Commit 901bc3de authored by Sergey Fedorov's avatar Sergey Fedorov Committed by Richard Henderson
Browse files

tcg: Init TB's direct jumps before making it visible 



Initialize TB's direct jump list data fields and reset the jumps before
tb_link_page() puts it into the physical hash table and the physical
page list. So TB is completely initialized before it becomes visible.

This is pure rearrangement of code to a more suitable place, though it
could be a preparation for relaxing the locking scheme in future.

Signed-off-by: default avatarSergey Fedorov <serge.fdrv@gmail.com>
Signed-off-by: default avatarSergey Fedorov <sergey.fedorov@linaro.org>
Reviewed-by: default avatarAlex Bennée <alex.bennee@linaro.org>
Signed-off-by: default avatarRichard Henderson <rth@twiddle.net>
parent e90d96b1

translate-all.c

+19 −13
Original line number Diff line number Diff line
@@ -1134,19 +1134,6 @@ static void tb_link_page(TranslationBlock *tb, tb_page_addr_t phys_pc, 
        tb->page_addr[1] = -1;

    }



    assert(((uintptr_t)tb & 3) == 0);

    tb->jmp_list_first = (uintptr_t)tb | 2;

    tb->jmp_list_next[0] = (uintptr_t)NULL;

    tb->jmp_list_next[1] = (uintptr_t)NULL;



    /* init original jump addresses */

    if (tb->jmp_reset_offset[0] != TB_JMP_RESET_OFFSET_INVALID) {

        tb_reset_jump(tb, 0);

    }

    if (tb->jmp_reset_offset[1] != TB_JMP_RESET_OFFSET_INVALID) {

        tb_reset_jump(tb, 1);

    }



#ifdef DEBUG_TB_CHECK

    tb_page_check();

#endif
@@ -1255,12 +1242,31 @@ TranslationBlock *tb_gen_code(CPUState *cpu, 
        ROUND_UP((uintptr_t)gen_code_buf + gen_code_size + search_size,

                 CODE_GEN_ALIGN);



    /* init jump list */

    assert(((uintptr_t)tb & 3) == 0);

    tb->jmp_list_first = (uintptr_t)tb | 2;

    tb->jmp_list_next[0] = (uintptr_t)NULL;

    tb->jmp_list_next[1] = (uintptr_t)NULL;



    /* init original jump addresses wich has been set during tcg_gen_code() */

    if (tb->jmp_reset_offset[0] != TB_JMP_RESET_OFFSET_INVALID) {

        tb_reset_jump(tb, 0);

    }

    if (tb->jmp_reset_offset[1] != TB_JMP_RESET_OFFSET_INVALID) {

        tb_reset_jump(tb, 1);

    }



    /* check next page if needed */

    virt_page2 = (pc + tb->size - 1) & TARGET_PAGE_MASK;

    phys_page2 = -1;

    if ((pc & TARGET_PAGE_MASK) != virt_page2) {

        phys_page2 = get_page_addr_code(env, virt_page2);

    }

    /* As long as consistency of the TB stuff is provided by tb_lock in user

     * mode and is implicit in single-threaded softmmu emulation, no explicit

     * memory barrier is required before tb_link_page() makes the TB visible

     * through the physical hash table and physical page list.

     */

    tb_link_page(tb, phys_pc, phys_page2);

    return tb;

}