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LKML: Ingo Molnar: [patch 11/21] mutex subsystem, more debugging code
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[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/2006/1/4"> [4]</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/2006/1/4/152" onclick="this.href='/lkml/headers'+'/2006/1/4/152';">[headers]</a>聽 <a href="/lkml/bounce/2006/1/4/152">[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/2006/1/4/152">First message in thread</a></li><li class="origin"><a href="">Ingo Molnar</a></li></ul><div class="threadlist">Patch in this message</div><ul class="threadlist"><li><a href="/lkml/diff/2006/1/4/152/1">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">Wed, 4 Jan 2006 15:43:19 +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">[patch 11/21] mutex subsystem, more debugging code</td></tr></table></td><td></td></tr></table><pre itemprop="articleBody"><br />more mutex debugging: check for held locks during memory freeing,<br />task exit, enable sysrq printouts, etc.<br /><br />Signed-off-by: Ingo Molnar <mingo@elte.hu><br />Signed-off-by: Arjan van de Ven <arjan@infradead.org><br /><br />----<br /><br /> arch/i386/mm/pageattr.c | 4 ++++<br /> drivers/char/sysrq.c | 19 +++++++++++++++++++<br /> include/linux/mm.h | 4 ++++<br /> kernel/exit.c | 5 +++++<br /> kernel/sched.c | 1 +<br /> mm/page_alloc.c | 3 +++<br /> mm/slab.c | 1 +<br /> 7 files changed, 37 insertions(+)<br /><br />Index: linux/arch/i386/mm/pageattr.c<br />===================================================================<br />--- linux.orig/arch/i386/mm/pageattr.c<br />+++ linux/arch/i386/mm/pageattr.c<br />@@ -207,6 +207,10 @@ void kernel_map_pages(struct page *page,<br /> {<br /> if (PageHighMem(page))<br /> return;<br />+ if (!enable)<br />+ mutex_debug_check_no_locks_freed(page_address(page),<br />+ page_address(page+numpages));<br />+<br /> /* the return value is ignored - the calls cannot fail,<br /> * large pages are disabled at boot time.<br /> */<br />Index: linux/drivers/char/sysrq.c<br />===================================================================<br />--- linux.orig/drivers/char/sysrq.c<br />+++ linux/drivers/char/sysrq.c<br />@@ -153,6 +153,21 @@ static struct sysrq_key_op sysrq_mountro<br /> <br /> /* END SYNC SYSRQ HANDLERS BLOCK */<br /> <br />+#ifdef CONFIG_DEBUG_MUTEXES<br />+<br />+static void<br />+sysrq_handle_showlocks(int key, struct pt_regs *pt_regs, struct tty_struct *tty)<br />+{<br />+ mutex_debug_show_all_locks();<br />+}<br />+<br />+static struct sysrq_key_op sysrq_showlocks_op = {<br />+ .handler = sysrq_handle_showlocks,<br />+ .help_msg = "show-all-locks(D)",<br />+ .action_msg = "Show Locks Held",<br />+};<br />+<br />+#endif<br /> <br /> /* SHOW SYSRQ HANDLERS BLOCK */<br /> <br />@@ -294,7 +309,11 @@ static struct sysrq_key_op *sysrq_key_ta<br /> #else<br /> /* c */ NULL,<br /> #endif<br />+#ifdef CONFIG_DEBUG_MUTEXES<br />+/* d */ &sysrq_showlocks_op,<br />+#else<br /> /* d */ NULL,<br />+#endif<br /> /* e */ &sysrq_term_op,<br /> /* f */ &sysrq_moom_op,<br /> /* g */ NULL,<br />Index: linux/include/linux/mm.h<br />===================================================================<br />--- linux.orig/include/linux/mm.h<br />+++ linux/include/linux/mm.h<br />@@ -13,6 +13,7 @@<br /> #include <linux/rbtree.h><br /> #include <linux/prio_tree.h><br /> #include <linux/fs.h><br />+#include <linux/mutex.h><br /> <br /> struct mempolicy;<br /> struct anon_vma;<br />@@ -978,6 +979,9 @@ static inline void vm_stat_account(struc<br /> static inline void<br /> kernel_map_pages(struct page *page, int numpages, int enable)<br /> {<br />+ if (!PageHighMem(page) && !enable)<br />+ mutex_debug_check_no_locks_freed(page_address(page),<br />+ page_address(page + numpages));<br /> }<br /> #endif<br /> <br />Index: linux/kernel/exit.c<br />===================================================================<br />--- linux.orig/kernel/exit.c<br />+++ linux/kernel/exit.c<br />@@ -29,6 +29,7 @@<br /> #include <linux/syscalls.h><br /> #include <linux/signal.h><br /> #include <linux/cn_proc.h><br />+#include <linux/mutex.h><br /> <br /> #include <asm/uaccess.h><br /> #include <asm/unistd.h><br />@@ -870,6 +871,10 @@ fastcall NORET_TYPE void do_exit(long co<br /> mpol_free(tsk->mempolicy);<br /> tsk->mempolicy = NULL;<br /> #endif<br />+ /*<br />+ * If DEBUG_MUTEXES is on, make sure we are holding no locks:<br />+ */<br />+ mutex_debug_check_no_locks_held(tsk);<br /> <br /> /* PF_DEAD causes final put_task_struct after we schedule. */<br /> preempt_disable();<br />Index: linux/kernel/sched.c<br />===================================================================<br />--- linux.orig/kernel/sched.c<br />+++ linux/kernel/sched.c<br />@@ -4379,6 +4379,7 @@ void show_state(void)<br /> } while_each_thread(g, p);<br /> <br /> read_unlock(&tasklist_lock);<br />+ mutex_debug_show_all_locks();<br /> }<br /> <br /> /**<br />Index: linux/mm/page_alloc.c<br />===================================================================<br />--- linux.orig/mm/page_alloc.c<br />+++ linux/mm/page_alloc.c<br />@@ -400,6 +400,9 @@ void __free_pages_ok(struct page *page, <br /> int reserved = 0;<br /> <br /> arch_free_page(page, order);<br />+ if (!PageHighMem(page))<br />+ mutex_debug_check_no_locks_freed(page_address(page),<br />+ page_address(page+(1<<order)));<br /> <br /> #ifndef CONFIG_MMU<br /> if (order > 0)<br />Index: linux/mm/slab.c<br />===================================================================<br />--- linux.orig/mm/slab.c<br />+++ linux/mm/slab.c<br />@@ -3038,6 +3038,7 @@ void kfree(const void *objp)<br /> local_irq_save(flags);<br /> kfree_debugcheck(objp);<br /> c = page_get_cache(virt_to_page(objp));<br />+ mutex_debug_check_no_locks_freed(objp, objp+obj_reallen(c));<br /> __cache_free(c, (void*)objp);<br /> local_irq_restore(flags);<br /> }<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 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