This is an automated email from the git hooks/post-receive script. It was generated because a ref change was pushed to the repository containing the project "MPICH primary repository". The branch, master has been updated via a5686ec3c42f0357119cab7f21df46389c7acec8 (commit) from 94e8a8058e775a224367d2eeffcd73c905d7e071 (commit) Those revisions listed above that are new to this repository have not appeared on any other notification email; so we list those revisions in full, below. - Log ----------------------------------------------------------------- http://git.mpich.org/mpich.git/commitdiff/a5686ec3c42f0357119cab7f21df46389c... commit a5686ec3c42f0357119cab7f21df46389c7acec8 Author: Rob Latham <[email protected]> Date: Thu Mar 26 14:15:07 2015 -0500 Revert "When decrementing a ref-count to 0, do not bother with atomics." This reverts commit 7a36603163cd917fe89a39cad668e5a7b6f917cb. At one point (circa MPICH2-1.5) this clever optimization behaved as expected. Once ported forward to more recent MPICH, segfaults on trivial MPI applications. Closes: #2217 Reopens: #1835 Signed-off-by: Ken Raffenetti <[email protected]> diff --git a/src/include/mpihandlemem.h b/src/include/mpihandlemem.h index 1ab6752..1847031 100644 --- a/src/include/mpihandlemem.h +++ b/src/include/mpihandlemem.h @@ -300,25 +300,10 @@ typedef OPA_int_t MPIU_Handle_ref_count; MPIU_HANDLE_LOG_REFCOUNT_CHANGE(objptr_, "incr"); \ MPIU_HANDLE_CHECK_REFCOUNT(objptr_,"incr"); \ } while (0) - -/* Special optimization: when the reference count touches one, we are - * about to free the object. In this case, it is illegal for another - * thread to either increment the reference (i.e., create a new object - * that depends on this object) or decrement the references (i.e., - * free the object simultaneously). We, however, have to ensure that - * our load is atomic. OPA does this for us, while optimizing it to a - * simple load for cases where the architecture already provides us - * with load atomicity and no need for load memory barriers. */ #define MPIU_Object_release_ref_always(objptr_,inuse_ptr) \ do { \ - if (likely(OPA_load_int((objptr_)->ref_count.v) == 1)) { \ - (objptr_)->ref_count.v = 0; \ - *(inuse_ptr) = 0; \ - } \ - else { \ - int got_zero_ = OPA_decr_and_test_int(&((objptr_)->ref_count)); \ - *(inuse_ptr) = got_zero_ ? 0 : 1; \ - } \ + int got_zero_ = OPA_decr_and_test_int(&((objptr_)->ref_count)); \ + *(inuse_ptr) = got_zero_ ? 0 : 1; \ MPIU_HANDLE_LOG_REFCOUNT_CHANGE(objptr_, "decr"); \ MPIU_HANDLE_CHECK_REFCOUNT(objptr_,"decr"); \ } while (0) ----------------------------------------------------------------------- Summary of changes: src/include/mpihandlemem.h | 19 ++----------------- 1 files changed, 2 insertions(+), 17 deletions(-) hooks/post-receive -- MPICH primary repository