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authorLluís <xscript@gmx.net>2011-08-31 20:30:57 +0200
committerStefan Hajnoczi <stefanha@linux.vnet.ibm.com>2011-09-01 10:34:53 +0100
commitedb47ec498a5c00607e8d428668d5141822a9eac (patch)
tree3e1e9edc6ddfae6e34c132f16ec04fe32eb5335d /simpletrace.c
parent09001ee7b27b9b5f049362efc427d03e2186a431 (diff)
downloadhqemu-edb47ec498a5c00607e8d428668d5141822a9eac.zip
hqemu-edb47ec498a5c00607e8d428668d5141822a9eac.tar.gz
trace: move backend-specific code into the trace/ directory
Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
Diffstat (limited to 'simpletrace.c')
-rw-r--r--simpletrace.c355
1 files changed, 0 insertions, 355 deletions
diff --git a/simpletrace.c b/simpletrace.c
deleted file mode 100644
index de355e9..0000000
--- a/simpletrace.c
+++ /dev/null
@@ -1,355 +0,0 @@
-/*
- * Simple trace backend
- *
- * Copyright IBM, Corp. 2010
- *
- * This work is licensed under the terms of the GNU GPL, version 2. See
- * the COPYING file in the top-level directory.
- *
- */
-
-#include <stdlib.h>
-#include <stdint.h>
-#include <stdio.h>
-#include <time.h>
-#include <signal.h>
-#include <pthread.h>
-#include "qemu-timer.h"
-#include "trace.h"
-
-/** Trace file header event ID */
-#define HEADER_EVENT_ID (~(uint64_t)0) /* avoids conflicting with TraceEventIDs */
-
-/** Trace file magic number */
-#define HEADER_MAGIC 0xf2b177cb0aa429b4ULL
-
-/** Trace file version number, bump if format changes */
-#define HEADER_VERSION 0
-
-/** Records were dropped event ID */
-#define DROPPED_EVENT_ID (~(uint64_t)0 - 1)
-
-/** Trace record is valid */
-#define TRACE_RECORD_VALID ((uint64_t)1 << 63)
-
-/** Trace buffer entry */
-typedef struct {
- uint64_t event;
- uint64_t timestamp_ns;
- uint64_t x1;
- uint64_t x2;
- uint64_t x3;
- uint64_t x4;
- uint64_t x5;
- uint64_t x6;
-} TraceRecord;
-
-enum {
- TRACE_BUF_LEN = 4096,
- TRACE_BUF_FLUSH_THRESHOLD = TRACE_BUF_LEN / 4,
-};
-
-/*
- * Trace records are written out by a dedicated thread. The thread waits for
- * records to become available, writes them out, and then waits again.
- */
-static pthread_mutex_t trace_lock = PTHREAD_MUTEX_INITIALIZER;
-static pthread_cond_t trace_available_cond = PTHREAD_COND_INITIALIZER;
-static pthread_cond_t trace_empty_cond = PTHREAD_COND_INITIALIZER;
-static bool trace_available;
-static bool trace_writeout_enabled;
-
-static TraceRecord trace_buf[TRACE_BUF_LEN];
-static unsigned int trace_idx;
-static FILE *trace_fp;
-static char *trace_file_name = NULL;
-
-/**
- * Read a trace record from the trace buffer
- *
- * @idx Trace buffer index
- * @record Trace record to fill
- *
- * Returns false if the record is not valid.
- */
-static bool get_trace_record(unsigned int idx, TraceRecord *record)
-{
- if (!(trace_buf[idx].event & TRACE_RECORD_VALID)) {
- return false;
- }
-
- __sync_synchronize(); /* read memory barrier before accessing record */
-
- *record = trace_buf[idx];
- record->event &= ~TRACE_RECORD_VALID;
- return true;
-}
-
-/**
- * Kick writeout thread
- *
- * @wait Whether to wait for writeout thread to complete
- */
-static void flush_trace_file(bool wait)
-{
- pthread_mutex_lock(&trace_lock);
- trace_available = true;
- pthread_cond_signal(&trace_available_cond);
-
- if (wait) {
- pthread_cond_wait(&trace_empty_cond, &trace_lock);
- }
-
- pthread_mutex_unlock(&trace_lock);
-}
-
-static void wait_for_trace_records_available(void)
-{
- pthread_mutex_lock(&trace_lock);
- while (!(trace_available && trace_writeout_enabled)) {
- pthread_cond_signal(&trace_empty_cond);
- pthread_cond_wait(&trace_available_cond, &trace_lock);
- }
- trace_available = false;
- pthread_mutex_unlock(&trace_lock);
-}
-
-static void *writeout_thread(void *opaque)
-{
- TraceRecord record;
- unsigned int writeout_idx = 0;
- unsigned int num_available, idx;
- size_t unused __attribute__ ((unused));
-
- for (;;) {
- wait_for_trace_records_available();
-
- num_available = trace_idx - writeout_idx;
- if (num_available > TRACE_BUF_LEN) {
- record = (TraceRecord){
- .event = DROPPED_EVENT_ID,
- .x1 = num_available,
- };
- unused = fwrite(&record, sizeof(record), 1, trace_fp);
- writeout_idx += num_available;
- }
-
- idx = writeout_idx % TRACE_BUF_LEN;
- while (get_trace_record(idx, &record)) {
- trace_buf[idx].event = 0; /* clear valid bit */
- unused = fwrite(&record, sizeof(record), 1, trace_fp);
- idx = ++writeout_idx % TRACE_BUF_LEN;
- }
-
- fflush(trace_fp);
- }
- return NULL;
-}
-
-static void trace(TraceEventID event, uint64_t x1, uint64_t x2, uint64_t x3,
- uint64_t x4, uint64_t x5, uint64_t x6)
-{
- unsigned int idx;
- uint64_t timestamp;
-
- if (!trace_list[event].state) {
- return;
- }
-
- timestamp = get_clock();
-
- idx = __sync_fetch_and_add(&trace_idx, 1) % TRACE_BUF_LEN;
- trace_buf[idx] = (TraceRecord){
- .event = event,
- .timestamp_ns = timestamp,
- .x1 = x1,
- .x2 = x2,
- .x3 = x3,
- .x4 = x4,
- .x5 = x5,
- .x6 = x6,
- };
- __sync_synchronize(); /* write barrier before marking as valid */
- trace_buf[idx].event |= TRACE_RECORD_VALID;
-
- if ((idx + 1) % TRACE_BUF_FLUSH_THRESHOLD == 0) {
- flush_trace_file(false);
- }
-}
-
-void trace0(TraceEventID event)
-{
- trace(event, 0, 0, 0, 0, 0, 0);
-}
-
-void trace1(TraceEventID event, uint64_t x1)
-{
- trace(event, x1, 0, 0, 0, 0, 0);
-}
-
-void trace2(TraceEventID event, uint64_t x1, uint64_t x2)
-{
- trace(event, x1, x2, 0, 0, 0, 0);
-}
-
-void trace3(TraceEventID event, uint64_t x1, uint64_t x2, uint64_t x3)
-{
- trace(event, x1, x2, x3, 0, 0, 0);
-}
-
-void trace4(TraceEventID event, uint64_t x1, uint64_t x2, uint64_t x3, uint64_t x4)
-{
- trace(event, x1, x2, x3, x4, 0, 0);
-}
-
-void trace5(TraceEventID event, uint64_t x1, uint64_t x2, uint64_t x3, uint64_t x4, uint64_t x5)
-{
- trace(event, x1, x2, x3, x4, x5, 0);
-}
-
-void trace6(TraceEventID event, uint64_t x1, uint64_t x2, uint64_t x3, uint64_t x4, uint64_t x5, uint64_t x6)
-{
- trace(event, x1, x2, x3, x4, x5, x6);
-}
-
-void st_set_trace_file_enabled(bool enable)
-{
- if (enable == !!trace_fp) {
- return; /* no change */
- }
-
- /* Halt trace writeout */
- flush_trace_file(true);
- trace_writeout_enabled = false;
- flush_trace_file(true);
-
- if (enable) {
- static const TraceRecord header = {
- .event = HEADER_EVENT_ID,
- .timestamp_ns = HEADER_MAGIC,
- .x1 = HEADER_VERSION,
- };
-
- trace_fp = fopen(trace_file_name, "w");
- if (!trace_fp) {
- return;
- }
-
- if (fwrite(&header, sizeof header, 1, trace_fp) != 1) {
- fclose(trace_fp);
- trace_fp = NULL;
- return;
- }
-
- /* Resume trace writeout */
- trace_writeout_enabled = true;
- flush_trace_file(false);
- } else {
- fclose(trace_fp);
- trace_fp = NULL;
- }
-}
-
-/**
- * Set the name of a trace file
- *
- * @file The trace file name or NULL for the default name-<pid> set at
- * config time
- */
-bool st_set_trace_file(const char *file)
-{
- st_set_trace_file_enabled(false);
-
- free(trace_file_name);
-
- if (!file) {
- if (asprintf(&trace_file_name, CONFIG_TRACE_FILE, getpid()) < 0) {
- trace_file_name = NULL;
- return false;
- }
- } else {
- if (asprintf(&trace_file_name, "%s", file) < 0) {
- trace_file_name = NULL;
- return false;
- }
- }
-
- st_set_trace_file_enabled(true);
- return true;
-}
-
-void st_print_trace_file_status(FILE *stream, int (*stream_printf)(FILE *stream, const char *fmt, ...))
-{
- stream_printf(stream, "Trace file \"%s\" %s.\n",
- trace_file_name, trace_fp ? "on" : "off");
-}
-
-void st_print_trace(FILE *stream, int (*stream_printf)(FILE *stream, const char *fmt, ...))
-{
- unsigned int i;
-
- for (i = 0; i < TRACE_BUF_LEN; i++) {
- TraceRecord record;
-
- if (!get_trace_record(i, &record)) {
- continue;
- }
- stream_printf(stream, "Event %" PRIu64 " : %" PRIx64 " %" PRIx64
- " %" PRIx64 " %" PRIx64 " %" PRIx64 " %" PRIx64 "\n",
- record.event, record.x1, record.x2,
- record.x3, record.x4, record.x5,
- record.x6);
- }
-}
-
-void st_print_trace_events(FILE *stream, int (*stream_printf)(FILE *stream, const char *fmt, ...))
-{
- unsigned int i;
-
- for (i = 0; i < NR_TRACE_EVENTS; i++) {
- stream_printf(stream, "%s [Event ID %u] : state %u\n",
- trace_list[i].tp_name, i, trace_list[i].state);
- }
-}
-
-bool st_change_trace_event_state(const char *name, bool enabled)
-{
- unsigned int i;
-
- for (i = 0; i < NR_TRACE_EVENTS; i++) {
- if (!strcmp(trace_list[i].tp_name, name)) {
- trace_list[i].state = enabled;
- return true;
- }
- }
- return false;
-}
-
-void st_flush_trace_buffer(void)
-{
- flush_trace_file(true);
-}
-
-bool st_init(const char *file)
-{
- pthread_t thread;
- pthread_attr_t attr;
- sigset_t set, oldset;
- int ret;
-
- pthread_attr_init(&attr);
- pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
-
- sigfillset(&set);
- pthread_sigmask(SIG_SETMASK, &set, &oldset);
- ret = pthread_create(&thread, &attr, writeout_thread, NULL);
- pthread_sigmask(SIG_SETMASK, &oldset, NULL);
-
- if (ret != 0) {
- return false;
- }
-
- atexit(st_flush_trace_buffer);
- st_set_trace_file(file);
- return true;
-}
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