diff --git a/cpu-exec.c b/cpu-exec.c index 2c0a6f642d..cb0c75d0d4 100644 --- a/cpu-exec.c +++ b/cpu-exec.c @@ -249,10 +249,10 @@ static void cpu_exec_nocache(CPUState *cpu, int max_cycles, tb_free(tb); } -static TranslationBlock *tb_find_slow(CPUState *cpu, - target_ulong pc, - target_ulong cs_base, - uint64_t flags) +static TranslationBlock *tb_find_physical(CPUState *cpu, + target_ulong pc, + target_ulong cs_base, + uint64_t flags) { CPUArchState *env = (CPUArchState *)cpu->env_ptr; TranslationBlock *tb, **ptb1; @@ -269,8 +269,9 @@ static TranslationBlock *tb_find_slow(CPUState *cpu, ptb1 = &tcg_ctx.tb_ctx.tb_phys_hash[h]; for(;;) { tb = *ptb1; - if (!tb) - goto not_found; + if (!tb) { + return NULL; + } if (tb->pc == pc && tb->page_addr[0] == phys_page1 && tb->cs_base == cs_base && @@ -282,25 +283,59 @@ static TranslationBlock *tb_find_slow(CPUState *cpu, virt_page2 = (pc & TARGET_PAGE_MASK) + TARGET_PAGE_SIZE; phys_page2 = get_page_addr_code(env, virt_page2); - if (tb->page_addr[1] == phys_page2) - goto found; + if (tb->page_addr[1] == phys_page2) { + break; + } } else { - goto found; + break; } } ptb1 = &tb->phys_hash_next; } - not_found: - /* if no translated code available, then translate it now */ + + /* Move the TB to the head of the list */ + *ptb1 = tb->phys_hash_next; + tb->phys_hash_next = tcg_ctx.tb_ctx.tb_phys_hash[h]; + tcg_ctx.tb_ctx.tb_phys_hash[h] = tb; + return tb; +} + +static TranslationBlock *tb_find_slow(CPUState *cpu, + target_ulong pc, + target_ulong cs_base, + uint64_t flags) +{ + TranslationBlock *tb; + + tb = tb_find_physical(cpu, pc, cs_base, flags); + if (tb) { + goto found; + } + +#ifdef CONFIG_USER_ONLY + /* mmap_lock is needed by tb_gen_code, and mmap_lock must be + * taken outside tb_lock. Since we're momentarily dropping + * tb_lock, there's a chance that our desired tb has been + * translated. + */ + tb_unlock(); + mmap_lock(); + tb_lock(); + tb = tb_find_physical(cpu, pc, cs_base, flags); + if (tb) { + mmap_unlock(); + goto found; + } +#endif + + /* if no translated code available, then translate it now */ tb = tb_gen_code(cpu, pc, cs_base, flags, 0); - found: - /* Move the last found TB to the head of the list */ - if (likely(*ptb1)) { - *ptb1 = tb->phys_hash_next; - tb->phys_hash_next = tcg_ctx.tb_ctx.tb_phys_hash[h]; - tcg_ctx.tb_ctx.tb_phys_hash[h] = tb; - } +#ifdef CONFIG_USER_ONLY + mmap_unlock(); +#endif + +found: /* we add the TB in the virtual pc hash table */ cpu->tb_jmp_cache[tb_jmp_cache_hash_func(pc)] = tb; return tb; diff --git a/translate-all.c b/translate-all.c index e3c5c5e20a..d9c7aac8e6 100644 --- a/translate-all.c +++ b/translate-all.c @@ -1375,6 +1375,8 @@ static inline void tb_alloc_page(TranslationBlock *tb, /* add a new TB and link it to the physical page tables. phys_page2 is * (-1) to indicate that only one page contains the TB. + * + * Called with mmap_lock held for user-mode emulation. */ static void tb_link_page(TranslationBlock *tb, tb_page_addr_t phys_pc, tb_page_addr_t phys_page2) @@ -1382,9 +1384,6 @@ static void tb_link_page(TranslationBlock *tb, tb_page_addr_t phys_pc, unsigned int h; TranslationBlock **ptb; - /* Grab the mmap lock to stop another thread invalidating this TB - before we are done. */ - mmap_lock(); /* add in the physical hash table */ h = tb_phys_hash_func(phys_pc); ptb = &tcg_ctx.tb_ctx.tb_phys_hash[h]; @@ -1414,7 +1413,6 @@ static void tb_link_page(TranslationBlock *tb, tb_page_addr_t phys_pc, #ifdef DEBUG_TB_CHECK tb_page_check(); #endif - mmap_unlock(); } /* find the TB 'tb' such that tb[0].tc_ptr <= tc_ptr <