Messages in this thread | | | Date | Mon, 11 Aug 2008 14:29:38 -0400 | From | Mathieu Desnoyers <> | Subject | Re: [PATCH 4/5] kmemtrace: SLUB hooks. |
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* Christoph Lameter (cl@linux-foundation.org) wrote: > Steven Rostedt wrote: > > > The kmemtrace_mark_alloc_node itself is an inline function, which calls > > another inline function "trace_mark" which is designed to test a > > read_mostly variable, and will do an "unlikely" jmp if the variable is > > set (which it is when tracing is enabled), to the actual function call. > > > > There should be no extra function calls when this is configured on but > > tracing disabled. We try very hard to keep the speed of the tracer as > > close to a non tracing kernel as possible when tracing is disabled. > > Makes sense. But then we have even more code bloat because of the tests that > are inserted in all call sites of kmalloc. >
The long-term goal is to turn the tests into NOPs, but only once we get gcc support.
Mathieu
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