From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Mon, 7 Nov 2005 17:53:58 -0800 From: Andrew Morton Subject: Re: [PATCH]: Cleanup of __alloc_pages Message-Id: <20051107175358.62c484a3.akpm@osdl.org> In-Reply-To: <20051107174349.A8018@unix-os.sc.intel.com> References: <20051107174349.A8018@unix-os.sc.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: "Rohit, Seth" Cc: torvalds@osdl.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org List-ID: "Rohit, Seth" wrote: > > [PATCH]: Clean up of __alloc_pages. Couple of difference from original behavior: > 1- remove the initial reclaim logic > 2- GFP_HIGH pages are allowed to go little below watermark sooner. > 3- Search for free pages unconditionally after direct reclaim. Would it be possible to break these into three separate patches? The cleanup part should be #1. > +/* get_page_from_freeliest loops through all the possible zones > + * to find out if it can allocate a page. can_try_harder can have following > + * values: > + * -1 => No need to check for the watermarks. > + * 0 => Don't go too low down in deeps below the low watermark (GFP_HIGH) > + * 1 => Go far below the low watermark. See zone_watermark_ok (RT TASK) > + * > + * cpuset check is not performed when the skip_cpuset_chk flag is set. > + */ > + > +static struct page * > +get_page_from_freelist(gfp_t gfp_mask, unsigned int order, struct zone **zones, > + int can_try_harder, int skip_cpuset_chk) > +{ > + struct zone *z; > + struct page *page = NULL; > + int classzone_idx = zone_idx(zones[0]); > + int i; > + > + /* > + * Go through the zonelist once, looking for a zone with enough free. > + * See also cpuset_zone_allowed() comment in kernel/cpuset.c. > + */ > + for (i = 0; (z = zones[i]) != NULL; i++) { > + if (!skip_cpuset_chk && (!cpuset_zone_allowed(z, gfp_mask))) It'd be nice to not have the `skip_cpuset_chk' flag there. a) it gives Linus conniptions and b) it's a little extra overhead for !CONFIG_CPUSETS kernels. > - zone_statistics(zonelist, z); > + zone_statistics(zonelist, page_zone(page)); Evaluating page_zone() is not completely trivial. Can we avoid the above? -- 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