There is no real need to use CF_NOCACHE here. As long as the TB isn't linked to other TBs or included in the QHT or jump cache then it will only get executed once.
Signed-off-by: Alex Bennée <alex.ben...@linaro.org> Message-Id: <20210209182749.31323-10-alex.ben...@linaro.org> --- accel/tcg/translate-all.c | 30 +++++++++++++++--------------- 1 file changed, 15 insertions(+), 15 deletions(-) diff --git a/accel/tcg/translate-all.c b/accel/tcg/translate-all.c index b8ad95aa1b..7e62d8ad97 100644 --- a/accel/tcg/translate-all.c +++ b/accel/tcg/translate-all.c @@ -1778,7 +1778,8 @@ static inline void tb_page_add(PageDesc *p, TranslationBlock *tb, #endif } -/* add a new TB and link it to the physical page tables. phys_page2 is +/* + * 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. @@ -1797,17 +1798,6 @@ tb_link_page(TranslationBlock *tb, tb_page_addr_t phys_pc, assert_memory_lock(); - if (phys_pc == -1) { - /* - * If the TB is not associated with a physical RAM page then - * it must be a temporary one-insn TB, and we have nothing to do - * except fill in the page_addr[] fields. - */ - assert(tb->cflags & CF_NOCACHE); - tb->page_addr[0] = tb->page_addr[1] = -1; - return tb; - } - /* * Add the TB to the page list, acquiring first the pages's locks. * We keep the locks held until after inserting the TB in the hash table, @@ -1880,9 +1870,8 @@ TranslationBlock *tb_gen_code(CPUState *cpu, phys_pc = get_page_addr_code(env, pc); if (phys_pc == -1) { - /* Generate a temporary TB with 1 insn in it */ - cflags &= ~CF_COUNT_MASK; - cflags |= CF_NOCACHE | 1; + /* Generate a one-shot TB with 1 insn in it */ + cflags = (cflags & ~CF_COUNT_MASK) | 1; } cflags &= ~CF_CLUSTER_MASK; @@ -2096,6 +2085,17 @@ TranslationBlock *tb_gen_code(CPUState *cpu, tb_reset_jump(tb, 1); } + /* + * If the TB is not associated with a physical RAM page then + * it must be a temporary one-insn TB, and we have nothing to do + * except fill in the page_addr[] fields. Return early before + * attempting to link to other TBs or add to the lookup table. + */ + if (phys_pc == -1) { + tb->page_addr[0] = tb->page_addr[1] = -1; + return tb; + } + /* check next page if needed */ virt_page2 = (pc + tb->size - 1) & TARGET_PAGE_MASK; phys_page2 = -1; -- 2.20.1