On Tue, Oct 06, 2020 at 02:40:20PM +0800, Junchang Wang wrote:
> On Mon, Oct 05, 2020 at 03:12:22PM -0700, Paul E. McKenney wrote:
> >On Sat, Oct 03, 2020 at 09:19:25AM -0700, Paul E. McKenney wrote:
> >> On Sat, Oct 03, 2020 at 12:28:47PM +0800, Junchang Wang wrote:
> >
> >[ . . . ]
> >
> >> But sadly, this change does not fix this bug:
> >>
> >> $ ./hash_bkt_hazptr --schroedinger --nreaders 1 --duration 1000 --updatewait 0 --nbuckets 8192 --elems/writer 8192
> >> Segmentation fault (core dumped)
> >>
> >> Can't have everything. ;-)
> >>
> >> It appears that hashtorture manages to fail to call the per-thread
> >> hazard-pointers initialization on some paths, so it is no surprise
> >> that Junchang's fix doesn't fix this bug.
> >
> > Thanx, Paul
> >
> >------------------------------------------------------------------------
> >
> >commit 2533decebb7fca65d2860174246966f5ed255dd0
> >Author: Paul E. McKenney <paulmck@xxxxxxxxxx>
> >Date: Mon Oct 5 15:10:03 2020 -0700
> >
> > datastruct/hash: Add missing hash_register_thread()
> >
> > The zoo_test() function was missing the hash_register_thread() invocation
> > that is required to make hazard pointers work correctly. The lack
> > of this invocation results in a segmentation violation. This commit
> > therefore adds this call.
> >
> > Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxx>
> >
>
> Hi Paul,
>
> This patch fixes the bug, and now "./hash_bkt_hazptr --schroedinger" works
> correctly on my servers. Thanks a lot.
Thank you for testing! May I apply your Tested-by?
Thanx, Paul
> --Junchang
>
> >diff --git a/CodeSamples/datastruct/hash/hashtorture.h b/CodeSamples/datastruct/hash/hashtorture.h
> >index 6d30cb8..7d43e11 100644
> >--- a/CodeSamples/datastruct/hash/hashtorture.h
> >+++ b/CodeSamples/datastruct/hash/hashtorture.h
> >@@ -1211,6 +1211,7 @@ void zoo_test(void)
> > for (i = 0; i < nupdaters * elperupdater; i++) {
> > sprintf(&zoo_names[ZOO_NAMELEN * i], "a%ld", i);
> > }
> >+ hash_register_thread();
> >
> > zhep = malloc(sizeof(*zhep));
> > BUG_ON(!zhep);
