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LKML: Ingo Molnar: Re: [PATCH 1/19] MUTEX: Introduce simple mutex implementation
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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/2005/12/13"> [13]</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/2005/12/13/108" onclick="this.href='/lkml/headers'+'/2005/12/13/108';">[headers]</a>聽 <a href="/lkml/bounce/2005/12/13/108">[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/2005/12/12/244">First message in thread</a></li><li><a href="/lkml/2005/12/12/268">Andrew Morton</a><ul><li><a href="/lkml/2005/12/13/30">Ingo Molnar</a><ul><li><a href="/lkml/2005/12/13/32">Andi Kleen</a><ul><li><a href="/lkml/2005/12/13/74">Andrew Morton</a><ul><li><a href="/lkml/2005/12/13/76">Andi Kleen</a></li><li><a href="/lkml/2005/12/13/81">Christoph Hellwig</a></li></ul></li></ul></li><li><a href="/lkml/2005/12/13/33">Arjan van de Ven</a><ul><li><a href="/lkml/2005/12/13/83">Ingo Molnar</a><ul><li><a href="/lkml/2005/12/13/87">Andi Kleen</a></li><li><a href="/lkml/2005/12/13/95">Arjan van de Ven</a></li></ul></li></ul></li><li><a href="/lkml/2005/12/13/78">Christoph Hellwig</a><ul><li><a href="/lkml/2005/12/13/102">Ingo Molnar</a><ul><li><a href="/lkml/2005/12/13/109">Ingo Molnar</a></li></ul></li></ul></li><li class="origin"><a href="">Ingo Molnar</a></li></ul></li><li><a href="/lkml/2005/12/13/127">David Howells</a><ul><li><a href="/lkml/2005/12/13/139">Matthew Wilcox</a></li></ul></li></ul></li></ul><div class="threadlist">Patches in this message</div><ul class="threadlist"><li><a href="/lkml/diff/2005/12/13/108/1">Get diff 1</a></li><li><a href="/lkml/diff/2005/12/13/108/2">Get diff 2</a></li><li><a href="/lkml/diff/2005/12/13/108/3">Get diff 3</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">Tue, 13 Dec 2005 10:55:44 +0100</td></tr><tr><td class="lp">From</td><td class="rp" itemprop="author">Ingo Molnar <></td></tr><tr><td class="lp">Subject</td><td class="rp" itemprop="name">Re: [PATCH 1/19] MUTEX: Introduce simple mutex implementation</td></tr></table></td><td></td></tr></table><pre itemprop="articleBody"><br />* Ingo Molnar <mingo@elte.hu> wrote:<br /><br />> all this simplified the 'compatibility conversion' to the patch below. <br />> No other non-generic changes are needed.<br /><br />there were 3 more patches needed, which convert some semaphores to <br />completions:<br /><br /> sx8-sem2completions.patch<br /> cpu5wdt-sem2completions.patch<br /> ide-gendev-sem-to-completion.patch<br /><br />all attached.<br /><br /> Ingo<br /> drivers/block/sx8.c | 11 ++++++-----<br /> 1 files changed, 6 insertions(+), 5 deletions(-)<br /><br />Index: linux/drivers/block/sx8.c<br />===================================================================<br />--- linux.orig/drivers/block/sx8.c<br />+++ linux/drivers/block/sx8.c<br />@@ -27,6 +27,7 @@<br /> #include <linux/time.h><br /> #include <linux/hdreg.h><br /> #include <linux/dma-mapping.h><br />+#include <linux/completion.h><br /> #include <asm/io.h><br /> #include <asm/semaphore.h><br /> #include <asm/uaccess.h><br />@@ -303,7 +304,7 @@ struct carm_host {<br /> <br /> struct work_struct fsm_task;<br /> <br />- struct semaphore probe_sem;<br />+ struct completion probe_comp;<br /> };<br /> <br /> struct carm_response {<br />@@ -1365,7 +1366,7 @@ static void carm_fsm_task (void *_data)<br /> }<br /> <br /> case HST_PROBE_FINISHED:<br />- up(&host->probe_sem);<br />+ complete(&host->probe_comp);<br /> break;<br /> <br /> case HST_ERROR:<br />@@ -1641,7 +1642,7 @@ static int carm_init_one (struct pci_dev<br /> host->flags = pci_dac ? FL_DAC : 0;<br /> spin_lock_init(&host->lock);<br /> INIT_WORK(&host->fsm_task, carm_fsm_task, host);<br />- init_MUTEX_LOCKED(&host->probe_sem);<br />+ init_completion(&host->probe_comp);<br /> <br /> for (i = 0; i < ARRAY_SIZE(host->req); i++)<br /> host->req[i].tag = i;<br />@@ -1710,8 +1711,8 @@ static int carm_init_one (struct pci_dev<br /> if (rc)<br /> goto err_out_free_irq;<br /> <br />- DPRINTK("waiting for probe_sem\n");<br />- down(&host->probe_sem);<br />+ DPRINTK("waiting for probe_comp\n");<br />+ wait_for_completion(&host->probe_comp);<br /> <br /> printk(KERN_INFO "%s: pci %s, ports %d, io %lx, irq %u, major %d\n",<br /> host->name, pci_name(pdev), (int) CARM_MAX_PORTS, drivers/char/watchdog/cpu5wdt.c | 9 +++++----<br /> 1 files changed, 5 insertions(+), 4 deletions(-)<br /><br />Index: linux/drivers/char/watchdog/cpu5wdt.c<br />===================================================================<br />--- linux.orig/drivers/char/watchdog/cpu5wdt.c<br />+++ linux/drivers/char/watchdog/cpu5wdt.c<br />@@ -28,6 +28,7 @@<br /> #include <linux/init.h><br /> #include <linux/ioport.h><br /> #include <linux/timer.h><br />+#include <linux/completion.h><br /> #include <linux/jiffies.h><br /> #include <asm/io.h><br /> #include <asm/uaccess.h><br />@@ -57,7 +58,7 @@ static int ticks = 10000;<br /> /* some device data */<br /> <br /> static struct {<br />- struct semaphore stop;<br />+ struct completion stop;<br /> volatile int running;<br /> struct timer_list timer;<br /> volatile int queue;<br />@@ -85,7 +86,7 @@ static void cpu5wdt_trigger(unsigned lon<br /> }<br /> else {<br /> /* ticks doesn't matter anyway */<br />- up(&cpu5wdt_device.stop);<br />+ complete(&cpu5wdt_device.stop);<br /> }<br /> <br /> }<br />@@ -239,7 +240,7 @@ static int __devinit cpu5wdt_init(void)<br /> if ( !val )<br /> printk(KERN_INFO PFX "sorry, was my fault\n");<br /> <br />- init_MUTEX_LOCKED(&cpu5wdt_device.stop);<br />+ init_completion(&cpu5wdt_device.stop);<br /> cpu5wdt_device.queue = 0;<br /> <br /> clear_bit(0, &cpu5wdt_device.inuse);<br />@@ -269,7 +270,7 @@ static void __devexit cpu5wdt_exit(void)<br /> {<br /> if ( cpu5wdt_device.queue ) {<br /> cpu5wdt_device.queue = 0;<br />- down(&cpu5wdt_device.stop);<br />+ wait_for_completion(&cpu5wdt_device.stop);<br /> }<br /> <br /> misc_deregister(&cpu5wdt_misc);The following patch is from Montavista. I modified it slightly.<br />Semaphores are currently being used where it makes more sense for<br />completions. This patch corrects that.<br /><br />-- Steve<br /><br />Signed-off-by: Steven Rostedt <rostedt@goodmis.org><br /><br />Source: MontaVista Software, Inc.<br />Signed-off-by: Aleksey Makarov <amakarov@ru.mvista.com><br />Description:<br /> The patch changes semaphores that are initialized as <br /> locked to complete().<br /><br /> drivers/ide/ide-probe.c | 4 ++--<br /> drivers/ide/ide.c | 8 ++++----<br /> include/linux/ide.h | 5 +++--<br /> 3 files changed, 9 insertions(+), 8 deletions(-)<br /><br />Index: linux/drivers/ide/ide-probe.c<br />===================================================================<br />--- linux.orig/drivers/ide/ide-probe.c<br />+++ linux/drivers/ide/ide-probe.c<br />@@ -655,7 +655,7 @@ static void hwif_release_dev (struct dev<br /> {<br /> ide_hwif_t *hwif = container_of(dev, ide_hwif_t, gendev);<br /> <br />- up(&hwif->gendev_rel_sem);<br />+ complete(&hwif->gendev_rel_comp);<br /> }<br /> <br /> static void hwif_register (ide_hwif_t *hwif)<br />@@ -1325,7 +1325,7 @@ static void drive_release_dev (struct de<br /> drive->queue = NULL;<br /> spin_unlock_irq(&ide_lock);<br /> <br />- up(&drive->gendev_rel_sem);<br />+ complete(&drive->gendev_rel_comp);<br /> }<br /> <br /> /*<br />Index: linux/drivers/ide/ide.c<br />===================================================================<br />--- linux.orig/drivers/ide/ide.c<br />+++ linux/drivers/ide/ide.c<br />@@ -222,7 +222,7 @@ static void init_hwif_data(ide_hwif_t *h<br /> hwif->mwdma_mask = 0x80; /* disable all mwdma */<br /> hwif->swdma_mask = 0x80; /* disable all swdma */<br /> <br />- sema_init(&hwif->gendev_rel_sem, 0);<br />+ init_completion(&hwif->gendev_rel_comp);<br /> <br /> default_hwif_iops(hwif);<br /> default_hwif_transport(hwif);<br />@@ -245,7 +245,7 @@ static void init_hwif_data(ide_hwif_t *h<br /> drive->is_flash = 0;<br /> drive->vdma = 0;<br /> INIT_LIST_HEAD(&drive->list);<br />- sema_init(&drive->gendev_rel_sem, 0);<br />+ init_completion(&drive->gendev_rel_comp);<br /> }<br /> }<br /> <br />@@ -602,7 +602,7 @@ void ide_unregister(unsigned int index)<br /> }<br /> spin_unlock_irq(&ide_lock);<br /> device_unregister(&drive->gendev);<br />- down(&drive->gendev_rel_sem);<br />+ wait_for_completion(&drive->gendev_rel_comp);<br /> spin_lock_irq(&ide_lock);<br /> }<br /> hwif->present = 0;<br />@@ -662,7 +662,7 @@ void ide_unregister(unsigned int index)<br /> /* More messed up locking ... */<br /> spin_unlock_irq(&ide_lock);<br /> device_unregister(&hwif->gendev);<br />- down(&hwif->gendev_rel_sem);<br />+ wait_for_completion(&hwif->gendev_rel_comp);<br /> <br /> /*<br /> * Remove us from the kernel's knowledge<br />Index: linux/include/linux/ide.h<br />===================================================================<br />--- linux.orig/include/linux/ide.h<br />+++ linux/include/linux/ide.h<br />@@ -18,6 +18,7 @@<br /> #include <linux/bio.h><br /> #include <linux/device.h><br /> #include <linux/pci.h><br />+#include <linux/completion.h><br /> #include <asm/byteorder.h><br /> #include <asm/system.h><br /> #include <asm/io.h><br />@@ -759,7 +760,7 @@ typedef struct ide_drive_s {<br /> int crc_count; /* crc counter to reduce drive speed */<br /> struct list_head list;<br /> struct device gendev;<br />- struct semaphore gendev_rel_sem; /* to deal with device release() */<br />+ struct completion gendev_rel_comp; /* to deal with device release() */<br /> } ide_drive_t;<br /> <br /> #define to_ide_device(dev)container_of(dev, ide_drive_t, gendev)<br />@@ -915,7 +916,7 @@ typedef struct hwif_s {<br /> unsigned sg_mapped : 1; /* sg_table and sg_nents are ready */<br /> <br /> struct device gendev;<br />- struct semaphore gendev_rel_sem; /* To deal with device release() */<br />+ struct completion gendev_rel_comp; /* To deal with device release() */<br /> <br /> void *hwif_data; /* extra hwif data */<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: 2005-12-13 10:58 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>