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accel/tcg: Move jmp-cache CF_PCREL checks to caller

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tb-jmp-cache.h contains a few small functions that only exist to hide a
CF_PCREL check, however the caller often already performs such a check.

This patch moves CF_PCREL checks from the callee to the caller, and also
removes these functions which now only hide an access of the jmp-cache.

Signed-off-by: Anton Johansson <anjo@rev.ng>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20230227135202.9710-12-anjo@rev.ng>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This commit is contained in:
Anton Johansson 2023-02-27 14:51:46 +01:00 committed by Richard Henderson
parent f6680c5ea4
commit 2dd5b7a1b9
2 changed files with 40 additions and 50 deletions
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34
accel/tcg/cpu-exec.c
View File

@ -254,10 +254,13 @@ static inline TranslationBlock *tb_lookup(CPUState *cpu, target_ulong pc,
hash = tb_jmp_cache_hash_func(pc);
jc = cpu->tb_jmp_cache;
tb = tb_jmp_cache_get_tb(jc, cflags, hash);
if (cflags & CF_PCREL) {
/* Use acquire to ensure current load of pc from jc. */
tb = qatomic_load_acquire(&jc->array[hash].tb);
if (likely(tb &&
tb_jmp_cache_get_pc(jc, hash, tb) == pc &&
jc->array[hash].pc == pc &&
tb->cs_base == cs_base &&
tb->flags == flags &&
tb->trace_vcpu_dstate == *cpu->trace_dstate &&
@ -268,7 +271,29 @@ static inline TranslationBlock *tb_lookup(CPUState *cpu, target_ulong pc,
if (tb == NULL) {
return NULL;
}
tb_jmp_cache_set(jc, hash, tb, pc);
jc->array[hash].pc = pc;
/* Use store_release on tb to ensure pc is written first. */
qatomic_store_release(&jc->array[hash].tb, tb);
} else {
/* Use rcu_read to ensure current load of pc from *tb. */
tb = qatomic_rcu_read(&jc->array[hash].tb);
if (likely(tb &&
tb_pc(tb) == pc &&
tb->cs_base == cs_base &&
tb->flags == flags &&
tb->trace_vcpu_dstate == *cpu->trace_dstate &&
tb_cflags(tb) == cflags)) {
return tb;
}
tb = tb_htable_lookup(cpu, pc, cs_base, flags, cflags);
if (tb == NULL) {
return NULL;
}
/* Use the pc value already stored in tb->pc. */
qatomic_set(&jc->array[hash].tb, tb);
}
return tb;
}
@ -957,7 +982,8 @@ cpu_exec_loop(CPUState *cpu, SyncClocks *sc)
* for the fast lookup
*/
h = tb_jmp_cache_hash_func(pc);
tb_jmp_cache_set(cpu->tb_jmp_cache, h, tb, pc);
/* Use the pc value already stored in tb->pc. */
qatomic_set(&cpu->tb_jmp_cache->array[h].tb, tb);
}
#ifndef CONFIG_USER_ONLY

36
accel/tcg/tb-jmp-cache.h
View File

@ -25,40 +25,4 @@ struct CPUJumpCache {
} array[TB_JMP_CACHE_SIZE];
};
static inline TranslationBlock *
tb_jmp_cache_get_tb(CPUJumpCache *jc, uint32_t cflags, uint32_t hash)
{
if (cflags & CF_PCREL) {
/* Use acquire to ensure current load of pc from jc. */
return qatomic_load_acquire(&jc->array[hash].tb);
} else {
/* Use rcu_read to ensure current load of pc from *tb. */
return qatomic_rcu_read(&jc->array[hash].tb);
}
}
static inline target_ulong
tb_jmp_cache_get_pc(CPUJumpCache *jc, uint32_t hash, TranslationBlock *tb)
{
if (tb_cflags(tb) & CF_PCREL) {
return jc->array[hash].pc;
} else {
return tb_pc(tb);
}
}
static inline void
tb_jmp_cache_set(CPUJumpCache *jc, uint32_t hash,
TranslationBlock *tb, target_ulong pc)
{
if (tb_cflags(tb) & CF_PCREL) {
jc->array[hash].pc = pc;
/* Use store_release on tb to ensure pc is written first. */
qatomic_store_release(&jc->array[hash].tb, tb);
} else{
/* Use the pc value already stored in tb->pc. */
qatomic_set(&jc->array[hash].tb, tb);
}
}
#endif /* ACCEL_TCG_TB_JMP_CACHE_H */