| Message ID | 1513062681-5995-1-git-send-email-byungchul.park@lge.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
+cc david@fromorbit.com +cc tytso@mit.edu +cc willy@infradead.org +cc torvalds@linux-foundation.org +cc amir73il@gmail.com On 12/12/2017 4:11 PM, Byungchul Park wrote: > At the moment, it's rather premature to enable > CONFIG_LOCKDEP_CROSSRELEASE and CONFIG_LOCKDEP_COMPLETIONS by default, > because we face a lot of false positives for now since all locks and > waiters are not classified properly yet. > > Until most of them get annotated properly, it'd be better to be optional. > > Signed-off-by: Byungchul Park <byungchul.park@lge.com> > --- > lib/Kconfig.debug | 11 +++++++---- > 1 file changed, 7 insertions(+), 4 deletions(-) > > diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug > index 2689b7c..bc099f1 100644 > --- a/lib/Kconfig.debug > +++ b/lib/Kconfig.debug > @@ -1092,8 +1092,6 @@ config PROVE_LOCKING > select DEBUG_MUTEXES > select DEBUG_RT_MUTEXES if RT_MUTEXES > select DEBUG_LOCK_ALLOC > - select LOCKDEP_CROSSRELEASE > - select LOCKDEP_COMPLETIONS > select TRACE_IRQFLAGS > default n > help > @@ -1164,7 +1162,9 @@ config LOCK_STAT > (CONFIG_LOCKDEP defines "acquire" and "release" events.) > > config LOCKDEP_CROSSRELEASE > - bool > + bool "Lock debugging: enable cross-locking checks in lockdep" > + depends on PROVE_LOCKING > + default n > help > This makes lockdep work for crosslock which is a lock allowed to > be released in a different context from the acquisition context. > @@ -1174,7 +1174,10 @@ config LOCKDEP_CROSSRELEASE > detector, lockdep. > > config LOCKDEP_COMPLETIONS > - bool > + bool "Lock debugging: allow completions to use deadlock detector" > + depends on PROVE_LOCKING > + select LOCKDEP_CROSSRELEASE > + default n > help > A deadlock caused by wait_for_completion() and complete() can be > detected by lockdep using crossrelease feature. >
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index 2689b7c..bc099f1 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -1092,8 +1092,6 @@ config PROVE_LOCKING select DEBUG_MUTEXES select DEBUG_RT_MUTEXES if RT_MUTEXES select DEBUG_LOCK_ALLOC - select LOCKDEP_CROSSRELEASE - select LOCKDEP_COMPLETIONS select TRACE_IRQFLAGS default n help @@ -1164,7 +1162,9 @@ config LOCK_STAT (CONFIG_LOCKDEP defines "acquire" and "release" events.) config LOCKDEP_CROSSRELEASE - bool + bool "Lock debugging: enable cross-locking checks in lockdep" + depends on PROVE_LOCKING + default n help This makes lockdep work for crosslock which is a lock allowed to be released in a different context from the acquisition context. @@ -1174,7 +1174,10 @@ config LOCKDEP_CROSSRELEASE detector, lockdep. config LOCKDEP_COMPLETIONS - bool + bool "Lock debugging: allow completions to use deadlock detector" + depends on PROVE_LOCKING + select LOCKDEP_CROSSRELEASE + default n help A deadlock caused by wait_for_completion() and complete() can be detected by lockdep using crossrelease feature.
At the moment, it's rather premature to enable CONFIG_LOCKDEP_CROSSRELEASE and CONFIG_LOCKDEP_COMPLETIONS by default, because we face a lot of false positives for now since all locks and waiters are not classified properly yet. Until most of them get annotated properly, it'd be better to be optional. Signed-off-by: Byungchul Park <byungchul.park@lge.com> --- lib/Kconfig.debug | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-)