From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (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 04FE428FFFB for ; Tue, 31 Mar 2026 04:02:22 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.129.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774929744; cv=none; b=Edzk5slHC3MJEhWoFKRIULpspe8VBZGeCcwRXtMxmp2QxFReeLx8PZThDah6/C+7D8Q5Nec8jpu3s2yQFq/k23kbr8ZMHmsYpFibzYOrg8VxIAIFRczVeCeaD6dekWAok+D8NIn80Y23zFvkK+rZnMZ6ImLzBtXjhB18SZzkv5Y= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774929744; c=relaxed/simple; bh=COp6XN9SPW07LDJbcP5E9OZSYfLuXueUQFuAux/M89I=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=a0vyY5zUXWhPf2XUHTqfkvwueTSSlBCSOgdfirxfu0nwQWL9X9jRWzYtdM+TeC8187PXUAT6XvopFC3Ti4EQTaD7YZqbc92IZzYsqoOmt4WAn2RBo8496vK0+9t64A/8DuZOyOjfoqRvMn701qn+9UpyL88ZFabFnxALh4r4XzQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=M+BQ5PBt; arc=none smtp.client-ip=170.10.129.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="M+BQ5PBt" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1774929741; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=VvrYLvc4bheXY6nHh3gvx/fU9nd8/iSIX4Lotedv4lg=; b=M+BQ5PBtKjO2Q2ENlHPUFSF6mhBoMv7IJBoAqRm8dpTKtmVjzKlHGXrvdthVnzGK5cf/GF S2ilTWG0O/gewOwIp7BUcPRnbstH9VzC2RVaPGlbYs1DV/NLy3f4YztBELD0EBlW788fbo 3wQXaMgi5ms5LzdpYbCMbgHnCrqV9to= Received: from mx-prod-mc-06.mail-002.prod.us-west-2.aws.redhat.com (ec2-35-165-154-97.us-west-2.compute.amazonaws.com [35.165.154.97]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-613-2sKpac99N2CcFOHSra_RFA-1; Tue, 31 Mar 2026 00:02:14 -0400 X-MC-Unique: 2sKpac99N2CcFOHSra_RFA-1 X-Mimecast-MFC-AGG-ID: 2sKpac99N2CcFOHSra_RFA_1774929732 Received: from mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.4]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-06.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id A4405180034E; Tue, 31 Mar 2026 04:02:12 +0000 (UTC) Received: from fedora-laptop-x1.redhat.com (unknown [10.72.112.121]) by mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 892DF30001A1; Tue, 31 Mar 2026 04:02:07 +0000 (UTC) From: Li Wang To: akpm@linux-foundation.org, david@kernel.org, ljs@kernel.org, Liam.Howlett@oracle.com, vbabka@kernel.org, rppt@kernel.org, surenb@google.com, mhocko@suse.com, shuah@kernel.org Cc: linux-mm@kvack.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 2/4] selftests/mm: serialize local_config generation for parallel builds Date: Tue, 31 Mar 2026 12:01:54 +0800 Message-ID: <20260331040156.119158-2-liwang@redhat.com> In-Reply-To: <20260331040156.119158-1-liwang@redhat.com> References: <20260331040156.119158-1-liwang@redhat.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.4 The mm selftests generate both local_config.mk and local_config.h from check_config.sh. With high parallelism (-jN), this can race and lead to incomplete target builds (e.g. only a few binaries get built after 'make -j100', while 'make -j1' builds everything). Switch to a stamp-based dependency: local_config.stamp: check_config.sh ... run check_config.sh ... touch local_config.stamp and make local_config.mk/local_config.h depend on the stamp. This ensures check_config.sh is executed once per update decision and removes the parallel race window. Also hook local_config.stamp into EXTRA_CLEAN. No functional change intended for non-parallel builds. Reported-by: Andrew Morton Signed-off-by: Li Wang --- tools/testing/selftests/mm/Makefile | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/tools/testing/selftests/mm/Makefile b/tools/testing/selftests/mm/Makefile index 3b222cd6a048..78496f705386 100644 --- a/tools/testing/selftests/mm/Makefile +++ b/tools/testing/selftests/mm/Makefile @@ -261,10 +261,14 @@ $(OUTPUT)/migration: LDLIBS += -lnuma $(OUTPUT)/rmap: LDLIBS += -lnuma -local_config.mk local_config.h: check_config.sh - CC="$(CC)" CFLAGS="$(CFLAGS)" ./check_config.sh +local_config.stamp: check_config.sh + $(call msg,CHK,config,$@) + $(Q)CC="$(CC)" CFLAGS="$(CFLAGS)" ./check_config.sh + $(Q)touch $@ -EXTRA_CLEAN += local_config.mk local_config.h +local_config.mk local_config.h: local_config.stamp + +EXTRA_CLEAN += local_config.mk local_config.h local_config.stamp ifeq ($(IOURING_EXTRA_LIBS),) all: warn_missing_liburing -- 2.53.0