On Wed, Oct 30, 2024 at 10:47:55AM -0700, Josh Poimboeuf wrote: > > Moving from per-cpu to per-task makes this cookie task-specific and not > > global anymore, I don't think we want this for a stack walking > > infrastructure meant to be used by various tracers. Also a global cookie > > is more robust and does not depend on guaranteeing that all the > > trace data is present to guarantee current thread ID accuracy and > > thus that cookies match between deferred unwind request and their > > fulfillment. > > I don't disagree. What I meant was, on entry (or exit), increment the > task cookie *with* the CPU bits included. > > Or as you suggested previously, the "cookie" just be a struct with two > fields: CPU # and per-task entry counter.
Never mind, that wouldn't work... Two tasks could have identical per-task counters while being scheduled on the same CPU. -- Josh
