On Sat, 21 Mar 2009 07:51:41 -0400 "Frank Ch. Eigler" <f...@redhat.com> wrote:
> Hi - > > On Sat, Mar 21, 2009 at 04:19:54AM -0700, Andrew Morton wrote: > > [...] > > > Utrace is very much tracing material - without the ftrace plugin the > > > whole utrace machinery is just something that provides a _ton_ of > > > hooks to something entirely external: SystemTap mainly. > > > > Roland's changelogs don't mention systemtap at all afacit. > > That was, umm, major information lossage. > > There have been many mixed messages from LKML on the topic - sometimes > mentioning systemtap is forbidden, other times necessary. Sorry about > that. heh. We all love systemtap and want it to get better. > There are several non-systemtap clients in existence or under > development. You've may have heard of the ptrace cleanup, a > multi-client ptrace replacement, an on-the-fly core dumper, the ftrace > widget, user-space probes. All of these should have somewhat > compelling non-systemtap uses, if that's an important criterion. Well I dunno. You guys are closer to this than I am, but I'd have thought that systemtap is the main game here, and most/all of the above is just fluff. IOW, "this helps systemtap" is sufficient reason for merging a kernel change. For sufficiently large values of "help", and sufficiently small values of "eww", of course. I have strong memories of being traumatised by reading the uprobes code. What's the story on all of that nowadays? > > > Actually it seems that the whole utrace-ftrace thing is a big > > distraction and could/should just be omitted. This is a systemtap > > feature and should be viewed as such. [...] > > utrace is a better way to perform user thread management than what is > there now, and the utrace-ftrace widget shows how to *hook* thread > events such as syscalls in a lighter weight / more managed way than > the first one proposed. (That's one reason we've been participating > in the ftrace discussions.) Of course it can be made to use the fine > syscall pretty-printing code recently added. eh. Boring. Let's fix systemtap?
