plugins: new syscalls plugin

This commit adds a new syscalls plugin that displays the syscalls
as they are executed and returned. This plugin outputs the number
of the syscall as well as the syscall return value.

Works in *-user only.

Essentially, this commit restores:

  https://lists.gnu.org/archive/html/qemu-devel/2018-06/msg00846.html

by using the new QEMU plugin API.

Signed-off-by: Matthias Weckbecker <matthias@weckbecker.name>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20200812115816.4454-1-matthias@weckbecker.name>
Message-Id: <20210312172821.31647-2-alex.bennee@linaro.org>
This commit is contained in:
Matthias Weckbecker 2021-03-12 17:28:08 +00:00 committed by Alex Bennée
parent 6567ba0c60
commit 279d0a5b1e
2 changed files with 50 additions and 1 deletions

View file

@ -1,5 +1,5 @@
t = []
foreach i : ['bb', 'empty', 'insn', 'mem']
foreach i : ['bb', 'empty', 'insn', 'mem', 'syscall']
t += shared_module(i, files(i + '.c'),
include_directories: '../../include/qemu',
dependencies: glib)

49
tests/plugin/syscall.c Normal file
View file

@ -0,0 +1,49 @@
/*
* Copyright (C) 2020, Matthias Weckbecker <matthias@weckbecker.name>
*
* License: GNU GPL, version 2 or later.
* See the COPYING file in the top-level directory.
*/
#include <inttypes.h>
#include <assert.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <stdio.h>
#include <glib.h>
#include <qemu-plugin.h>
QEMU_PLUGIN_EXPORT int qemu_plugin_version = QEMU_PLUGIN_VERSION;
static void vcpu_syscall(qemu_plugin_id_t id, unsigned int vcpu_index,
int64_t num, uint64_t a1, uint64_t a2,
uint64_t a3, uint64_t a4, uint64_t a5,
uint64_t a6, uint64_t a7, uint64_t a8)
{
g_autofree gchar *out = g_strdup_printf("syscall #%" PRIi64 "\n", num);
qemu_plugin_outs(out);
}
static void vcpu_syscall_ret(qemu_plugin_id_t id, unsigned int vcpu_idx,
int64_t num, int64_t ret)
{
g_autofree gchar *out;
out = g_strdup_printf("syscall #%" PRIi64 " returned -> %" PRIi64 "\n",
num, ret);
qemu_plugin_outs(out);
}
/* ************************************************************************* */
static void plugin_exit(qemu_plugin_id_t id, void *p) {}
QEMU_PLUGIN_EXPORT int qemu_plugin_install(qemu_plugin_id_t id,
const qemu_info_t *info,
int argc, char **argv)
{
qemu_plugin_register_vcpu_syscall_cb(id, vcpu_syscall);
qemu_plugin_register_vcpu_syscall_ret_cb(id, vcpu_syscall_ret);
qemu_plugin_register_atexit_cb(id, plugin_exit, NULL);
return 0;
}