From nobody Sat Feb 7 18:00:21 2026 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 E155C14036A for ; Wed, 6 Mar 2024 19:42:11 +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=1709754133; cv=none; b=fRia6DhuvZ5iyvO9ZJBxH9xfHcgaVxitbgLReRoEQSLejJm5deCCkHXtvc/yydHhMiaOQeWjiRNy+0ZnF6gBNT+8IEzYV7XO4gp4uy80yZ67Lktg/Ycvlv5UezcWfn0tVZR16C9OQ22QIWoDOQwUuP5xSyCZ5WSCXm5ENqwc+7E= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709754133; c=relaxed/simple; bh=fz8sVULSokUEtg1apAJP0N1kFWc3PTDlmYeHhou+7FM=; h=Date:From:To:Cc:Subject:Message-ID:MIME-Version:Content-Type: Content-Disposition; b=QhwMXA1FwSWEPcZ5CF/3f4/P23JVOyiRNFDTF/q9GPLHX/6h2th9T6UrOyuIA8b1+ysBQZP0XJ136XI3j8M+viv8oNA/IzOz4DIOzrb3DlNUjniik7vHGZQLvJt0Tj6DMvhQZyQM+UyNBFof0ogZwOrt4xOrcGfDYWtVQhKBiOo= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none 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=a0CcI12l; arc=none smtp.client-ip=170.10.129.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none 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="a0CcI12l" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1709754130; 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; bh=7NzAkrFfDtAG1W4IZ9k3+0Y5QZ/B1qwXKO/PPRafIn0=; b=a0CcI12lmEMeC0/t28O87lqFYlN+bRKmfE+r90OiMs+rtWsIDZmQjZaPxa1TwmrjWsctSi d5AR04fRVxtUnrpJPcC7NhYydZbP7bLJRmS1wZ66PidXMMqAaAHO6+YVLPfYonA4TwTmWt ojQxfgvw7p+BhmrkwaLVbMUWJ8cBbyk= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-135-lhnnuKE-NN-TQ7tU0BGcmw-1; Wed, 06 Mar 2024 14:42:08 -0500 X-MC-Unique: lhnnuKE-NN-TQ7tU0BGcmw-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.rdu2.redhat.com [10.11.54.8]) (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 mimecast-mx02.redhat.com (Postfix) with ESMTPS id 1825185A58C; Wed, 6 Mar 2024 19:42:08 +0000 (UTC) Received: from tpad.localdomain (unknown [10.96.133.5]) by smtp.corp.redhat.com (Postfix) with ESMTPS id D5B1BC041EF; Wed, 6 Mar 2024 19:42:07 +0000 (UTC) Received: by tpad.localdomain (Postfix, from userid 1000) id 3A5B04014ABF9; Wed, 6 Mar 2024 16:41:47 -0300 (-03) Date: Wed, 6 Mar 2024 16:41:47 -0300 From: Marcelo Tosatti To: netdev@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Willem de Bruijn , Jakub Kicinski , Eric Dumazet , Frederic Weisbecker , Valentin Schneider , Paolo Abeni Subject: [PATCH net-next -v4] net/core/dev.c: enable timestamp static key if CPU isolation is configured Message-ID: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Disposition: inline X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.8 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" For systems that use CPU isolation (via nohz_full), creating or destroying a socket with SO_TIMESTAMP, SO_TIMESTAMPNS or SO_TIMESTAMPING with flag SOF_TIMESTAMPING_RX_SOFTWARE will cause a static key to be enabled/disabled. This in turn causes undesired IPIs to isolated CPUs. So enable the static key unconditionally, if CPU isolation is enabled, thus avoiding the IPIs. Signed-off-by: Marcelo Tosatti --- v2: mention SOF_TIMESTAMPING_OPT_TX_SWHW in the commit log (Willem de Bruij= n / Paolo Abeni) v3: SOF_TIMESTAMPING_OPT_TX_SWHW is irrelevant (Willem de Bruijn) v4: additional changelog improvements (Willem de Bruijn) diff --git a/net/core/dev.c b/net/core/dev.c index c588808be77f..15a32f5900e6 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -155,6 +155,7 @@ #include #include #include +#include =20 #include "dev.h" #include "net-sysfs.h" @@ -11851,3 +11852,14 @@ static int __init net_dev_init(void) } =20 subsys_initcall(net_dev_init); + +static int __init net_dev_late_init(void) +{ + /* avoid static key IPIs to isolated CPUs */ + if (housekeeping_enabled(HK_TYPE_MISC)) + net_enable_timestamp(); + + return 0; +} + +late_initcall(net_dev_late_init);