Messages in this thread | | | Date | Tue, 23 Jan 2007 20:29:09 -0800 | From | Andrew Morton <> | Subject | Re: [PATCH 2/2] lockdep reentrancy |
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On Tue, 16 Jan 2007 12:56:31 -0500 Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> wrote:
> Here is a patch to lockdep.c so it behaves correctly when a kprobe breakpoint is > put on a marker within hardirq tracing functions as long as the marker is within > the lockdep_recursion incremented boundaries. It should apply on > 2.6.20-rc4-git3. > > Mathieu > > Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> > > > @@ -1841,33 +1843,36 @@ void trace_hardirqs_on(void)
You lost the patch headers.
> struct task_struct *curr = current; > unsigned long ip; > > if (unlikely(!debug_locks || current->lockdep_recursion)) > return; > > + current->lockdep_recursion++; > + barrier();
Why can't we use lockdep_off() here?
> if (DEBUG_LOCKS_WARN_ON(unlikely(!early_boot_irqs_enabled))) > - return; > + goto end; > > if (unlikely(curr->hardirqs_enabled)) { > debug_atomic_inc(&redundant_hardirqs_on); > - return; > + goto end; > } > /* we'll do an OFF -> ON transition: */ > curr->hardirqs_enabled = 1; > ip = (unsigned long) __builtin_return_address(0); > > if (DEBUG_LOCKS_WARN_ON(!irqs_disabled())) > - return; > + goto end; > if (DEBUG_LOCKS_WARN_ON(current->hardirq_context)) > - return; > + goto end; > /* > * We are going to turn hardirqs on, so set the > * usage bit for all held locks: > */ > if (!mark_held_locks(curr, 1, ip)) > - return; > + goto end; > /* > * If we have softirqs enabled, then set the usage > * bit for all held locks. (disabled hardirqs prevented > @@ -1875,11 +1880,14 @@ void trace_hardirqs_on(void) > */ > if (curr->softirqs_enabled) > if (!mark_held_locks(curr, 0, ip)) > - return; > + goto end; > > curr->hardirq_enable_ip = ip; > curr->hardirq_enable_event = ++curr->irq_events; > debug_atomic_inc(&hardirqs_on_events); > +end: > + barrier(); > + current->lockdep_recursion--;
lockdep_on()?
> } > > EXPORT_SYMBOL(trace_hardirqs_on); > @@ -1888,14 +1896,17 @@ void trace_hardirqs_off(void) > { > struct task_struct *curr = current; > > if (unlikely(!debug_locks || current->lockdep_recursion)) > return; > > + current->lockdep_recursion++; > + barrier();
lockdep_off()?
> if (DEBUG_LOCKS_WARN_ON(!irqs_disabled())) > - return; > + goto end; > > if (curr->hardirqs_enabled) { > /* > @@ -1910,6 +1921,9 @@ void trace_hardirqs_off(void) > debug_atomic_inc(&hardirqs_off_events); > } else > debug_atomic_inc(&redundant_hardirqs_off); > +end: > + barrier(); > + current->lockdep_recursion--;
lockdep_on()? - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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