--- /dev/null
+/*
+ * replay.c
+ *
+ * Copyright (c) 2010-2015 Institute for System Programming
+ * of the Russian Academy of Sciences.
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ *
+ */
+
+#include "qemu/osdep.h"
+#include "qapi/error.h"
+#include "qemu-common.h"
+#include "sysemu/replay.h"
+#include "replay-internal.h"
+#include "qemu/timer.h"
+#include "qemu/main-loop.h"
+#include "sysemu/sysemu.h"
+#include "qemu/error-report.h"
+
+/* Current version of the replay mechanism.
+ Increase it when file format changes. */
+#define REPLAY_VERSION 0xe02004
+/* Size of replay log header */
+#define HEADER_SIZE (sizeof(uint32_t) + sizeof(uint64_t))
+
+ReplayMode replay_mode = REPLAY_MODE_NONE;
+
+/* Name of replay file */
+static char *replay_filename;
+ReplayState replay_state;
+static GSList *replay_blockers;
+
+bool replay_next_event_is(int event)
+{
+ bool res = false;
+
+ /* nothing to skip - not all instructions used */
+ if (replay_state.instructions_count != 0) {
+ assert(replay_data_kind == EVENT_INSTRUCTION);
+ return event == EVENT_INSTRUCTION;
+ }
+
+ while (true) {
+ if (event == replay_data_kind) {
+ res = true;
+ }
+ switch (replay_data_kind) {
+ case EVENT_SHUTDOWN:
+ replay_finish_event();
+ qemu_system_shutdown_request();
+ break;
+ default:
+ /* clock, time_t, checkpoint and other events */
+ return res;
+ }
+ }
+ return res;
+}
+
+uint64_t replay_get_current_step(void)
+{
+ return cpu_get_icount_raw();
+}
+
+int replay_get_instructions(void)
+{
+ int res = 0;
+ replay_mutex_lock();
+ if (replay_next_event_is(EVENT_INSTRUCTION)) {
+ res = replay_state.instructions_count;
+ }
+ replay_mutex_unlock();
+ return res;
+}
+
+void replay_account_executed_instructions(void)
+{
+ if (replay_mode == REPLAY_MODE_PLAY) {
+ replay_mutex_lock();
+ 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) {
+ assert(replay_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();
+ }
+ }
+ replay_mutex_unlock();
+ }
+}
+
+bool replay_exception(void)
+{
+ if (replay_mode == REPLAY_MODE_RECORD) {
+ replay_save_instructions();
+ replay_mutex_lock();
+ replay_put_event(EVENT_EXCEPTION);
+ replay_mutex_unlock();
+ return true;
+ } else if (replay_mode == REPLAY_MODE_PLAY) {
+ bool res = replay_has_exception();
+ if (res) {
+ replay_mutex_lock();
+ replay_finish_event();
+ replay_mutex_unlock();
+ }
+ return res;
+ }
+
+ return true;
+}
+
+bool replay_has_exception(void)
+{
+ bool res = false;
+ if (replay_mode == REPLAY_MODE_PLAY) {
+ replay_account_executed_instructions();
+ replay_mutex_lock();
+ res = replay_next_event_is(EVENT_EXCEPTION);
+ replay_mutex_unlock();
+ }
+
+ return res;
+}
+
+bool replay_interrupt(void)
+{
+ if (replay_mode == REPLAY_MODE_RECORD) {
+ replay_save_instructions();
+ replay_mutex_lock();
+ replay_put_event(EVENT_INTERRUPT);
+ replay_mutex_unlock();
+ return true;
+ } else if (replay_mode == REPLAY_MODE_PLAY) {
+ bool res = replay_has_interrupt();
+ if (res) {
+ replay_mutex_lock();
+ replay_finish_event();
+ replay_mutex_unlock();
+ }
+ return res;
+ }
+
+ return true;
+}
+
+bool replay_has_interrupt(void)
+{
+ bool res = false;
+ if (replay_mode == REPLAY_MODE_PLAY) {
+ replay_account_executed_instructions();
+ replay_mutex_lock();
+ res = replay_next_event_is(EVENT_INTERRUPT);
+ replay_mutex_unlock();
+ }
+ return res;
+}
+
+void replay_shutdown_request(void)
+{
+ if (replay_mode == REPLAY_MODE_RECORD) {
+ replay_mutex_lock();
+ replay_put_event(EVENT_SHUTDOWN);
+ replay_mutex_unlock();
+ }
+}
+
+bool replay_checkpoint(ReplayCheckpoint checkpoint)
+{
+ bool res = false;
+ assert(EVENT_CHECKPOINT + checkpoint <= EVENT_CHECKPOINT_LAST);
+ replay_save_instructions();
+
+ if (!replay_file) {
+ return true;
+ }
+
+ replay_mutex_lock();
+
+ if (replay_mode == REPLAY_MODE_PLAY) {
+ if (replay_next_event_is(EVENT_CHECKPOINT + checkpoint)) {
+ replay_finish_event();
+ } else if (replay_data_kind != EVENT_ASYNC) {
+ res = false;
+ goto out;
+ }
+ replay_read_events(checkpoint);
+ /* replay_read_events may leave some unread events.
+ Return false if not all of the events associated with
+ checkpoint were processed */
+ res = replay_data_kind != EVENT_ASYNC;
+ } else if (replay_mode == REPLAY_MODE_RECORD) {
+ replay_put_event(EVENT_CHECKPOINT + checkpoint);
+ replay_save_events(checkpoint);
+ res = true;
+ }
+out:
+ replay_mutex_unlock();
+ return res;
+}
+
+static void replay_enable(const char *fname, int mode)
+{
+ const char *fmode = NULL;
+ assert(!replay_file);
+
+ switch (mode) {
+ case REPLAY_MODE_RECORD:
+ fmode = "wb";
+ break;
+ case REPLAY_MODE_PLAY:
+ fmode = "rb";
+ break;
+ default:
+ fprintf(stderr, "Replay: internal error: invalid replay mode\n");
+ exit(1);
+ }
+
+ atexit(replay_finish);
+
+ replay_mutex_init();
+
+ replay_file = fopen(fname, fmode);
+ if (replay_file == NULL) {
+ fprintf(stderr, "Replay: open %s: %s\n", fname, strerror(errno));
+ exit(1);
+ }
+
+ replay_filename = g_strdup(fname);
+
+ replay_mode = mode;
+ replay_data_kind = -1;
+ replay_state.instructions_count = 0;
+ replay_state.current_step = 0;
+
+ /* skip file header for RECORD and check it for PLAY */
+ if (replay_mode == REPLAY_MODE_RECORD) {
+ fseek(replay_file, HEADER_SIZE, SEEK_SET);
+ } else if (replay_mode == REPLAY_MODE_PLAY) {
+ unsigned int version = replay_get_dword();
+ if (version != REPLAY_VERSION) {
+ fprintf(stderr, "Replay: invalid input log file version\n");
+ exit(1);
+ }
+ /* go to the beginning */
+ fseek(replay_file, HEADER_SIZE, SEEK_SET);
+ replay_fetch_data_kind();
+ }
+
+ replay_init_events();
+}
+
+void replay_configure(QemuOpts *opts)
+{
+ const char *fname;
+ const char *rr;
+ ReplayMode mode = REPLAY_MODE_NONE;
+ Location loc;
+
+ if (!opts) {
+ return;
+ }
+
+ loc_push_none(&loc);
+ qemu_opts_loc_restore(opts);
+
+ rr = qemu_opt_get(opts, "rr");
+ if (!rr) {
+ /* Just enabling icount */
+ goto out;
+ } else if (!strcmp(rr, "record")) {
+ mode = REPLAY_MODE_RECORD;
+ } else if (!strcmp(rr, "replay")) {
+ mode = REPLAY_MODE_PLAY;
+ } else {
+ error_report("Invalid icount rr option: %s", rr);
+ exit(1);
+ }
+
+ fname = qemu_opt_get(opts, "rrfile");
+ if (!fname) {
+ error_report("File name not specified for replay");
+ exit(1);
+ }
+
+ replay_enable(fname, mode);
+
+out:
+ loc_pop(&loc);
+}
+
+void replay_start(void)
+{
+ if (replay_mode == REPLAY_MODE_NONE) {
+ return;
+ }
+
+ if (replay_blockers) {
+ error_reportf_err(replay_blockers->data, "Record/replay: ");
+ exit(1);
+ }
+ if (!use_icount) {
+ error_report("Please enable icount to use record/replay");
+ exit(1);
+ }
+
+ /* Timer for snapshotting will be set up here. */
+
+ replay_enable_events();
+}
+
+void replay_finish(void)
+{
+ if (replay_mode == REPLAY_MODE_NONE) {
+ return;
+ }
+
+ replay_save_instructions();
+
+ /* finalize the file */
+ if (replay_file) {
+ if (replay_mode == REPLAY_MODE_RECORD) {
+ /* write end event */
+ replay_put_event(EVENT_END);
+
+ /* write header */
+ fseek(replay_file, 0, SEEK_SET);
+ replay_put_dword(REPLAY_VERSION);
+ }
+
+ fclose(replay_file);
+ replay_file = NULL;
+ }
+ if (replay_filename) {
+ g_free(replay_filename);
+ replay_filename = NULL;
+ }
+
+ replay_finish_events();
+ replay_mutex_destroy();
+}
+
+void replay_add_blocker(Error *reason)
+{
+ replay_blockers = g_slist_prepend(replay_blockers, reason);
+}
Code Review / kvmfornfv.git / blobdiff