From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mta1.migadu.com (out-62.mta1.migadu.com [95.215.58.62]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 2CECC23EA94 for ; Tue, 25 Aug 2026 05:17:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=95.215.58.62 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787635045; cv=none; b=ADqbejiq3Zxh8bv9Z2IcOJvCcUngzY9dIiHDVDrSTU/bOC3qpVV3AKHudpFnGR5hTDiIchQWJDlD/qwANQPQJz5K6BY5qbBf64flSf1an6KcMIsRFIXr4yTiH+kQtGHx0xDAGbQlXVtefiugm+Hz0iGqTEjLXM3W1PTemi+5g18= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787635045; c=relaxed/simple; bh=9PxiUEhNs0QEoZNWcrStmTbnn5tMM7qCOJzneWfUU0s=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=sQUWlJ5XCi+KaqTqcQMV+wOf3i9LxT7K0SwR/o71d0R+n08tXpWKHVt79G+7Qsn+EUfoUti1hm9hkKFZPNA4usNDM6eC+eC2RjiIeBoO7JuZGP09s4yruWRcpVLu5lNn0WGr5+rzoXSXRkWf8hHg63E5rtl8B6Hu7vJsfFg6pmk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=KEkwVraW; arc=none smtp.client-ip=95.215.58.62 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="KEkwVraW" X-Envelope-To: bpf@vger.kernel.org DKIM-Signature: a=rsa-sha256; bh=9PxiUEhNs0QEoZNWcrStmTbnn5tMM7qCOJzneWfUU0s=; c=simple/simple; d=linux.dev; h=from:to:subject:date:message-id:mime-version:content-type; s=key1; t=1787635042; v=1; x=1788239842; b=KEkwVraWIlw1eXqCriqluIhQUgA4vaYiM27sMCMWPsYFa2KRcdwYvqFG9K67p8mPrlj3LN1V wrv4wp3fzTGQ13E4LYJcO2dO0CRouMzQ4cnCRYeXlSw/FuykwJCI5s6SXlZwIJlf1MPRn7fnnb1 J+MXPBKYapPJsOMSzs4SzRNM= X-Envelope-To: bpf@vger.kernel.org Received: from [10.22.64.46] (122.11.166.8) by smtp.migadu.com with ESMTPS id f51d73458007ef9f; Tue, 25 Aug 2026 05:17:22 +0000 X-Mizu-Trace-ID: f51d73458007ef9f X-Migadu-Flow: FLOW_OUT Message-ID: Date: Tue, 25 Aug 2026 13:17:10 +0800 Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH bpf-next v2] selftests/bpf: Avoid flaky resize value test for percpu data To: Andrii Nakryiko Cc: bot+bpf-ci@kernel.org, bpf@vger.kernel.org, ast@kernel.org, daniel@iogearbox.net, andrii@kernel.org, eddyz87@gmail.com, memxor@gmail.com, martin.lau@linux.dev, song@kernel.org, yonghong.song@linux.dev, jolsa@kernel.org, emil@etsalapatis.com, ihor.solodrai@linux.dev, shuah@kernel.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org, martin.lau@kernel.org, clm@meta.com References: <20260818153202.90714-1-leon.hwang@linux.dev> <948e7ff41f942519880f9789faf6ca8ed9d0e2cf42eab5b9e1567ead5367b830@mail.kernel.org> <90bbc900-21cd-4dfb-a058-13930378052f@linux.dev> Content-Language: en-US From: Leon Hwang In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit On 25/8/26 04:04, Andrii Nakryiko wrote: > On Sun, Aug 23, 2026 at 10:02 PM Leon Hwang wrote: [...] >>> >> It is to verify the mmap change in libbpf's bpf_map_mmap_resize() for >> percpu data map, like those subtests in global_map_resize.c. >> > > this didn't explain much, but I think what you are trying to say is > that this won't work for PERCPU arrays with PAGE_SIZE=64KB, because > PERCPU value is limited to 32KB today, is that right? > Right. Limiting PAGE_SIZE=4KB is to avoid the test_global_percpu_data__load() failure due to PERCPU value 32KB limit when PAGE_SIZE is 64KB. > > so maybe actually model that in the test itself, expect -E2BIG if > PAGE_SIZE > 32KB or something, and otherwise check the resize? > How about skipping test_percpu_data_on_cpus() when test_global_percpu_data__load() returns -E2BIG? Because bpf_map__set_value_size() has already been verified before calling test_global_percpu_data__load(). Afterward, it's unnecessary to check PAGE_SIZE value. Thanks, Leon