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<?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: David Howells: [PATCH 2/12]: MUTEX: Provide SWAP-based mutex for FRV</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 David Howells" href="/groupie.php?aid=345" /><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></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/2005"> [2005]</a> 聽 <a class="nb" href="/lkml/2005/12"> [Dec]</a> 聽 <a class="nb" href="/lkml/2005/12/16"> [16]</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/2005/12/16/270" onclick="this.href='/lkml/headers'+'/2005/12/16/270';">[headers]</a>聽 <a href="/lkml/bounce/2005/12/16/270">[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/2005/12/16/277">First message in thread</a></li><li><a href="/lkml/2005/12/16/277">David Howells</a><ul><li class="origin"><a href="">David Howells</a></li><li><a href="/lkml/2005/12/16/271">David Howells</a></li><li><a href="/lkml/2005/12/16/272">David Howells</a></li><li><a href="/lkml/2005/12/16/273">David Howells</a></li><li><a href="/lkml/2005/12/16/274">David Howells</a></li><li><a href="/lkml/2005/12/16/275">David Howells</a></li><li><a href="/lkml/2005/12/16/276">David Howells</a></li><li><a href="/lkml/2005/12/16/278">David Howells</a></li><li><a href="/lkml/2005/12/16/279">David Howells</a></li><li><a href="/lkml/2005/12/16/280">David Howells</a></li><li><a href="/lkml/2005/12/16/281">David Howells</a></li><li><a href="/lkml/2005/12/16/282">David Howells</a></li><li><a href="/lkml/2005/12/16/335">Steven Rostedt</a><ul><li><a href="/lkml/2005/12/17/13">Linus Torvalds</a><ul><li><a href="/lkml/2005/12/17/60">David Howells</a><ul><li><a href="/lkml/2005/12/17/63">Linus Torvalds</a></li></ul></li></ul></li><li><a href="/lkml/2005/12/17/15">Nick Piggin</a><ul><li><a href="/lkml/2005/12/17/24">Steven Rostedt</a></li></ul></li></ul></li></ul></li></ul><div class="threadlist">Patch in this message</div><ul class="threadlist"><li><a href="/lkml/diff/2005/12/16/270/1">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">Fri, 16 Dec 2005 23:13:07 GMT</td></tr><tr><td class="lp">From</td><td class="rp" itemprop="author">David Howells <></td></tr><tr><td class="lp">Subject</td><td class="rp" itemprop="name">[PATCH 2/12]: MUTEX: Provide SWAP-based mutex for FRV</td></tr></table></td><td></td></tr></table><pre itemprop="articleBody">The attached patch permits the FRV architecture to make use of the xchg()<br />based mutex, overriding the use of xchg() with something based on the FRV<br />SWAP/SWAPI atomic op instructions. Note that xchg() in FRV is not actually<br />based on SWAP/SWAPI at the moment.<br /><br />The patch also renames DECLARE_MUTEX*() for this arch to DECLARE_SEM_MUTEX*().<br /><br />Signed-Off-By: David Howells <dhowells@redhat.com><br />---<br />warthog>diffstat -p1 mutex-frv-2615rc5-2.diff<br /> arch/frv/Kconfig | 4 ++++<br /> arch/frv/kernel/irq.c | 2 +-<br /> include/asm-frv/system.h | 19 +++++++++++++++++++<br /> 3 files changed, 24 insertions(+), 1 deletion(-)<br /><br />diff -uNrp linux-2.6.15-rc5/arch/frv/Kconfig linux-2.6.15-rc5-mutex/arch/frv/Kconfig<br />--- linux-2.6.15-rc5/arch/frv/Kconfig 2005-08-30 13:56:10.000000000 +0100<br />+++ linux-2.6.15-rc5-mutex/arch/frv/Kconfig 2005-12-16 17:40:50.000000000 +0000<br />@@ -10,6 +10,10 @@ config UID16<br /> bool<br /> default y<br /> <br />+config ARCH_XCHG_MUTEX<br />+ bool<br />+ default y<br />+<br /> config RWSEM_GENERIC_SPINLOCK<br /> bool<br /> default y<br />diff -uNrp linux-2.6.15-rc5/include/asm-frv/system.h linux-2.6.15-rc5-mutex/include/asm-frv/system.h<br />--- linux-2.6.15-rc5/include/asm-frv/system.h 2005-06-22 13:52:26.000000000 +0100<br />+++ linux-2.6.15-rc5-mutex/include/asm-frv/system.h 2005-12-16 21:43:32.000000000 +0000<br />@@ -99,6 +99,25 @@ do { \<br /> ((__get_PSR() & PSR_PIL) >= PSR_PIL_14)<br /> <br /> /*<br />+ * mutex implementation<br />+ */<br />+#define __mutex_trylock(mutex) \<br />+({ \<br />+ int oldstate; \<br />+ \<br />+ asm volatile("swap%I0 %M0,%1" \<br />+ : "+m"(mutex->state), "=r"(oldstate) \<br />+ : "1"(1) \<br />+ : "memory"); \<br />+ \<br />+ oldstate == 0; \<br />+})<br />+<br />+#define __mutex_release(mutex) do { (mutex)->state = 0; } while(0)<br />+<br />+#define mutex_is_locked(mutex) ((mutex)->state)<br />+<br />+/*<br /> * Force strict CPU ordering.<br /> */<br /> #define nop() asm volatile ("nop"::)<br />diff -uNrp linux-2.6.15-rc5/arch/frv/kernel/irq.c linux-2.6.15-rc5-mutex/arch/frv/kernel/irq.c<br />--- linux-2.6.15-rc5/arch/frv/kernel/irq.c 2005-03-02 12:07:44.000000000 +0000<br />+++ linux-2.6.15-rc5-mutex/arch/frv/kernel/irq.c 2005-12-15 17:14:56.000000000 +0000<br />@@ -503,7 +503,7 @@ void free_irq(unsigned int irq, void *de<br /> * unassigned IRQ will cause GxICR_DETECT to be set<br /> */<br /> <br />-static DECLARE_MUTEX(probe_sem);<br />+static DECLARE_SEM_MUTEX(probe_sem);<br /> <br /> /**<br /> * probe_irq_on - begin an interrupt autodetect<br />-<br />To unsubscribe from this list: send the line "unsubscribe linux-kernel" in<br />the body of a message to majordomo@vger.kernel.org<br />More majordomo info at <a href="http://vger.kernel.org/majordomo-info.html">http://vger.kernel.org/majordomo-info.html</a><br />Please read the FAQ at <a href="http://www.tux.org/lkml/">http://www.tux.org/lkml/</a><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: 2005-12-17 00:16 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>