Messages in this thread |  | | Date | Tue, 5 Nov 2013 20:24:01 +0100 | From | Oleg Nesterov <> | Subject | Re: [PATCHSET 00/13] tracing/uprobes: Add support for more fetch methods (v6) |
| |
On 11/05, Oleg Nesterov wrote: > > As for "-= tu->offset"... Can't we avoid it? User-space needs to calculate > the "@" argument anyway, why it can't also substruct this offset? > > Or perhaps we can change parse_probe_arg("@") to update "param" ? Yes, > in this case it needs another argument, not sure...
Or,
> + if (is_ret_probe(tu)) { > + saved_ip = instruction_pointer(regs); > + instruction_pointer_set(func); > + } > store_trace_args(...); > + if (is_ret_probe(tu)) > + instruction_pointer_set(saved_ip);
we can put "-= tu->offset" here.
> although not pretty.
Yes.
Or. Perhaps we can leave "case '@'" in parse_probe_arg() and FETCH_MTD_memory alone. You seem to agree that "absolute address" can be useful anyway.
Instead, perhaps we can add FETCH_MTD_memory_do_fancy_addr_translation, and, say, the new "case '*'" in parse_probe_arg() should add all the neccessary info as f->data (like, say, FETCH_MTD_symbol).
But, just in case, I do not have a strong opinion. Just I think it is better to discuss every choice we have.
Oleg.
|  |