Hi David, Since we have some discussion about the atomic operations now, I changed the commit message from "C11 atomics"(which has been widely used in previous commit) to "GCC atomic built-ins". What's your opinion about whether keeping the previous message for the consistency or using the new description?
Joyce > -----Original Message----- > From: Honnappa Nagarahalli <honnappa.nagaraha...@arm.com> > Sent: Thursday, July 1, 2021 6:41 AM > To: Tyler Retzlaff <roret...@linux.microsoft.com> > Cc: tho...@monjalon.net; Joyce Kong <joyce.k...@arm.com>; > dev@dpdk.org; david.march...@redhat.com; > step...@networkplumber.org; olivier.m...@6wind.com; > andrew.rybche...@oktetlabs.ru; harry.van.haa...@intel.com; Ruifeng > Wang <ruifeng.w...@arm.com>; nd <n...@arm.com>; techbo...@dpdk.org; > nd <n...@arm.com> > Subject: RE: [dpdk-dev] [PATCH v2 0/8] use GCC's C11 atomic builtins for test > > <snip> > > > > > > > > > > > > > > As I mentioned earlier in this thread, GCC supports 2 types of > > > > > atomics. "Use GCC atomic builtins" does not help distinguish > > > > > between them. In "GCC's C11 atomic builtins" - "C11" indicates > > > > > which atomics we are using, "atomic builtins" indicates that we > > > > > are NOT using APIs from stdatomic.h > > > > > > > > if you need a term to distinguish the two sets of atomics in gcc > > > > you can qualify it with "Memory Model Aware" which is straight > > > > from the gcc > > manual. > > > "Memory model aware" sounds too generic. The same page [1] also > > > makes > > it clear that the built-in functions match the requirements for the > > C11 memory model. > > > > allow me to put your interpretation of the manual that you linked side > > by side with what the manual text actually says verbatim. > > > > your text from above > > "built-in functions match the requirements for the C11 memory model." > > > > the actual text from your link > > "built-in functions approximately match the requirements for the > > C++11 memory model." > > > > * you've chosen to drop approximately from the wording to try and make > > your argument. > I am not sure how this makes a difference to our arguments. For ex: there > are no other built in functions that "exactly" match the C++11 memory model > supported by GCC. > > > > > * you've also chosen to substitute C11 in place of C++11. again > > presumably for the same reason. > > > > in fact the entire page does not mention C11 even once, it also goes > > on to highlight a specific deviation from C++11 with this excerpt > > "because of a deficiency in C++11's semantics for > memory_order_consume" > I do not have a problem to call it C++11. IMO, calling it "GCC's C++11 ..." > will > address this deviation and the approximation. > > > > > > There are also several patches merged in the past which do not use > > > the term > > "memory model aware". I would prefer to be consistent. > > > > i prefer the history represent the change. that previous submitters > > and reviewers lacked precision is not my concern nor is consistency a > > reason to continue documenting history incorrectly. > Ok. As I mentioned, it is just my preference. > > > > > i'm waiting to ack the change, it's up to you. you've already spent > > more time arguing than it would have taken to submit a v2 correcting the > problem. > I am not arguing for the sake of arguing. You are trying to correct few > mistakes here (I truly appreciate that) and I am trying to explain my POV and > making corrections as needed. I am sure we will conclude soon. > > > > > > > > > [1] > > > https://gcc.gnu.org/onlinedocs/gcc/_005f_005fatomic-Builtins.html
