Richard Henderson <richard.hender...@linaro.org> writes:
> Wrap the bare TranslationBlock pointer into a structure.
>
> Reviewed-by: Philippe Mathieu-Daudé <f4...@amsat.org>
> Signed-off-by: Richard Henderson <richard.hender...@linaro.org>
> ---
> include/hw/core/cpu.h | 8 ++++++--
> accel/tcg/cpu-exec.c | 9 ++++++---
> accel/tcg/cputlb.c | 2 +-
> accel/tcg/translate-all.c | 4 ++--
> 4 files changed, 15 insertions(+), 8 deletions(-)
>
> diff --git a/include/hw/core/cpu.h b/include/hw/core/cpu.h
> index 9e47184513..ee5b75dea0 100644
> --- a/include/hw/core/cpu.h
> +++ b/include/hw/core/cpu.h
> @@ -232,6 +232,10 @@ struct hvf_vcpu_state;
> #define TB_JMP_CACHE_BITS 12
> #define TB_JMP_CACHE_SIZE (1 << TB_JMP_CACHE_BITS)
>
> +typedef struct {
> + TranslationBlock *tb;
> +} CPUJumpCache;
> +
I don't quite follow whats going on here. I see we add vaddr pc in a
later patch but I don't quite see why a cache for looking up TBs gets a
sidechan value added later.
Is this because the vaddr will no longer match the tb->pc? Maybe a
comment on the structure is needed?
> /* work queue */
>
> /* The union type allows passing of 64 bit target pointers on 32 bit
> @@ -361,7 +365,7 @@ struct CPUState {
> IcountDecr *icount_decr_ptr;
>
> /* Accessed in parallel; all accesses must be atomic */
> - TranslationBlock *tb_jmp_cache[TB_JMP_CACHE_SIZE];
> + CPUJumpCache tb_jmp_cache[TB_JMP_CACHE_SIZE];
>
> struct GDBRegisterState *gdb_regs;
> int gdb_num_regs;
> @@ -452,7 +456,7 @@ static inline void cpu_tb_jmp_cache_clear(CPUState *cpu)
> unsigned int i;
>
> for (i = 0; i < TB_JMP_CACHE_SIZE; i++) {
> - qatomic_set(&cpu->tb_jmp_cache[i], NULL);
> + qatomic_set(&cpu->tb_jmp_cache[i].tb, NULL);
> }
> }
>
> diff --git a/accel/tcg/cpu-exec.c b/accel/tcg/cpu-exec.c
> index dd58a144a8..c6283d5798 100644
> --- a/accel/tcg/cpu-exec.c
> +++ b/accel/tcg/cpu-exec.c
> @@ -252,7 +252,7 @@ static inline TranslationBlock *tb_lookup(CPUState *cpu,
> target_ulong pc,
> tcg_debug_assert(!(cflags & CF_INVALID));
>
> hash = tb_jmp_cache_hash_func(pc);
> - tb = qatomic_rcu_read(&cpu->tb_jmp_cache[hash]);
> + tb = qatomic_rcu_read(&cpu->tb_jmp_cache[hash].tb);
>
> if (likely(tb &&
> tb->pc == pc &&
> @@ -266,7 +266,7 @@ static inline TranslationBlock *tb_lookup(CPUState *cpu,
> target_ulong pc,
> if (tb == NULL) {
> return NULL;
> }
> - qatomic_set(&cpu->tb_jmp_cache[hash], tb);
> + qatomic_set(&cpu->tb_jmp_cache[hash].tb, tb);
> return tb;
> }
>
> @@ -987,6 +987,8 @@ int cpu_exec(CPUState *cpu)
>
> tb = tb_lookup(cpu, pc, cs_base, flags, cflags);
> if (tb == NULL) {
> + uint32_t h;
> +
> mmap_lock();
> tb = tb_gen_code(cpu, pc, cs_base, flags, cflags);
> mmap_unlock();
> @@ -994,7 +996,8 @@ int cpu_exec(CPUState *cpu)
> * We add the TB in the virtual pc hash table
> * for the fast lookup
> */
> - qatomic_set(&cpu->tb_jmp_cache[tb_jmp_cache_hash_func(pc)],
> tb);
> + h = tb_jmp_cache_hash_func(pc);
> + qatomic_set(&cpu->tb_jmp_cache[h].tb, tb);
> }
>
> #ifndef CONFIG_USER_ONLY
> diff --git a/accel/tcg/cputlb.c b/accel/tcg/cputlb.c
> index f5e6ca2da2..fb8f3087f1 100644
> --- a/accel/tcg/cputlb.c
> +++ b/accel/tcg/cputlb.c
> @@ -103,7 +103,7 @@ static void tb_jmp_cache_clear_page(CPUState *cpu,
> target_ulong page_addr)
> unsigned int i, i0 = tb_jmp_cache_hash_page(page_addr);
>
> for (i = 0; i < TB_JMP_PAGE_SIZE; i++) {
> - qatomic_set(&cpu->tb_jmp_cache[i0 + i], NULL);
> + qatomic_set(&cpu->tb_jmp_cache[i0 + i].tb, NULL);
> }
> }
>
> diff --git a/accel/tcg/translate-all.c b/accel/tcg/translate-all.c
> index f429d33981..efa479ccf3 100644
> --- a/accel/tcg/translate-all.c
> +++ b/accel/tcg/translate-all.c
> @@ -1187,8 +1187,8 @@ static void do_tb_phys_invalidate(TranslationBlock *tb,
> bool rm_from_page_list)
> /* remove the TB from the hash list */
> h = tb_jmp_cache_hash_func(tb->pc);
> CPU_FOREACH(cpu) {
> - if (qatomic_read(&cpu->tb_jmp_cache[h]) == tb) {
> - qatomic_set(&cpu->tb_jmp_cache[h], NULL);
> + if (qatomic_read(&cpu->tb_jmp_cache[h].tb) == tb) {
> + qatomic_set(&cpu->tb_jmp_cache[h].tb, NULL);
> }
> }
--
Alex Bennée
