On 22/01/2015 09:52, Pavel Dovgalyuk wrote:
> This patch adds calls to replay functions into the icount setup block.
> In record mode number of executed instructions is written to the log.
> In replay mode number of istructions to execute is taken from the replay log.
>
> Signed-off-by: Pavel Dovgalyuk <pavel.dovga...@ispras.ru>
> ---
> cpu-exec.c | 1 +
> cpus.c | 28 ++++++++++++++++++----------
> replay/replay.c | 24 ++++++++++++++++++++++++
> replay/replay.h | 4 ++++
> 4 files changed, 47 insertions(+), 10 deletions(-)
>
> diff --git a/cpu-exec.c b/cpu-exec.c
> index 49f01f5..99a0993 100644
> --- a/cpu-exec.c
> +++ b/cpu-exec.c
> @@ -531,6 +531,7 @@ int cpu_exec(CPUArchState *env)
> }
> cpu->exception_index = EXCP_INTERRUPT;
> next_tb = 0;
> + qemu_notify_event();
Why is this needed?
> cpu_loop_exit(cpu);
> }
> break;
> diff --git a/cpus.c b/cpus.c
> index c513275..8787277 100644
> --- a/cpus.c
> +++ b/cpus.c
> @@ -41,6 +41,7 @@
> #include "qemu/seqlock.h"
> #include "qapi-event.h"
> #include "hw/nmi.h"
> +#include "replay/replay.h"
>
> #ifndef _WIN32
> #include "qemu/compatfd.h"
> @@ -1342,18 +1343,22 @@ static int tcg_cpu_exec(CPUArchState *env)
> + cpu->icount_extra);
> cpu->icount_decr.u16.low = 0;
> cpu->icount_extra = 0;
> - deadline = qemu_clock_deadline_ns_all(QEMU_CLOCK_VIRTUAL);
> + if (replay_mode != REPLAY_MODE_PLAY) {
> + deadline = qemu_clock_deadline_ns_all(QEMU_CLOCK_VIRTUAL);
>
> - /* Maintain prior (possibly buggy) behaviour where if no deadline
> - * was set (as there is no QEMU_CLOCK_VIRTUAL timer) or it is more
> than
> - * INT32_MAX nanoseconds ahead, we still use INT32_MAX
> - * nanoseconds.
> - */
> - if ((deadline < 0) || (deadline > INT32_MAX)) {
> - deadline = INT32_MAX;
> - }
> + /* Maintain prior (possibly buggy) behaviour where if no deadline
> + * was set (as there is no QEMU_CLOCK_VIRTUAL timer) or it is
> more than
> + * INT32_MAX nanoseconds ahead, we still use INT32_MAX
> + * nanoseconds.
> + */
> + if ((deadline < 0) || (deadline > INT32_MAX)) {
> + deadline = INT32_MAX;
> + }
>
> - count = qemu_icount_round(deadline);
> + count = qemu_icount_round(deadline);
> + } else {
> + count = replay_get_instructions();
> + }
Please extract the "if" to a separate function tcg_get_icount_limit().
> timers_state.qemu_icount += count;
> decr = (count > 0xffff) ? 0xffff : count;
> count -= decr;
> @@ -1371,6 +1376,9 @@ static int tcg_cpu_exec(CPUArchState *env)
> + cpu->icount_extra);
> cpu->icount_decr.u32 = 0;
> cpu->icount_extra = 0;
> + if (replay_mode == REPLAY_MODE_PLAY) {
> + replay_exec_instructions();
replay_account_executed_instructions()
> + }
> }
> return ret;
> }
> diff --git a/replay/replay.c b/replay/replay.c
> index a43bbbc..d6f5c4b 100755
> --- a/replay/replay.c
> +++ b/replay/replay.c
> @@ -58,3 +58,27 @@ uint64_t replay_get_current_step(void)
> {
> return cpu_get_icount_raw();
> }
> +
> +int replay_get_instructions(void)
> +{
> + int res = 0;
> + replay_mutex_lock();
> + if (skip_async_events(EVENT_INSTRUCTION)) {
> + res = replay_state.instructions_count;
> + }
> + replay_mutex_unlock();
> + return res;
> +}
> +
> +void replay_exec_instructions(void)
> +{
> + if (replay_state.instructions_count > 0) {
> + int count = (int)(replay_get_current_step()
> + - replay_state.current_step);
> + replay_state.instructions_count -= count;
> + replay_state.current_step += count;
> + if (replay_state.instructions_count == 0 && count != 0) {
If replay_state.instructions_count is now zero, count must be nonzero
(because replay_state.instructions_count was > 0) before.
> + replay_has_unread_data = 0;
> + }
Can replay_state.instructions_count be < count at all? If not, and if
replay_state.instructions_count is zero, then count must also be zero.
If so, I suggest rewriting as
int count = (int)(replay_get_current_step()
- replay_state.current_step);
assert(replay_state.instructions_count >= count);
replay_state.instructions_count -= count;
replay_state.current_step += count;
if (replay_state.instructions_count == 0) {
replay_has_unread_data = 0;
}
Paolo
> + }
> +}
> diff --git a/replay/replay.h b/replay/replay.h
> index a03c748..e425dea 100755
> --- a/replay/replay.h
> +++ b/replay/replay.h
> @@ -22,5 +22,9 @@ extern ReplayMode replay_mode;
>
> /*! Returns number of executed instructions. */
> uint64_t replay_get_current_step(void);
> +/*! Returns number of instructions to execute in replay mode. */
> +int replay_get_instructions(void);
> +/*! Updates instructions counter in replay mode. */
> +void replay_exec_instructions(void);
>
> #endif
>
