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    SubjectRe: [PATCH 0/18] Allow different tracers to be compiled independently
    On Tue, Mar 23, 2010 at 01:32:02AM +0100, Jan Kara wrote:
    > Hi,
    > currently, when one tracer is selected, most of tracepoints for other
    > tracers also gets pulled into the kernel. So for example it's not possible
    > to enable BLK_DEV_IO_TRACE without polluting slab allocation paths with
    > tracepoint checks (see changelog of patch 01). This patch set adds a
    > possibility for each set of trace points to be compile-enabled separately.
    > The first patch contains the necessary magic in linux/tracepoint.h. Other
    > patches just tell tracing framework about correspoding config options
    > and possibly introduce them if they did not exist before.
    > The patches in this patch set are actually completely independent so
    > they can be merged via respective subsystem trees. But changes are rather
    > tiny so I don't expect much conflicts...
    > Honza

    (Adding more people in Cc)

    I don't know. Yeah this first looks like a good idea but once
    CONFIG_EVENT_TRACING is enabled, each tracepoint is a lightweight
    thing and induce a tiny overhead, probably hard to notice, and
    this is going to be even more the case after the jmp label
    optimization patches.

    I liked the fact we had a general tracing kernel once the above
    config is selected. And we don't bother telling people that to
    use tool X you need CONFIG_EVENT_Y, and you need to rebuild your
    kernel, etc...

    I wonder if this is going to be a win.

     \ /
      Last update: 2010-03-23 02:07    [W:0.023 / U:0.124 seconds]
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