Re: [PATCH v11 04/11] tracing: wprobe: Add watchpoint probe event based on hardware breakpoint
Steven Rostedt <[email protected]>
| Newsgroups | gmane.linux.documentation,gmane.linux.kernel,gmane.linux.kernel.perf.user |
|---|---|
| Message-ID | <[email protected]> |
On Wed, 5 Aug 2026 21:39:09 +0200 Peter Zijlstra <[email protected]> wrote: > > > This seems limited to kernel addresses only? Should not also userspace > > > addresses be supported? > > > > Hmm, how would that work? The address is global for all tasks, so if you > > add a user space address, what task would that be for? The one writing the > > probe? > > Schedule the watchpoint along with the task of course. Given there is > breakpoint/perf integration this should be trivial. I meant, what task is it attached to? Usually the way a probe works is to create the probe and then enable it. # cd /sys/kernel/tracing # echo 'w:my_jiffies w@jiffies:8 value=+0($addr)' >> dynamic_events # echo 1 > events/wprobes/my_jiffies/enable If the address is in user space, which task would that address be for? What would the API look like? Should we add a pid to that for a specific task? Maybe use zero for current task? -- Steve