Merge tag 'pull-tcg-20230829-2' of https://gitlab.com/rth7680/qemu into staging

softmmu: Use async_run_on_cpu in tcg_commit
tcg: Remove vecop_list check from tcg_gen_not_vec
tcg/sparc64: Disable TCG_TARGET_HAS_extr_i64_i32
Revert "include/exec: typedef abi_ptr to vaddr in softmmu"

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* tag 'pull-tcg-20230829-2' of https://gitlab.com/rth7680/qemu:
  Revert "include/exec: typedef abi_ptr to vaddr in softmmu"
  tcg/sparc64: Disable TCG_TARGET_HAS_extr_i64_i32
  tcg: Remove vecop_list check from tcg_gen_not_vec
  softmmu: Use async_run_on_cpu in tcg_commit
  softmmu: Assert data in bounds in iotlb_to_section

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

7 files changed, 43 insertions, 62 deletions

diff --git a/accel/tcg/cpu-exec-common.c b/accel/tcg/cpu-exec-common.c
index 9a5fabf..7e35d7f 100644
--- a/accel/tcg/cpu-exec-common.c
+++ b/accel/tcg/cpu-exec-common.c
@@ -33,36 +33,6 @@ void cpu_loop_exit_noexc(CPUState *cpu)
     cpu_loop_exit(cpu);
 }
 
-#if defined(CONFIG_SOFTMMU)
-void cpu_reloading_memory_map(void)
-{
-    if (qemu_in_vcpu_thread() && current_cpu->running) {
-        /* The guest can in theory prolong the RCU critical section as long
-         * as it feels like. The major problem with this is that because it
-         * can do multiple reconfigurations of the memory map within the
-         * critical section, we could potentially accumulate an unbounded
-         * collection of memory data structures awaiting reclamation.
-         *
-         * Because the only thing we're currently protecting with RCU is the
-         * memory data structures, it's sufficient to break the critical section
-         * in this callback, which we know will get called every time the
-         * memory map is rearranged.
-         *
-         * (If we add anything else in the system that uses RCU to protect
-         * its data structures, we will need to implement some other mechanism
-         * to force TCG CPUs to exit the critical section, at which point this
-         * part of this callback might become unnecessary.)
-         *
-         * This pair matches cpu_exec's rcu_read_lock()/rcu_read_unlock(), which
-         * only protects cpu->as->dispatch. Since we know our caller is about
-         * to reload it, it's safe to split the critical section.
-         */
-        rcu_read_unlock();
-        rcu_read_lock();
-    }
-}
-#endif
-
 void cpu_loop_exit(CPUState *cpu)
 {
     /* Undo the setting in cpu_tb_exec.  */
diff --git a/include/exec/cpu-common.h b/include/exec/cpu-common.h
index 87dc9a7..41788c0 100644
--- a/include/exec/cpu-common.h
+++ b/include/exec/cpu-common.h
@@ -133,7 +133,6 @@ static inline void cpu_physical_memory_write(hwaddr addr,
 {
     cpu_physical_memory_rw(addr, (void *)buf, len, true);
 }
-void cpu_reloading_memory_map(void);
 void *cpu_physical_memory_map(hwaddr addr,
                               hwaddr *plen,
                               bool is_write);
diff --git a/include/exec/cpu_ldst.h b/include/exec/cpu_ldst.h
index f3ce4eb..da10ba1 100644
--- a/include/exec/cpu_ldst.h
+++ b/include/exec/cpu_ldst.h
@@ -121,8 +121,8 @@ static inline bool guest_range_valid_untagged(abi_ulong start, abi_ulong len)
     h2g_nocheck(x); \
 })
 #else
-typedef vaddr abi_ptr;
-#define TARGET_ABI_FMT_ptr "%016" VADDR_PRIx
+typedef target_ulong abi_ptr;
+#define TARGET_ABI_FMT_ptr TARGET_FMT_lx
 #endif
 
 uint32_t cpu_ldub_data(CPUArchState *env, abi_ptr ptr);
diff --git a/softmmu/physmem.c b/softmmu/physmem.c
index 3df7354..18277dd 100644
--- a/softmmu/physmem.c
+++ b/softmmu/physmem.c
@@ -680,8 +680,7 @@ address_space_translate_for_iotlb(CPUState *cpu, int asidx, hwaddr orig_addr,
     IOMMUTLBEntry iotlb;
     int iommu_idx;
     hwaddr addr = orig_addr;
-    AddressSpaceDispatch *d =
-        qatomic_rcu_read(&cpu->cpu_ases[asidx].memory_dispatch);
+    AddressSpaceDispatch *d = cpu->cpu_ases[asidx].memory_dispatch;
 
     for (;;) {
         section = address_space_translate_internal(d, addr, &addr, plen, false);
@@ -2412,10 +2411,16 @@ MemoryRegionSection *iotlb_to_section(CPUState *cpu,
 {
     int asidx = cpu_asidx_from_attrs(cpu, attrs);
     CPUAddressSpace *cpuas = &cpu->cpu_ases[asidx];
-    AddressSpaceDispatch *d = qatomic_rcu_read(&cpuas->memory_dispatch);
-    MemoryRegionSection *sections = d->map.sections;
+    AddressSpaceDispatch *d = cpuas->memory_dispatch;
+    int section_index = index & ~TARGET_PAGE_MASK;
+    MemoryRegionSection *ret;
+
+    assert(section_index < d->map.sections_nb);
+    ret = d->map.sections + section_index;
+    assert(ret->mr);
+    assert(ret->mr->ops);
 
-    return &sections[index & ~TARGET_PAGE_MASK];
+    return ret;
 }
 
 static void io_mem_init(void)
@@ -2481,23 +2486,42 @@ static void tcg_log_global_after_sync(MemoryListener *listener)
     }
 }
 
+static void tcg_commit_cpu(CPUState *cpu, run_on_cpu_data data)
+{
+    CPUAddressSpace *cpuas = data.host_ptr;
+
+    cpuas->memory_dispatch = address_space_to_dispatch(cpuas->as);
+    tlb_flush(cpu);
+}
+
 static void tcg_commit(MemoryListener *listener)
 {
     CPUAddressSpace *cpuas;
-    AddressSpaceDispatch *d;
+    CPUState *cpu;
 
     assert(tcg_enabled());
     /* since each CPU stores ram addresses in its TLB cache, we must
        reset the modified entries */
     cpuas = container_of(listener, CPUAddressSpace, tcg_as_listener);
-    cpu_reloading_memory_map();
-    /* The CPU and TLB are protected by the iothread lock.
-     * We reload the dispatch pointer now because cpu_reloading_memory_map()
-     * may have split the RCU critical section.
+    cpu = cpuas->cpu;
+
+    /*
+     * Defer changes to as->memory_dispatch until the cpu is quiescent.
+     * Otherwise we race between (1) other cpu threads and (2) ongoing
+     * i/o for the current cpu thread, with data cached by mmu_lookup().
+     *
+     * In addition, queueing the work function will kick the cpu back to
+     * the main loop, which will end the RCU critical section and reclaim
+     * the memory data structures.
+     *
+     * That said, the listener is also called during realize, before
+     * all of the tcg machinery for run-on is initialized: thus halt_cond.
      */
-    d = address_space_to_dispatch(cpuas->as);
-    qatomic_rcu_set(&cpuas->memory_dispatch, d);
-    tlb_flush(cpuas->cpu);
+    if (cpu->halt_cond) {
+        async_run_on_cpu(cpu, tcg_commit_cpu, RUN_ON_CPU_HOST_PTR(cpuas));
+    } else {
+        tcg_commit_cpu(cpu, RUN_ON_CPU_HOST_PTR(cpuas));
+    }
 }
 
 static void memory_map_init(void)
diff --git a/tcg/sparc64/tcg-target.c.inc b/tcg/sparc64/tcg-target.c.inc
index f2a346a..81a08bb 100644
--- a/tcg/sparc64/tcg-target.c.inc
+++ b/tcg/sparc64/tcg-target.c.inc
@@ -529,11 +529,6 @@ static void tcg_out_extu_i32_i64(TCGContext *s, TCGReg rd, TCGReg rs)
     tcg_out_ext32u(s, rd, rs);
 }
 
-static void tcg_out_extrl_i64_i32(TCGContext *s, TCGReg rd, TCGReg rs)
-{
-    tcg_out_mov(s, TCG_TYPE_I32, rd, rs);
-}
-
 static bool tcg_out_xchg(TCGContext *s, TCGType type, TCGReg r1, TCGReg r2)
 {
     return false;
@@ -1444,9 +1439,6 @@ static void tcg_out_op(TCGContext *s, TCGOpcode opc,
     case INDEX_op_divu_i64:
         c = ARITH_UDIVX;
         goto gen_arith;
-    case INDEX_op_extrh_i64_i32:
-        tcg_out_arithi(s, a0, a1, 32, SHIFT_SRLX);
-        break;
 
     case INDEX_op_brcond_i64:
         tcg_out_brcond_i64(s, a2, a0, a1, const_args[1], arg_label(args[3]));
@@ -1501,7 +1493,6 @@ static void tcg_out_op(TCGContext *s, TCGOpcode opc,
     case INDEX_op_ext32u_i64:
     case INDEX_op_ext_i32_i64:
     case INDEX_op_extu_i32_i64:
-    case INDEX_op_extrl_i64_i32:
     default:
         g_assert_not_reached();
     }
@@ -1533,8 +1524,6 @@ static TCGConstraintSetIndex tcg_target_op_def(TCGOpcode op)
     case INDEX_op_ext32u_i64:
     case INDEX_op_ext_i32_i64:
     case INDEX_op_extu_i32_i64:
-    case INDEX_op_extrl_i64_i32:
-    case INDEX_op_extrh_i64_i32:
     case INDEX_op_qemu_ld_a32_i32:
     case INDEX_op_qemu_ld_a64_i32:
     case INDEX_op_qemu_ld_a32_i64:
diff --git a/tcg/sparc64/tcg-target.h b/tcg/sparc64/tcg-target.h
index 3d41c96..5cfc4b4 100644
--- a/tcg/sparc64/tcg-target.h
+++ b/tcg/sparc64/tcg-target.h
@@ -115,7 +115,7 @@ extern bool use_vis3_instructions;
 #define TCG_TARGET_HAS_mulsh_i32        0
 #define TCG_TARGET_HAS_qemu_st8_i32     0
 
-#define TCG_TARGET_HAS_extr_i64_i32     1
+#define TCG_TARGET_HAS_extr_i64_i32     0
 #define TCG_TARGET_HAS_div_i64          1
 #define TCG_TARGET_HAS_rem_i64          0
 #define TCG_TARGET_HAS_rot_i64          0
diff --git a/tcg/tcg-op-vec.c b/tcg/tcg-op-vec.c
index ad8ee08..094298b 100644
--- a/tcg/tcg-op-vec.c
+++ b/tcg/tcg-op-vec.c
@@ -391,12 +391,11 @@ static bool do_op2(unsigned vece, TCGv_vec r, TCGv_vec a, TCGOpcode opc)
 
 void tcg_gen_not_vec(unsigned vece, TCGv_vec r, TCGv_vec a)
 {
-    const TCGOpcode *hold_list = tcg_swap_vecop_list(NULL);
-
-    if (!TCG_TARGET_HAS_not_vec || !do_op2(vece, r, a, INDEX_op_not_vec)) {
+    if (TCG_TARGET_HAS_not_vec) {
+        vec_gen_op2(INDEX_op_not_vec, 0, r, a);
+    } else {
         tcg_gen_xor_vec(0, r, a, tcg_constant_vec_matching(r, 0, -1));
     }
-    tcg_swap_vecop_list(hold_list);
 }
 
 void tcg_gen_neg_vec(unsigned vece, TCGv_vec r, TCGv_vec a)