plugins: implement inline operation relative to cpu_index

Instead of working on a fixed memory location, allow to address it based
on cpu_index, an element size and a given offset.
Result address: ptr + offset + cpu_index * element_size.

With this, we can target a member in a struct array from a base pointer.

Current semantic is not modified, thus inline operation still targets
always the same memory location.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Message-Id: <20240304130036.124418-4-pierrick.bouvier@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20240305121005.3528075-17-alex.bennee@linaro.org>

1 files changed, 8 insertions, 4 deletions

diff --git a/plugins/core.c b/plugins/core.c
index 63f4c6c6ce..65d5611f79 100644
--- a/plugins/core.c
+++ b/plugins/core.c
@@ -318,7 +318,8 @@ static struct qemu_plugin_dyn_cb *plugin_get_dyn_cb(GArray **arr)
 
 void plugin_register_inline_op(GArray **arr,
                                enum qemu_plugin_mem_rw rw,
-                               enum qemu_plugin_op op, void *ptr,
+                               enum qemu_plugin_op op,
+                               void *ptr,
                                uint64_t imm)
 {
     struct qemu_plugin_dyn_cb *dyn_cb;
@@ -474,9 +475,12 @@ void qemu_plugin_flush_cb(void)
     plugin_cb__simple(QEMU_PLUGIN_EV_FLUSH);
 }
 
-void exec_inline_op(struct qemu_plugin_dyn_cb *cb)
+void exec_inline_op(struct qemu_plugin_dyn_cb *cb, int cpu_index)
 {
-    uint64_t *val = cb->userp;
+    char *ptr = cb->userp;
+    size_t elem_size = 0;
+    size_t offset = 0;
+    uint64_t *val = (uint64_t *)(ptr + offset + cpu_index * elem_size);
 
     switch (cb->inline_insn.op) {
     case QEMU_PLUGIN_INLINE_ADD_U64:
@@ -509,7 +513,7 @@ void qemu_plugin_vcpu_mem_cb(CPUState *cpu, uint64_t vaddr,
                            vaddr, cb->userp);
             break;
         case PLUGIN_CB_INLINE:
-            exec_inline_op(cb);
+            exec_inline_op(cb, cpu->cpu_index);
             break;
         default:
             g_assert_not_reached();