lkml.org 
[lkml]   [2008]   [Nov]   [13]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH 4/7] kprobes: Support probing module __exit function
On Thu, Nov 13, 2008 at 04:27:39PM -0800, Andrew Morton wrote:
> On Tue, 11 Nov 2008 15:56:58 -0500
> Masami Hiramatsu <mhiramat@redhat.com> wrote:
>
> > @@ -69,9 +69,6 @@ struct kprobe {
> > /* list of kprobes for multi-handler support */
> > struct list_head list;
> >
> > - /* Indicates that the corresponding module has been ref counted */
> > - unsigned int mod_refcounted;
> > -
> > /*count the number of times this probe was temporarily disarmed */
> > unsigned long nmissed;
> >
> > @@ -103,8 +100,19 @@ struct kprobe {
> >
> > /* copy of the original instruction */
> > struct arch_specific_insn ainsn;
> > +
> > + /* Indicates various status flags */
> > + u32 flags;
> > };
> >
> > +/* Kprobe status flags */
> > +#define KPROBE_FLAG_GONE 1 /* breakpoint has already gone */
> > +
> > +static inline int kprobe_gone(struct kprobe *p)
> > +{
> > + return p->flags & KPROBE_FLAG_GONE;
> > +}
>
> If we're not going to use atomic bitops on kprobe.flags then
> modifications to that member will require that the caller hold a lock.
> The comment above that member should describe its locking protocol. It
> seems that it is kprobe_mutex, so...
>
> --- a/include/linux/kprobes.h~kprobes-support-probing-module-__exit-function-fix
> +++ a/include/linux/kprobes.h
> @@ -101,7 +101,7 @@ struct kprobe {
> /* copy of the original instruction */
> struct arch_specific_insn ainsn;
>
> - /* Indicates various status flags */
> + /* Indicates various status flags. Protected by kprobe_mutex. */
> u32 flags;
> };
>
> _
>
>
> yes?

Right, setting and resetting is done under the kprobe_mutex.

Ananth


\
 
 \ /
  Last update: 2008-11-14 05:55    [W:0.043 / U:0.700 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site