Messages in this thread | | | Subject | Re: [PATCH][RFC] kprobes: Add user entry-handler in kretprobes | From | Jim Keniston <> | Date | Thu, 15 Nov 2007 16:07:24 -0800 |
| |
On Thu, 2007-11-15 at 20:30 +0530, Abhishek Sagar wrote: > On Nov 15, 2007 4:21 AM, Jim Keniston <jkenisto@us.ibm.com> wrote: > > 2. Simplify the task of correlating data (e.g., timestamps) between > > function entry and function return. > > Would adding of data and len fields in ri help? Instead of "pouching" > data in one go at registration time, this would let user handlers do > the allocation
Yes and no. Adding just a data field -- void*, or maybe unsigned long long so it's big enought to accommodate big timestamps -- would be a big improvement on your current proposal. That would save the user the drudgery of mapping the ri pointer to his/her per-instance data. There's plenty of precedent for passing "private_data" values to callbacks.
I don't think a len field would help much. If such info were needed, it could be stored in the data structure pointed to by the data field.
I still don't think "letting [i.e., requiring that] user handlers do the allocation" is a win. I'm still interested to see how this plays out in real examples.
> and allow them to use different kinds of data > structures per-instance.
I haven't been able to think of any scenarios where this would be useful. A "data pouch" could always contain a union, FWIW.
> > - Abhishek Sagar
Jim
- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |