cputlb: Move NOTDIRTY handling from I/O path to TLB path

Pages that we want to track for NOTDIRTY are RAM.  We do not
really need to go through the I/O path to handle them.

Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

1 files changed, 23 insertions, 3 deletions

diff --git a/accel/tcg/cputlb.c b/accel/tcg/cputlb.c
index 404ec57..7e9a0f7 100644
--- a/accel/tcg/cputlb.c
+++ b/accel/tcg/cputlb.c
@@ -905,7 +905,7 @@ static uint64_t io_readx(CPUArchState *env, CPUIOTLBEntry *iotlbentry,
     mr = section->mr;
     mr_offset = (iotlbentry->addr & TARGET_PAGE_MASK) + addr;
     cpu->mem_io_pc = retaddr;
-    if (mr != &io_mem_notdirty && !cpu->can_do_io) {
+    if (!cpu->can_do_io) {
         cpu_io_recompile(cpu, retaddr);
     }
 
@@ -946,7 +946,7 @@ static void io_writex(CPUArchState *env, CPUIOTLBEntry *iotlbentry,
     section = iotlb_to_section(cpu, iotlbentry->addr, iotlbentry->attrs);
     mr = section->mr;
     mr_offset = (iotlbentry->addr & TARGET_PAGE_MASK) + addr;
-    if (mr != &io_mem_notdirty && !cpu->can_do_io) {
+    if (!cpu->can_do_io) {
         cpu_io_recompile(cpu, retaddr);
     }
     cpu->mem_io_vaddr = addr;
@@ -1612,7 +1612,7 @@ store_helper(CPUArchState *env, target_ulong addr, uint64_t val,
         need_swap = size > 1 && (tlb_addr & TLB_BSWAP);
 
         /* Handle I/O access.  */
-        if (likely(tlb_addr & (TLB_MMIO | TLB_NOTDIRTY))) {
+        if (tlb_addr & TLB_MMIO) {
             io_writex(env, iotlbentry, mmu_idx, val, addr, retaddr,
                       op ^ (need_swap * MO_BSWAP));
             return;
@@ -1625,6 +1625,26 @@ store_helper(CPUArchState *env, target_ulong addr, uint64_t val,
 
         haddr = (void *)((uintptr_t)addr + entry->addend);
 
+        /* Handle clean RAM pages.  */
+        if (tlb_addr & TLB_NOTDIRTY) {
+            NotDirtyInfo ndi;
+
+            /* We require mem_io_pc in tb_invalidate_phys_page_range.  */
+            env_cpu(env)->mem_io_pc = retaddr;
+
+            memory_notdirty_write_prepare(&ndi, env_cpu(env), addr,
+                                          addr + iotlbentry->addr, size);
+
+            if (unlikely(need_swap)) {
+                store_memop(haddr, val, op ^ MO_BSWAP);
+            } else {
+                store_memop(haddr, val, op);
+            }
+
+            memory_notdirty_write_complete(&ndi);
+            return;
+        }
+
         /*
          * Keep these two store_memop separate to ensure that the compiler
          * is able to fold the entire function to a single instruction.