qemu-e2k/qemu-io.c
Lluís Vilanova 5b808275f3 trace: Multi-backend tracing
Adds support to compile QEMU with multiple tracing backends at the same time.

For example, you can compile QEMU with:

  $ ./configure --enable-trace-backends=ftrace,dtrace

Where 'ftrace' can be handy for having an in-flight record of events, and 'dtrace' can be later used to extract more information from the system.

This patch allows having both available without recompiling QEMU.

Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-06-09 15:43:40 +02:00

495 lines
12 KiB
C

/*
* Command line utility to exercise the QEMU I/O path.
*
* Copyright (C) 2009 Red Hat, Inc.
* Copyright (c) 2003-2005 Silicon Graphics, Inc.
*
* 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 <sys/time.h>
#include <sys/types.h>
#include <stdarg.h>
#include <stdio.h>
#include <getopt.h>
#include <libgen.h>
#include "qemu-io.h"
#include "qemu/main-loop.h"
#include "qemu/option.h"
#include "qemu/config-file.h"
#include "qemu/readline.h"
#include "block/block_int.h"
#include "trace/control.h"
#define CMD_NOFILE_OK 0x01
static char *progname;
static BlockDriverState *qemuio_bs;
/* qemu-io commands passed using -c */
static int ncmdline;
static char **cmdline;
static ReadLineState *readline_state;
static int close_f(BlockDriverState *bs, int argc, char **argv)
{
bdrv_unref(bs);
qemuio_bs = NULL;
return 0;
}
static const cmdinfo_t close_cmd = {
.name = "close",
.altname = "c",
.cfunc = close_f,
.oneline = "close the current open file",
};
static int openfile(char *name, int flags, int growable, QDict *opts)
{
Error *local_err = NULL;
if (qemuio_bs) {
fprintf(stderr, "file open already, try 'help close'\n");
QDECREF(opts);
return 1;
}
if (growable) {
if (bdrv_open(&qemuio_bs, name, NULL, opts, flags | BDRV_O_PROTOCOL,
NULL, &local_err))
{
fprintf(stderr, "%s: can't open%s%s: %s\n", progname,
name ? " device " : "", name ?: "",
error_get_pretty(local_err));
error_free(local_err);
return 1;
}
} else {
qemuio_bs = bdrv_new("hda", &error_abort);
if (bdrv_open(&qemuio_bs, name, NULL, opts, flags, NULL, &local_err)
< 0)
{
fprintf(stderr, "%s: can't open%s%s: %s\n", progname,
name ? " device " : "", name ?: "",
error_get_pretty(local_err));
error_free(local_err);
bdrv_unref(qemuio_bs);
qemuio_bs = NULL;
return 1;
}
}
return 0;
}
static void open_help(void)
{
printf(
"\n"
" opens a new file in the requested mode\n"
"\n"
" Example:\n"
" 'open -Cn /tmp/data' - creates/opens data file read-write and uncached\n"
"\n"
" Opens a file for subsequent use by all of the other qemu-io commands.\n"
" -r, -- open file read-only\n"
" -s, -- use snapshot file\n"
" -n, -- disable host cache\n"
" -g, -- allow file to grow (only applies to protocols)\n"
" -o, -- options to be given to the block driver"
"\n");
}
static int open_f(BlockDriverState *bs, int argc, char **argv);
static const cmdinfo_t open_cmd = {
.name = "open",
.altname = "o",
.cfunc = open_f,
.argmin = 1,
.argmax = -1,
.flags = CMD_NOFILE_OK,
.args = "[-Crsn] [-o options] [path]",
.oneline = "open the file specified by path",
.help = open_help,
};
static QemuOptsList empty_opts = {
.name = "drive",
.merge_lists = true,
.head = QTAILQ_HEAD_INITIALIZER(empty_opts.head),
.desc = {
/* no elements => accept any params */
{ /* end of list */ }
},
};
static int open_f(BlockDriverState *bs, int argc, char **argv)
{
int flags = 0;
int readonly = 0;
int growable = 0;
int c;
QemuOpts *qopts;
QDict *opts;
while ((c = getopt(argc, argv, "snrgo:")) != EOF) {
switch (c) {
case 's':
flags |= BDRV_O_SNAPSHOT;
break;
case 'n':
flags |= BDRV_O_NOCACHE | BDRV_O_CACHE_WB;
break;
case 'r':
readonly = 1;
break;
case 'g':
growable = 1;
break;
case 'o':
if (!qemu_opts_parse(&empty_opts, optarg, 0)) {
printf("could not parse option list -- %s\n", optarg);
qemu_opts_reset(&empty_opts);
return 0;
}
break;
default:
qemu_opts_reset(&empty_opts);
return qemuio_command_usage(&open_cmd);
}
}
if (!readonly) {
flags |= BDRV_O_RDWR;
}
qopts = qemu_opts_find(&empty_opts, NULL);
opts = qopts ? qemu_opts_to_qdict(qopts, NULL) : NULL;
qemu_opts_reset(&empty_opts);
if (optind == argc - 1) {
return openfile(argv[optind], flags, growable, opts);
} else if (optind == argc) {
return openfile(NULL, flags, growable, opts);
} else {
QDECREF(opts);
return qemuio_command_usage(&open_cmd);
}
}
static int quit_f(BlockDriverState *bs, int argc, char **argv)
{
return 1;
}
static const cmdinfo_t quit_cmd = {
.name = "quit",
.altname = "q",
.cfunc = quit_f,
.argmin = -1,
.argmax = -1,
.flags = CMD_FLAG_GLOBAL,
.oneline = "exit the program",
};
static void usage(const char *name)
{
printf(
"Usage: %s [-h] [-V] [-rsnm] [-c STRING] ... [file]\n"
"QEMU Disk exerciser\n"
"\n"
" -c, --cmd STRING execute command with its arguments\n"
" from the given string\n"
" -r, --read-only export read-only\n"
" -s, --snapshot use snapshot file\n"
" -n, --nocache disable host cache\n"
" -g, --growable allow file to grow (only applies to protocols)\n"
" -m, --misalign misalign allocations for O_DIRECT\n"
" -k, --native-aio use kernel AIO implementation (on Linux only)\n"
" -t, --cache=MODE use the given cache mode for the image\n"
" -T, --trace FILE enable trace events listed in the given file\n"
" -h, --help display this help and exit\n"
" -V, --version output version information and exit\n"
"\n"
"See '%s -c help' for information on available commands."
"\n",
name, name);
}
static char *get_prompt(void)
{
static char prompt[FILENAME_MAX + 2 /*"> "*/ + 1 /*"\0"*/ ];
if (!prompt[0]) {
snprintf(prompt, sizeof(prompt), "%s> ", progname);
}
return prompt;
}
static void GCC_FMT_ATTR(2, 3) readline_printf_func(void *opaque,
const char *fmt, ...)
{
va_list ap;
va_start(ap, fmt);
vprintf(fmt, ap);
va_end(ap);
}
static void readline_flush_func(void *opaque)
{
fflush(stdout);
}
static void readline_func(void *opaque, const char *str, void *readline_opaque)
{
char **line = readline_opaque;
*line = g_strdup(str);
}
static void completion_match(const char *cmd, void *opaque)
{
readline_add_completion(readline_state, cmd);
}
static void readline_completion_func(void *opaque, const char *str)
{
readline_set_completion_index(readline_state, strlen(str));
qemuio_complete_command(str, completion_match, NULL);
}
static char *fetchline_readline(void)
{
char *line = NULL;
readline_start(readline_state, get_prompt(), 0, readline_func, &line);
while (!line) {
int ch = getchar();
if (ch == EOF) {
break;
}
readline_handle_byte(readline_state, ch);
}
return line;
}
#define MAXREADLINESZ 1024
static char *fetchline_fgets(void)
{
char *p, *line = g_malloc(MAXREADLINESZ);
if (!fgets(line, MAXREADLINESZ, stdin)) {
g_free(line);
return NULL;
}
p = line + strlen(line);
if (p != line && p[-1] == '\n') {
p[-1] = '\0';
}
return line;
}
static char *fetchline(void)
{
if (readline_state) {
return fetchline_readline();
} else {
return fetchline_fgets();
}
}
static void prep_fetchline(void *opaque)
{
int *fetchable = opaque;
qemu_set_fd_handler(STDIN_FILENO, NULL, NULL, NULL);
*fetchable= 1;
}
static void command_loop(void)
{
int i, done = 0, fetchable = 0, prompted = 0;
char *input;
for (i = 0; !done && i < ncmdline; i++) {
done = qemuio_command(qemuio_bs, cmdline[i]);
}
if (cmdline) {
g_free(cmdline);
return;
}
while (!done) {
if (!prompted) {
printf("%s", get_prompt());
fflush(stdout);
qemu_set_fd_handler(STDIN_FILENO, prep_fetchline, NULL, &fetchable);
prompted = 1;
}
main_loop_wait(false);
if (!fetchable) {
continue;
}
input = fetchline();
if (input == NULL) {
break;
}
done = qemuio_command(qemuio_bs, input);
g_free(input);
prompted = 0;
fetchable = 0;
}
qemu_set_fd_handler(STDIN_FILENO, NULL, NULL, NULL);
}
static void add_user_command(char *optarg)
{
cmdline = g_realloc(cmdline, ++ncmdline * sizeof(char *));
cmdline[ncmdline-1] = optarg;
}
static void reenable_tty_echo(void)
{
qemu_set_tty_echo(STDIN_FILENO, true);
}
int main(int argc, char **argv)
{
int readonly = 0;
int growable = 0;
const char *sopt = "hVc:d:rsnmgkt:T:";
const struct option lopt[] = {
{ "help", 0, NULL, 'h' },
{ "version", 0, NULL, 'V' },
{ "offset", 1, NULL, 'o' },
{ "cmd", 1, NULL, 'c' },
{ "read-only", 0, NULL, 'r' },
{ "snapshot", 0, NULL, 's' },
{ "nocache", 0, NULL, 'n' },
{ "misalign", 0, NULL, 'm' },
{ "growable", 0, NULL, 'g' },
{ "native-aio", 0, NULL, 'k' },
{ "discard", 1, NULL, 'd' },
{ "cache", 1, NULL, 't' },
{ "trace", 1, NULL, 'T' },
{ NULL, 0, NULL, 0 }
};
int c;
int opt_index = 0;
int flags = BDRV_O_UNMAP;
#ifdef CONFIG_POSIX
signal(SIGPIPE, SIG_IGN);
#endif
progname = basename(argv[0]);
qemu_init_exec_dir(argv[0]);
while ((c = getopt_long(argc, argv, sopt, lopt, &opt_index)) != -1) {
switch (c) {
case 's':
flags |= BDRV_O_SNAPSHOT;
break;
case 'n':
flags |= BDRV_O_NOCACHE | BDRV_O_CACHE_WB;
break;
case 'd':
if (bdrv_parse_discard_flags(optarg, &flags) < 0) {
error_report("Invalid discard option: %s", optarg);
exit(1);
}
break;
case 'c':
add_user_command(optarg);
break;
case 'r':
readonly = 1;
break;
case 'm':
qemuio_misalign = true;
break;
case 'g':
growable = 1;
break;
case 'k':
flags |= BDRV_O_NATIVE_AIO;
break;
case 't':
if (bdrv_parse_cache_flags(optarg, &flags) < 0) {
error_report("Invalid cache option: %s", optarg);
exit(1);
}
break;
case 'T':
if (!trace_init_backends(optarg, NULL)) {
exit(1); /* error message will have been printed */
}
break;
case 'V':
printf("%s version %s\n", progname, QEMU_VERSION);
exit(0);
case 'h':
usage(progname);
exit(0);
default:
usage(progname);
exit(1);
}
}
if ((argc - optind) > 1) {
usage(progname);
exit(1);
}
qemu_init_main_loop();
bdrv_init();
/* initialize commands */
qemuio_add_command(&quit_cmd);
qemuio_add_command(&open_cmd);
qemuio_add_command(&close_cmd);
if (isatty(STDIN_FILENO)) {
readline_state = readline_init(readline_printf_func,
readline_flush_func,
NULL,
readline_completion_func);
qemu_set_tty_echo(STDIN_FILENO, false);
atexit(reenable_tty_echo);
}
/* open the device */
if (!readonly) {
flags |= BDRV_O_RDWR;
}
if ((argc - optind) == 1) {
openfile(argv[optind], flags, growable, NULL);
}
command_loop();
/*
* Make sure all outstanding requests complete before the program exits.
*/
bdrv_drain_all();
if (qemuio_bs) {
bdrv_unref(qemuio_bs);
}
g_free(readline_state);
return 0;
}