[PATCH 2/9] accel/tcg: Pass length argument to tlb_flush_range_locked()

["Philippe Mathieu-Daudé" <f4bug@amsat.org>]

From: Richard Henderson <richard.henderson@linaro.org>

Rename tlb_flush_page_bits_locked() -> tlb_flush_range_locked(), and
have callers pass a length argument (currently TARGET_PAGE_SIZE) via
the TLBFlushPageBitsByMMUIdxData structure.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20210508201640.1045808-1-richard.henderson@linaro.org>
[PMD: Split from bigger patch]
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
---
 accel/tcg/cputlb.c | 48 +++++++++++++++++++++++++++++++---------------
 1 file changed, 33 insertions(+), 15 deletions(-)

diff --git a/accel/tcg/cputlb.c b/accel/tcg/cputlb.c
index f616b58a898..df5d5dbf879 100644
--- a/accel/tcg/cputlb.c
+++ b/accel/tcg/cputlb.c
@@ -707,8 +707,9 @@ void tlb_flush_page_all_cpus_synced(CPUState *src, target_ulong addr)
     tlb_flush_page_by_mmuidx_all_cpus_synced(src, addr, ALL_MMUIDX_BITS);
 }
 
-static void tlb_flush_page_bits_locked(CPUArchState *env, int midx,
-                                       target_ulong page, unsigned bits)
+static void tlb_flush_range_locked(CPUArchState *env, int midx,
+                                   target_ulong addr, target_ulong len,
+                                   unsigned bits)
 {
     CPUTLBDesc *d = &env_tlb(env)->d[midx];
     CPUTLBDescFast *f = &env_tlb(env)->f[midx];
@@ -718,20 +719,26 @@ static void tlb_flush_page_bits_locked(CPUArchState *env, int midx,
      * If @bits is smaller than the tlb size, there may be multiple entries
      * within the TLB; otherwise all addresses that match under @mask hit
      * the same TLB entry.
-     *
      * TODO: Perhaps allow bits to be a few bits less than the size.
      * For now, just flush the entire TLB.
+     *
+     * If @len is larger than the tlb size, then it will take longer to
+     * test all of the entries in the TLB than it will to flush it all.
      */
-    if (mask < f->mask) {
+    if (mask < f->mask || len > f->mask) {
         tlb_debug("forcing full flush midx %d ("
-                  TARGET_FMT_lx "/" TARGET_FMT_lx ")\n",
-                  midx, page, mask);
+                  TARGET_FMT_lx "/" TARGET_FMT_lx "+" TARGET_FMT_lx ")\n",
+                  midx, addr, mask, len);
         tlb_flush_one_mmuidx_locked(env, midx, get_clock_realtime());
         return;
     }
 
-    /* Check if we need to flush due to large pages.  */
-    if ((page & d->large_page_mask) == d->large_page_addr) {
+    /*
+     * Check if we need to flush due to large pages.
+     * Because large_page_mask contains all 1's from the msb,
+     * we only need to test the end of the range.
+     */
+    if (((addr + len - 1) & d->large_page_mask) == d->large_page_addr) {
         tlb_debug("forcing full flush midx %d ("
                   TARGET_FMT_lx "/" TARGET_FMT_lx ")\n",
                   midx, d->large_page_addr, d->large_page_mask);
@@ -739,14 +746,20 @@ static void tlb_flush_page_bits_locked(CPUArchState *env, int midx,
         return;
     }
 
-    if (tlb_flush_entry_mask_locked(tlb_entry(env, midx, page), page, mask)) {
-        tlb_n_used_entries_dec(env, midx);
+    for (target_ulong i = 0; i < len; i += TARGET_PAGE_SIZE) {
+        target_ulong page = addr + i;
+        CPUTLBEntry *entry = tlb_entry(env, midx, page);
+
+        if (tlb_flush_entry_mask_locked(entry, page, mask)) {
+            tlb_n_used_entries_dec(env, midx);
+        }
+        tlb_flush_vtlb_page_mask_locked(env, midx, page, mask);
     }
-    tlb_flush_vtlb_page_mask_locked(env, midx, page, mask);
 }
 
 typedef struct {
     target_ulong addr;
+    target_ulong len;
     uint16_t idxmap;
     uint16_t bits;
 } TLBFlushPageBitsByMMUIdxData;
@@ -760,18 +773,20 @@ tlb_flush_page_bits_by_mmuidx_async_0(CPUState *cpu,
 
     assert_cpu_is_self(cpu);
 
-    tlb_debug("page addr:" TARGET_FMT_lx "/%u mmu_map:0x%x\n",
-              d.addr, d.bits, d.idxmap);
+    tlb_debug("range:" TARGET_FMT_lx "/%u+" TARGET_FMT_lx " mmu_map:0x%x\n",
+              d.addr, d.bits, d.len, d.idxmap);
 
     qemu_spin_lock(&env_tlb(env)->c.lock);
     for (mmu_idx = 0; mmu_idx < NB_MMU_MODES; mmu_idx++) {
         if ((d.idxmap >> mmu_idx) & 1) {
-            tlb_flush_page_bits_locked(env, mmu_idx, d.addr, d.bits);
+            tlb_flush_range_locked(env, mmu_idx, d.addr, d.len, d.bits);
         }
     }
     qemu_spin_unlock(&env_tlb(env)->c.lock);
 
-    tb_flush_jmp_cache(cpu, d.addr);
+    for (target_ulong i = 0; i < d.len; i += TARGET_PAGE_SIZE) {
+        tb_flush_jmp_cache(cpu, d.addr + i);
+    }
 }
 
 static bool encode_pbm_to_runon(run_on_cpu_data *out,
@@ -829,6 +844,7 @@ void tlb_flush_page_bits_by_mmuidx(CPUState *cpu, target_ulong addr,
 
     /* This should already be page aligned */
     d.addr = addr & TARGET_PAGE_MASK;
+    d.len = TARGET_PAGE_SIZE;
     d.idxmap = idxmap;
     d.bits = bits;
 
@@ -865,6 +881,7 @@ void tlb_flush_page_bits_by_mmuidx_all_cpus(CPUState *src_cpu,
 
     /* This should already be page aligned */
     d.addr = addr & TARGET_PAGE_MASK;
+    d.len = TARGET_PAGE_SIZE;
     d.idxmap = idxmap;
     d.bits = bits;
 
@@ -908,6 +925,7 @@ void tlb_flush_page_bits_by_mmuidx_all_cpus_synced(CPUState *src_cpu,
 
     /* This should already be page aligned */
     d.addr = addr & TARGET_PAGE_MASK;
+    d.len = TARGET_PAGE_SIZE;
     d.idxmap = idxmap;
     d.bits = bits;
 
-- 
2.26.3