Re: [PATCH v4 03/57] accel/tcg: Introduce tlb_read_idx

[Peter Maydell]

On Fri, 5 May 2023 at 19:57, Richard Henderson
<richard.henderson@linaro.org> wrote:
>
> On 5/4/23 16:02, Peter Maydell wrote:
> > On Wed, 3 May 2023 at 08:15, Richard Henderson
> > <richard.henderson@linaro.org> wrote:
> >>
> >> Instead of playing with offsetof in various places, use
> >> MMUAccessType to index an array.  This is easily defined
> >> instead of the previous dummy padding array in the union.
> >>
> >> Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
> >> Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
> >> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
> >> ---
> >
> >> @@ -1802,7 +1763,8 @@ static void *atomic_mmu_lookup(CPUArchState *env, 
> >> target_ulong addr,
> >>       if (prot & PAGE_WRITE) {
> >>           tlb_addr = tlb_addr_write(tlbe);
> >>           if (!tlb_hit(tlb_addr, addr)) {
> >> -            if (!VICTIM_TLB_HIT(addr_write, addr)) {
> >> +            if (!victim_tlb_hit(env, mmu_idx, index, MMU_DATA_STORE,
> >> +                                addr & TARGET_PAGE_MASK)) {
> >>                   tlb_fill(env_cpu(env), addr, size,
> >>                            MMU_DATA_STORE, mmu_idx, retaddr);
> >>                   index = tlb_index(env, mmu_idx, addr);
> >> @@ -1835,7 +1797,8 @@ static void *atomic_mmu_lookup(CPUArchState *env, 
> >> target_ulong addr,
> >>       } else /* if (prot & PAGE_READ) */ {
> >>           tlb_addr = tlbe->addr_read;
>
> read
>
> >>           if (!tlb_hit(tlb_addr, addr)) {
> >> -            if (!VICTIM_TLB_HIT(addr_write, addr)) {
>
> write
>
> >> +            if (!victim_tlb_hit(env, mmu_idx, index, MMU_DATA_LOAD,
> >> +                                addr & TARGET_PAGE_MASK)) {
> >
> > This was previously looking at addr_write, but now we pass
> > MMU_DATA_LOAD ?
>
> This is the read portion of the read+write check.  The write portion is above 
> in the
> previous hunk.  So this is an existing error, fixed here, and I hadn't 
> noticed.

Yeah, I wondered if it was a pre-existing bug. We should split out
the bug fix.

-- PMM