exec: introduce tlb_init

Paves the way for the addition of a per-TLB lock.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Message-Id: <20181009174557.16125-4-cota@braap.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

accel/tcg/cputlb.c

@@ -73,6 +73,10 @@ QEMU_BUILD_BUG_ON(sizeof(target_ulong) > sizeof(run_on_cpu_data));
 QEMU_BUILD_BUG_ON(NB_MMU_MODES > 16);
 #define ALL_MMUIDX_BITS ((1 << NB_MMU_MODES) - 1)
 
+void tlb_init(CPUState *cpu)
+{
+}
+
 /* flush_all_helper: run fn across all cpus
  *
  * If the wait flag is set then the src cpu's helper will be queued as

exec.c

@@ -965,6 +965,7 @@ void cpu_exec_realizefn(CPUState *cpu, Error **errp)
         tcg_target_initialized = true;
         cc->tcg_initialize();
     }
+    tlb_init(cpu);
 
 #ifndef CONFIG_USER_ONLY
     if (qdev_get_vmsd(DEVICE(cpu)) == NULL) {

include/exec/exec-all.h

@@ -99,6 +99,11 @@ void cpu_address_space_init(CPUState *cpu, int asidx,
 
 #if !defined(CONFIG_USER_ONLY) && defined(CONFIG_TCG)
 /* cputlb.c */
+/**
+ * tlb_init - initialize a CPU's TLB
+ * @cpu: CPU whose TLB should be initialized
+ */
+void tlb_init(CPUState *cpu);
 /**
  * tlb_flush_page:
  * @cpu: CPU whose TLB should be flushed
@@ -258,6 +263,9 @@ void tlb_set_page(CPUState *cpu, target_ulong vaddr,
 void probe_write(CPUArchState *env, target_ulong addr, int size, int mmu_idx,
                  uintptr_t retaddr);
 #else
+static inline void tlb_init(CPUState *cpu)
+{
+}
 static inline void tlb_flush_page(CPUState *cpu, target_ulong addr)
 {
 }