1 files changed, 144 insertions, 0 deletions
diff --git a/tests/plugin/syscall.c b/tests/plugin/syscall.c
new file mode 100644
index 000000000..96040c578
--- /dev/null
+++ b/tests/plugin/syscall.c
@@ -0,0 +1,144 @@
+/*
+ * 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;
+
+typedef struct {
+    int64_t num;
+    int64_t calls;
+    int64_t errors;
+} SyscallStats;
+
+static GMutex lock;
+static GHashTable *statistics;
+
+static SyscallStats *get_or_create_entry(int64_t num)
+{
+    SyscallStats *entry =
+        (SyscallStats *) g_hash_table_lookup(statistics, GINT_TO_POINTER(num));
+
+    if (!entry) {
+        entry = g_new0(SyscallStats, 1);
+        entry->num = num;
+        g_hash_table_insert(statistics, GINT_TO_POINTER(num), (gpointer) entry);
+    }
+
+    return entry;
+}
+
+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)
+{
+    if (statistics) {
+        SyscallStats *entry;
+        g_mutex_lock(&lock);
+        entry = get_or_create_entry(num);
+        entry->calls++;
+        g_mutex_unlock(&lock);
+    } else {
+        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)
+{
+    if (statistics) {
+        SyscallStats *entry;
+
+        g_mutex_lock(&lock);
+        /* Should always return an existent entry. */
+        entry = get_or_create_entry(num);
+        if (ret < 0) {
+            entry->errors++;
+        }
+        g_mutex_unlock(&lock);
+    } else {
+        g_autofree gchar *out = g_strdup_printf(
+             "syscall #%" PRIi64 " returned -> %" PRIi64 "\n", num, ret);
+        qemu_plugin_outs(out);
+    }
+}
+
+static void print_entry(gpointer val, gpointer user_data)
+{
+    SyscallStats *entry = (SyscallStats *) val;
+    int64_t syscall_num = entry->num;
+    g_autofree gchar *out = g_strdup_printf(
+        "%-13" PRIi64 "%-6" PRIi64 " %" PRIi64 "\n",
+        syscall_num, entry->calls, entry->errors);
+    qemu_plugin_outs(out);
+}
+
+static gint comp_func(gconstpointer ea, gconstpointer eb)
+{
+    SyscallStats *ent_a = (SyscallStats *) ea;
+    SyscallStats *ent_b = (SyscallStats *) eb;
+
+    return ent_a->calls > ent_b->calls ? -1 : 1;
+}
+
+/* ************************************************************************* */
+static void plugin_exit(qemu_plugin_id_t id, void *p)
+{
+    if (!statistics) {
+        return;
+    }
+
+    g_mutex_lock(&lock);
+    GList *entries = g_hash_table_get_values(statistics);
+    entries = g_list_sort(entries, comp_func);
+    qemu_plugin_outs("syscall no.  calls  errors\n");
+
+    g_list_foreach(entries, print_entry, NULL);
+
+    g_list_free(entries);
+    g_hash_table_destroy(statistics);
+    g_mutex_unlock(&lock);
+}
+
+QEMU_PLUGIN_EXPORT int qemu_plugin_install(qemu_plugin_id_t id,
+                                           const qemu_info_t *info,
+                                           int argc, char **argv)
+{
+    bool do_print = false;
+
+    for (int i = 0; i < argc; i++) {
+        char *opt = argv[i];
+        g_autofree char **tokens = g_strsplit(opt, "=", 2);
+
+        if (g_strcmp0(tokens[0], "print") == 0) {
+            if (!qemu_plugin_bool_parse(tokens[0], tokens[1], &do_print)) {
+                fprintf(stderr, "boolean argument parsing failed: %s\n", opt);
+            }
+        } else {
+            fprintf(stderr, "unsupported argument: %s\n", argv[i]);
+            return -1;
+        }
+    }
+
+    if (!do_print) {
+        statistics = g_hash_table_new_full(NULL, g_direct_equal, NULL, g_free);
+    }
+
+    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;
+}