From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (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 40D8A3A1692 for ; Fri, 10 Apr 2026 07:28:11 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.133.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775806092; cv=none; b=MPdM7ivk4c91DjeHf8QeXZDwahntq290b92L/C7v7YTSuFViONYe2Nb0CWj84qbr8yUeRfp/yXGzLIGmq05Hla6738+q0b8VH35wmw2kX/dxBYosEdrWCrnew8Jwmod4PTahRis5IYpVbP6c6CoxB2JA042OMdUlBu36tU04obY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775806092; c=relaxed/simple; bh=KG3SX1YChb1ct+6zF6NR9IEGP7iDFBUiJqLUoPURypA=; h=From:To:Cc:Subject:In-Reply-To:References:Date:Message-ID: MIME-Version:Content-Type; b=lvpTiBp+LULisUZY/HGldi+bpEfspHHUO+Un0ts6Lfl6aUnAr5f7wPd8gcWE/vs6cy7DOBwkVy/gcv8wmViYAZZb0PZNs3FB5q5HEOSyb7qsJXFlqXxCXY2Z5GrdUQe/gjaXBaFpf/npM3pMRb6kgkgXrPJb/2OiG3LMFB/TcX4= 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=Erww+OFR; arc=none smtp.client-ip=170.10.133.124 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="Erww+OFR" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1775806090; 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: in-reply-to:in-reply-to:references:references; bh=wAD6x7ZHet8MHOjXGQZEBEeNflFtc66dfEcX7Gn2HpI=; b=Erww+OFRYV8yTl1imrZ0F/XO4uB8kdxE4B9K6myRmzduMAMnDEFls/3vqRSZdyfnTL1DNZ Br17aomkePS3OmLnxoUp/HL8U4hSRez/l/OVSoe2//0G7OH4AZuk5vYrGSMeX568uq2Ezw mrXJpFqRR9bFOhCrFljQ+Ed/Pp59YRE= 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-194-brPOQarDOye-zE5p7smMSA-1; Fri, 10 Apr 2026 03:28:05 -0400 X-MC-Unique: brPOQarDOye-zE5p7smMSA-1 X-Mimecast-MFC-AGG-ID: brPOQarDOye-zE5p7smMSA_1775806084 Received: from mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.12]) (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 D85221800365; Fri, 10 Apr 2026 07:28:03 +0000 (UTC) Received: from fweimer-oldenburg.csb.redhat.com (unknown [10.2.16.5]) by mx-prod-int-03.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id BD45219560AB; Fri, 10 Apr 2026 07:28:01 +0000 (UTC) From: Florian Weimer To: "H.J. Lu" Cc: GNU C Library , Alexey Dobriyan , linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, linux-api@vger.kernel.org Subject: Re: Avoid reading /sys/kernel/mm/transparent_hugepage/? In-Reply-To: (H. J. Lu's message of "Fri, 10 Apr 2026 13:50:35 +0800") References: Date: Fri, 10 Apr 2026 09:27:59 +0200 Message-ID: User-Agent: Gnus/5.13 (Gnus v5.13) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain X-Scanned-By: MIMEDefang 3.0 on 10.30.177.12 * H. J. Lu: > To enable THP segment load, ld.so opens and reads 2 files under > /sys/kernel/mm/transparent_hugepage/. This requires mounting > /sys and is expensive. Is it possible to put such info in vDSO? Alexey Dobriyan proposed adding AT_PAGE_SHIFT_LIST to the auxiliary vector a while back, but I don't know the status of that. Thanks, Florian