From: Peter Zijlstra <a.p.zijlstra@chello.nl>
To: Linus Torvalds <torvalds@linux-foundation.org>,
Ingo Molnar <mingo@elte.hu>, Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org, akpm@linux-foundation.org,
efault@gmx.de, Arne Jansen <lists@die-jansens.de>,
Peter Zijlstra <a.p.zijlstra@chello.nl>
Subject: [PATCH 2/3] printk, lockdep: Remove lockdep_off() usage
Date: Thu, 09 Jun 2011 15:06:49 +0200 [thread overview]
Message-ID: <20110609131307.539373927@chello.nl> (raw)
In-Reply-To: 20110609130647.937204592@chello.nl
[-- Attachment #1: printk-remove-lockdep_off.patch --]
[-- Type: text/plain, Size: 1661 bytes --]
Remove the lockdep_off() usage from printk(). Also add a
debug_locks_off() call to zap_locks() since that'll mess up the lock
state in a royal way anyway. Further switch to local_irq_ ops so that
the irq state is properly tracked (raw_local_irq_* isn't tracked by
lockdep, causing confusion). Also drop superfluous preempt_disable(),
disabling IRQs already avoids scheduling.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
---
kernel/printk.c | 9 +++------
1 file changed, 3 insertions(+), 6 deletions(-)
Index: linux-2.6/kernel/printk.c
===================================================================
--- linux-2.6.orig/kernel/printk.c
+++ linux-2.6/kernel/printk.c
@@ -686,6 +686,7 @@ static void zap_locks(void)
oops_timestamp = jiffies;
+ debug_locks_off();
/* If a crash is occurring, make sure we can't deadlock */
spin_lock_init(&logbuf_lock);
/* And make sure that we print immediately */
@@ -838,9 +839,8 @@ asmlinkage int vprintk(const char *fmt,
boot_delay_msec();
printk_delay();
- preempt_disable();
/* This stops the holder of console_sem just where we want him */
- raw_local_irq_save(flags);
+ local_irq_save(flags);
this_cpu = smp_processor_id();
/*
@@ -861,7 +861,6 @@ asmlinkage int vprintk(const char *fmt,
zap_locks();
}
- lockdep_off();
spin_lock(&logbuf_lock);
printk_cpu = this_cpu;
@@ -958,11 +957,9 @@ asmlinkage int vprintk(const char *fmt,
if (console_trylock_for_printk(this_cpu))
console_unlock();
- lockdep_on();
out_restore_irqs:
- raw_local_irq_restore(flags);
+ local_irq_restore(flags);
- preempt_enable();
return printed_len;
}
EXPORT_SYMBOL(printk);
next prev parent reply other threads:[~2011-06-09 13:14 UTC|newest]
Thread overview: 31+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-06-09 13:06 [PATCH 0/3] printk: Remove lockdep_off() and wakeups Peter Zijlstra
2011-06-09 13:06 ` [PATCH 1/3] printk: Release console_sem after logbuf_lock Peter Zijlstra
2011-06-09 20:06 ` Andrew Morton
2011-06-09 20:27 ` Ingo Molnar
2011-06-09 20:54 ` Peter Zijlstra
2011-06-09 21:07 ` Andrew Morton
2011-06-09 23:57 ` Hugh Dickins
2011-06-10 0:08 ` Andrew Morton
2011-06-10 9:33 ` Ingo Molnar
2011-06-10 9:40 ` Peter Zijlstra
2011-06-10 9:42 ` Peter Zijlstra
2011-06-10 11:28 ` Peter Zijlstra
2011-06-10 12:30 ` Peter Zijlstra
2011-06-10 12:34 ` Ingo Molnar
2011-06-10 12:41 ` Peter Zijlstra
2011-06-10 12:42 ` Peter Zijlstra
2011-06-23 19:03 ` Pavel Machek
2011-06-10 9:30 ` Ingo Molnar
2011-06-10 10:15 ` Peter Zijlstra
2011-06-09 13:06 ` Peter Zijlstra [this message]
2011-06-10 13:23 ` [PATCH 2/3] printk, lockdep: Remove lockdep_off() usage Peter Zijlstra
2011-06-09 13:06 ` [PATCH 3/3] printk: Avoid all wakeups from printk Peter Zijlstra
2011-06-09 13:32 ` Ingo Molnar
2011-06-09 13:40 ` Peter Zijlstra
2011-06-09 13:55 ` Ingo Molnar
2011-06-09 14:06 ` Peter Zijlstra
2011-06-09 14:19 ` Ingo Molnar
2011-06-09 14:23 ` Peter Zijlstra
2011-06-09 15:47 ` Linus Torvalds
2011-06-09 15:51 ` Ingo Molnar
2011-06-09 16:25 ` Peter Zijlstra
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