struct mpmc_boundq_1_alt
{
private:
-
+
+ unsigned int MASK;
+
+ atomic<t_element*> arr;
+
// elements should generally be cache-line-size padded :
t_element m_array[t_size];
public:
- mpmc_boundq_1_alt()
+ mpmc_boundq_1_alt(int _MASK = 0xFFFF)
{
/**
@Begin
m_rdwr = 0;
m_read = 0;
m_written = 0;
+ // For this we want MASK = 1; MASK wrap around
+ MASK = _MASK; //0x11;
+ arr = m_array;
}
LANG = CPP;
CLASS = mpmc_boundq_1_alt;
@Global_define:
- @DeclareStruct:
- typedef struct elem {
- t_element *pos;
- bool written;
- thread_id_t tid;
- thread_id_t fetch_tid;
- call_id_t id;
- } elem;
- @DeclareVar:
- spec_list *list;
- //id_tag_t *tag;
- @InitVar:
- list = new_spec_list();
- //tag = new_id_tag();
- @Happens_before:
- Publish -> Fetch
- Consume -> Prepare
+ @Happens_before:
+ Publish -> Fetch
+ Consume -> Prepare
+ @Commutativity: Prepare <-> Prepare: _Method1.__RET__ !=
+ _Method2.__RET__ || !_Method1.__RET__ || !_Method2.__RET__
+ @Commutativity: Prepare <-> Publish: _Method1.__RET__ != _Method2.bin ||
+ !_Method1.__RET__
+ @Commutativity: Prepare <-> Fetch: _Method1.__RET__ != _Method2.__RET__
+ || !_Method1.__RET__ || !_Method2.__RET__
+ @Commutativity: Prepare <-> Consume : _Method1.__RET__ != _Method2.bin || !_Method1.__RET__
+
+ @Commutativity: Publish <-> Publish: _Method1.bin != _Method2.bin
+ @Commutativity: Publish <-> Fetch: _Method1.bin != _Method2.__RET__ ||
+ !_Method2.__RET__
+ @Commutativity: Publish <-> Consume : _Method1.bin != _Method2.bin
+
+ @Commutativity: Fetch <-> Fetch: _Method1.__RET__ != _Method2.__RET__ ||
+ !_Method1.__RET__ || !_Method2.__RET__
+ @Commutativity: Fetch <-> Consume : _Method1.__RET__ != _Method2.bin || !_Method1.__RET__
+
+ @Commutativity: Consume <-> Consume : _Method1.bin != _Method2.bin
+
@End
*/
/**
@Begin
@Interface: Fetch
- @Commit_point_set: Fetch_Empty_Point | Fetch_Succ_Point
+ @Commit_point_set: FetchReadRW1 | FetchReadRW2 | FetchReadPointer
@ID: (call_id_t) __RET__
- //@Check:
- //__RET__ == NULL || has_elem(list, __RET__)
+ //@Action: model_print("Fetch: %d\n", __RET__);
@End
*/
t_element * read_fetch() {
- // Try this new weaker semantics
+ // Since we have a lool to CAS the value of m_rdwr, this can be relaxed
unsigned int rdwr = m_rdwr.load(mo_acquire);
//unsigned int rdwr = m_rdwr.load(mo_relaxed);
/**
@Begin
- @Potential_commit_point_define: true
- @Label: Fetch_Potential_Point
+ @Commit_point_define_check: true
+ @Label: FetchReadRW1
@End
*/
unsigned int rd,wr;
for(;;) {
- rd = (rdwr>>16) & 0xFFFF;
- wr = rdwr & 0xFFFF;
+ rd = (rdwr>>16) & MASK;
+ wr = rdwr & MASK;
if ( wr == rd ) { // empty
-
+ return false;
+ }
+ /**** Inadmissibility (testcase2.cc, MASK = 1, size = 1) ****/
+ bool succ =
+ m_rdwr.compare_exchange_weak(rdwr,rdwr+(1<<16),mo_acq_rel);
+ if (succ) {
+ break;
+ } else {
/**
@Begin
- @Commit_point_define: true
- @Potential_commit_point_label: Fetch_Potential_Point
- @Label: Fetch_Empty_Point
+ @Commit_point_clear: true
+ @Label: FetchClear1
@End
*/
- return false;
- }
-
- bool succ = m_rdwr.compare_exchange_weak(rdwr,rdwr+(1<<16),mo_acq_rel);
- /**
- @Begin
- @Commit_point_define_check: succ == true
- @Label: Fetch_Succ_Point
- @End
- */
- if (succ)
- break;
- else
+ /**
+ @Begin
+ @Commit_point_define_check: true
+ @Label: FetchReadRW2
+ @End
+ */
thrd_yield();
+ }
}
// (*1)
rl::backoff bo;
- while ( (m_written.load(mo_acquire) & 0xFFFF) != wr ) {
- thrd_yield();
+ while (true) {
+ /**** Inadmissibility ****/
+ int written = m_written.load(mo_acquire);
+ if ((written & MASK) != wr) {
+ thrd_yield();
+ } else {
+ printf("Fetch: m_written=%d\n", written);
+ break;
+ }
}
-
t_element * p = & ( m_array[ rd % t_size ] );
+
+ // This is just a hack to tell the CDSChecker that we have a memory
+ // operation here
+ arr.load(memory_order_relaxed);
+ /**
+ @Begin
+ @Commit_point_clear: true
+ @Label: FetchClear2
+ @End
+ */
+ /**
+ @Begin
+ @Commit_point_define_check: true
+ @Label: FetchReadPointer
+ @End
+ */
return p;
}
/**
@Begin
@Interface: Consume
- @Commit_point_set: Consume_Point
+ @Commit_point_set: ConsumeFetchAdd
@ID: (call_id_t) bin
- //@Check:
- // consume_check(__TID__)
- //@Action:
- //consume(__TID__);
+ //@Action: model_print("Consume: %d\n", bin);
@End
*/
void read_consume(t_element *bin) {
- /**** FIXME: miss ****/
+ /**** Inadmissibility ****/
m_read.fetch_add(1,mo_release);
/**
@Begin
@Commit_point_define_check: true
- @Label: Consume_Point
+ @Label: ConsumeFetchAdd
@End
*/
}
/**
@Begin
@Interface: Prepare
- @Commit_point_set: Prepare_Full_Point | Prepare_Succ_Point
+ @Commit_point_set: PrepareReadRW1 | PrepareReadRW2 | PrepareReadPointer
@ID: (call_id_t) __RET__
- //@Check:
- //prepare_check(__RET__, __TID__)
- //@Action:
- //push_back(list, __RET__);
+ //@Action: model_print("Prepare: %d\n", __RET__);
@End
*/
t_element * write_prepare() {
// Try weaker semantics
+ // Since we have a lool to CAS the value of m_rdwr, this can be relaxed
unsigned int rdwr = m_rdwr.load(mo_acquire);
//unsigned int rdwr = m_rdwr.load(mo_relaxed);
/**
@Begin
- @Potential_commit_point_define: true
- @Label: Prepare_Potential_Point
+ @Commit_point_define_check: true
+ @Label: PrepareReadRW1
@End
*/
unsigned int rd,wr;
for(;;) {
- rd = (rdwr>>16) & 0xFFFF;
- wr = rdwr & 0xFFFF;
-
- if ( wr == ((rd + t_size)&0xFFFF) ) { // full
+ rd = (rdwr>>16) & MASK;
+ wr = rdwr & MASK;
+ //printf("write_prepare: rd=%d, wr=%d\n", rd, wr);
- /**
- @Begin
- @Commit_point_define: true
- @Potential_commit_point_label: Prepare_Potential_Point
- @Label: Prepare_Full_Point
- @End
- */
+ if ( wr == ((rd + t_size)&MASK) ) { // full
return NULL;
}
+ /**** Inadmissibility (testcase3.cc, MASK = 1, size = 1) ****/
bool succ = m_rdwr.compare_exchange_weak(rdwr,(rd<<16) |
- ((wr+1)&0xFFFF),mo_acq_rel);
- /**
- @Begin
- @Commit_point_define_check: succ == true
- @Label: Prepare_Succ_Point
- @End
- */
- if (succ)
+ ((wr+1)&MASK),mo_acq_rel);
+ //printf("wr=%d\n", (wr+1)&MASK);
+ if (succ) {
break;
- else
+ } else {
+ /**
+ @Begin
+ @Commit_point_clear: true
+ @Label: PrepareClear1
+ @End
+ */
+
+ /**
+ @Begin
+ @Commit_point_define_check: true
+ @Label: PrepareReadRW2
+ @End
+ */
thrd_yield();
+ }
}
// (*1)
rl::backoff bo;
- while ( (m_read.load(mo_acquire) & 0xFFFF) != rd ) {
- thrd_yield();
+ while (true) {
+ /**** Inadmissibility ****/
+ int read = m_read.load(mo_acquire);
+ if ((read & MASK) != rd)
+ thrd_yield();
+ else
+ break;
}
t_element * p = & ( m_array[ wr % t_size ] );
+ // This is also just a hack to tell the CDSChecker that we have a memory
+ // operation here
+ arr.load(memory_order_relaxed);
+ /**
+ @Begin
+ @Commit_point_clear: true
+ @Label: PrepareClear2
+ @End
+ */
+ /**
+ @Begin
+ @Commit_point_define_check: true
+ @Label: PrepareReadPointer
+ @End
+ */
+
return p;
}
/**
@Begin
@Interface: Publish
- @Commit_point_set: Publish_Point
+ @Commit_point_set: Publish_W_RMW
@ID: (call_id_t) bin
- //@Check:
- //publish_check(__TID__)
- //@Action:
- //publish(__TID__);
+ //@Action: model_print("Publish: %d\n", bin);
@End
*/
void write_publish(t_element *bin)
{
- /**** hb violation ****/
- m_written.fetch_add(1,mo_release);
+ /**** Inadmissibility ****/
+ int tmp = m_written.fetch_add(1,mo_release);
/**
@Begin
@Commit_point_define_check: true
- @Label: Publish_Point
+ @Label: Publish_W_RMW
@End
*/
+ printf("publish: m_written=%d\n", tmp + 1);
}
//-----------------------------------------------------
projects / cdsspec-compiler.git / blobdiff