llvm-project/compiler-rt/lib/stats/stats.cpp

137 lines
3.5 KiB
C++

//===-- stats.cpp ---------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// Sanitizer statistics gathering. Manages statistics for a process and is
// responsible for writing the report file.
//
//===----------------------------------------------------------------------===//
#include "sanitizer_common/sanitizer_common.h"
#include "sanitizer_common/sanitizer_file.h"
#include "sanitizer_common/sanitizer_internal_defs.h"
#if SANITIZER_POSIX
#include "sanitizer_common/sanitizer_posix.h"
#endif
#include "sanitizer_common/sanitizer_symbolizer.h"
#include "stats/stats.h"
#if SANITIZER_POSIX
#include <signal.h>
#endif
using namespace __sanitizer;
namespace {
InternalMmapVectorNoCtor<StatModule **> modules;
StaticSpinMutex modules_mutex;
fd_t stats_fd;
void WriteLE(fd_t fd, uptr val) {
char chars[sizeof(uptr)];
for (unsigned i = 0; i != sizeof(uptr); ++i) {
chars[i] = val >> (i * 8);
}
WriteToFile(fd, chars, sizeof(uptr));
}
void OpenStatsFile(const char *path_env) {
InternalMmapVector<char> path(kMaxPathLength);
SubstituteForFlagValue(path_env, path.data(), kMaxPathLength);
error_t err;
stats_fd = OpenFile(path.data(), WrOnly, &err);
if (stats_fd == kInvalidFd) {
Report("stats: failed to open %s for writing (reason: %d)\n", path.data(),
err);
return;
}
char sizeof_uptr = sizeof(uptr);
WriteToFile(stats_fd, &sizeof_uptr, 1);
}
void WriteModuleReport(StatModule **smodp) {
CHECK(smodp);
const char *path_env = GetEnv("SANITIZER_STATS_PATH");
if (!path_env || stats_fd == kInvalidFd)
return;
if (!stats_fd)
OpenStatsFile(path_env);
const LoadedModule *mod = Symbolizer::GetOrInit()->FindModuleForAddress(
reinterpret_cast<uptr>(smodp));
WriteToFile(stats_fd, mod->full_name(),
internal_strlen(mod->full_name()) + 1);
for (StatModule *smod = *smodp; smod; smod = smod->next) {
for (u32 i = 0; i != smod->size; ++i) {
StatInfo *s = &smod->infos[i];
if (!s->addr)
continue;
WriteLE(stats_fd, s->addr - mod->base_address());
WriteLE(stats_fd, s->data);
}
}
WriteLE(stats_fd, 0);
WriteLE(stats_fd, 0);
}
} // namespace
extern "C"
SANITIZER_INTERFACE_ATTRIBUTE
unsigned __sanitizer_stats_register(StatModule **mod) {
SpinMutexLock l(&modules_mutex);
modules.push_back(mod);
return modules.size() - 1;
}
extern "C"
SANITIZER_INTERFACE_ATTRIBUTE
void __sanitizer_stats_unregister(unsigned index) {
SpinMutexLock l(&modules_mutex);
WriteModuleReport(modules[index]);
modules[index] = 0;
}
namespace {
void WriteFullReport() {
SpinMutexLock l(&modules_mutex);
for (StatModule **mod : modules) {
if (!mod)
continue;
WriteModuleReport(mod);
}
if (stats_fd != 0 && stats_fd != kInvalidFd) {
CloseFile(stats_fd);
stats_fd = kInvalidFd;
}
}
#if SANITIZER_POSIX
void USR2Handler(int sig) {
WriteFullReport();
}
#endif
struct WriteReportOnExitOrSignal {
WriteReportOnExitOrSignal() {
#if SANITIZER_POSIX
struct sigaction sigact;
internal_memset(&sigact, 0, sizeof(sigact));
sigact.sa_handler = USR2Handler;
internal_sigaction(SIGUSR2, &sigact, nullptr);
#endif
}
~WriteReportOnExitOrSignal() {
WriteFullReport();
}
} wr;
} // namespace