From nobody Fri Sep 12 14:37:02 2025 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id EE2FFC77B7D for ; Mon, 15 May 2023 18:07:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S244849AbjEOSHm (ORCPT ); Mon, 15 May 2023 14:07:42 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39894 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S245020AbjEOSGr (ORCPT ); Mon, 15 May 2023 14:06:47 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A968F659B for ; Mon, 15 May 2023 11:03:48 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1684173827; 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: references:references; bh=BJ6i2oDSiY3YdcuHRj+4qVRIpmZay1wZiVJ33jyxj48=; b=PjSIb+LnT91LxWlqsyWhcdESZ9VlPFgya2xGxH8emPMgoTgXS8CONHs3Xl5vKmaAkaFmCC H+CxZfaEBtEtPMBeFoeKPf34gJGx1iVvHFRRe4gjYhpS0QJinxBIOZ1W3JQp2k9VEEY9dy 7EgEWmQt5Mhd6b9a6h5gOnD8tpRuFdQ= Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-159-HcyxXZ_fOKim-3NV21rk8g-1; Mon, 15 May 2023 14:03:42 -0400 X-MC-Unique: HcyxXZ_fOKim-3NV21rk8g-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.rdu2.redhat.com [10.11.54.4]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 64E8A382C96A; Mon, 15 May 2023 18:03:41 +0000 (UTC) Received: from tpad.localdomain (ovpn-112-4.gru2.redhat.com [10.97.112.4]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 2E3102026D25; Mon, 15 May 2023 18:03:41 +0000 (UTC) Received: by tpad.localdomain (Postfix, from userid 1000) id 65C8A4161E529; Mon, 15 May 2023 15:02:17 -0300 (-03) Message-ID: <20230515180138.591710284@redhat.com> User-Agent: quilt/0.67 Date: Mon, 15 May 2023 15:00:22 -0300 From: Marcelo Tosatti To: Christoph Lameter Cc: Aaron Tomlin , Frederic Weisbecker , Andrew Morton , linux-kernel@vger.kernel.org, linux-mm@kvack.org, Russell King , Huacai Chen , Heiko Carstens , x86@kernel.org, Vlastimil Babka , Michal Hocko , Peter Xu , Marcelo Tosatti Subject: [PATCH v8 07/13] convert this_cpu_cmpxchg users to this_cpu_cmpxchg_local References: <20230515180015.016409657@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.4 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" this_cpu_cmpxchg was modified to atomic version, which=20 can be more costly than non-atomic version. Switch users of this_cpu_cmpxchg to this_cpu_cmpxchg_local (which preserves pre-non-atomic this_cpu_cmpxchg behaviour). Acked-by: Peter Xu Signed-off-by: Marcelo Tosatti --- Index: linux-vmstat-remote/kernel/fork.c =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D --- linux-vmstat-remote.orig/kernel/fork.c +++ linux-vmstat-remote/kernel/fork.c @@ -205,7 +205,7 @@ static bool try_release_thread_stack_to_ unsigned int i; =20 for (i =3D 0; i < NR_CACHED_STACKS; i++) { - if (this_cpu_cmpxchg(cached_stacks[i], NULL, vm) !=3D NULL) + if (this_cpu_cmpxchg_local(cached_stacks[i], NULL, vm) !=3D NULL) continue; return true; } Index: linux-vmstat-remote/kernel/scs.c =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D --- linux-vmstat-remote.orig/kernel/scs.c +++ linux-vmstat-remote/kernel/scs.c @@ -83,7 +83,7 @@ void scs_free(void *s) */ =20 for (i =3D 0; i < NR_CACHED_SCS; i++) - if (this_cpu_cmpxchg(scs_cache[i], 0, s) =3D=3D NULL) + if (this_cpu_cmpxchg_local(scs_cache[i], 0, s) =3D=3D NULL) return; =20 kasan_unpoison_vmalloc(s, SCS_SIZE, KASAN_VMALLOC_PROT_NORMAL);