Speed up tlb_flush_page (Daniel Jacobowitz).

git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@2210 c046a42c-6fe2-441c-8c8c-71466251a162
This commit is contained in:
pbrook 2006-11-12 20:40:55 +00:00
parent d08b2a28e6
commit b362e5e067
3 changed files with 26 additions and 9 deletions

View File

@ -80,6 +80,14 @@ typedef unsigned long ram_addr_t;
#define TB_JMP_CACHE_BITS 12
#define TB_JMP_CACHE_SIZE (1 << TB_JMP_CACHE_BITS)
/* Only the bottom TB_JMP_PAGE_BITS of the jump cache hash bits vary for
addresses on the same page. The top bits are the same. This allows
TLB invalidation to quickly clear a subset of the hash table. */
#define TB_JMP_PAGE_BITS (TB_JMP_CACHE_BITS / 2)
#define TB_JMP_PAGE_SIZE (1 << TB_JMP_PAGE_BITS)
#define TB_JMP_ADDR_MASK (TB_JMP_PAGE_SIZE - 1)
#define TB_JMP_PAGE_MASK (TB_JMP_CACHE_SIZE - TB_JMP_PAGE_SIZE)
#define CPU_TLB_BITS 8
#define CPU_TLB_SIZE (1 << CPU_TLB_BITS)

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@ -196,9 +196,19 @@ typedef struct TranslationBlock {
struct TranslationBlock *jmp_first;
} TranslationBlock;
static inline unsigned int tb_jmp_cache_hash_page(target_ulong pc)
{
target_ulong tmp;
tmp = pc ^ (pc >> (TARGET_PAGE_BITS - TB_JMP_PAGE_BITS));
return (tmp >> TB_JMP_PAGE_BITS) & TB_JMP_PAGE_MASK;
}
static inline unsigned int tb_jmp_cache_hash_func(target_ulong pc)
{
return (pc ^ (pc >> TB_JMP_CACHE_BITS)) & (TB_JMP_CACHE_SIZE - 1);
target_ulong tmp;
tmp = pc ^ (pc >> (TARGET_PAGE_BITS - TB_JMP_PAGE_BITS));
return (((tmp >> TB_JMP_PAGE_BITS) & TB_JMP_PAGE_MASK) |
(tmp & TB_JMP_ADDR_MASK));
}
static inline unsigned int tb_phys_hash_func(unsigned long pc)

15
exec.c
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@ -1288,14 +1288,13 @@ void tlb_flush_page(CPUState *env, target_ulong addr)
tlb_flush_entry(&env->tlb_table[0][i], addr);
tlb_flush_entry(&env->tlb_table[1][i], addr);
for(i = 0; i < TB_JMP_CACHE_SIZE; i++) {
tb = env->tb_jmp_cache[i];
if (tb &&
((tb->pc & TARGET_PAGE_MASK) == addr ||
((tb->pc + tb->size - 1) & TARGET_PAGE_MASK) == addr)) {
env->tb_jmp_cache[i] = NULL;
}
}
/* Discard jump cache entries for any tb which might potentially
overlap the flushed page. */
i = tb_jmp_cache_hash_page(addr - TARGET_PAGE_SIZE);
memset (&env->tb_jmp_cache[i], 0, TB_JMP_PAGE_SIZE * sizeof(tb));
i = tb_jmp_cache_hash_page(addr);
memset (&env->tb_jmp_cache[i], 0, TB_JMP_PAGE_SIZE * sizeof(tb));
#if !defined(CONFIG_SOFTMMU)
if (addr < MMAP_AREA_END)