On Wed, Aug 23, 2017 at 07:47:14PM +0200, Peter Zijlstra wrote: > Those are fine and are indeed the flush_work() vs work inversion. > > The two straight forward annotations are: > > flush_work(work) process_one_work(wq, work) > A(work) A(work) > R(work) work->func(work); > R(work) > > Which catches: > > Task-1: work: > > mutex_lock(&A); mutex_lock(&A); > flush_work(work);
I'm not sure but, with LOCKDEP_COMPLETE enabled, this issue would automatically be covered w/o additional A(work)/R(work). Right? A(work)/R(work) seem to be used for preventing wait_for_completion() in flush_work() from waiting for the completion forever because of the work using mutex_lock(&A). Am I understanding correctly? If yes, we can use just LOCKDEP_COMPLETE for that purpose. > And the analogous: > > flush_workqueue(wq) process_one_work(wq, work) > A(wq) A(wq) > R(wq) work->func(work); > (wq)
