Commit-ID: 0f1ba9a2cea52896448ef4e14a4cb1880b8e5bee Gitweb: http://git.kernel.org/tip/0f1ba9a2cea52896448ef4e14a4cb1880b8e5bee Author: Heiko Carstens <heiko.carst...@de.ibm.com> AuthorDate: Wed, 7 Jan 2015 10:04:41 +0100 Committer: Ingo Molnar <mi...@kernel.org> CommitDate: Wed, 14 Jan 2015 15:16:21 +0100
softirq/preempt: Add missing current->preempt_disable_ip update While debugging some "sleeping function called from invalid context" bug I realized that the debugging message "Preemption disabled at:" pointed to an incorrect function. In particular if the last function/action that disabled preemption was spin_lock_bh() then current->preempt_disable_ip won't be updated. The reason for this is that __local_bh_disable_ip() will increase preempt_count manually instead of calling preempt_count_add(), which would handle the update correctly. It look like the manual handling was done to work around some lockdep issue. So add the missing update of current->preempt_disable_ip to __local_bh_disable_ip() as well. Signed-off-by: Heiko Carstens <heiko.carst...@de.ibm.com> Signed-off-by: Peter Zijlstra (Intel) <pet...@infradead.org> Cc: Paul E. McKenney <paul...@linux.vnet.ibm.com> Cc: Andrew Morton <a...@linux-foundation.org> Cc: Linus Torvalds <torva...@linux-foundation.org> Link: http://lkml.kernel.org/r/20150107090441.GC4365@osiris Signed-off-by: Ingo Molnar <mi...@kernel.org> --- kernel/softirq.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/kernel/softirq.c b/kernel/softirq.c index 501baa9..b9ae816 100644 --- a/kernel/softirq.c +++ b/kernel/softirq.c @@ -114,8 +114,12 @@ void __local_bh_disable_ip(unsigned long ip, unsigned int cnt) trace_softirqs_off(ip); raw_local_irq_restore(flags); - if (preempt_count() == cnt) + if (preempt_count() == cnt) { +#ifdef CONFIG_DEBUG_PREEMPT + current->preempt_disable_ip = get_parent_ip(CALLER_ADDR1); +#endif trace_preempt_off(CALLER_ADDR0, get_parent_ip(CALLER_ADDR1)); + } } EXPORT_SYMBOL(__local_bh_disable_ip); #endif /* CONFIG_TRACE_IRQFLAGS */ -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
