On Mon, Oct 12, 2009 at 03:13:51PM -0400, Masami Hiramatsu wrote:Frederic Weisbecker wrote:The conflict issue might not be obvious for a user desperately trying to set
a kprobe. Even for other failcases, it might not be obvious (blacklisted
symbols, syntax errors...)
May be should you improve the error granularity and print a KERN_DEBUG
message?
Agreed, and kprobes error handling should be improved too (in the most cases,
it just returns -EINVAL).
Thank you.
And btw, I'm enable to create a probe, neither through ftrace nor perf:
$ sudo ./perf probe -P 'p:sys_close sys_close $retval'
Adding new event: p:sys_close sys_close+0 $retval
Error: Failed to create event: Invalid argument
# echo 'p:sys_open sys_open $retval'> /debug/tracing/kprobe_events
bash: echo: write error : Invalid argument
I suspect I missed something very obvious with the syntax :)
I've applied your patches in:
git://git.kernel.org/pub/scm/linux/kernel/git/frederic/random-tracing.git
tracing/kprobes
Thanks.