On 6/30/21 10:17 PM, Jens Axboe wrote: > On 6/30/21 2:54 PM, Pavel Begunkov wrote: >> Whenever possible we don't want to fallback a request. task_work_add() >> will be fine if the task is exiting, so don't check for PF_EXITING, >> there is anyway only a relatively small gap between setting the flag >> and doing the final task_work_run(). >> >> Also add likely for the hot path. > > I'm not a huge fan of likely/unlikely, and in particular constructs like: > >> - if (test_bit(0, &tctx->task_state) || >> + if (likely(test_bit(0, &tctx->task_state)) || >> test_and_set_bit(0, &tctx->task_state)) >> return 0; > > where the state is combined. In any case, it should be a separate > change. If there's an "Also" paragraph in a patch, then that's also > usually a good clue that that particular change should've been > separate :-) Not sure what's wrong with likely above, but how about drop this one then? -- Pavel Begunkov
