gdbstub: introduce gdb_get_max_cpus

This is needed for handling vcont packets as the way of calculating
max cpus vhanges between user and softmmu mode.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>

Message-Id: <20230302190846.2593720-17-alex.bennee@linaro.org>
Message-Id: <20230303025805.625589-17-richard.henderson@linaro.org>

gdbstub/gdbstub.c

@@ -624,16 +624,7 @@ static int gdb_handle_vcont(const char *p)
     GDBProcess *process;
     CPUState *cpu;
     GDBThreadIdKind kind;
-#ifdef CONFIG_USER_ONLY
-    int max_cpus = 1; /* global variable max_cpus exists only in system mode */
-
-    CPU_FOREACH(cpu) {
-        max_cpus = max_cpus <= cpu->cpu_index ? cpu->cpu_index + 1 : max_cpus;
-    }
-#else
-    MachineState *ms = MACHINE(qdev_get_machine());
-    unsigned int max_cpus = ms->smp.max_cpus;
-#endif
+    unsigned int max_cpus = gdb_get_max_cpus();
     /* uninitialised CPUs stay 0 */
     newstates = g_new0(char, max_cpus);
 

gdbstub/internals.h

@@ -129,6 +129,7 @@ bool gdb_got_immediate_ack(void);
 CPUState *gdb_first_attached_cpu(void);
 void gdb_append_thread_id(CPUState *cpu, GString *buf);
 int gdb_get_cpu_index(CPUState *cpu);
+unsigned int gdb_get_max_cpus(void); /* both */
 
 void gdb_create_default_process(GDBState *s);
 

gdbstub/softmmu.c

@@ -440,6 +440,15 @@ int gdb_target_memory_rw_debug(CPUState *cpu, hwaddr addr,
     return cpu_memory_rw_debug(cpu, addr, buf, len, is_write);
 }
 
+/*
+ * cpu helpers
+ */
+
+unsigned int gdb_get_max_cpus(void)
+{
+    MachineState *ms = MACHINE(qdev_get_machine());
+    return ms->smp.max_cpus;
+}
 
 /*
  * Softmmu specific command helpers

gdbstub/user.c

@@ -393,6 +393,23 @@ int gdb_target_memory_rw_debug(CPUState *cpu, hwaddr addr,
     return cpu_memory_rw_debug(cpu, addr, buf, len, is_write);
 }
 
+/*
+ * cpu helpers
+ */
+
+unsigned int gdb_get_max_cpus(void)
+{
+    CPUState *cpu;
+    unsigned int max_cpus = 1;
+
+    CPU_FOREACH(cpu) {
+        max_cpus = max_cpus <= cpu->cpu_index ? cpu->cpu_index + 1 : max_cpus;
+    }
+
+    return max_cpus;
+}
+
+
 /*
  * Break/Watch point helpers
  */