1 /*
2 * Copyright (C) 2020, Matthias Weckbecker <matthias@weckbecker.name>
3 *
4 * License: GNU GPL, version 2 or later.
5 * See the COPYING file in the top-level directory.
6 */
7 #include <inttypes.h>
8 #include <assert.h>
9 #include <stdlib.h>
10 #include <string.h>
11 #include <unistd.h>
12 #include <stdio.h>
13 #include <glib.h>
14
15 #include <qemu-plugin.h>
16
17 QEMU_PLUGIN_EXPORT int qemu_plugin_version = QEMU_PLUGIN_VERSION;
18
19 typedef struct {
20 int64_t num;
21 int64_t calls;
22 int64_t errors;
23 } SyscallStats;
24
25 static GMutex lock;
26 static GHashTable *statistics;
27
get_or_create_entry(int64_t num)28 static SyscallStats *get_or_create_entry(int64_t num)
29 {
30 SyscallStats *entry =
31 (SyscallStats *) g_hash_table_lookup(statistics, GINT_TO_POINTER(num));
32
33 if (!entry) {
34 entry = g_new0(SyscallStats, 1);
35 entry->num = num;
36 g_hash_table_insert(statistics, GINT_TO_POINTER(num), (gpointer) entry);
37 }
38
39 return entry;
40 }
41
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)42 static void vcpu_syscall(qemu_plugin_id_t id, unsigned int vcpu_index,
43 int64_t num, uint64_t a1, uint64_t a2,
44 uint64_t a3, uint64_t a4, uint64_t a5,
45 uint64_t a6, uint64_t a7, uint64_t a8)
46 {
47 if (statistics) {
48 SyscallStats *entry;
49 g_mutex_lock(&lock);
50 entry = get_or_create_entry(num);
51 entry->calls++;
52 g_mutex_unlock(&lock);
53 } else {
54 g_autofree gchar *out = g_strdup_printf("syscall #%" PRIi64 "\n", num);
55 qemu_plugin_outs(out);
56 }
57 }
58
vcpu_syscall_ret(qemu_plugin_id_t id,unsigned int vcpu_idx,int64_t num,int64_t ret)59 static void vcpu_syscall_ret(qemu_plugin_id_t id, unsigned int vcpu_idx,
60 int64_t num, int64_t ret)
61 {
62 if (statistics) {
63 SyscallStats *entry;
64
65 g_mutex_lock(&lock);
66 /* Should always return an existent entry. */
67 entry = get_or_create_entry(num);
68 if (ret < 0) {
69 entry->errors++;
70 }
71 g_mutex_unlock(&lock);
72 } else {
73 g_autofree gchar *out = g_strdup_printf(
74 "syscall #%" PRIi64 " returned -> %" PRIi64 "\n", num, ret);
75 qemu_plugin_outs(out);
76 }
77 }
78
print_entry(gpointer val,gpointer user_data)79 static void print_entry(gpointer val, gpointer user_data)
80 {
81 SyscallStats *entry = (SyscallStats *) val;
82 int64_t syscall_num = entry->num;
83 g_autofree gchar *out = g_strdup_printf(
84 "%-13" PRIi64 "%-6" PRIi64 " %" PRIi64 "\n",
85 syscall_num, entry->calls, entry->errors);
86 qemu_plugin_outs(out);
87 }
88
comp_func(gconstpointer ea,gconstpointer eb)89 static gint comp_func(gconstpointer ea, gconstpointer eb)
90 {
91 SyscallStats *ent_a = (SyscallStats *) ea;
92 SyscallStats *ent_b = (SyscallStats *) eb;
93
94 return ent_a->calls > ent_b->calls ? -1 : 1;
95 }
96
97 /* ************************************************************************* */
plugin_exit(qemu_plugin_id_t id,void * p)98 static void plugin_exit(qemu_plugin_id_t id, void *p)
99 {
100 if (!statistics) {
101 return;
102 }
103
104 g_mutex_lock(&lock);
105 GList *entries = g_hash_table_get_values(statistics);
106 entries = g_list_sort(entries, comp_func);
107 qemu_plugin_outs("syscall no. calls errors\n");
108
109 g_list_foreach(entries, print_entry, NULL);
110
111 g_list_free(entries);
112 g_hash_table_destroy(statistics);
113 g_mutex_unlock(&lock);
114 }
115
qemu_plugin_install(qemu_plugin_id_t id,const qemu_info_t * info,int argc,char ** argv)116 QEMU_PLUGIN_EXPORT int qemu_plugin_install(qemu_plugin_id_t id,
117 const qemu_info_t *info,
118 int argc, char **argv)
119 {
120 bool do_print = false;
121
122 for (int i = 0; i < argc; i++) {
123 char *opt = argv[i];
124 g_auto(GStrv) tokens = g_strsplit(opt, "=", 2);
125
126 if (g_strcmp0(tokens[0], "print") == 0) {
127 if (!qemu_plugin_bool_parse(tokens[0], tokens[1], &do_print)) {
128 fprintf(stderr, "boolean argument parsing failed: %s\n", opt);
129 }
130 } else {
131 fprintf(stderr, "unsupported argument: %s\n", argv[i]);
132 return -1;
133 }
134 }
135
136 if (!do_print) {
137 statistics = g_hash_table_new_full(NULL, g_direct_equal, NULL, g_free);
138 }
139
140 qemu_plugin_register_vcpu_syscall_cb(id, vcpu_syscall);
141 qemu_plugin_register_vcpu_syscall_ret_cb(id, vcpu_syscall_ret);
142 qemu_plugin_register_atexit_cb(id, plugin_exit, NULL);
143 return 0;
144 }
145