tcg: Fold CPUTLBWindow into CPUTLBDesc

Both structures are allocated once per mmu_idx.
There is no reason for them to be separate.

Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

accel/tcg/cputlb.c

@@ -79,11 +79,11 @@ static inline size_t sizeof_tlb(CPUArchState *env, uintptr_t mmu_idx)
     return env->tlb_mask[mmu_idx] + (1 << CPU_TLB_ENTRY_BITS);
 }
 
-static void tlb_window_reset(CPUTLBWindow *window, int64_t ns,
+static void tlb_window_reset(CPUTLBDesc *desc, int64_t ns,
                              size_t max_entries)
 {
-    window->begin_ns = ns;
-    window->max_entries = max_entries;
+    desc->window_begin_ns = ns;
+    desc->window_max_entries = max_entries;
 }
 
 static void tlb_dyn_init(CPUArchState *env)
@@ -94,7 +94,7 @@ static void tlb_dyn_init(CPUArchState *env)
         CPUTLBDesc *desc = &env->tlb_d[i];
         size_t n_entries = 1 << CPU_TLB_DYN_DEFAULT_BITS;
 
-        tlb_window_reset(&desc->window, get_clock_realtime(), 0);
+        tlb_window_reset(desc, get_clock_realtime(), 0);
         desc->n_used_entries = 0;
         env->tlb_mask[i] = (n_entries - 1) << CPU_TLB_ENTRY_BITS;
         env->tlb_table[i] = g_new(CPUTLBEntry, n_entries);
@@ -151,18 +151,18 @@ static void tlb_mmu_resize_locked(CPUArchState *env, int mmu_idx)
     int64_t now = get_clock_realtime();
     int64_t window_len_ms = 100;
     int64_t window_len_ns = window_len_ms * 1000 * 1000;
-    bool window_expired = now > desc->window.begin_ns + window_len_ns;
+    bool window_expired = now > desc->window_begin_ns + window_len_ns;
 
-    if (desc->n_used_entries > desc->window.max_entries) {
-        desc->window.max_entries = desc->n_used_entries;
+    if (desc->n_used_entries > desc->window_max_entries) {
+        desc->window_max_entries = desc->n_used_entries;
     }
-    rate = desc->window.max_entries * 100 / old_size;
+    rate = desc->window_max_entries * 100 / old_size;
 
     if (rate > 70) {
         new_size = MIN(old_size << 1, 1 << CPU_TLB_DYN_MAX_BITS);
     } else if (rate < 30 && window_expired) {
-        size_t ceil = pow2ceil(desc->window.max_entries);
-        size_t expected_rate = desc->window.max_entries * 100 / ceil;
+        size_t ceil = pow2ceil(desc->window_max_entries);
+        size_t expected_rate = desc->window_max_entries * 100 / ceil;
 
         /*
          * Avoid undersizing when the max number of entries seen is just below
@@ -182,15 +182,15 @@ static void tlb_mmu_resize_locked(CPUArchState *env, int mmu_idx)
 
     if (new_size == old_size) {
         if (window_expired) {
-            tlb_window_reset(&desc->window, now, desc->n_used_entries);
+            tlb_window_reset(desc, now, desc->n_used_entries);
         }
         return;
     }
 
     g_free(env->tlb_table[mmu_idx]);
     g_free(env->iotlb[mmu_idx]);
 
-    tlb_window_reset(&desc->window, now, 0);
+    tlb_window_reset(desc, now, 0);
     /* desc->n_used_entries is cleared by the caller */
     env->tlb_mask[mmu_idx] = (new_size - 1) << CPU_TLB_ENTRY_BITS;
     env->tlb_table[mmu_idx] = g_try_new(CPUTLBEntry, new_size);

include/exec/cpu-defs.h

@@ -127,18 +127,6 @@ typedef struct CPUIOTLBEntry {
     MemTxAttrs attrs;
 } CPUIOTLBEntry;
 
-/**
- * struct CPUTLBWindow
- * @begin_ns: host time (in ns) at the beginning of the time window
- * @max_entries: maximum number of entries observed in the window
- *
- * See also: tlb_mmu_resize_locked()
- */
-typedef struct CPUTLBWindow {
-    int64_t begin_ns;
-    size_t max_entries;
-} CPUTLBWindow;
-
 typedef struct CPUTLBDesc {
     /*
      * Describe a region covering all of the large pages allocated
@@ -148,9 +136,12 @@ typedef struct CPUTLBDesc {
      */
     target_ulong large_page_addr;
     target_ulong large_page_mask;
+    /* host time (in ns) at the beginning of the time window */
+    int64_t window_begin_ns;
+    /* maximum number of entries observed in the window */
+    size_t window_max_entries;
     /* The next index to use in the tlb victim table.  */
     size_t vindex;
-    CPUTLBWindow window;
     size_t n_used_entries;
 } CPUTLBDesc;