@@ -395,6 +395,7 @@ gprof="no"
debug_tcg="no"
debug="no"
sanitizers="no"
+tsan="no"
fortify_source=""
strip_opt="yes"
tcg_interpreter="no"
@@ -1150,6 +1151,10 @@ for opt do
;;
--disable-sanitizers) sanitizers="no"
;;
+ --enable-tsan) tsan="yes"
+ ;;
+ --disable-tsan) tsan="no"
+ ;;
--enable-sparse) sparse="yes"
;;
--disable-sparse) sparse="no"
@@ -1750,6 +1755,7 @@ Advanced options (experts only):
--with-pkgversion=VERS use specified string as sub-version of the package
--enable-debug enable common debug build options
--enable-sanitizers enable default sanitizers
+ --enable-tsan enable thread sanitizer
--disable-strip disable stripping binaries
--disable-werror disable compilation abort on warning
--disable-stack-protector disable compiler-provided stack protection
@@ -6192,6 +6198,30 @@ if test "$fuzzing" = "yes" ; then
fi
fi
+# Thread sanitizer is, for now, much noisier than the other sanitizers;
+# keep it separate until that is not the case.
+if test "$tsan" = "yes" && test "$sanitizers" = "yes"; then
+ error_exit "TSAN is not supported with other sanitiziers."
+fi
+have_tsan=no
+have_tsan_iface_fiber=no
+if test "$tsan" = "yes" ; then
+ write_c_skeleton
+ if compile_prog "$CPU_CFLAGS -Werror -fsanitize=thread" "" ; then
+ have_tsan=yes
+ fi
+ cat > $TMPC << EOF
+#include <sanitizer/tsan_interface.h>
+int main(void) {
+ __tsan_create_fiber(0);
+ return 0;
+}
+EOF
+ if compile_prog "$CPU_CFLAGS -Werror -fsanitize=thread" "" ; then
+ have_tsan_iface_fiber=yes
+ fi
+fi
+
##########################################
# check for libpmem
@@ -6293,6 +6323,16 @@ if test "$have_asan" = "yes"; then
"Without code annotation, the report may be inferior."
fi
fi
+if test "$have_tsan" = "yes" ; then
+ if test "$have_tsan_iface_fiber" = "yes" ; then
+ QEMU_CFLAGS="-fsanitize=thread $QEMU_CFLAGS"
+ QEMU_LDFLAGS="-fsanitize=thread $QEMU_LDFLAGS"
+ else
+ error_exit "Cannot enable TSAN due to missing fiber annotation interface."
+ fi
+elif test "$tsan" = "yes" ; then
+ error_exit "Cannot enable TSAN due to missing sanitize thread interface."
+fi
if test "$have_ubsan" = "yes"; then
QEMU_CFLAGS="-fsanitize=undefined $QEMU_CFLAGS"
QEMU_LDFLAGS="-fsanitize=undefined $QEMU_LDFLAGS"
@@ -6328,7 +6368,8 @@ if test "$werror" = "yes"; then
QEMU_CFLAGS="-Werror $QEMU_CFLAGS"
fi
-if test "$solaris" = "no" ; then
+# Exclude --warn-common with TSan to suppress warnings from the TSan libraries.
+if test "$solaris" = "no" && test "$tsan" = "no"; then
if $ld --version 2>/dev/null | grep "GNU ld" >/dev/null 2>/dev/null ; then
QEMU_LDFLAGS="-Wl,--warn-common $QEMU_LDFLAGS"
fi
@@ -7382,6 +7423,10 @@ if test "$have_asan_iface_fiber" = "yes" ; then
echo "CONFIG_ASAN_IFACE_FIBER=y" >> $config_host_mak
fi
+if test "$have_tsan" = "yes" && test "$have_tsan_iface_fiber" = "yes" ; then
+ echo "CONFIG_TSAN=y" >> $config_host_mak
+fi
+
if test "$has_environ" = "yes" ; then
echo "CONFIG_HAS_ENVIRON=y" >> $config_host_mak
fi
@@ -37,18 +37,33 @@
#endif
#endif
+#ifdef CONFIG_TSAN
+#include <sanitizer/tsan_interface.h>
+#endif
+
typedef struct {
Coroutine base;
void *stack;
size_t stack_size;
sigjmp_buf env;
+ void *tsan_co_fiber;
+ void *tsan_caller_fiber;
+
#ifdef CONFIG_VALGRIND_H
unsigned int valgrind_stack_id;
#endif
} CoroutineUContext;
+#define UC_DEBUG 0
+#if UC_DEBUG && defined(CONFIG_TSAN)
+#define UC_TRACE(fmt, ...) fprintf(stderr, "%s:%d:%p " fmt "\n", \
+ __func__, __LINE__, __tsan_get_current_fiber(), ##__VA_ARGS__);
+#else
+#define UC_TRACE(fmt, ...)
+#endif
+
/**
* Per-thread coroutine bookkeeping
*/
@@ -65,7 +80,20 @@ union cc_arg {
int i[2];
};
-static void finish_switch_fiber(void *fake_stack_save)
+/* QEMU_ALWAYS_INLINE only does so if __OPTIMIZE__, so we cannot use it. */
+static inline __attribute__((always_inline))
+void on_new_fiber(CoroutineUContext *co)
+{
+#ifdef CONFIG_TSAN
+ co->tsan_co_fiber = __tsan_create_fiber(0); /* flags: sync on switch */
+ co->tsan_caller_fiber = __tsan_get_current_fiber();
+ UC_TRACE("Create new TSAN co fiber. co: %p co fiber: %p caller fiber: %p ",
+ co, co->tsan_co_fiber, co->tsan_caller_fiber);
+#endif
+}
+
+static inline __attribute__((always_inline))
+void finish_switch_fiber(void *fake_stack_save)
{
#ifdef CONFIG_ASAN
const void *bottom_old;
@@ -78,18 +106,40 @@ static void finish_switch_fiber(void *fake_stack_save)
leader.stack_size = size_old;
}
#endif
+#ifdef CONFIG_TSAN
+ if (fake_stack_save) {
+ __tsan_release(fake_stack_save);
+ __tsan_switch_to_fiber(fake_stack_save, 0); /* 0=synchronize */
+ }
+#endif
}
-static void start_switch_fiber(void **fake_stack_save,
- const void *bottom, size_t size)
+static inline __attribute__((always_inline)) void start_switch_fiber(
+ CoroutineAction action, void **fake_stack_save,
+ const void *bottom, size_t size, void *new_fiber)
{
#ifdef CONFIG_ASAN
- __sanitizer_start_switch_fiber(fake_stack_save, bottom, size);
+ if (action == COROUTINE_TERMINATE) {
+ __sanitizer_start_switch_fiber(
+ action == COROUTINE_TERMINATE ? NULL : fake_stack_save,
+ bottom, size);
+ }
+#endif
+#ifdef CONFIG_TSAN
+ void *curr_fiber =
+ __tsan_get_current_fiber();
+ __tsan_acquire(curr_fiber);
+
+ UC_TRACE("Current fiber: %p.", curr_fiber);
+ *fake_stack_save = curr_fiber;
+ UC_TRACE("Switch to fiber %p", new_fiber);
+ __tsan_switch_to_fiber(new_fiber, 0); /* 0=synchronize */
#endif
}
static void coroutine_trampoline(int i0, int i1)
{
+ UC_TRACE("Start trampoline");
union cc_arg arg;
CoroutineUContext *self;
Coroutine *co;
@@ -104,21 +154,34 @@ static void coroutine_trampoline(int i0, int i1)
/* Initialize longjmp environment and switch back the caller */
if (!sigsetjmp(self->env, 0)) {
- start_switch_fiber(&fake_stack_save,
- leader.stack, leader.stack_size);
+ UC_TRACE("Current fiber: %p. Set co %p to env 0x%lx",
+ __tsan_get_current_fiber(), self, (unsigned long)self->env);
+ start_switch_fiber(
+ COROUTINE_YIELD,
+ &fake_stack_save,
+ leader.stack,
+ leader.stack_size,
+ self->tsan_caller_fiber);
+ UC_TRACE("Jump to co %p caller fiber %p env 0x%lx",
+ co, self->tsan_caller_fiber, *(unsigned long *)co->entry_arg);
siglongjmp(*(sigjmp_buf *)co->entry_arg, 1);
}
+ UC_TRACE("After first siglongjmp");
+
finish_switch_fiber(fake_stack_save);
while (true) {
co->entry(co->entry_arg);
+ UC_TRACE("switch from co %p to caller co %p fiber %p\n",
+ co, co->caller, self->tsan_caller_fiber);
qemu_coroutine_switch(co, co->caller, COROUTINE_TERMINATE);
}
}
Coroutine *qemu_coroutine_new(void)
{
+ UC_TRACE("Start new coroutine");
CoroutineUContext *co;
ucontext_t old_uc, uc;
sigjmp_buf old_env;
@@ -154,12 +217,16 @@ Coroutine *qemu_coroutine_new(void)
arg.p = co;
+ on_new_fiber(co);
makecontext(&uc, (void (*)(void))coroutine_trampoline,
2, arg.i[0], arg.i[1]);
/* swapcontext() in, siglongjmp() back out */
if (!sigsetjmp(old_env, 0)) {
- start_switch_fiber(&fake_stack_save, co->stack, co->stack_size);
+ start_switch_fiber(
+ COROUTINE_YIELD,
+ &fake_stack_save,
+ co->stack, co->stack_size, co->tsan_co_fiber);
swapcontext(&old_uc, &uc);
}
@@ -185,6 +252,7 @@ static inline void valgrind_stack_deregister(CoroutineUContext *co)
void qemu_coroutine_delete(Coroutine *co_)
{
+ UC_TRACE("Nuking co %p from orbit", co_);
CoroutineUContext *co = DO_UPCAST(CoroutineUContext, base, co_);
#ifdef CONFIG_VALGRIND_H
@@ -209,6 +277,10 @@ qemu_coroutine_switch(Coroutine *from_, Coroutine *to_,
{
CoroutineUContext *from = DO_UPCAST(CoroutineUContext, base, from_);
CoroutineUContext *to = DO_UPCAST(CoroutineUContext, base, to_);
+ UC_TRACE("from to: %p %p uc: %p %p. fibers: %p %p caller fibers: %p %p\n",
+ from_, to_, from, to,
+ from->tsan_co_fiber, to->tsan_co_fiber,
+ from->tsan_caller_fiber, to->tsan_caller_fiber);
int ret;
void *fake_stack_save = NULL;
@@ -216,8 +288,8 @@ qemu_coroutine_switch(Coroutine *from_, Coroutine *to_,
ret = sigsetjmp(from->env, 0);
if (ret == 0) {
- start_switch_fiber(action == COROUTINE_TERMINATE ?
- NULL : &fake_stack_save, to->stack, to->stack_size);
+ start_switch_fiber(action, &fake_stack_save,
+ to->stack, to->stack_size, to->tsan_co_fiber);
siglongjmp(to->env, action);
}
@@ -231,6 +303,13 @@ Coroutine *qemu_coroutine_self(void)
if (!current) {
current = &leader.base;
}
+#ifdef CONFIG_TSAN
+ if (!leader.tsan_co_fiber) {
+ leader.tsan_co_fiber = __tsan_get_current_fiber();
+ UC_TRACE("For co %p set leader co fiber to %p",
+ current, leader.tsan_co_fiber);
+ }
+#endif
return current;
}