1 //===-- esan_sideline.h -----------------------------------------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file is a part of EfficiencySanitizer, a family of performance tuners.
12 // Esan sideline thread support.
13 //===----------------------------------------------------------------------===//
15 #ifndef ESAN_SIDELINE_H
16 #define ESAN_SIDELINE_H
18 #include "sanitizer_common/sanitizer_atomic.h"
19 #include "sanitizer_common/sanitizer_internal_defs.h"
23 typedef void (*SidelineFunc)(void *Arg);
25 // Currently only one sideline thread is supported.
26 // It calls the SidelineFunc passed to launchThread once on each sample at the
27 // given frequency in real time (i.e., wall clock time).
28 class SidelineThread {
30 // We cannot initialize any fields in the constructor as it will be called
31 // *after* launchThread for a static instance, as esan.module_ctor is called
32 // before static initializers.
36 // To simplify declaration in sanitizer code where we want to avoid
37 // heap allocations, the constructor and destructor do nothing and
38 // launchThread and joinThread do the real work.
39 // They should each be called just once.
40 bool launchThread(SidelineFunc takeSample, void *Arg, u32 FreqMilliSec);
43 // Must be called from the sideline thread itself.
44 bool adjustTimer(u32 FreqMilliSec);
47 static int runSideline(void *Arg);
48 static void registerSignal(int SigNum);
49 static void handleSidelineSignal(int SigNum, void *SigInfo, void *Ctx);
52 SidelineFunc sampleFunc;
56 atomic_uintptr_t SidelineExit;
61 #endif // ESAN_SIDELINE_H