> -----Original Message----- > Pawe? > > > On Mon, Sep 29, 2014 at 10:11:38AM +0000, Wodkowski, PawelX wrote: > > > > > > > > > > Image how you will be damned by someone that not even notice you > > change > > > > > and he Is managing some kind of resource based on returned number of > > > > > set/canceled timers. If you suddenly start returning negative values > > > > > how > > those > > > > > application will behave? Silently changing returned value domain is > > > > > evil in > > its > > > > > pure form. > > > > > > > > As I can see the impact is very limited. > > > > > > It is small impact to DPDK but can be huge to user application: > > > > This is why we traditionally have in the release-notes for each release a > > section dedicated to calling out changes from one release to another. [See > > http://dpdk.org/doc/intel/dpdk-release-notes-1.7.0.pdf section 5]. Since > > from release-to-release there are generally only a couple of changes - > > though our next release may be a little different - the actual changes are > > clear enough to read about without wading through pages of documentation. > I > > thinking calling out the change in both the release notes and the API docs > > is sufficient even for a change like this. > > > > Basically, I wouldn't let API stability factor in too much in trying to get > > a proper fix for this issue. > > > > /Bruce > > > > Summarizing all proposed solutions and to be able to produce final patch - > what > Is desired behavior after fix? > > 1. do we leave as is in Patch v2: > 1.1 if canceling from other thread - if one of the alarms is executing, wait > to > finish its execution and then cancel any rearmed alarms. > 1.2 if canceling from alarm handler and one of the alarms to cancel is this > executing callback do no wait for it to finish and cancel anything else. > > in both cases return number of canceled callbacks. > > 2. Do exactly like in 1. but return -EINPROGRESS instead of canceled alarms > if one of the alarms to cancel is currently executing callback from alarm > thread > (information about number of canceled alarms will be lost).
Or instead of returning -EINPROGRESS set errno to EINPROGRESS (replace returning error value by setting errno and function can always return number of canceled callbacks - in error condition 0)? > > 3. refuse to cancel anything if canceling currently executing alarm from alarm > callback and return -EINPROGRESS otherwise do like in 1.1. > > 4. Implement behaviour 1/2/3 (which?) and add API call to interrogate list of > alarms and retrun state of given alarms(s). > > 5. other solutions? > > Pawel
