From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pg0-f70.google.com (mail-pg0-f70.google.com [74.125.83.70]) by kanga.kvack.org (Postfix) with ESMTP id AE56C6B0038 for ; Thu, 5 Jan 2017 22:26:53 -0500 (EST) Received: by mail-pg0-f70.google.com with SMTP id 5so1531972311pgi.2 for ; Thu, 05 Jan 2017 19:26:53 -0800 (PST) Received: from out0-144.mail.aliyun.com (out0-144.mail.aliyun.com. [140.205.0.144]) by mx.google.com with ESMTP id 129si77893812pgi.256.2017.01.05.19.26.50 for ; Thu, 05 Jan 2017 19:26:52 -0800 (PST) Reply-To: "Hillf Danton" From: "Hillf Danton" References: <20170104111049.15501-1-mgorman@techsingularity.net> <20170104111049.15501-4-mgorman@techsingularity.net> In-Reply-To: <20170104111049.15501-4-mgorman@techsingularity.net> Subject: Re: [PATCH 3/4] mm, page_allocator: Only use per-cpu allocator for irq-safe requests Date: Fri, 06 Jan 2017 11:26:46 +0800 Message-ID: <00ee01d267cc$b61feaa0$225fbfe0$@alibaba-inc.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Content-Language: zh-cn Sender: owner-linux-mm@kvack.org List-ID: To: 'Mel Gorman' , 'Jesper Dangaard Brouer' Cc: 'Linux Kernel' , 'Linux-MM' On Wednesday, January 04, 2017 7:11 PM Mel Gorman wrote: > @@ -2647,9 +2644,8 @@ static struct page *rmqueue_pcplist(struct zone *preferred_zone, > struct list_head *list; > bool cold = ((gfp_flags & __GFP_COLD) != 0); > struct page *page; > - unsigned long flags; > > - local_irq_save(flags); > + preempt_disable(); > pcp = &this_cpu_ptr(zone->pageset)->pcp; > list = &pcp->lists[migratetype]; > page = __rmqueue_pcplist(zone, order, gfp_flags, migratetype, > @@ -2658,7 +2654,7 @@ static struct page *rmqueue_pcplist(struct zone *preferred_zone, > __count_zid_vm_events(PGALLOC, page_zonenum(page), 1 << order); > zone_statistics(preferred_zone, zone, gfp_flags); > } > - local_irq_restore(flags); > + preempt_enable(); > return page; > } > With PREEMPT configured, preempt_enable() adds entry point to schedule(). Is that needed when we try to allocate a page? Hillf -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org