From patchwork Wed Nov 16 07:23:48 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hou Tao X-Patchwork-Id: 13044440 X-Patchwork-Delegate: bpf@iogearbox.net Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B06CBC4332F for ; Wed, 16 Nov 2022 06:58:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230522AbiKPG6S (ORCPT ); Wed, 16 Nov 2022 01:58:18 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33276 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231622AbiKPG6R (ORCPT ); Wed, 16 Nov 2022 01:58:17 -0500 Received: from dggsgout11.his.huawei.com (dggsgout11.his.huawei.com [45.249.212.51]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D19E0BC15 for ; Tue, 15 Nov 2022 22:58:16 -0800 (PST) Received: from mail02.huawei.com (unknown [172.30.67.153]) by dggsgout11.his.huawei.com (SkyGuard) with ESMTP id 4NBv5H16jzz4f3tpW for ; Wed, 16 Nov 2022 14:58:11 +0800 (CST) Received: from huaweicloud.com (unknown [10.175.124.27]) by APP4 (Coremail) with SMTP id gCh0CgDH69gBinRjrfhyAg--.6637S5; Wed, 16 Nov 2022 14:58:14 +0800 (CST) From: Hou Tao To: bpf@vger.kernel.org, Andrii Nakryiko , David Vernet Cc: Martin KaFai Lau , Song Liu , Hao Luo , Yonghong Song , Alexei Starovoitov , Daniel Borkmann , KP Singh , Stanislav Fomichev , Jiri Olsa , John Fastabend , houtao1@huawei.com Subject: [PATCH bpf v2 1/4] libbpf: Use page size as max_entries when probing ring buffer map Date: Wed, 16 Nov 2022 15:23:48 +0800 Message-Id: <20221116072351.1168938-2-houtao@huaweicloud.com> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20221116072351.1168938-1-houtao@huaweicloud.com> References: <20221116072351.1168938-1-houtao@huaweicloud.com> MIME-Version: 1.0 X-CM-TRANSID: gCh0CgDH69gBinRjrfhyAg--.6637S5 X-Coremail-Antispam: 1UD129KBjvdXoWrZFW8AFykJFW8XFW8WF45Wrg_yoWkGFgE93 97XFWxXryfWFs2vw1rJrZ09rs7Gw1rGF4rWr45tr98Ar4Yk3WkJF4xuF9rXFWSvw1kKryx WrZ7Xr429r13WjkaLaAFLSUrUUUUUb8apTn2vfkv8UJUUUU8Yxn0WfASr-VFAUDa7-sFnT 9fnUUIcSsGvfJTRUUUbfxYFVCjjxCrM7AC8VAFwI0_Wr0E3s1l1xkIjI8I6I8E6xAIw20E Y4v20xvaj40_Wr0E3s1l1IIY67AEw4v_Jr0_Jr4l82xGYIkIc2x26280x7IE14v26r18M2 8IrcIa0xkI8VCY1x0267AKxVW8JVW5JwA2ocxC64kIII0Yj41l84x0c7CEw4AK67xGY2AK 021l84ACjcxK6xIIjxv20xvE14v26w1j6s0DM28EF7xvwVC0I7IYx2IY6xkF7I0E14v26r 4UJVWxJr1l84ACjcxK6I8E87Iv67AKxVW0oVCq3wA2z4x0Y4vEx4A2jsIEc7CjxVAFwI0_ GcCE3s1le2I262IYc4CY6c8Ij28IcVAaY2xG8wAqx4xG64xvF2IEw4CE5I8CrVC2j2WlYx 0E2Ix0cI8IcVAFwI0_Jr0_Jr4lYx0Ex4A2jsIE14v26r1j6r4UMcvjeVCFs4IE7xkEbVWU JVW8JwACjcxG0xvY0x0EwIxGrwACI402YVCY1x02628vn2kIc2xKxwCF04k20xvY0x0EwI xGrwCFx2IqxVCFs4IE7xkEbVWUJVW8JwC20s026c02F40E14v26r1j6r18MI8I3I0E7480 Y4vE14v26r106r1rMI8E67AF67kF1VAFwI0_Jw0_GFylIxkGc2Ij64vIr41lIxAIcVC0I7 IYx2IY67AKxVWUJVWUCwCI42IY6xIIjxv20xvEc7CjxVAFwI0_Gr0_Cr1lIxAIcVCF04k2 6cxKx2IYs7xG6r1j6r1xMIIF0xvEx4A2jsIE14v26r1j6r4UMIIF0xvEx4A2jsIEc7CjxV AFwI0_Gr0_Gr1UYxBIdaVFxhVjvjDU0xZFpf9x07jn9N3UUUUU= X-CM-SenderInfo: xkrx3t3r6k3tpzhluzxrxghudrp/ X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net From: Hou Tao Using page size as max_entries when probing ring buffer map, else the probe may fail on host with 64KB page size (e.g., an ARM64 host). After the fix, the output of "bpftool feature" on above host will be correct. Before : eBPF map_type ringbuf is NOT available eBPF map_type user_ringbuf is NOT available After : eBPF map_type ringbuf is available eBPF map_type user_ringbuf is available Signed-off-by: Hou Tao --- tools/lib/bpf/libbpf_probes.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/lib/bpf/libbpf_probes.c b/tools/lib/bpf/libbpf_probes.c index f3a8e8e74eb8..d504d96adc83 100644 --- a/tools/lib/bpf/libbpf_probes.c +++ b/tools/lib/bpf/libbpf_probes.c @@ -234,7 +234,7 @@ static int probe_map_create(enum bpf_map_type map_type) case BPF_MAP_TYPE_USER_RINGBUF: key_size = 0; value_size = 0; - max_entries = 4096; + max_entries = sysconf(_SC_PAGE_SIZE); break; case BPF_MAP_TYPE_STRUCT_OPS: /* we'll get -ENOTSUPP for invalid BTF type ID for struct_ops */