extend rb_call_cache

Prior to this changeset, majority of inline cache mishits resulted
into the same method entry when rb_callable_method_entry() resolves
a method search.  Let's not call the function at the first place on
such situations.

In doing so we extend the struct rb_call_cache from 44 bytes (in
case of 64 bit machine) to 64 bytes, and fill the gap with
secondary class serial(s).  Call cache's class serials now behavies
as a LRU cache.

Calculating -------------------------------------
                           ours         2.7         2.6
vm2_poly_same_method     2.339M      1.744M      1.369M i/s - 6.000M times in 2.565086s 3.441329s 4.381386s

Comparison:
             vm2_poly_same_method
                ours:   2339103.0 i/s
                 2.7:   1743512.3 i/s - 1.34x  slower
                 2.6:   1369429.8 i/s - 1.71x  slower
This commit is contained in:
卜部昌平 2019-10-07 12:59:57 +09:00
parent 3c252651e1
commit d45a013a1a
Notes: git 2019-11-07 17:41:56 +09:00
6 changed files with 75 additions and 19 deletions

View file

@ -1422,16 +1422,58 @@ rb_vm_search_method_slowpath(struct rb_call_data *cd, VALUE klass)
struct rb_call_cache *cc = &cd->cc;
const rb_callable_method_entry_t *me =
rb_callable_method_entry(klass, ci->mid);
*cc = (struct rb_call_cache) {
struct rb_call_cache buf = {
GET_GLOBAL_METHOD_STATE(),
RCLASS_SERIAL(klass),
{ RCLASS_SERIAL(klass) },
me,
me ? me->def : NULL,
calccall(cd, me),
};
if (buf.call != vm_call_general) {
for (int i = 0; i < numberof(cc->class_serial) - 1; i++) {
buf.class_serial[i + 1] = cc->class_serial[i];
}
}
MEMCPY(cc, &buf, struct rb_call_cache, 1);
VM_ASSERT(callable_method_entry_p(cc->me));
}
static inline bool
vm_cache_check_for_class_serial(struct rb_call_cache *cc, rb_serial_t class_serial)
{
int i;
rb_serial_t j;
for (i = 0; i < numberof(cc->class_serial); i++) {
j = cc->class_serial[i];
if (! j) {
break;
}
else if (j != class_serial) {
continue;
}
else if (! i) {
return true;
}
else {
goto hit;
}
}
RB_DEBUG_COUNTER_INC(mc_class_serial_miss);
return false;
hit:
for (; i > 0; i--) {
cc->class_serial[i] = cc->class_serial[i - 1];
}
cc->class_serial[0] = j;
MEMZERO(&cc->aux, cc->aux, 1); /* cc->call is valid, but cc->aux might not. */
return true;
}
static void
vm_search_method_fastpath(struct rb_call_data *cd, VALUE klass)
{
@ -1440,8 +1482,7 @@ vm_search_method_fastpath(struct rb_call_data *cd, VALUE klass)
#if OPT_INLINE_METHOD_CACHE
if (LIKELY(RB_DEBUG_COUNTER_INC_UNLESS(mc_global_state_miss,
GET_GLOBAL_METHOD_STATE() == cc->method_state) &&
RB_DEBUG_COUNTER_INC_UNLESS(mc_class_serial_miss,
RCLASS_SERIAL(klass) == cc->class_serial))) {
vm_cache_check_for_class_serial(cc, RCLASS_SERIAL(klass)))) {
/* cache hit! */
VM_ASSERT(cc->call != NULL);
RB_DEBUG_COUNTER_INC(mc_inline_hit);
@ -1605,24 +1646,16 @@ opt_eql_func(VALUE recv, VALUE obj, CALL_DATA cd)
VALUE
rb_equal_opt(VALUE obj1, VALUE obj2)
{
struct rb_call_data cd;
struct rb_call_data cd = { .ci = { .mid = idEq, }, };
cd.ci.mid = idEq;
cd.cc.method_state = 0;
cd.cc.class_serial = 0;
cd.cc.me = NULL;
return opt_eq_func(obj1, obj2, &cd);
}
VALUE
rb_eql_opt(VALUE obj1, VALUE obj2)
{
struct rb_call_data cd;
struct rb_call_data cd = { .ci = { .mid = idEqlP, }, };
cd.ci.mid = idEqlP;
cd.cc.method_state = 0;
cd.cc.class_serial = 0;
cd.cc.me = NULL;
return opt_eql_func(obj1, obj2, &cd);
}