From patchwork Mon Mar 31 21:30:21 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: James Houghton X-Patchwork-Id: 14034138 Received: from mail-vk1-f202.google.com (mail-vk1-f202.google.com [209.85.221.202]) (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 55EA31B4138 for ; Mon, 31 Mar 2025 21:30:33 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.221.202 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1743456634; cv=none; b=GArwJFyGV+Bi0qbJeviwAna+ZUq4aveA4XZExUs8yDX3cSHFeykiZff6wSQXC162FQMFXv7mK1Vq5qlkGzxAD7xmW5WPgqiL6XFRKsWxqH2EXkys/0HxtQN5jxX35Pvxh090IWdjKH6HmQFscZ9y16+2elFezV0/suo9fm0m+KM= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1743456634; c=relaxed/simple; bh=QVzyFescXVWpRPbHhysiEv6lNMR7Z84PTEV+3tefm0Q=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=qTZRLo8w4EEMvaNzFpy2IixeqfbBrkp2JRX4PRiczmw+AKU+yp1Gi4rgWgH4xazjBK8FTi8a0E5opyPC4xHuhwbxDlsk2Fl+iY21aULk4ruT1uvHKorEN7tmuBUZxEON8E5CA30EfXaNDYeumzKQqw4ozDjej4RxLeEa3DtgO1A= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--jthoughton.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=Fz+Uxl4Y; arc=none smtp.client-ip=209.85.221.202 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--jthoughton.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="Fz+Uxl4Y" Received: by mail-vk1-f202.google.com with SMTP id 71dfb90a1353d-524021ac776so1318469e0c.2 for ; Mon, 31 Mar 2025 14:30:33 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1743456632; x=1744061432; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=42KzVy5OOxbX2nRYaugEY43/RWNtB+bmjk11XtO+x8A=; b=Fz+Uxl4YzmkYqXYrJ/sJbzTzRTBjv7YsGcxg9+0rWaOTL/jX4IsGuxInosI0ACCvLD 5DL0DbKrHF5J479+gC1oIn3zzqszj4oo6JbuNYqFtb9wdyZTORHU3TYFcc5pygfQMLAd tICNtGbfEhk6voOu5iCX0tDP+L4zkorV1zR+0WYiAr1fFFa/qUbSMHWR/nnrDIt7e6Oe KPkl81PAtQsYB7t2MzpOph8gI07eoVx573LHr9fdLlWuu0n704umZOpj0sq/9+I6pWME zTmVKRmndHo5hLjmzo32iihKCGrrVjWp6QAfrG24KfEQtlgz/CRZ/HXHWCJEq5yQw5jb cWLw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1743456632; x=1744061432; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=42KzVy5OOxbX2nRYaugEY43/RWNtB+bmjk11XtO+x8A=; b=l10/jTTclbj785kemqcss5RVgR8gBbgJKITc9xPT0IxC7AQezud4ZSm9rtIutfYx4t wLbiOQ+aMs2XOzvNwoGVh+llEJrivs9pw3pa+m6YK/VFpHcEMlh0mJEjq0qdwzvJN8ny XlERux4wzS5uIrMXK9voLUKuhBFWh/4t7oL5XWF/1T3zvoJi3n7dO/hU7IJSAgEBEVkk kcdy86CBVifrXscwcrtygTXiQO1v2TEgVovcWNX6I6vT60R2MzCpvIyWizvlT2YNYL+P HzlmzPtf/dqISXsZpbPuVCdiaf4/bDOZ25tkXNr3xvKP7mAE0fddoOk77aP/1IQyGuzB TCug== X-Forwarded-Encrypted: i=1; AJvYcCXvJJeYcZypMo55jBkU/6g+I8qCADZglppe6CWZJJ7QdMwz/h2rCC1gS3gyXLR1SEJisg8=@vger.kernel.org X-Gm-Message-State: AOJu0YySS2kNmQXMA1kp4rhMCkY9PJuegqtxrsUb8FvcA+C2TJl5tUtF Dtnu62oWEUa1cVHhwkQbFaWcdPfRZYO5V7pEuZ1oSvtpsrLOok0VEvU8YvUtSmG5HREw9PO6PW9 MJcs2rmXG62bP4HpffQ== X-Google-Smtp-Source: AGHT+IH1S5Pqrxcnd6Psp4+cbC6TmHHG0jz3SYfEB8vHri/pTtyy440S8+fa1zRdaeI5w8d7xLGt0MgU/VoSpbkI X-Received: from vkci17.prod.google.com ([2002:a05:6122:62f1:b0:526:98a:f3d2]) (user=jthoughton job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6122:218b:b0:520:51a4:b81c with SMTP id 71dfb90a1353d-5261d478794mr5909701e0c.6.1743456632248; Mon, 31 Mar 2025 14:30:32 -0700 (PDT) Date: Mon, 31 Mar 2025 21:30:21 +0000 In-Reply-To: <20250331213025.3602082-1-jthoughton@google.com> Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20250331213025.3602082-1-jthoughton@google.com> X-Mailer: git-send-email 2.49.0.472.ge94155a9ec-goog Message-ID: <20250331213025.3602082-2-jthoughton@google.com> Subject: [PATCH v2 1/5] KVM: selftests: Extract guts of THP accessor to standalone sysfs helpers From: James Houghton To: Sean Christopherson , kvm@vger.kernel.org Cc: Maxim Levitsky , Axel Rasmussen , Tejun Heo , Johannes Weiner , mkoutny@suse.com, Yosry Ahmed , Yu Zhao , James Houghton , cgroups@vger.kernel.org, linux-kernel@vger.kernel.org From: Sean Christopherson Extract the guts of thp_configured() and get_trans_hugepagesz() to standalone helpers so that the core logic can be reused for other sysfs files, e.g. to query numa_balancing. Opportunistically assert that the initial fscanf() read at least one byte, and add a comment explaining the second call to fscanf(). Signed-off-by: Sean Christopherson Signed-off-by: Maxim Levitsky --- tools/testing/selftests/kvm/lib/test_util.c | 35 ++++++++++++++------- 1 file changed, 24 insertions(+), 11 deletions(-) diff --git a/tools/testing/selftests/kvm/lib/test_util.c b/tools/testing/selftests/kvm/lib/test_util.c index 8ed0b74ae8373..3dc8538f5d696 100644 --- a/tools/testing/selftests/kvm/lib/test_util.c +++ b/tools/testing/selftests/kvm/lib/test_util.c @@ -132,37 +132,50 @@ void print_skip(const char *fmt, ...) puts(", skipping test"); } -bool thp_configured(void) +static bool test_sysfs_path(const char *path) { - int ret; struct stat statbuf; + int ret; - ret = stat("/sys/kernel/mm/transparent_hugepage", &statbuf); + ret = stat(path, &statbuf); TEST_ASSERT(ret == 0 || (ret == -1 && errno == ENOENT), - "Error in stating /sys/kernel/mm/transparent_hugepage"); + "Error in stat()ing '%s'", path); return ret == 0; } -size_t get_trans_hugepagesz(void) +bool thp_configured(void) +{ + return test_sysfs_path("/sys/kernel/mm/transparent_hugepage"); +} + +static size_t get_sysfs_val(const char *path) { size_t size; FILE *f; int ret; - TEST_ASSERT(thp_configured(), "THP is not configured in host kernel"); - - f = fopen("/sys/kernel/mm/transparent_hugepage/hpage_pmd_size", "r"); - TEST_ASSERT(f != NULL, "Error in opening transparent_hugepage/hpage_pmd_size"); + f = fopen(path, "r"); + TEST_ASSERT(f, "Error opening '%s'", path); ret = fscanf(f, "%ld", &size); + TEST_ASSERT(ret > 0, "Error reading '%s'", path); + + /* Re-scan the input stream to verify the entire file was read. */ ret = fscanf(f, "%ld", &size); - TEST_ASSERT(ret < 1, "Error reading transparent_hugepage/hpage_pmd_size"); - fclose(f); + TEST_ASSERT(ret < 1, "Error reading '%s'", path); + fclose(f); return size; } +size_t get_trans_hugepagesz(void) +{ + TEST_ASSERT(thp_configured(), "THP is not configured in host kernel"); + + return get_sysfs_val("/sys/kernel/mm/transparent_hugepage/hpage_pmd_size"); +} + size_t get_def_hugetlb_pagesz(void) { char buf[64];