From 27d4ca2df9333ac38046628f7cae752b00077892 Mon Sep 17 00:00:00 2001 From: Clement Courbet Date: Tue, 15 May 2018 07:35:21 +0000 Subject: [PATCH] [llvm-exegesis] Check perf event validity. This was part of https://reviews.llvm.org/D46821. Authored by Guillaume Chatelet llvm-svn: 332330 --- llvm/tools/llvm-exegesis/lib/PerfHelper.cpp | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/llvm/tools/llvm-exegesis/lib/PerfHelper.cpp b/llvm/tools/llvm-exegesis/lib/PerfHelper.cpp index d1dfeac..f164e3d 100644 --- a/llvm/tools/llvm-exegesis/lib/PerfHelper.cpp +++ b/llvm/tools/llvm-exegesis/lib/PerfHelper.cpp @@ -15,6 +15,7 @@ #include "perfmon/pfmlib.h" #include "perfmon/pfmlib_perf_event.h" #endif +#include namespace exegesis { namespace pfm { @@ -88,6 +89,7 @@ llvm::StringRef PerfEvent::getPfmEventString() const { #ifdef HAVE_LIBPFM Counter::Counter(const PerfEvent &Event) { + assert(Event.valid()); const pid_t Pid = 0; // measure current process/thread. const int Cpu = -1; // measure any processor. const int GroupFd = -1; // no grouping of counters. @@ -108,8 +110,10 @@ void Counter::stop() { ioctl(FileDescriptor, PERF_EVENT_IOC_DISABLE, 0); } int64_t Counter::read() const { int64_t Count = 0; ssize_t ReadSize = ::read(FileDescriptor, &Count, sizeof(Count)); - if (ReadSize != sizeof(Count)) + if (ReadSize != sizeof(Count)) { + Count = -1; llvm::errs() << "Failed to read event counter\n"; + } return Count; } -- 2.7.4