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LKML: Nick Piggin: [patch] mm: cleanup bootmem
<?xml version="1.0" encoding="UTF-8" standalone="yes"?> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /><title>LKML: Nick Piggin: [patch] mm: cleanup bootmem</title><link href="/css/message.css" rel="stylesheet" type="text/css" /><link href="/css/wrap.css" rel="alternate stylesheet" type="text/css" title="wrap" /><link href="/css/nowrap.css" rel="stylesheet" type="text/css" title="nowrap" /><link href="/favicon.ico" rel="shortcut icon" /><script src="/js/simple-calendar.js" type="text/javascript"></script><script src="/js/styleswitcher.js" type="text/javascript"></script><link rel="alternate" type="application/rss+xml" title="lkml.org : last 100 messages" href="/rss.php" /><link rel="alternate" type="application/rss+xml" title="lkml.org : last messages by Nick Piggin" href="/groupie.php?aid=29547" /><!--Matomo--><script> var _paq = window._paq = window._paq || []; /* tracker methods like "setCustomDimension" should be called before "trackPageView" */ _paq.push(["setDoNotTrack", true]); _paq.push(["disableCookies"]); _paq.push(['trackPageView']); _paq.push(['enableLinkTracking']); (function() { var u="//m.lkml.org/"; _paq.push(['setTrackerUrl', u+'matomo.php']); _paq.push(['setSiteId', '1']); var d=document, g=d.createElement('script'), s=d.getElementsByTagName('script')[0]; g.async=true; g.src=u+'matomo.js'; s.parentNode.insertBefore(g,s); })(); </script><!--End Matomo Code--></head><body onload="es.jasper.simpleCalendar.init();" itemscope="itemscope" itemtype="http://schema.org/BlogPosting"><table border="0" cellpadding="0" cellspacing="0"><tr><td width="180" align="center"><a href="/"><img style="border:0;width:135px;height:32px" src="/images/toprowlk.gif" alt="lkml.org" /></a></td><td width="32">聽</td><td class="nb"><div><a class="nb" href="/lkml"> [lkml]</a> 聽 <a class="nb" href="/lkml/2006"> [2006]</a> 聽 <a class="nb" href="/lkml/2006/1"> [Jan]</a> 聽 <a class="nb" href="/lkml/2006/1/14"> [14]</a> 聽 <a class="nb" href="/lkml/last100"> [last100]</a> 聽 <a href="/rss.php"><img src="/images/rss-or.gif" border="0" alt="RSS Feed" /></a></div><div>Views: <a href="#" class="nowrap" onclick="setActiveStyleSheet('wrap');return false;">[wrap]</a><a href="#" class="wrap" onclick="setActiveStyleSheet('nowrap');return false;">[no wrap]</a> 聽 <a class="nb" href="/lkml/mheaders/2006/1/14/77" onclick="this.href='/lkml/headers'+'/2006/1/14/77';">[headers]</a>聽 <a href="/lkml/bounce/2006/1/14/77">[forward]</a>聽 </div></td><td width="32">聽</td></tr><tr><td valign="top"><div class="es-jasper-simpleCalendar" baseurl="/lkml/"></div><div class="threadlist">Messages in this thread</div><ul class="threadlist"><li class="root"><a href="/lkml/2006/1/14/77">First message in thread</a></li><li class="origin"><a href="/lkml/2006/1/14/83">Nick Piggin</a><ul><li><a href="/lkml/2006/1/14/83">Nick Piggin</a></li><li><a href="/lkml/2006/1/14/185">Linus Torvalds</a><ul><li><a href="/lkml/2006/1/14/189">Nick Piggin</a><ul><li><a href="/lkml/2006/1/14/190">Nick Piggin</a><ul><li><a href="/lkml/2006/1/14/192">Linus Torvalds</a></li></ul></li></ul></li></ul></li></ul></li></ul><div class="threadlist">Patch in this message</div><ul class="threadlist"><li><a href="/lkml/diff/2006/1/14/77/1">Get diff 1</a></li></ul></td><td width="32" rowspan="2" class="c" valign="top"><img src="/images/icornerl.gif" width="32" height="32" alt="/" /></td><td class="c" rowspan="2" valign="top" style="padding-top: 1em"><table><tr><td><table><tr><td class="lp">Date</td><td class="rp" itemprop="datePublished">Sat, 14 Jan 2006 23:42:00 +1100</td></tr><tr><td class="lp">From</td><td class="rp" itemprop="author">Nick Piggin <></td></tr><tr><td class="lp">Subject</td><td class="rp" itemprop="name">[patch] mm: cleanup bootmem</td></tr></table></td><td></td></tr></table><pre itemprop="articleBody">Objections?<br /><br />-- <br />SUSE Labs, Novell Inc.<br /><br />The bootmem code added to page_alloc.c duplicated some page freeing code<br />that it really doesn't need to because it is not so performance critical.<br /><br />While we're here, make prefetching work properly by actually prefetching<br />the page we're about to use before prefetching ahead to the next one (ie.<br />get the most important transaction started first). Also prefetch just a<br />single page ahead rather than leaving a gap of 16.<br /><br />Signed-off-by: Nick Piggin <npiggin@suse.de><br /><br />Index: linux-2.6/mm/page_alloc.c<br />===================================================================<br />--- linux-2.6.orig/mm/page_alloc.c<br />+++ linux-2.6/mm/page_alloc.c<br />@@ -55,8 +55,6 @@ unsigned long totalhigh_pages __read_mos<br /> long nr_swap_pages;<br /> int percpu_pagelist_fraction;<br /> <br />-static void fastcall free_hot_cold_page(struct page *page, int cold);<br />-<br /> /*<br /> * results with 256, 32 in the lowmem_reserve sysctl:<br /> * 1G machine -> (16M dma, 800M-16M normal, 1G-800M high)<br />@@ -444,28 +442,23 @@ void fastcall __init __free_pages_bootme<br /> if (order == 0) {<br /> __ClearPageReserved(page);<br /> set_page_count(page, 0);<br />-<br />- free_hot_cold_page(page, 0);<br />+ set_page_refs(page, 0);<br />+ __free_page(page);<br /> } else {<br />- LIST_HEAD(list);<br /> int loop;<br /> <br />+ prefetchw(page);<br /> for (loop = 0; loop < BITS_PER_LONG; loop++) {<br /> struct page *p = &page[loop];<br /> <br />- if (loop + 16 < BITS_PER_LONG)<br />- prefetchw(p + 16);<br />+ if (loop + 1 < BITS_PER_LONG)<br />+ prefetchw(p + 1);<br /> __ClearPageReserved(p);<br /> set_page_count(p, 0);<br /> }<br /> <br />- arch_free_page(page, order);<br />-<br />- mod_page_state(pgfree, 1 << order);<br />-<br />- list_add(&page->lru, &list);<br />- kernel_map_pages(page, 1 << order, 0);<br />- free_pages_bulk(page_zone(page), 1, &list, order);<br />+ set_page_refs(page, order);<br />+ __free_pages(page, order);<br /> }<br /> }<br /> </pre></td><td width="32" rowspan="2" class="c" valign="top"><img src="/images/icornerr.gif" width="32" height="32" alt="\" /></td></tr><tr><td align="right" valign="bottom"> 聽 </td></tr><tr><td align="right" valign="bottom">聽</td><td class="c" valign="bottom" style="padding-bottom: 0px"><img src="/images/bcornerl.gif" width="32" height="32" alt="\" /></td><td class="c">聽</td><td class="c" valign="bottom" style="padding-bottom: 0px"><img src="/images/bcornerr.gif" width="32" height="32" alt="/" /></td></tr><tr><td align="right" valign="top" colspan="2"> 聽 </td><td class="lm">Last update: 2006-01-14 13:47 聽聽 [from the cache]<br />漏2003-2020 <a href="http://blog.jasper.es/"><span itemprop="editor">Jasper Spaans</span></a>|hosted at <a href="https://www.digitalocean.com/?refcode=9a8e99d24cf9">Digital Ocean</a> and my Meterkast|<a href="http://blog.jasper.es/categories.html#lkml-ref">Read the blog</a></td><td>聽</td></tr></table><script language="javascript" src="/js/styleswitcher.js" type="text/javascript"></script></body></html>