tcg.patch

From b1f9d4395319e8ccab1e4fa8eb81a35075f18fb2 Mon Sep 17 00:00:00 2001
From: Khaos Tian <khaos.tian@gmail.com>
Date: Thu, 26 Nov 2020 16:45:39 -0800
Subject: [PATCH] TCG

---
 accel/tcg/cpu-exec.c      | 4 ++++
 accel/tcg/tcg-all.c       | 4 ++--
 accel/tcg/translate-all.c | 7 ++++++-
 3 files changed, 12 insertions(+), 3 deletions(-)

diff --git a/accel/tcg/cpu-exec.c b/accel/tcg/cpu-exec.c
index 58aea605d8..1294c9d908 100644
--- a/accel/tcg/cpu-exec.c
+++ b/accel/tcg/cpu-exec.c
@@ -365,6 +365,7 @@ static inline void tb_add_jump(TranslationBlock *tb, int n,
 {
     uintptr_t old;
 
+    pthread_jit_write_protect_np(false);
     assert(n < ARRAY_SIZE(tb->jmp_list_next));
     qemu_spin_lock(&tb_next->jmp_lock);
 
@@ -393,10 +394,12 @@ static inline void tb_add_jump(TranslationBlock *tb, int n,
                            "] index %d -> %p [" TARGET_FMT_lx "]\n",
                            tb->tc.ptr, tb->pc, n,
                            tb_next->tc.ptr, tb_next->pc);
+    pthread_jit_write_protect_np(true);
     return;
 
  out_unlock_next:
     qemu_spin_unlock(&tb_next->jmp_lock);
+    pthread_jit_write_protect_np(true);
     return;
 }
 
@@ -654,6 +657,7 @@ static inline void cpu_loop_exec_tb(CPUState *cpu, TranslationBlock *tb,
     uintptr_t ret;
     int32_t insns_left;
 
+    pthread_jit_write_protect_np(true);
     trace_exec_tb(tb, tb->pc);
     ret = cpu_tb_exec(cpu, tb);
     tb = (TranslationBlock *)(ret & ~TB_EXIT_MASK);
diff --git a/accel/tcg/tcg-all.c b/accel/tcg/tcg-all.c
index fa1208158f..72d414a970 100644
--- a/accel/tcg/tcg-all.c
+++ b/accel/tcg/tcg-all.c
@@ -101,11 +101,11 @@ bool mttcg_enabled;
 static int tcg_init(MachineState *ms)
 {
     TCGState *s = TCG_STATE(current_accel());
-
+    pthread_jit_write_protect_np(false);
     tcg_exec_init(s->tb_size * 1024 * 1024);
     mttcg_enabled = s->mttcg_enabled;
     cpus_register_accel(&tcg_cpus);
-
+    pthread_jit_write_protect_np(true);
     return 0;
 }
 
diff --git a/accel/tcg/translate-all.c b/accel/tcg/translate-all.c
index 4572b4901f..7287ea4275 100644
--- a/accel/tcg/translate-all.c
+++ b/accel/tcg/translate-all.c
@@ -1068,12 +1068,13 @@ static inline void *alloc_code_gen_buffer(void)
 static inline void *alloc_code_gen_buffer(void)
 {
     int prot = PROT_WRITE | PROT_READ | PROT_EXEC;
-    int flags = MAP_PRIVATE | MAP_ANONYMOUS;
+    int flags = MAP_JIT | MAP_PRIVATE | MAP_ANONYMOUS;
     size_t size = tcg_ctx->code_gen_buffer_size;
     void *buf;
 
     buf = mmap(NULL, size, prot, flags, -1, 0);
     if (buf == MAP_FAILED) {
+        fprintf(stderr, "mmap failed: %d\n", errno);
         return NULL;
     }
 
@@ -1485,7 +1486,9 @@ static void do_tb_phys_invalidate(TranslationBlock *tb, bool rm_from_page_list)
 
 static void tb_phys_invalidate__locked(TranslationBlock *tb)
 {
+    pthread_jit_write_protect_np(false);
     do_tb_phys_invalidate(tb, true);
+    pthread_jit_write_protect_np(true);
 }
 
 /* invalidate one TB
@@ -1675,6 +1678,7 @@ TranslationBlock *tb_gen_code(CPUState *cpu,
                               target_ulong pc, target_ulong cs_base,
                               uint32_t flags, int cflags)
 {
+    pthread_jit_write_protect_np(false);
     CPUArchState *env = cpu->env_ptr;
     TranslationBlock *tb, *existing_tb;
     tb_page_addr_t phys_pc, phys_page2;
@@ -1918,6 +1922,7 @@ TranslationBlock *tb_gen_code(CPUState *cpu,
         return existing_tb;
     }
     tcg_tb_insert(tb);
+    pthread_jit_write_protect_np(true);
     return tb;
 }
 
-- 
2.27.0

How would I apply this patch?

which qemu version corresponding to this patch？