Record/replay provides REPLAY_CLOCK_LOCKED macro to access
the clock when vm_clock_seqlock is locked. This macro is
needed because replay internals operate icount. In locked case
replay use icount_get_raw_locked for icount request, which prevents
excess locking which leads to deadlock. But previously only
record code used *_locked function and replay did not.
Therefore sometimes clock access lead to deadlocks.
This patch fixes clock access for replay too and uses *_locked
icount access function.
Signed-off-by: Pavel Dovgalyuk <Pavel.Dovgalyuk@ispras.ru>
Message-Id: <
161347990483.
1313189.
8371838968343494161.stgit@pasha-ThinkPad-X280>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
int64_t replay_save_clock(ReplayClockKind kind, int64_t clock,
int64_t raw_icount);
/*! Read the specified clock from the log or return cached data */
-int64_t replay_read_clock(ReplayClockKind kind);
+int64_t replay_read_clock(ReplayClockKind kind, int64_t raw_icount);
/*! Saves or reads the clock depending on the current replay mode. */
#define REPLAY_CLOCK(clock, value) \
- (replay_mode == REPLAY_MODE_PLAY ? replay_read_clock((clock)) \
+ (replay_mode == REPLAY_MODE_PLAY \
+ ? replay_read_clock((clock), icount_get_raw()) \
: replay_mode == REPLAY_MODE_RECORD \
- ? replay_save_clock((clock), (value), icount_get_raw()) \
- : (value))
+ ? replay_save_clock((clock), (value), icount_get_raw()) \
+ : (value))
#define REPLAY_CLOCK_LOCKED(clock, value) \
- (replay_mode == REPLAY_MODE_PLAY ? replay_read_clock((clock)) \
+ (replay_mode == REPLAY_MODE_PLAY \
+ ? replay_read_clock((clock), icount_get_raw_locked()) \
: replay_mode == REPLAY_MODE_RECORD \
? replay_save_clock((clock), (value), icount_get_raw_locked()) \
- : (value))
+ : (value))
/* Processing data from random generators */
/* Time can only go forward */
assert(diff >= 0);
- if (diff > 0) {
- replay_put_event(EVENT_INSTRUCTION);
- replay_put_dword(diff);
- replay_state.current_icount += diff;
+ if (replay_mode == REPLAY_MODE_RECORD) {
+ if (diff > 0) {
+ replay_put_event(EVENT_INSTRUCTION);
+ replay_put_dword(diff);
+ replay_state.current_icount += diff;
+ }
+ } else if (replay_mode == REPLAY_MODE_PLAY) {
+ if (diff > 0) {
+ replay_state.instruction_count -= diff;
+ replay_state.current_icount += diff;
+ if (replay_state.instruction_count == 0) {
+ assert(replay_state.data_kind == EVENT_INSTRUCTION);
+ replay_finish_event();
+ /* Wake up iothread. This is required because
+ timers will not expire until clock counters
+ will be read from the log. */
+ qemu_notify_event();
+ }
+ }
+ /* Execution reached the break step */
+ if (replay_break_icount == replay_state.current_icount) {
+ /* Cannot make callback directly from the vCPU thread */
+ timer_mod_ns(replay_break_timer,
+ qemu_clock_get_ns(QEMU_CLOCK_REALTIME));
+ }
}
}
}
/*! Reads next clock event from the input. */
-int64_t replay_read_clock(ReplayClockKind kind)
+int64_t replay_read_clock(ReplayClockKind kind, int64_t raw_icount)
{
int64_t ret;
g_assert(replay_file && replay_mutex_locked());
- replay_account_executed_instructions();
+ replay_advance_current_icount(raw_icount);
if (replay_next_event_is(EVENT_CLOCK + kind)) {
replay_read_next_clock(kind);
if (replay_mode == REPLAY_MODE_PLAY) {
g_assert(replay_mutex_locked());
if (replay_state.instruction_count > 0) {
- int count = (int)(replay_get_current_icount()
- - replay_state.current_icount);
-
- /* Time can only go forward */
- assert(count >= 0);
-
- replay_state.instruction_count -= count;
- replay_state.current_icount += count;
- if (replay_state.instruction_count == 0) {
- assert(replay_state.data_kind == EVENT_INSTRUCTION);
- replay_finish_event();
- /* Wake up iothread. This is required because
- timers will not expire until clock counters
- will be read from the log. */
- qemu_notify_event();
- }
- /* Execution reached the break step */
- if (replay_break_icount == replay_state.current_icount) {
- /* Cannot make callback directly from the vCPU thread */
- timer_mod_ns(replay_break_timer,
- qemu_clock_get_ns(QEMU_CLOCK_REALTIME));
- }
+ replay_advance_current_icount(replay_get_current_icount());
}
}
}
return 0;
}
-int64_t replay_read_clock(unsigned int kind)
+int64_t replay_read_clock(unsigned int kind, int64_t raw_icount)
{
abort();
return 0;