Return-path: Received: from mx1.redhat.com ([209.132.183.28]:17927 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751922Ab2JCLh7 (ORCPT ); Wed, 3 Oct 2012 07:37:59 -0400 Date: Wed, 3 Oct 2012 13:37:00 +0200 From: Stanislaw Gruszka To: Mel Gorman Cc: Andrew Morton , Pavel Machek , David Rientjes , linux-wireless@vger.kernel.org, johannes.berg@intel.com, wey-yi.w.guy@intel.com, ilw@linux.intel.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: Re: iwl3945: order 5 allocation during ifconfig up; vm problem? Message-ID: <20121003113659.GD2259@redhat.com> (sfid-20121003_133807_885637_EE0C2624) References: <20120909213228.GA5538@elf.ucw.cz> <20120910111113.GA25159@elf.ucw.cz> <20120911162536.bd5171a1.akpm@linux-foundation.org> <20120912101826.GL11266@suse.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <20120912101826.GL11266@suse.de> Sender: linux-wireless-owner@vger.kernel.org List-ID: On Wed, Sep 12, 2012 at 11:18:26AM +0100, Mel Gorman wrote: > On Tue, Sep 11, 2012 at 04:25:36PM -0700, Andrew Morton wrote: > > On Mon, 10 Sep 2012 13:11:13 +0200 > > Pavel Machek wrote: > > > > > On Sun 2012-09-09 15:40:55, David Rientjes wrote: > > > > On Sun, 9 Sep 2012, Pavel Machek wrote: > > > > > > > > > On 3.6.0-rc2+, I tried to turn on the wireless, but got > > > > > > > > > > root@amd:~# ifconfig wlan0 10.0.0.6 up > > > > > SIOCSIFFLAGS: Cannot allocate memory > > > > > SIOCSIFFLAGS: Cannot allocate memory > > > > > root@amd:~# > > > > > > > > > > It looks like it uses "a bit too big" allocations to allocate > > > > > firmware...? Order five allocation.... > > > > > > > > > > Hmm... then I did "echo 3 > /proc/sys/vm/drop_caches" and now the > > > > > network works. Is it VM problem that it failed to allocate memory when > > > > > it was freeable? > > > > > > > > > > > > > Do you have CONFIG_COMPACTION enabled? > > > > > > Yes: > > > > > > pavel@amd:/data/l/linux-good$ zgrep CONFIG_COMPACTION /proc/config.gz > > > CONFIG_COMPACTION=y > > > > Asking for a 256k allocation is pretty crazy - this is an operating > > system kernel, not a userspace application. > > > > I'm wondering if this is due to a recent change, but I'm having trouble > > working out where the allocation call site is. > > It may be indirectly due to a recent change and this was somewhat > deliberate. Order-5 is larger than PAGE_ALLOC_COSTLY_ORDER and I doubt > __GFP_REPEAT was set so it is treated as something that can fail in > preference to aggressively reclaiming pages to satisfy the allocation. In > older kernels with lumpy reclaim and an aggressive kswapd it would have > probably succeeded but now it errs on the side of failing early instead > assuming that the caller can recover. Drivers that depend on order-5 > allocations to succeed for correct operation are somewhat frowned upon. So, can this problem be solved like on below patch, or I should rather split firmware loading into chunks similar like was already iwlwifi did? diff --git a/drivers/net/wireless/iwlegacy/common.h b/drivers/net/wireless/iwlegacy/common.h index 5f50177..1b58222 100644 --- a/drivers/net/wireless/iwlegacy/common.h +++ b/drivers/net/wireless/iwlegacy/common.h @@ -2247,7 +2247,7 @@ il_alloc_fw_desc(struct pci_dev *pci_dev, struct fw_desc *desc) desc->v_addr = dma_alloc_coherent(&pci_dev->dev, desc->len, &desc->p_addr, - GFP_KERNEL); + GFP_KERNEL | __GFP_REPEAT); return (desc->v_addr != NULL) ? 0 : -ENOMEM; }