commit 4a448b148ca076d80a41addd4fc1e49497cb23c8
author Pierrick Bouvier <pierrick.bouvier@linaro.org> Tue Feb 27 14:43:22 2024 +0000
committer Alex Bennée <alex.bennee@linaro.org> Wed Feb 28 09:11:36 2024 +0000
tree 73b2d9122e8921d125dabe0b94019751f7d570b1
parent 926e146eff8d7b89754e8b681f80e962d220f077

plugins: add qemu_plugin_num_vcpus function

We now keep track of how many vcpus were started. This way, a plugin can
easily query number of any vcpus at any point of execution, which
unifies user and system mode workflows.

Signed-off-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20240213094009.150349-3-pierrick.bouvier@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20240227144335.1196131-17-alex.bennee@linaro.org>

include/qemu/qemu-plugin.h

diff --git a/include/qemu/qemu-plugin.h b/include/qemu/qemu-plugin.h
index e45181c..93981f8 100644
--- a/include/qemu/qemu-plugin.h
+++ b/include/qemu/qemu-plugin.h
@@ -645,6 +645,9 @@
 void qemu_plugin_register_atexit_cb(qemu_plugin_id_t id,
                                     qemu_plugin_udata_cb_t cb, void *userdata);
 
+/* returns how many vcpus were started at this point */
+int qemu_plugin_num_vcpus(void);
+
 /**
  * qemu_plugin_outs() - output string via QEMU's logging system
  * @string: a string

plugins/api.c

diff --git a/plugins/api.c b/plugins/api.c
index 2926b19..116b8bd 100644
--- a/plugins/api.c
+++ b/plugins/api.c
@@ -342,6 +342,11 @@
 #endif
 }
 
+int qemu_plugin_num_vcpus(void)
+{
+    return plugin_num_vcpus();
+}
+
 /*
  * Plugin output
  */

plugins/core.c

diff --git a/plugins/core.c b/plugins/core.c
index ee2fa41..caa6631 100644
--- a/plugins/core.c
+++ b/plugins/core.c
@@ -213,6 +213,7 @@
     bool success;
 
     qemu_rec_mutex_lock(&plugin.lock);
+    plugin.num_vcpus = MAX(plugin.num_vcpus, cpu->cpu_index + 1);
     plugin_cpu_update__locked(&cpu->cpu_index, NULL, NULL);
     success = g_hash_table_insert(plugin.cpu_ht, &cpu->cpu_index,
                                   &cpu->cpu_index);
@@ -570,3 +571,8 @@
              QHT_MODE_AUTO_RESIZE);
     atexit(qemu_plugin_atexit_cb);
 }
+
+int plugin_num_vcpus(void)
+{
+    return plugin.num_vcpus;
+}

plugins/plugin.h

diff --git a/plugins/plugin.h b/plugins/plugin.h
index 90f3f32..00b3509 100644
--- a/plugins/plugin.h
+++ b/plugins/plugin.h
@@ -44,6 +44,8 @@
      * the code cache is flushed.
      */
     struct qht dyn_cb_arr_ht;
+    /* How many vcpus were started */
+    int num_vcpus;
 };
 
 
@@ -97,4 +99,6 @@
 
 void exec_inline_op(struct qemu_plugin_dyn_cb *cb);
 
+int plugin_num_vcpus(void);
+
 #endif /* PLUGIN_H */

plugins/qemu-plugins.symbols

diff --git a/plugins/qemu-plugins.symbols b/plugins/qemu-plugins.symbols
index ca80600..adb6760 100644
--- a/plugins/qemu-plugins.symbols
+++ b/plugins/qemu-plugins.symbols
@@ -16,6 +16,7 @@
   qemu_plugin_mem_is_sign_extended;
   qemu_plugin_mem_is_store;
   qemu_plugin_mem_size_shift;
+  qemu_plugin_num_vcpus;
   qemu_plugin_outs;
   qemu_plugin_path_to_binary;
   qemu_plugin_register_atexit_cb;