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-rwxr-xr-xconfigure8
-rw-r--r--docs/tracing.txt16
-rw-r--r--kvm-all.c5
-rw-r--r--scripts/tracetool/backend/ftrace.py54
-rw-r--r--trace-events7
-rw-r--r--trace/Makefile.objs1
-rw-r--r--trace/ftrace.c102
-rw-r--r--trace/ftrace.h10
8 files changed, 203 insertions, 0 deletions
diff --git a/configure b/configure
index c4d85ba..e818e8b 100755
--- a/configure
+++ b/configure
@@ -4004,6 +4004,14 @@ if test "$trace_backend" = "dtrace"; then
echo "CONFIG_TRACE_SYSTEMTAP=y" >> $config_host_mak
fi
fi
+if test "$trace_backend" = "ftrace"; then
+ if test "$linux" = "yes" ; then
+ echo "CONFIG_TRACE_FTRACE=y" >> $config_host_mak
+ trace_default=no
+ else
+ feature_not_found "ftrace(trace backend)"
+ fi
+fi
echo "CONFIG_TRACE_FILE=$trace_file" >> $config_host_mak
if test "$trace_default" = "yes"; then
echo "CONFIG_TRACE_DEFAULT=y" >> $config_host_mak
diff --git a/docs/tracing.txt b/docs/tracing.txt
index cf53c17..60ff9c5 100644
--- a/docs/tracing.txt
+++ b/docs/tracing.txt
@@ -175,6 +175,22 @@ unless you have specific needs for more advanced backends.
The "simple" backend currently does not capture string arguments, it simply
records the char* pointer value instead of the string that is pointed to.
+=== Ftrace ===
+
+The "ftrace" backend writes trace data to ftrace marker. This effectively
+sends trace events to ftrace ring buffer, and you can compare qemu trace
+data and kernel(especially kvm.ko when using KVM) trace data.
+
+if you use KVM, enable kvm events in ftrace:
+
+ # echo 1 > /sys/kernel/debug/tracing/events/kvm/enable
+
+After running qemu by root user, you can get the trace:
+
+ # cat /sys/kernel/debug/tracing/trace
+
+Restriction: "ftrace" backend is restricted to Linux only.
+
==== Monitor commands ====
* trace-file on|off|flush|set <path>
diff --git a/kvm-all.c b/kvm-all.c
index f6c0f4a..3a31602 100644
--- a/kvm-all.c
+++ b/kvm-all.c
@@ -33,6 +33,7 @@
#include "exec/memory.h"
#include "exec/address-spaces.h"
#include "qemu/event_notifier.h"
+#include "trace.h"
/* This check must be after config-host.h is included */
#ifdef CONFIG_EVENTFD
@@ -1626,6 +1627,7 @@ int kvm_cpu_exec(CPUArchState *env)
abort();
}
+ trace_kvm_run_exit(cpu->cpu_index, run->exit_reason);
switch (run->exit_reason) {
case KVM_EXIT_IO:
DPRINTF("handle_io\n");
@@ -1687,6 +1689,7 @@ int kvm_ioctl(KVMState *s, int type, ...)
arg = va_arg(ap, void *);
va_end(ap);
+ trace_kvm_ioctl(type, arg);
ret = ioctl(s->fd, type, arg);
if (ret == -1) {
ret = -errno;
@@ -1704,6 +1707,7 @@ int kvm_vm_ioctl(KVMState *s, int type, ...)
arg = va_arg(ap, void *);
va_end(ap);
+ trace_kvm_vm_ioctl(type, arg);
ret = ioctl(s->vmfd, type, arg);
if (ret == -1) {
ret = -errno;
@@ -1721,6 +1725,7 @@ int kvm_vcpu_ioctl(CPUState *cpu, int type, ...)
arg = va_arg(ap, void *);
va_end(ap);
+ trace_kvm_vcpu_ioctl(cpu->cpu_index, type, arg);
ret = ioctl(cpu->kvm_fd, type, arg);
if (ret == -1) {
ret = -errno;
diff --git a/scripts/tracetool/backend/ftrace.py b/scripts/tracetool/backend/ftrace.py
new file mode 100644
index 0000000..888c361
--- /dev/null
+++ b/scripts/tracetool/backend/ftrace.py
@@ -0,0 +1,54 @@
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+
+"""
+Ftrace built-in backend.
+"""
+
+__author__ = "Eiichi Tsukata <eiichi.tsukata.xh@hitachi.com>"
+__copyright__ = "Copyright (C) 2013 Hitachi, Ltd."
+__license__ = "GPL version 2 or (at your option) any later version"
+
+__maintainer__ = "Stefan Hajnoczi"
+__email__ = "stefanha@redhat.com"
+
+
+from tracetool import out
+
+
+PUBLIC = True
+
+
+def c(events):
+ pass
+
+def h(events):
+ out('#include "trace/ftrace.h"',
+ '#include "trace/control.h"',
+ '',
+ )
+
+ for e in events:
+ argnames = ", ".join(e.args.names())
+ if len(e.args) > 0:
+ argnames = ", " + argnames
+
+ out('static inline void trace_%(name)s(%(args)s)',
+ '{',
+ ' char ftrace_buf[MAX_TRACE_STRLEN];',
+ ' int unused __attribute__ ((unused));',
+ ' int trlen;',
+ ' bool _state = trace_event_get_state(%(event_id)s);',
+ ' if (_state) {',
+ ' trlen = snprintf(ftrace_buf, MAX_TRACE_STRLEN,',
+ ' "%(name)s " %(fmt)s "\\n" %(argnames)s);',
+ ' trlen = MIN(trlen, MAX_TRACE_STRLEN - 1);',
+ ' unused = write(trace_marker_fd, ftrace_buf, trlen);',
+ ' }',
+ '}',
+ name = e.name,
+ args = e.args,
+ event_id = "TRACE_" + e.name.upper(),
+ fmt = e.fmt.rstrip("\n"),
+ argnames = argnames,
+ )
diff --git a/trace-events b/trace-events
index 55e80be..17d75ab 100644
--- a/trace-events
+++ b/trace-events
@@ -1153,3 +1153,10 @@ virtio_ccw_new_device(int cssid, int ssid, int schid, int devno, const char *dev
# migration.c
migrate_set_state(int new_state) "new state %d"
+
+# kvm-all.c
+kvm_ioctl(int type, void *arg) "type %d, arg %p"
+kvm_vm_ioctl(int type, void *arg) "type %d, arg %p"
+kvm_vcpu_ioctl(int cpu_index, int type, void *arg) "cpu_index %d, type %d, arg %p"
+kvm_run_exit(int cpu_index, uint32_t reason) "cpu_index %d, reason %d"
+
diff --git a/trace/Makefile.objs b/trace/Makefile.objs
index a043072..3b88e49 100644
--- a/trace/Makefile.objs
+++ b/trace/Makefile.objs
@@ -76,5 +76,6 @@ endif
util-obj-$(CONFIG_TRACE_DEFAULT) += default.o
util-obj-$(CONFIG_TRACE_SIMPLE) += simple.o
util-obj-$(CONFIG_TRACE_STDERR) += stderr.o
+util-obj-$(CONFIG_TRACE_FTRACE) += ftrace.o
util-obj-y += control.o
util-obj-y += generated-tracers.o
diff --git a/trace/ftrace.c b/trace/ftrace.c
new file mode 100644
index 0000000..46b7fdb
--- /dev/null
+++ b/trace/ftrace.c
@@ -0,0 +1,102 @@
+/*
+ * Ftrace trace backend
+ *
+ * Copyright (C) 2013 Hitachi, Ltd.
+ * Created by Eiichi Tsukata <eiichi.tsukata.xh@hitachi.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2. See
+ * the COPYING file in the top-level directory.
+ *
+ */
+
+#include <stdio.h>
+#include <string.h>
+#include <fcntl.h>
+#include <limits.h>
+#include "trace.h"
+#include "trace/control.h"
+
+int trace_marker_fd;
+
+static int find_debugfs(char *debugfs)
+{
+ char type[100];
+ FILE *fp;
+
+ fp = fopen("/proc/mounts", "r");
+ if (fp == NULL) {
+ return 0;
+ }
+
+ while (fscanf(fp, "%*s %" STR(PATH_MAX) "s %99s %*s %*d %*d\n",
+ debugfs, type) == 2) {
+ if (strcmp(type, "debugfs") == 0) {
+ break;
+ }
+ }
+ fclose(fp);
+
+ if (strcmp(type, "debugfs") != 0) {
+ return 0;
+ }
+ return 1;
+}
+
+void trace_print_events(FILE *stream, fprintf_function stream_printf)
+{
+ TraceEventID i;
+
+ for (i = 0; i < trace_event_count(); i++) {
+ TraceEvent *ev = trace_event_id(i);
+ stream_printf(stream, "%s [Event ID %u] : state %u\n",
+ trace_event_get_name(ev), i, trace_event_get_state_dynamic(ev));
+ }
+}
+
+void trace_event_set_state_dynamic_backend(TraceEvent *ev, bool state)
+{
+ ev->dstate = state;
+}
+
+bool trace_backend_init(const char *events, const char *file)
+{
+ char debugfs[PATH_MAX];
+ char path[PATH_MAX];
+ int debugfs_found;
+ int trace_fd = -1;
+
+ if (file) {
+ fprintf(stderr, "error: -trace file=...: "
+ "option not supported by the selected tracing backend\n");
+ return false;
+ }
+
+ debugfs_found = find_debugfs(debugfs);
+ if (debugfs_found) {
+ snprintf(path, PATH_MAX, "%s/tracing/tracing_on", debugfs);
+ trace_fd = open(path, O_WRONLY);
+ if (trace_fd < 0) {
+ perror("Could not open ftrace 'tracing_on' file");
+ return false;
+ } else {
+ if (write(trace_fd, "1", 1) < 0) {
+ perror("Could not write to 'tracing_on' file");
+ close(trace_fd);
+ return false;
+ }
+ close(trace_fd);
+ }
+ snprintf(path, PATH_MAX, "%s/tracing/trace_marker", debugfs);
+ trace_marker_fd = open(path, O_WRONLY);
+ if (trace_marker_fd < 0) {
+ perror("Could not open ftrace 'trace_marker' file");
+ return false;
+ }
+ } else {
+ fprintf(stderr, "debugfs is not mounted\n");
+ return false;
+ }
+
+ trace_backend_init_events(events);
+ return true;
+}
diff --git a/trace/ftrace.h b/trace/ftrace.h
new file mode 100644
index 0000000..94cb8d5
--- /dev/null
+++ b/trace/ftrace.h
@@ -0,0 +1,10 @@
+#ifndef TRACE_FTRACE_H
+#define TRACE_FTRACE_H
+
+#define MAX_TRACE_STRLEN 512
+#define _STR(x) #x
+#define STR(x) _STR(x)
+
+extern int trace_marker_fd;
+
+#endif /* ! TRACE_FTRACE_H */
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