From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761066Ab3BJTcM (ORCPT ); Sun, 10 Feb 2013 14:32:12 -0500 Received: from e23smtp08.au.ibm.com ([202.81.31.141]:53505 "EHLO e23smtp08.au.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1760521Ab3BJTcJ (ORCPT ); Sun, 10 Feb 2013 14:32:09 -0500 Message-ID: <5117F53A.20307@linux.vnet.ibm.com> Date: Mon, 11 Feb 2013 01:00:02 +0530 From: "Srivatsa S. Bhat" User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:15.0) Gecko/20120828 Thunderbird/15.0 MIME-Version: 1.0 To: Oleg Nesterov CC: tglx@linutronix.de, peterz@infradead.org, tj@kernel.org, paulmck@linux.vnet.ibm.com, rusty@rustcorp.com.au, mingo@kernel.org, akpm@linux-foundation.org, namhyung@kernel.org, rostedt@goodmis.org, wangyun@linux.vnet.ibm.com, xiaoguangrong@linux.vnet.ibm.com, rjw@sisk.pl, sbw@mit.edu, fweisbec@gmail.com, linux@arm.linux.org.uk, nikunj@linux.vnet.ibm.com, linux-pm@vger.kernel.org, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linuxppc-dev@lists.ozlabs.org, netdev@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v5 05/45] percpu_rwlock: Make percpu-rwlocks IRQ-safe, optimally References: <20130122073210.13822.50434.stgit@srivatsabhat.in.ibm.com> <20130122073400.13822.52336.stgit@srivatsabhat.in.ibm.com> <20130210184209.GA3041@redhat.com> In-Reply-To: <20130210184209.GA3041@redhat.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit X-Content-Scanned: Fidelis XPS MAILER x-cbid: 13021019-5140-0000-0000-000002BC5F26 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 02/11/2013 12:12 AM, Oleg Nesterov wrote: > only one cosmetic nit... > > On 01/22, Srivatsa S. Bhat wrote: >> >> +#define READER_PRESENT (1UL << 16) >> +#define READER_REFCNT_MASK (READER_PRESENT - 1) >> + >> #define reader_uses_percpu_refcnt(pcpu_rwlock, cpu) \ >> (ACCESS_ONCE(per_cpu(*((pcpu_rwlock)->reader_refcnt), cpu))) >> >> #define reader_nested_percpu(pcpu_rwlock) \ >> - (__this_cpu_read(*((pcpu_rwlock)->reader_refcnt)) > 1) >> + (__this_cpu_read(*((pcpu_rwlock)->reader_refcnt)) & READER_REFCNT_MASK) >> >> #define writer_active(pcpu_rwlock) \ >> (__this_cpu_read(*((pcpu_rwlock)->writer_signal))) > > I think this all can go to lib/percpu-rwlock.c. Nobody needs to know > these implementation details. > Ok, will move them. Regards, Srivatsa S. Bhat From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from e23smtp09.au.ibm.com (e23smtp09.au.ibm.com [202.81.31.142]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "e23smtp09.au.ibm.com", Issuer "GeoTrust SSL CA" (not verified)) by ozlabs.org (Postfix) with ESMTPS id AB3742C0292 for ; Mon, 11 Feb 2013 06:32:05 +1100 (EST) Received: from /spool/local by e23smtp09.au.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Mon, 11 Feb 2013 05:25:14 +1000 Received: from d23relay04.au.ibm.com (d23relay04.au.ibm.com [9.190.234.120]) by d23dlp02.au.ibm.com (Postfix) with ESMTP id 5978F2BB0053 for ; Mon, 11 Feb 2013 06:32:04 +1100 (EST) Received: from d23av02.au.ibm.com (d23av02.au.ibm.com [9.190.235.138]) by d23relay04.au.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id r1AJJtn733685566 for ; Mon, 11 Feb 2013 06:19:55 +1100 Received: from d23av02.au.ibm.com (loopback [127.0.0.1]) by d23av02.au.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id r1AJW2V8010467 for ; Mon, 11 Feb 2013 06:32:04 +1100 Message-ID: <5117F53A.20307@linux.vnet.ibm.com> Date: Mon, 11 Feb 2013 01:00:02 +0530 From: "Srivatsa S. Bhat" MIME-Version: 1.0 To: Oleg Nesterov Subject: Re: [PATCH v5 05/45] percpu_rwlock: Make percpu-rwlocks IRQ-safe, optimally References: <20130122073210.13822.50434.stgit@srivatsabhat.in.ibm.com> <20130122073400.13822.52336.stgit@srivatsabhat.in.ibm.com> <20130210184209.GA3041@redhat.com> In-Reply-To: <20130210184209.GA3041@redhat.com> Content-Type: text/plain; charset=ISO-8859-1 Cc: linux-doc@vger.kernel.org, peterz@infradead.org, fweisbec@gmail.com, mingo@kernel.org, linux-arch@vger.kernel.org, linux@arm.linux.org.uk, xiaoguangrong@linux.vnet.ibm.com, wangyun@linux.vnet.ibm.com, paulmck@linux.vnet.ibm.com, nikunj@linux.vnet.ibm.com, linux-pm@vger.kernel.org, rusty@rustcorp.com.au, rostedt@goodmis.org, rjw@sisk.pl, namhyung@kernel.org, tglx@linutronix.de, linux-arm-kernel@lists.infradead.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, sbw@mit.edu, tj@kernel.org, akpm@linux-foundation.org, linuxppc-dev@lists.ozlabs.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On 02/11/2013 12:12 AM, Oleg Nesterov wrote: > only one cosmetic nit... > > On 01/22, Srivatsa S. Bhat wrote: >> >> +#define READER_PRESENT (1UL << 16) >> +#define READER_REFCNT_MASK (READER_PRESENT - 1) >> + >> #define reader_uses_percpu_refcnt(pcpu_rwlock, cpu) \ >> (ACCESS_ONCE(per_cpu(*((pcpu_rwlock)->reader_refcnt), cpu))) >> >> #define reader_nested_percpu(pcpu_rwlock) \ >> - (__this_cpu_read(*((pcpu_rwlock)->reader_refcnt)) > 1) >> + (__this_cpu_read(*((pcpu_rwlock)->reader_refcnt)) & READER_REFCNT_MASK) >> >> #define writer_active(pcpu_rwlock) \ >> (__this_cpu_read(*((pcpu_rwlock)->writer_signal))) > > I think this all can go to lib/percpu-rwlock.c. Nobody needs to know > these implementation details. > Ok, will move them. Regards, Srivatsa S. Bhat From mboxrd@z Thu Jan 1 00:00:00 1970 From: srivatsa.bhat@linux.vnet.ibm.com (Srivatsa S. Bhat) Date: Mon, 11 Feb 2013 01:00:02 +0530 Subject: [PATCH v5 05/45] percpu_rwlock: Make percpu-rwlocks IRQ-safe, optimally In-Reply-To: <20130210184209.GA3041@redhat.com> References: <20130122073210.13822.50434.stgit@srivatsabhat.in.ibm.com> <20130122073400.13822.52336.stgit@srivatsabhat.in.ibm.com> <20130210184209.GA3041@redhat.com> Message-ID: <5117F53A.20307@linux.vnet.ibm.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 02/11/2013 12:12 AM, Oleg Nesterov wrote: > only one cosmetic nit... > > On 01/22, Srivatsa S. Bhat wrote: >> >> +#define READER_PRESENT (1UL << 16) >> +#define READER_REFCNT_MASK (READER_PRESENT - 1) >> + >> #define reader_uses_percpu_refcnt(pcpu_rwlock, cpu) \ >> (ACCESS_ONCE(per_cpu(*((pcpu_rwlock)->reader_refcnt), cpu))) >> >> #define reader_nested_percpu(pcpu_rwlock) \ >> - (__this_cpu_read(*((pcpu_rwlock)->reader_refcnt)) > 1) >> + (__this_cpu_read(*((pcpu_rwlock)->reader_refcnt)) & READER_REFCNT_MASK) >> >> #define writer_active(pcpu_rwlock) \ >> (__this_cpu_read(*((pcpu_rwlock)->writer_signal))) > > I think this all can go to lib/percpu-rwlock.c. Nobody needs to know > these implementation details. > Ok, will move them. Regards, Srivatsa S. Bhat