On Wed, 18 Oct 2017, Byungchul Park wrote: > #ifdef CONFIG_LOCKDEP_CROSSRELEASE > +#ifdef CONFIG_CROSSRELEASE_STACK_TRACE > #define MAX_XHLOCK_TRACE_ENTRIES 5 > +#else > +#define MAX_XHLOCK_TRACE_ENTRIES 1 > +#endif > > /* > * This is for keeping locks waiting for commit so that true dependencies > diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c > index e36e652..5c2ddf2 100644 > --- a/kernel/locking/lockdep.c > +++ b/kernel/locking/lockdep.c > @@ -4863,8 +4863,13 @@ static void add_xhlock(struct held_lock *hlock) > xhlock->trace.nr_entries = 0; > xhlock->trace.max_entries = MAX_XHLOCK_TRACE_ENTRIES; > xhlock->trace.entries = xhlock->trace_entries; > +#ifdef CONFIG_CROSSRELEASE_STACK_TRACE > xhlock->trace.skip = 3; > save_stack_trace(&xhlock->trace); > +#else > + xhlock->trace.nr_entries = 1; > + xhlock->trace.entries[0] = hlock->acquire_ip; > +#endif Hmm. Would it be possible to have this switchable at boot time via a command line parameter? So in case of a splat with no stack trace, one could just reboot and set something like 'lockdep_fullstack' on the kernel command line to get the full data without having to recompile the kernel. Thanks, tglx -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>
