cpu_profiler_guard.h File Reference

Stack-based RAII bracket that pairs every CpuProfiler::begin with a guaranteed end. More...

#include "./macros.h"

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Classes
class	vlink::CpuProfilerGuard
	Scope guard that opens and closes a CpuProfiler active interval. More...

Namespaces
	vlink

Detailed Description

Stack-based RAII bracket that pairs every CpuProfiler::begin with a guaranteed end.

CpuProfilerGuard ties the begin / end pair of a CpuProfiler to scope lifetime so the active interval closes even when the protected region exits through an exception.

RAII pattern

*   scope entry +---------------------------+ scope exit
*   ----------> | CpuProfilerGuard guard(p) | ---------->
*               +-----------+---------------+
*                           | ctor: p->begin()
*                           v
*                       active interval
*                           |
*                           | dtor: p->end()
*                           v
*                       interval closed
* 

The guard accepts a nullptr profiler so call sites can be guarded uniformly while a higher-level switch (typically CpuProfiler::is_global_enabled) decides whether the work is worth measuring.

Example

vlink::CpuProfiler profiler;
 
void process_frame() {
  vlink::CpuProfilerGuard guard(&profiler);   // profiler.begin()
  do_frame_work();
}                                             // profiler.end() on scope exit
 
const double utilisation = profiler.get();

Note

Non-copyable and non-movable; the guard must live on the stack of the protected region.