Date: Fri, 17 Aug 2018 09:35:14 -0400 From: Ash Gokhale <ashfixit@gmail.com> To: freebsd-dtrace@freebsd.org Cc: khanzf@gmail.com Subject: Re: Filter out dtrace(1) probes Message-ID: <CAHpe%2B0bF4DrQhDmrU17Y01Y0Z6cvh8mN6HXbQMk2R=OTd%2B8C_A@mail.gmail.com> In-Reply-To: <54B93C32-7672-4A54-9272-F3F0CF5B38BD@gmail.com> References: <CAFd4kYDZLnNtkWiQ56dzzn11Lh7FKAK-xCrs91fNQGPGeYbC=A@mail.gmail.com> <54B93C32-7672-4A54-9272-F3F0CF5B38BD@gmail.com>
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>
> > On 17 Aug 2018, at 00:49, Farhan Khan <khanzf@gmail.com> wrote:
> >
> > Hi all,
> >
> > Is it possible to filter out probes?
> > For example, if I did:
> >
> > dtrace -n 'fbt:kernel::entry { something_here }'
>
Sure, try extending this:
dtrace -n 'fbt:kernel:read*:entry /probefunc != "read_cpu_time" &&
probefunc != "readdep"/ {@[probefunc]=count();}'
Altough fbt::kernel::entry is going to mach a _lot_ of probes. Unless you
are looking for a simple kernel function use count this is probably going
to overload the data collection plumbing. You should probably narrow your
probe list based on what you are hunting. Also fbt:kernel::entry is only
going to get core freebsd calls, excluding all loadable modules (zfs.ko
..) . if you really want all kernel functions, use fbt:::entry, as blank
entries are wildcards.
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