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-rw-r--r--qemu/trace/simple.c386
1 files changed, 0 insertions, 386 deletions
diff --git a/qemu/trace/simple.c b/qemu/trace/simple.c
deleted file mode 100644
index 3fdcc8226..000000000
--- a/qemu/trace/simple.c
+++ /dev/null
@@ -1,386 +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 "qemu/osdep.h"
-#ifndef _WIN32
-#include <pthread.h>
-#endif
-#include "qemu/timer.h"
-#include "trace.h"
-#include "trace/control.h"
-#include "trace/simple.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 3
-
-/** 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 records are written out by a dedicated thread. The thread waits for
- * records to become available, writes them out, and then waits again.
- */
-static CompatGMutex trace_lock;
-static CompatGCond trace_available_cond;
-static CompatGCond trace_empty_cond;
-
-static bool trace_available;
-static bool trace_writeout_enabled;
-
-enum {
- TRACE_BUF_LEN = 4096 * 64,
- TRACE_BUF_FLUSH_THRESHOLD = TRACE_BUF_LEN / 4,
-};
-
-uint8_t trace_buf[TRACE_BUF_LEN];
-static volatile gint trace_idx;
-static unsigned int writeout_idx;
-static volatile gint dropped_events;
-static uint32_t trace_pid;
-static FILE *trace_fp;
-static char *trace_file_name;
-
-/* * Trace buffer entry */
-typedef struct {
- uint64_t event; /* TraceEventID */
- uint64_t timestamp_ns;
- uint32_t length; /* in bytes */
- uint32_t pid;
- uint64_t arguments[];
-} TraceRecord;
-
-typedef struct {
- uint64_t header_event_id; /* HEADER_EVENT_ID */
- uint64_t header_magic; /* HEADER_MAGIC */
- uint64_t header_version; /* HEADER_VERSION */
-} TraceLogHeader;
-
-
-static void read_from_buffer(unsigned int idx, void *dataptr, size_t size);
-static unsigned int write_to_buffer(unsigned int idx, void *dataptr, size_t size);
-
-static void clear_buffer_range(unsigned int idx, size_t len)
-{
- uint32_t num = 0;
- while (num < len) {
- if (idx >= TRACE_BUF_LEN) {
- idx = idx % TRACE_BUF_LEN;
- }
- trace_buf[idx++] = 0;
- num++;
- }
-}
-/**
- * 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 **recordptr)
-{
- uint64_t event_flag = 0;
- TraceRecord record;
- /* read the event flag to see if its a valid record */
- read_from_buffer(idx, &record, sizeof(event_flag));
-
- if (!(record.event & TRACE_RECORD_VALID)) {
- return false;
- }
-
- smp_rmb(); /* read memory barrier before accessing record */
- /* read the record header to know record length */
- read_from_buffer(idx, &record, sizeof(TraceRecord));
- *recordptr = malloc(record.length); /* dont use g_malloc, can deadlock when traced */
- /* make a copy of record to avoid being overwritten */
- read_from_buffer(idx, *recordptr, record.length);
- smp_rmb(); /* memory barrier before clearing valid flag */
- (*recordptr)->event &= ~TRACE_RECORD_VALID;
- /* clear the trace buffer range for consumed record otherwise any byte
- * with its MSB set may be considered as a valid event id when the writer
- * thread crosses this range of buffer again.
- */
- clear_buffer_range(idx, record.length);
- return true;
-}
-
-/**
- * Kick writeout thread
- *
- * @wait Whether to wait for writeout thread to complete
- */
-static void flush_trace_file(bool wait)
-{
- g_mutex_lock(&trace_lock);
- trace_available = true;
- g_cond_signal(&trace_available_cond);
-
- if (wait) {
- g_cond_wait(&trace_empty_cond, &trace_lock);
- }
-
- g_mutex_unlock(&trace_lock);
-}
-
-static void wait_for_trace_records_available(void)
-{
- g_mutex_lock(&trace_lock);
- while (!(trace_available && trace_writeout_enabled)) {
- g_cond_signal(&trace_empty_cond);
- g_cond_wait(&trace_available_cond, &trace_lock);
- }
- trace_available = false;
- g_mutex_unlock(&trace_lock);
-}
-
-static gpointer writeout_thread(gpointer opaque)
-{
- TraceRecord *recordptr;
- union {
- TraceRecord rec;
- uint8_t bytes[sizeof(TraceRecord) + sizeof(uint64_t)];
- } dropped;
- unsigned int idx = 0;
- int dropped_count;
- size_t unused __attribute__ ((unused));
-
- for (;;) {
- wait_for_trace_records_available();
-
- if (g_atomic_int_get(&dropped_events)) {
- dropped.rec.event = DROPPED_EVENT_ID,
- dropped.rec.timestamp_ns = get_clock();
- dropped.rec.length = sizeof(TraceRecord) + sizeof(uint64_t),
- dropped.rec.pid = trace_pid;
- do {
- dropped_count = g_atomic_int_get(&dropped_events);
- } while (!g_atomic_int_compare_and_exchange(&dropped_events,
- dropped_count, 0));
- dropped.rec.arguments[0] = dropped_count;
- unused = fwrite(&dropped.rec, dropped.rec.length, 1, trace_fp);
- }
-
- while (get_trace_record(idx, &recordptr)) {
- unused = fwrite(recordptr, recordptr->length, 1, trace_fp);
- writeout_idx += recordptr->length;
- free(recordptr); /* dont use g_free, can deadlock when traced */
- idx = writeout_idx % TRACE_BUF_LEN;
- }
-
- fflush(trace_fp);
- }
- return NULL;
-}
-
-void trace_record_write_u64(TraceBufferRecord *rec, uint64_t val)
-{
- rec->rec_off = write_to_buffer(rec->rec_off, &val, sizeof(uint64_t));
-}
-
-void trace_record_write_str(TraceBufferRecord *rec, const char *s, uint32_t slen)
-{
- /* Write string length first */
- rec->rec_off = write_to_buffer(rec->rec_off, &slen, sizeof(slen));
- /* Write actual string now */
- rec->rec_off = write_to_buffer(rec->rec_off, (void*)s, slen);
-}
-
-int trace_record_start(TraceBufferRecord *rec, TraceEventID event, size_t datasize)
-{
- unsigned int idx, rec_off, old_idx, new_idx;
- uint32_t rec_len = sizeof(TraceRecord) + datasize;
- uint64_t event_u64 = event;
- uint64_t timestamp_ns = get_clock();
-
- do {
- old_idx = g_atomic_int_get(&trace_idx);
- smp_rmb();
- new_idx = old_idx + rec_len;
-
- if (new_idx - writeout_idx > TRACE_BUF_LEN) {
- /* Trace Buffer Full, Event dropped ! */
- g_atomic_int_inc(&dropped_events);
- return -ENOSPC;
- }
- } while (!g_atomic_int_compare_and_exchange(&trace_idx, old_idx, new_idx));
-
- idx = old_idx % TRACE_BUF_LEN;
-
- rec_off = idx;
- rec_off = write_to_buffer(rec_off, &event_u64, sizeof(event_u64));
- rec_off = write_to_buffer(rec_off, &timestamp_ns, sizeof(timestamp_ns));
- rec_off = write_to_buffer(rec_off, &rec_len, sizeof(rec_len));
- rec_off = write_to_buffer(rec_off, &trace_pid, sizeof(trace_pid));
-
- rec->tbuf_idx = idx;
- rec->rec_off = (idx + sizeof(TraceRecord)) % TRACE_BUF_LEN;
- return 0;
-}
-
-static void read_from_buffer(unsigned int idx, void *dataptr, size_t size)
-{
- uint8_t *data_ptr = dataptr;
- uint32_t x = 0;
- while (x < size) {
- if (idx >= TRACE_BUF_LEN) {
- idx = idx % TRACE_BUF_LEN;
- }
- data_ptr[x++] = trace_buf[idx++];
- }
-}
-
-static unsigned int write_to_buffer(unsigned int idx, void *dataptr, size_t size)
-{
- uint8_t *data_ptr = dataptr;
- uint32_t x = 0;
- while (x < size) {
- if (idx >= TRACE_BUF_LEN) {
- idx = idx % TRACE_BUF_LEN;
- }
- trace_buf[idx++] = data_ptr[x++];
- }
- return idx; /* most callers wants to know where to write next */
-}
-
-void trace_record_finish(TraceBufferRecord *rec)
-{
- TraceRecord record;
- read_from_buffer(rec->tbuf_idx, &record, sizeof(TraceRecord));
- smp_wmb(); /* write barrier before marking as valid */
- record.event |= TRACE_RECORD_VALID;
- write_to_buffer(rec->tbuf_idx, &record, sizeof(TraceRecord));
-
- if (((unsigned int)g_atomic_int_get(&trace_idx) - writeout_idx)
- > TRACE_BUF_FLUSH_THRESHOLD) {
- flush_trace_file(false);
- }
-}
-
-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 TraceLogHeader header = {
- .header_event_id = HEADER_EVENT_ID,
- .header_magic = HEADER_MAGIC,
- /* Older log readers will check for version at next location */
- .header_version = HEADER_VERSION,
- };
-
- trace_fp = fopen(trace_file_name, "wb");
- 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
- */
-void st_set_trace_file(const char *file)
-{
- st_set_trace_file_enabled(false);
-
- g_free(trace_file_name);
-
- if (!file) {
- /* Type cast needed for Windows where getpid() returns an int. */
- trace_file_name = g_strdup_printf(CONFIG_TRACE_FILE, (pid_t)getpid());
- } else {
- trace_file_name = g_strdup_printf("%s", file);
- }
-
- st_set_trace_file_enabled(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_flush_trace_buffer(void)
-{
- flush_trace_file(true);
-}
-
-/* Helper function to create a thread with signals blocked. Use glib's
- * portable threads since QEMU abstractions cannot be used due to reentrancy in
- * the tracer. Also note the signal masking on POSIX hosts so that the thread
- * does not steal signals when the rest of the program wants them blocked.
- */
-static GThread *trace_thread_create(GThreadFunc fn)
-{
- GThread *thread;
-#ifndef _WIN32
- sigset_t set, oldset;
-
- sigfillset(&set);
- pthread_sigmask(SIG_SETMASK, &set, &oldset);
-#endif
-
- thread = g_thread_new("trace-thread", fn, NULL);
-
-#ifndef _WIN32
- pthread_sigmask(SIG_SETMASK, &oldset, NULL);
-#endif
-
- return thread;
-}
-
-bool st_init(void)
-{
- GThread *thread;
-
- trace_pid = getpid();
-
- thread = trace_thread_create(writeout_thread);
- if (!thread) {
- fprintf(stderr, "warning: unable to initialize simple trace backend\n");
- return false;
- }
-
- atexit(st_flush_trace_buffer);
- return true;
-}