From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pa0-f44.google.com (mail-pa0-f44.google.com [209.85.220.44]) by kanga.kvack.org (Postfix) with ESMTP id 1484D6B007D for ; Wed, 25 Sep 2013 19:23:40 -0400 (EDT) Received: by mail-pa0-f44.google.com with SMTP id lf10so473923pab.17 for ; Wed, 25 Sep 2013 16:23:39 -0700 (PDT) Received: from /spool/local by e28smtp01.in.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Thu, 26 Sep 2013 04:53:26 +0530 Received: from d28relay04.in.ibm.com (d28relay04.in.ibm.com [9.184.220.61]) by d28dlp02.in.ibm.com (Postfix) with ESMTP id 16326394004D for ; Thu, 26 Sep 2013 04:53:09 +0530 (IST) Received: from d28av04.in.ibm.com (d28av04.in.ibm.com [9.184.220.66]) by d28relay04.in.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id r8PNNLnW41680946 for ; Thu, 26 Sep 2013 04:53:21 +0530 Received: from d28av04.in.ibm.com (localhost [127.0.0.1]) by d28av04.in.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id r8PNNMoD023173 for ; Thu, 26 Sep 2013 04:53:23 +0530 From: "Srivatsa S. Bhat" Subject: [RFC PATCH v4 24/40] mm: Drop some very expensive sorted-buddy related checks under DEBUG_PAGEALLOC Date: Thu, 26 Sep 2013 04:49:17 +0530 Message-ID: <20130925231915.26184.87083.stgit@srivatsabhat.in.ibm.com> In-Reply-To: <20130925231250.26184.31438.stgit@srivatsabhat.in.ibm.com> References: <20130925231250.26184.31438.stgit@srivatsabhat.in.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: akpm@linux-foundation.org, mgorman@suse.de, dave@sr71.net, hannes@cmpxchg.org, tony.luck@intel.com, matthew.garrett@nebula.com, riel@redhat.com, arjan@linux.intel.com, srinivas.pandruvada@linux.intel.com, willy@linux.intel.com, kamezawa.hiroyu@jp.fujitsu.com, lenb@kernel.org, rjw@sisk.pl Cc: gargankita@gmail.com, paulmck@linux.vnet.ibm.com, svaidy@linux.vnet.ibm.com, andi@firstfloor.org, isimatu.yasuaki@jp.fujitsu.com, santosh.shilimkar@ti.com, kosaki.motohiro@gmail.com, srivatsa.bhat@linux.vnet.ibm.com, linux-pm@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Under CONFIG_DEBUG_PAGEALLOC, we have numerous checks and balances to verify the correctness of various sorted-buddy operations. But some of them are very expensive and hence can't be enabled while benchmarking the code. (They should be used only to verify that the code is working correctly, as a precursor to benchmarking the performance). The check to see if a page given as input to del_from_freelist() indeed belongs to that freelist, is one such very expensive check. Drop it. Signed-off-by: Srivatsa S. Bhat --- mm/page_alloc.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index d5acea7..178f210 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -812,6 +812,7 @@ static void del_from_freelist(struct page *page, struct free_list *free_list, #ifdef CONFIG_DEBUG_PAGEALLOC WARN(region->nr_free < 0, "%s: nr_free is negative\n", __func__); +#if 0 /* Verify whether this page indeed belongs to this free list! */ list_for_each(p, &free_list->list) { @@ -820,6 +821,7 @@ static void del_from_freelist(struct page *page, struct free_list *free_list, } WARN(1, "%s: page doesn't belong to the given freelist!\n", __func__); +#endif page_found: #endif -- 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