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[23.128.96.18]) by mx.google.com with ESMTP id 4si4633084ejr.126.2021.06.11.06.14.10; Fri, 11 Jun 2021 06:14:34 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; dkim=temperror (no key for signature) header.i=@szeredi.hu header.s=google header.b=nuOQjiPW; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231759AbhFKNNx (ORCPT + 99 others); Fri, 11 Jun 2021 09:13:53 -0400 Received: from mail-ua1-f53.google.com ([209.85.222.53]:36764 "EHLO mail-ua1-f53.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230382AbhFKNNw (ORCPT ); Fri, 11 Jun 2021 09:13:52 -0400 Received: by mail-ua1-f53.google.com with SMTP id p9so2554596uar.3 for ; Fri, 11 Jun 2021 06:11:54 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=szeredi.hu; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=+ULZVsXvT2HWlmGZYxfKYKgrZf9KLwBei15Frc9B25c=; b=nuOQjiPW7qizfzMdFAja/sKz6cdXjNB7Mn+HG80ezLRvTPTrXB5lxVMrVhybLt2m1b 1MZM2J0iFj7Q6cawbgc95NUqlyLgzp0cgELPpnqEyJWL8YiUghB9oHHvEsKXTLvWDxLP JbrnAujJc5JHU0pKYSWXL5p6nmY44LrFjvsWU= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=+ULZVsXvT2HWlmGZYxfKYKgrZf9KLwBei15Frc9B25c=; b=e5AYxL0oCPBo6mXBB0DSaaZ4C7WunNoVshl/ZlKcr3qTCCnP0RA0rEBHulH3hDogM7 dT+hPhTVkm8tdtQjdCjx1DSXnTm8ZhD3ncVkzU099EAbNQUEhrH7gvqKnP33J3XS/Bzs VmLBxzN4kxn9/9ch2ctiFVrezRwtoMJVl1ChHoRMjudMslmHqXMkQanZ8InH4XUAF595 GCodxOKjSgxmriAPw6YTpXIluahIiA+jufaXr7iuBm55416PofuEwTouJH+zSEl/cCck UcFKGed+imk/DlDonkgWTcU7qUc5U8z8k04Fb87q4lBljTwlQMvqo0n/gg3CkJN09QXU WHgQ== X-Gm-Message-State: AOAM531uemMVpUIy9UcLIvYKCWkBIwXzBSGkQpZFAbuznBD+D6B3m8Ow k/NsB3i30q8x00zhIqETUMTi63zUied3lDRCd3CaKA== X-Received: by 2002:ab0:2690:: with SMTP id t16mr2902103uao.9.1623417054643; Fri, 11 Jun 2021 06:10:54 -0700 (PDT) MIME-Version: 1.0 References: <162322846765.361452.17051755721944717990.stgit@web.messagingengine.com> <162322865230.361452.5882168567975703664.stgit@web.messagingengine.com> In-Reply-To: <162322865230.361452.5882168567975703664.stgit@web.messagingengine.com> From: Miklos Szeredi Date: Fri, 11 Jun 2021 15:10:44 +0200 Message-ID: Subject: Re: [PATCH v6 4/7] kernfs: switch kernfs to use an rwsem To: Ian Kent Cc: Greg Kroah-Hartman , Tejun Heo , Eric Sandeen , Fox Chen , Brice Goglin , Al Viro , Rick Lindsley , David Howells , Marcelo Tosatti , "Eric W. Biederman" , Carlos Maiolino , linux-fsdevel , Kernel Mailing List Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 9 Jun 2021 at 10:51, Ian Kent wrote: > > The kernfs global lock restricts the ability to perform kernfs node > lookup operations in parallel during path walks. > > Change the kernfs mutex to an rwsem so that, when opportunity arises, > node searches can be done in parallel with path walk lookups. > > Signed-off-by: Ian Kent Reviewed-by: Miklos Szeredi