plugins: remove previous n_vcpus functions from API

This information is already accessible using qemu_info_t during plugin
install.

We will introduce another function (qemu_plugin_num_vcpus) which
represent how many cpus were enabled, by tracking new cpu indexes.

It's a breaking change, so we bump API version.

Signed-off-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20240213094009.150349-2-pierrick.bouvier@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20240227144335.1196131-16-alex.bennee@linaro.org>

contrib/plugins/cache.c

@@ -767,7 +767,7 @@ int qemu_plugin_install(qemu_plugin_id_t id, const qemu_info_t *info,
 
     policy = LRU;
 
-    cores = sys ? qemu_plugin_n_vcpus() : 1;
+    cores = sys ? info->system.smp_vcpus : 1;
 
     for (i = 0; i < argc; i++) {
         char *opt = argv[i];

include/qemu/qemu-plugin.h

@@ -50,11 +50,13 @@ typedef uint64_t qemu_plugin_id_t;
  *
  * The plugins export the API they were built against by exposing the
  * symbol qemu_plugin_version which can be checked.
+ *
+ * version 2: removed qemu_plugin_n_vcpus and qemu_plugin_n_max_vcpus
  */
 
 extern QEMU_PLUGIN_EXPORT int qemu_plugin_version;
 
-#define QEMU_PLUGIN_VERSION 1
+#define QEMU_PLUGIN_VERSION 2
 
 /**
  * struct qemu_info_t - system information for plugins
@@ -643,12 +645,6 @@ QEMU_PLUGIN_API
 void qemu_plugin_register_atexit_cb(qemu_plugin_id_t id,
                                     qemu_plugin_udata_cb_t cb, void *userdata);
 
-/* returns -1 in user-mode */
-int qemu_plugin_n_vcpus(void);
-
-/* returns -1 in user-mode */
-int qemu_plugin_n_max_vcpus(void);
-
 /**
  * qemu_plugin_outs() - output string via QEMU's logging system
  * @string: a string

plugins/api.c

@@ -342,36 +342,6 @@ const char *qemu_plugin_hwaddr_device_name(const struct qemu_plugin_hwaddr *h)
 #endif
 }
 
-/*
- * Queries to the number and potential maximum number of vCPUs there
- * will be. This helps the plugin dimension per-vcpu arrays.
- */
-
-#ifndef CONFIG_USER_ONLY
-static MachineState * get_ms(void)
-{
-    return MACHINE(qdev_get_machine());
-}
-#endif
-
-int qemu_plugin_n_vcpus(void)
-{
-#ifdef CONFIG_USER_ONLY
-    return -1;
-#else
-    return get_ms()->smp.cpus;
-#endif
-}
-
-int qemu_plugin_n_max_vcpus(void)
-{
-#ifdef CONFIG_USER_ONLY
-    return -1;
-#else
-    return get_ms()->smp.max_cpus;
-#endif
-}
-
 /*
  * Plugin output
  */

plugins/plugin.h

@@ -15,7 +15,7 @@
 #include <gmodule.h>
 #include "qemu/qht.h"
 
-#define QEMU_PLUGIN_MIN_VERSION 0
+#define QEMU_PLUGIN_MIN_VERSION 2
 
 /* global state */
 struct qemu_plugin_state {

plugins/qemu-plugins.symbols

@@ -16,8 +16,6 @@
   qemu_plugin_mem_is_sign_extended;
   qemu_plugin_mem_is_store;
   qemu_plugin_mem_size_shift;
-  qemu_plugin_n_max_vcpus;
-  qemu_plugin_n_vcpus;
   qemu_plugin_outs;
   qemu_plugin_path_to_binary;
   qemu_plugin_register_atexit_cb;