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tsan: allow usage of global vars with ctors in interceptors 

We allow usage of global/per-thread data with non-trivial ctors/dtors
throughout tsan code base by placing all global/per-thread data into
Context/ThreadState and then explicitly constructing them with
placement new. This greatly simplifies code by restricting the
"linker initialized plague" to only these 2 objects.

Do the same for interceptors data.

This allows to use Vector instead of bunch of hand-written code in:
https://reviews.llvm.org/D39619

Reviewed in: https://reviews.llvm.org/D39721

llvm-svn: 317587
This commit is contained in:
Dmitry Vyukov 2017-11-07 16:31:08 +00:00
parent c6f0ade6c3
commit 3cd4022c39
1 changed files with 32 additions and 13 deletions
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45
compiler-rt/lib/tsan/rtl/tsan_interceptors.cc
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@ -213,8 +213,6 @@ const int SIG_SETMASK = 2;
#define COMMON_INTERCEPTOR_NOTHING_IS_INITIALIZED \
(!cur_thread()->is_inited)
static sigaction_t sigactions[kSigCount];
namespace __tsan {
struct SignalDesc {
bool armed;
@ -233,11 +231,31 @@ struct ThreadSignalContext {
__sanitizer_sigset_t oldset;
};
// The object is 64-byte aligned, because we want hot data to be located in
// a single cache line if possible (it's accessed in every interceptor).
static ALIGNED(64) char libignore_placeholder[sizeof(LibIgnore)];
// InterceptorContext holds all global data required for interceptors.
// It's explicitly constructed in InitializeInterceptors with placement new
// and is never destroyed. This allows usage of members with non-trivial
// constructors and destructors.
struct InterceptorContext {
// The object is 64-byte aligned, because we want hot data to be located
// in a single cache line if possible (it's accessed in every interceptor).
ALIGNED(64) LibIgnore libignore;
sigaction_t sigactions[kSigCount];
#if !SANITIZER_MAC && !SANITIZER_NETBSD
unsigned finalize_key;
#endif
InterceptorContext()
: libignore(LINKER_INITIALIZED) {
}
};
static ALIGNED(64) char interceptor_placeholder[sizeof(InterceptorContext)];
InterceptorContext *interceptor_ctx() {
return reinterpret_cast<InterceptorContext*>(&interceptor_placeholder[0]);
}
LibIgnore *libignore() {
return reinterpret_cast<LibIgnore*>(&libignore_placeholder[0]);
return &interceptor_ctx()->libignore;
}
void InitializeLibIgnore() {
@ -265,10 +283,6 @@ static ThreadSignalContext *SigCtx(ThreadState *thr) {
return ctx;
}
#if !SANITIZER_MAC && !SANITIZER_NETBSD
static unsigned g_thread_finalize_key;
#endif
ScopedInterceptor::ScopedInterceptor(ThreadState *thr, const char *fname,
uptr pc)
: thr_(thr), pc_(pc), in_ignored_lib_(false), ignoring_(false) {
@ -873,7 +887,8 @@ void DestroyThreadState() {
static void thread_finalize(void *v) {
uptr iter = (uptr)v;
if (iter > 1) {
if (pthread_setspecific(g_thread_finalize_key, (void*)(iter - 1))) {
if (pthread_setspecific(interceptor_ctx()->finalize_key,
(void*)(iter - 1))) {
Printf("ThreadSanitizer: failed to set thread key\n");
Die();
}
@ -901,7 +916,7 @@ extern "C" void *__tsan_thread_start_func(void *arg) {
ScopedIgnoreInterceptors ignore;
#if !SANITIZER_MAC && !SANITIZER_NETBSD
ThreadIgnoreBegin(thr, 0);
if (pthread_setspecific(g_thread_finalize_key,
if (pthread_setspecific(interceptor_ctx()->finalize_key,
(void *)GetPthreadDestructorIterations())) {
Printf("ThreadSanitizer: failed to set thread key\n");
Die();
@ -1802,6 +1817,7 @@ namespace __tsan {
static void CallUserSignalHandler(ThreadState *thr, bool sync, bool acquire,
bool sigact, int sig, my_siginfo_t *info, void *uctx) {
sigaction_t *sigactions = interceptor_ctx()->sigactions;
if (acquire)
Acquire(thr, 0, (uptr)&sigactions[sig]);
// Signals are generally asynchronous, so if we receive a signals when
@ -1953,6 +1969,7 @@ TSAN_INTERCEPTOR(int, sigaction, int sig, sigaction_t *act, sigaction_t *old) {
// the signal handler through rtl_sigaction, very bad things will happen.
// The handler will run synchronously and corrupt tsan per-thread state.
SCOPED_INTERCEPTOR_RAW(sigaction, sig, act, old);
sigaction_t *sigactions = interceptor_ctx()->sigactions;
if (old)
internal_memcpy(old, &sigactions[sig], sizeof(*old));
if (act == 0)
@ -2490,6 +2507,8 @@ void InitializeInterceptors() {
mallopt(-3, 32*1024); // M_MMAP_THRESHOLD
#endif
new(interceptor_ctx()) InterceptorContext();
InitializeCommonInterceptors();
#if !SANITIZER_MAC
@ -2641,7 +2660,7 @@ void InitializeInterceptors() {
}
#if !SANITIZER_MAC && !SANITIZER_NETBSD
if (pthread_key_create(&g_thread_finalize_key, &thread_finalize)) {
if (pthread_key_create(&interceptor_ctx()->finalize_key, &thread_finalize)) {
Printf("ThreadSanitizer: failed to create thread key\n");
Die();
}