On Thu, Apr 3, 2008 at 9:51 AM, Jonathan Adams <[EMAIL PROTECTED]> wrote:
>
> I did notice that in .../uts/common/dtrace/dtrace.c you did:
>
> 9580 + case DTRACEACT_BRENDAN:
> 9581 + size = sizeof (uint64_t);
> 9582 + break;
> 9583 +
>
> I think you should be leaving size alone; you aren't returning any data.
That was one of the oddities about implementing an action that doesn't
actually return data out of the kernel. If I didn't set a size here,
the brendan() action wouldn't be consumed (or it would only be
consumed upon hitting a subsequent action.) The main loop in
dt_consume_cpu() (.../lib/libdtrace/common/dt_consume.c) wasn't
running, as it appeared that there was no data to consume:
1578 static int
1579 dt_consume_cpu(dtrace_hdl_t *dtp, FILE *fp, int cpu,
dtrace_bufdesc_t *buf,
1580 dtrace_consume_probe_f *efunc, dtrace_consume_rec_f *rfunc, void *ar
g)
1581 {
1582 dtrace_epid_t id;
1583 size_t offs, start = buf->dtbd_oldest, end = buf->dtbd_size;
[ ... ]
1596 again:
1597 for (offs = start; offs < end; ) {
[ ... ]
1808 if (act == DTRACEACT_BRENDAN) {
1809 if (dt_printf(dtp, fp,
"Tracing... Hit Ctrl-C "
1810 "to end.\n") < 0)
1811 return (-1);
1812 goto nextrec;
1813 }
1814
1815 if (DTRACEACT_ISPRINTFLIKE(act)) {
Of course, this wasn't necessarily the optimal way to implement this.
I could also have implemented it similarly to printf, passing the
string into and back out of the kernel, or I could have done it
entirely in the compiler.
Unfortunately, I had a hard deadline, and I couldn't really ask for
help without tipping my hand. ;-)
Chad
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