X-Git-Url: https://gerrit.opnfv.org/gerrit/gitweb?a=blobdiff_plain;f=qemu%2Freplay%2Freplay.c;fp=qemu%2Freplay%2Freplay.c;h=167fd2942d60307db1d8aa57679bb43a95d0f755;hb=437fd90c0250dee670290f9b714253671a990160;hp=0000000000000000000000000000000000000000;hpb=5bbd6fe9b8bab2a93e548c5a53b032d1939eec05;p=kvmfornfv.git

diff --git a/qemu/replay/replay.c b/qemu/replay/replay.c
new file mode 100644
index 000000000..167fd2942
--- /dev/null
+++ b/qemu/replay/replay.c
@@ -0,0 +1,354 @@
+/*
+ * 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);
+}