used two-stage ll/sc

This commit is contained in:
joaquintides
2024-02-14 20:18:17 +01:00
parent b22c09700d
commit a08e86d985

View File

@ -553,7 +553,7 @@ public:
#if defined(BOOST_UNORDERED_LATCH_FREE)
~concurrent_table(){
std::cout
<<"version: 2024/02/12 13:40; "
<<"version: 2024/02/14 20:10; "
<<"lf: "<<(double)size()/capacity()<<"; "
<<"size: "<<size()<<", "
<<"capacity: "<<capacity()<<"; "
@ -869,17 +869,14 @@ public:
group_exclusive{},x,this->position_for(hash),hash,
[&,this](group_type* pg,unsigned int n,element_type* p)
{
if(f(cast_for(group_shared{},type_policy::value_from(*p)))){
//pg->reset(n);
auto pc=reinterpret_cast<std::atomic<unsigned char>*>(pg)+n;
auto c=pc->load(std::memory_order_relaxed);
if(c>1&&pc->compare_exchange_strong(c,0,std::memory_order_acq_rel)){
auto& sc=local_size_ctrl();
sc.size.fetch_sub(1,std::memory_order_relaxed);
sc.mcos.fetch_add(
!pg->is_not_overflowed(hash),std::memory_order_relaxed);
res=1;
}
if(/*is_occupied(pg,n)&&*/
f(cast_for(group_shared{},type_policy::value_from(*p)))){
pg->reset(n);
auto& sc=local_size_ctrl();
sc.size.fetch_sub(1,std::memory_order_relaxed);
sc.mcos.fetch_add(
!pg->is_not_overflowed(hash),std::memory_order_relaxed);
res=1;
}
});
return res;
@ -1275,9 +1272,8 @@ private:
#if defined(BOOST_UNORDERED_LATCH_FREE)
static bool is_occupied(group_type* pg,std::size_t pos)
{
//return reinterpret_cast<std::atomic<unsigned char>*>(pg)[pos].
// load(std::memory_order_acquire)>1;
return true;
return pg->is_occupied(pos);
//return true;
}
#else
static bool is_occupied(group_type* pg,std::size_t pos)
@ -1355,13 +1351,23 @@ private:
BOOST_UNORDERED_PREFETCH_ELEMENTS(p,N);
do{
auto n=unchecked_countr_zero(mask);
#if 0
auto [e,acnt]=load_access(pos,[&]{return *(p+n);});
#if 1
auto [pr,acnt]=load_access(pos,[&]{
return std::make_pair(is_occupied(pg,n),*(p+n));
});
auto [occupied,e]=pr;
if(!occupied)return 0;
if(BOOST_LIKELY(this->pred()(x,this->key_from(e)))){
if constexpr(std::is_same<GroupAccessMode,group_exclusive>::value){
// ALTERNATIVE: offline f(pg,n,&e)
if(!save_access(pos,acnt,[&]{f(pg,n,p+n);}))goto startover;
if(!save_access(pos,acnt,[&]{f(pg,n,p+n);})){
// SPECIFIC FOR erase: if the element changed, it can only be
// bc someone erased it.
// WATCH OUT: only approximate as acnt controls 15 elements,
// not just this one.
return 0;
}
return 1;
}else{
f(pg,n,&e);
@ -1737,26 +1743,38 @@ private:
auto mask=pg->match_available();
if(BOOST_LIKELY(mask!=0)){
auto n=unchecked_countr_zero(mask);
latch_free_reserve_slot rslot{pg,n};
if(BOOST_UNLIKELY(!rslot.succeeded())){
/* slot wasn't empty */
goto startover;
}
if(BOOST_UNLIKELY(
!insert_counter(pos0).compare_exchange_strong(
counter,counter+1,std::memory_order_relaxed))){
/* other thread inserted from pos0, need to start over */
goto startover;
}
//latch_free_reserve_slot rslot{pg,n};
//if(BOOST_UNLIKELY(!rslot.succeeded())){
// /* slot wasn't empty */
// goto startover;
//}
//if(BOOST_UNLIKELY(
// !insert_counter(pos0).compare_exchange_strong(
// counter,counter+1,std::memory_order_relaxed))){
// /* other thread inserted from pos0, need to start over */
// goto startover;
//}
{
assign_insert_counter_on_exit a{insert_counter(pos0),counter+2};
save_access(pos,[&]{
this->construct_element(
this->arrays.elements()+pos*N+n,std::forward<Args>(args)...);
});
pg->set(n,hash); // SHOULD GO INSIDE save_access?
//assign_insert_counter_on_exit a{insert_counter(pos0),counter+2};
auto [ocuppied,acnt]=load_access(pos,[&]{return is_occupied(pg,n);});
if(ocuppied)goto startover;
auto res=false;
if(!save_access(pos,acnt,[&]{
if(insert_counter(pos0).compare_exchange_strong(
counter,counter+1,std::memory_order_relaxed)){
assign_insert_counter_on_exit a{
insert_counter(pos0),counter+2};
this->construct_element(
this->arrays.elements()+pos*N+n,std::forward<Args>(args)...);
pg->set(n,hash);
res=true;
}
})||!res)goto startover;
}
rslot.commit();
//rslot.commit();
auto& sc=local_size_ctrl();
sc.size.fetch_add(1,std::memory_order_relaxed);
sc.mcos.fetch_sub(!pg->is_not_overflowed(hash),std::memory_order_relaxed);
@ -2086,6 +2104,7 @@ private:
mutable std::array<local_size_ctrl_type,128> local_size_ctrls;
std::atomic<std::size_t> max_probe=default_max_probe;
std::size_t rehashes=0;
//unsigned char paddd[64];
local_size_ctrl_type& local_size_ctrl()const
{