Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757227AbZDVODO (ORCPT ); Wed, 22 Apr 2009 10:03:14 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757073AbZDVOCs (ORCPT ); Wed, 22 Apr 2009 10:02:48 -0400 Received: from e35.co.us.ibm.com ([32.97.110.153]:51944 "EHLO e35.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757249AbZDVOCr (ORCPT ); Wed, 22 Apr 2009 10:02:47 -0400 From: Stefan Roscher To: Roland Dreier Subject: Re: [PATCH 1/3] IB/ehca: Replace vmalloc with kmalloc Date: Wed, 22 Apr 2009 16:02:28 +0200 User-Agent: KMail/1.9.9 Cc: "LinuxPPC-Dev" , LKML , "OF-EWG" , Roland Dreier , fenkes@de.ibm.com, raisch@de.ibm.com, alexschm@de.ibm.com, stefan.roscher@de.ibm.com, hnguyen@de.ibm.com References: <200904211716.45245.ossrosch@linux.vnet.ibm.com> In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200904221602.29028.ossrosch@linux.vnet.ibm.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2495 Lines: 78 In case of large queue pairs there is the possibillity of allocation failures due to memory fragmentationo with kmalloc().To ensure the memory is allocated even if kmalloc() can not find chunks which are big enough, we try to allocate the memory with vmalloc(). Signed-off-by: Stefan Roscher --- On Tuesday 21 April 2009 07:34:30 pm Roland Dreier wrote: > > + queue->queue_pages = kmalloc(nr_of_pages * sizeof(void *), GFP_KERNEL); > > How big might this buffer be? Any chance of allocation failure due to > memory fragmentation? > > - R. Hey Roland, yes you are right and here is the patch to circumvent the described problem. It will apply on top of the patchset. regards Stefan drivers/infiniband/hw/ehca/ipz_pt_fn.c | 17 +++++++++++++---- 1 files changed, 13 insertions(+), 4 deletions(-) diff --git a/drivers/infiniband/hw/ehca/ipz_pt_fn.c b/drivers/infiniband/hw/ehca/ipz_pt_fn.c index a260559..1227c59 100644 --- a/drivers/infiniband/hw/ehca/ipz_pt_fn.c +++ b/drivers/infiniband/hw/ehca/ipz_pt_fn.c @@ -222,8 +222,11 @@ int ipz_queue_ctor(struct ehca_pd *pd, struct ipz_queue *queue, /* allocate queue page pointers */ queue->queue_pages = kmalloc(nr_of_pages * sizeof(void *), GFP_KERNEL); if (!queue->queue_pages) { - ehca_gen_err("Couldn't allocate queue page list"); - return 0; + queue->queue_pages = vmalloc(nr_of_pages * sizeof(void *)); + if (!queue->queue_pages) { + ehca_gen_err("Couldn't allocate queue page list"); + return 0; + } } memset(queue->queue_pages, 0, nr_of_pages * sizeof(void *)); @@ -240,7 +243,10 @@ int ipz_queue_ctor(struct ehca_pd *pd, struct ipz_queue *queue, ipz_queue_ctor_exit0: ehca_gen_err("Couldn't alloc pages queue=%p " "nr_of_pages=%x", queue, nr_of_pages); - kfree(queue->queue_pages); + if (is_vmalloc_addr(queue->queue_pages)) + vfree(queue->queue_pages); + else + kfree(queue->queue_pages); return 0; } @@ -262,7 +268,10 @@ int ipz_queue_dtor(struct ehca_pd *pd, struct ipz_queue *queue) free_page((unsigned long)queue->queue_pages[i]); } - kfree(queue->queue_pages); + if (is_vmalloc_addr(queue->queue_pages)) + vfree(queue->queue_pages); + else + kfree(queue->queue_pages); return 1; } -- 1.5.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/