_fastpath(struct stackid *stackid, struct bpf_map *map, return -ENOENT; } +static struct stack_map_bucket * +stackid_new_bucket(struct stackid *stackid, struct bpf_map *map) +{ + struct bpf_stack_map *smap = container_of(map, struct bpf_stack_map, map); + struct bpf_stack_build_id *id_offs; + struct stack_map_bucket *bucket; + u32 i; + + bucket = (struct stack_map_bucket *) pcpu_freelist_pop(&smap->freelist); + if (unlikely(!bucket)) + return NULL; + + if (stack_map_use_build_id(map)) { + id_offs = (struct bpf_stack_build_id *)bucket->data; + for (i = 0; i < stackid->nr; i++) + id_offs[i].ip = stackid->ips[i]; + } else { + memcpy(bucket->data, stackid->ips, stackid->len); + } + + bucket->hash = stackid->hash; + bucket->nr = stackid->nr; + return bucket; +} + static long __bpf_get_stackid(struct stackid *stackid, struct bpf_map *map, struct perf_callchain_entry *trace, u64 flags) { struct bpf_stack_map *smap = container_of(map, struct bpf_stack_map, map); struct stack_map_bucket *new_bucket, *old_bucket; bool user = flags & BPF_F_USER_STACK; - u32 trace_len, i; + u32 trace_len; int err; err = stackid_fastpath(stackid, map, trace, flags); if (err != -ENOENT) return err; + new_bucket = stackid_new_bucket(stackid, map); + if (!new_bucket) + return -ENOMEM; + if (stack_map_use_build_id(map)) { struct bpf_stack_build_id *id_offs; - /* for build_id+offset, pop a bucket before slow cmp */ - new_bucket = (struct stack_map_bucket *) - pcpu_freelist_pop(&smap->freelist); - if (unlikely(!new_bucket)) - return -ENOMEM; - new_bucket->nr = stackid->nr; id_offs = (struct bpf_stack_build_id *)new_bucket->data; - for (i = 0; i < stackid->nr; i++) - id_offs[i].ip = stackid->ips[i]; stack_map_get_build_id_offset(id_offs, stackid->nr, user, false /* !may_fault */); trace_len = stackid->nr * sizeof(struct bpf_stack_build_id); if (stackid->hash_matches && stackid->bucket->nr == stackid->nr && @@ -337,17 +358,8 @@ static long __bpf_get_stackid(struct stackid *stackid, struct bpf_map *map, pcpu_freelist_push(&smap->freelist, &new_bucket->fnode); return -EEXIST; } - } else { - new_bucket = (struct stack_map_bucket *) - pcpu_freelist_pop(&smap->freelist); - if (unlikely(!new_bucket)) - return -ENOMEM; - memcpy(new_bucket->data, stackid->ips, stackid->len); } - new_bucket->hash = stackid->hash; - new_bucket->nr = stackid->nr; - old_bucket = xchg(&smap->buckets[stackid->id], new_bucket); if (old_bucket) pcpu_freelist_push(&smap->freelist, &old_bucket->fnode); -- 2.53.0