[NFS-Ganesha-Devel] Re: Extra mdcache_lru_unref_chunk path

The core I have in the message thread: https://lists.nfs-ganesha.org/archives/list/devel@lists.nfs-ganesha.org/t... was with 2.7.5 with the below change already applied. The core is very reproducible.

The window that is fixed by this change - does it also exist for the case where we transition to the next chunk on the last line in mdcache_readdir_chunked. Read_lock. The first chunk is populated, and we read the entries from that chunk. Then we transition to the next chunk. The next chunk is not populated, he have a ref count on the chunk, and we continue to hold the ref across the lock drop. Thanks, Vandana if (look_ck == 0 || !mdcache_avl_lookup_ck(directory, look_ck, &dirent)) { fsal_status_t status; /* This starting position isn't in our cache... * Go populate the cache and process from there. */ if (!has_write) { /* Upgrade to write lock and retry just in case * another thread managed to populate this cookie * in the meantime. */ PTHREAD_RWLOCK_unlock(&directory->content_lock); PTHREAD_RWLOCK_wrlock(&directory->content_lock); has_write = true; /* We have a ref on chunk; don't null it out */ goto again; } ???On 7/11/19, 8:09 AM, "Daniel Gryniewicz" <dang(a)redhat.com&gt; wrote: Okay, this is a simple fix. It should not, in fact, be holding a ref across the lock drop, since we are throwing that chunk away anyway. The unref was in the wrong location. https://review.gerrithub.io/c/ffilz/nfs-ganesha/+/461446 Daniel