From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-179.mta1.migadu.com (out-179.mta1.migadu.com [95.215.58.179]) (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 B81D0237713; Fri, 24 Apr 2026 04:01:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=95.215.58.179 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777003289; cv=none; b=k/d5zdTxC1TlGxOKuNkc9x3WWvixcQJcbWhSOzNZ0JmGfmaGGlQSfP/zbisQWx480hDDlIrcQfqQUY1aiATVZYIxIIT+hsm/pU0TEnPzPgs8TY8ChjiJQGK5RtTlPRKrh3Uk8FTl9eu0FX3cQbyPL6N00caO4fnprW6tNh3deQg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777003289; c=relaxed/simple; bh=wlAlwZ0KZImscE1SdwipDWwqojceWrUohq/ClmcbXAY=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=eqJ7wfn6ZTx4ocvpJvNKom0YWd/DQ6dgxJL6a23aaol2vfRX9uV6UvIiydUv6NvgAZfo5KP7+DpYCY7RWeaspfCywy4vXTQRxh/mcSIZUGcNYhm1y6Yrbu12mfC804DKtlV4ksZz1dUY+Y0x1B6nHpTZl7ssfp0ztf4SX0Q/tfU= 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=oeHyCQPN; arc=none smtp.client-ip=95.215.58.179 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="oeHyCQPN" X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1777003286; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Gr8asudXbZcTLEQoBtpdGFZE+1tjsTEgxDXHfEmUBuk=; b=oeHyCQPN6+7SzNn3zyt6SJZNgJ5tcf7mfOBQNDb1ZmDi/X56dFl5cpn+kLCtEXxwA4x31x tTcK0JLkTWi8s/gOpfklOW8MpGl/JoIh6j8u8MeRtBdpu2GYmpOTVF9Ujdqzh7mSpYFkxP 4qmDHAwU+GLrCHoCPn8itn3iGnIBjRY= From: Li Wang To: akpm@linux-foundation.org, tj@kernel.org, longman@redhat.com, roman.gushchin@linux.dev, hannes@cmpxchg.org, yosry@kernel.org, jiayuan.chen@linux.dev, nphamcs@gmail.com, chengming.zhou@linux.dev, mkoutny@suse.com, shuah@kernel.org Cc: linux-mm@kvack.org, cgroups@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org, Michal Hocko , Muchun Song , Shakeel Butt , Yosry Ahmed Subject: [PATCH v7 1/8] selftests/cgroup: skip test_zswap if zswap is globally disabled Date: Fri, 24 Apr 2026 12:00:52 +0800 Message-ID: <20260424040059.12940-2-li.wang@linux.dev> In-Reply-To: <20260424040059.12940-1-li.wang@linux.dev> References: <20260424040059.12940-1-li.wang@linux.dev> Precedence: bulk X-Mailing-List: linux-kselftest@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT test_zswap currently only checks whether zswap is present by testing /sys/module/zswap. This misses the runtime global state exposed in /sys/module/zswap/parameters/enabled. When zswap is built/loaded but globally disabled, the zswap cgroup selftests run in an invalid environment and may fail spuriously. Check the runtime enabled state before running the tests: - skip if zswap is not configured, - fail if the enabled knob cannot be read, - skip if zswap is globally disabled. Also print a hint in the skip message on how to enable zswap. Signed-off-by: Li Wang Cc: Johannes Weiner Cc: Michal Hocko Cc: Michal Koutný Cc: Muchun Song Cc: Nhat Pham Cc: Tejun Heo Cc: Roman Gushchin Cc: Shakeel Butt Cc: Yosry Ahmed Acked-by: Yosry Ahmed Acked-by: Nhat Pham --- tools/testing/selftests/cgroup/test_zswap.c | 19 +++++++++++++++---- 1 file changed, 15 insertions(+), 4 deletions(-) diff --git a/tools/testing/selftests/cgroup/test_zswap.c b/tools/testing/selftests/cgroup/test_zswap.c index a7bdcdd09d6..a94238a2e04 100644 --- a/tools/testing/selftests/cgroup/test_zswap.c +++ b/tools/testing/selftests/cgroup/test_zswap.c @@ -15,6 +15,9 @@ #include "kselftest.h" #include "cgroup_util.h" +#define PATH_ZSWAP "/sys/module/zswap" +#define PATH_ZSWAP_ENABLED "/sys/module/zswap/parameters/enabled" + static int read_int(const char *path, size_t *value) { FILE *file; @@ -725,9 +728,18 @@ struct zswap_test { }; #undef T -static bool zswap_configured(void) +static void check_zswap_enabled(void) { - return access("/sys/module/zswap", F_OK) == 0; + char value[2]; + + if (access(PATH_ZSWAP, F_OK)) + ksft_exit_skip("zswap isn't configured\n"); + + if (read_text(PATH_ZSWAP_ENABLED, value, sizeof(value)) <= 0) + ksft_exit_fail_msg("Failed to read " PATH_ZSWAP_ENABLED "\n"); + + if (value[0] == 'N') + ksft_exit_skip("zswap is disabled (hint: echo 1 > " PATH_ZSWAP_ENABLED ")\n"); } int main(int argc, char **argv) @@ -740,8 +752,7 @@ int main(int argc, char **argv) if (cg_find_unified_root(root, sizeof(root), NULL)) ksft_exit_skip("cgroup v2 isn't mounted\n"); - if (!zswap_configured()) - ksft_exit_skip("zswap isn't configured\n"); + check_zswap_enabled(); /* * Check that memory controller is available: -- 2.53.0