[PATCH 4/4] sched: Generalize sleep inside spinlock detection

Frederic Weisbecker
2011-06-08T17:48:56Z

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The sleeping inside spinlock detection is actually used
for more general sleeping inside atomic sections
debugging: preemption disabled, rcu read side critical
sections, interrupts, interrupt disabled, etc...

Change the name of the config and its help section to
reflect its more general role.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
---
Documentation/DocBook/kernel-hacking.tmpl | 2 +-
Documentation/SubmitChecklist | 2 +-
Documentation/development-process/4.Coding | 2 +-
Documentation/ja_JP/SubmitChecklist | 2 +-
Documentation/zh_CN/SubmitChecklist | 2 +-
include/linux/kernel.h | 2 +-
kernel/sched.c | 2 +-
lib/Kconfig.debug | 8 +++++---
8 files changed, 12 insertions(+), 10 deletions(-)

diff --git a/Documentation/DocBook/kernel-hacking.tmpl b/Documentation/DocBook/kernel-hacking.tmpl
index 7b3f493..07a9c48 100644
--- a/Documentation/DocBook/kernel-hacking.tmpl
+++ b/Documentation/DocBook/kernel-hacking.tmpl
@@ -409,7 +409,7 @@ cond_resched(); /* Will sleep */


You should always compile your kernel
- <symbol>CONFIG_DEBUG_SPINLOCK_SLEEP</symbol> on, and it will warn
+ <symbol>CONFIG_DEBUG_ATOMIC_SLEEP</symbol> on, and it will warn
you if you break these rules. If you do break
the rules, you will eventually lock up your box.

diff --git a/Documentation/SubmitChecklist b/Documentation/SubmitChecklist
index da0382d..7b13be4 100644
--- a/Documentation/SubmitChecklist
+++ b/Documentation/SubmitChecklist
@@ -53,7 +53,7 @@ kernel patches.

12: Has been tested with CONFIG_PREEMPT, CONFIG_DEBUG_PREEMPT,
CONFIG_DEBUG_SLAB, CONFIG_DEBUG_PAGEALLOC, CONFIG_DEBUG_MUTEXES,
- CONFIG_DEBUG_SPINLOCK, CONFIG_DEBUG_SPINLOCK_SLEEP all simultaneously
+ CONFIG_DEBUG_SPINLOCK, CONFIG_DEBUG_ATOMIC_SLEEP all simultaneously
enabled.

13: Has been build- and runtime tested with and without CONFIG_SMP and
diff --git a/Documentation/development-process/4.Coding b/Documentation/development-process/4.Coding
index f3f1a46..83f5f5b 100644
--- a/Documentation/development-process/4.Coding
+++ b/Documentation/development-process/4.Coding
@@ -244,7 +244,7 @@ testing purposes. In particular, you should turn on:
- DEBUG_SLAB can find a variety of memory allocation and use errors; it
should be used on most development kernels.

- - DEBUG_SPINLOCK, DEBUG_SPINLOCK_SLEEP, and DEBUG_MUTEXES will find a
+ - DEBUG_SPINLOCK, DEBUG_ATOMIC_SLEEP, and DEBUG_MUTEXES will find a
number of common locking errors.

There are quite a few other debugging options, some of which will be
diff --git a/Documentation/ja_JP/SubmitChecklist b/Documentation/ja_JP/SubmitChecklist
index 2df4576..cb5507b 100644
--- a/Documentation/ja_JP/SubmitChecklist
+++ b/Documentation/ja_JP/SubmitChecklist
@@ -68,7 +68,7 @@ Linux ã‚«ãƒ¼ãƒãƒ«ãƒ‘ãƒƒãƒæŠ•ç¨¿è€…å‘ã‘ãƒã‚§ãƒƒã‚¯ãƒªã‚¹ãƒˆ

12: CONFIG_PREEMPT, CONFIG_DEBUG_PREEMPT, CONFIG_DEBUG_SLAB,
CONFIG_DEBUG_PAGEALLOC, CONFIG_DEBUG_MUTEXES, CONFIG_DEBUG_SPINLOCK,
- CONFIG_DEBUG_SPINLOCK_SLEEP ã“ã‚Œã‚‰å…¨ã¦ã‚’åŒæ™‚ã«æœ‰åŠ¹ã«ã—ã¦å‹•ä½œç¢ºèªã‚’
+ CONFIG_DEBUG_ATOMIC_SLEEP ã“ã‚Œã‚‰å…¨ã¦ã‚’åŒæ™‚ã«æœ‰åŠ¹ã«ã—ã¦å‹•ä½œç¢ºèªã‚’
è¡Œã£ã¦ãã ã•ã„ã€‚

13: CONFIG_SMP, CONFIG_PREEMPT ã‚’æœ‰åŠ¹ã«ã—ãŸå ´åˆã¨ç„¡åŠ¹ã«ã—ãŸå ´åˆã®ä¸¡æ–¹ã§
diff --git a/Documentation/zh_CN/SubmitChecklist b/Documentation/zh_CN/SubmitChecklist
index 951415b..4c741d6 100644
--- a/Documentation/zh_CN/SubmitChecklist
+++ b/Documentation/zh_CN/SubmitChecklist
@@ -67,7 +67,7 @@ Linux

12£ºÒÑ¾­Í¨¹ýCONFIG_PREEMPT, CONFIG_DEBUG_PREEMPT,
CONFIG_DEBUG_SLAB, CONFIG_DEBUG_PAGEALLOC, CONFIG_DEBUG_MUTEXES,
- CONFIG_DEBUG_SPINLOCK, CONFIG_DEBUG_SPINLOCK_SLEEP²âÊÔ£¬²¢ÇÒÍ¬Ê±¶¼
+ CONFIG_DEBUG_SPINLOCK, CONFIG_DEBUG_ATOMIC_SLEEP²âÊÔ£¬²¢ÇÒÍ¬Ê±¶¼
Ê¹ÄÜ¡£

13£ºÒÑ¾­¶¼¹¹½¨²¢ÇÒÊ¹ÓÃ»òÕß²»Ê¹ÓÃ CONFIG_SMP ºÍ CONFIG_PREEMPT²âÊÔÖ´ÐÐÊ±¼ä¡£
diff --git a/include/linux/kernel.h b/include/linux/kernel.h
index fb0e732..24b489f 100644
--- a/include/linux/kernel.h
+++ b/include/linux/kernel.h
@@ -121,7 +121,7 @@ extern int _cond_resched(void);
# define might_resched() do { } while (0)
#endif

-#ifdef CONFIG_DEBUG_SPINLOCK_SLEEP
+#ifdef CONFIG_DEBUG_ATOMIC_SLEEP
void __might_sleep(const char *file, int line, int preempt_offset);
/**
* might_sleep - annotation for functions that can sleep
diff --git a/kernel/sched.c b/kernel/sched.c
index 90ad7cf..a5f318b 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -8018,7 +8018,7 @@ void __init sched_init(void)
scheduler_running = 1;
}

-#ifdef CONFIG_DEBUG_SPINLOCK_SLEEP
+#ifdef CONFIG_DEBUG_ATOMIC_SLEEP
static inline int preempt_count_equals(int preempt_offset)
{
int nested = (preempt_count() & ~PREEMPT_ACTIVE) + rcu_preempt_depth();
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index a7dd7b5..81a4f33 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -648,13 +648,15 @@ config TRACE_IRQFLAGS
Enables hooks to interrupt enabling and disabling for
either tracing or lock debugging.

-config DEBUG_SPINLOCK_SLEEP
- bool "Spinlock debugging: sleep-inside-spinlock checking"
+config DEBUG_ATOMIC_SLEEP
+ bool "Sleep inside atomic section checking"
select PREEMPT_COUNT
depends on DEBUG_KERNEL
help
If you say Y here, various routines which may sleep will become very
- noisy if they are called with a spinlock held.
+ noisy if they are called inside atomic sections: when a spinlock is
+ held, inside an rcu read side critical section, inside preempt disabled
+ sections, inside an interrupt, etc...

config DEBUG_LOCKING_API_SELFTESTS
bool "Locking API boot-time self-tests"
--
1.7.5.4