Commit 053ca488 by Christian Kern

Worked on review comments for ticket #523

parent a023d6e4
......@@ -128,14 +128,20 @@ void embb_internal_thread_index_set_max(unsigned int max) {
*embb_max_number_thread_indices() = max;
}
/**
* \pre the calling thread is the only active thread
*
* \post the thread indices count and calling thread index is reset
*/
void embb_internal_thread_index_reset() {
// This function is only called in tests, usually when all other threads
// except the main thread have terminated. However, the main thread still has
// potentially still stored its old index value in its thread local storage,
// which might be assigned additionally to another thread (as the counter is
// reset), which may lead to hard to detect bugs. Therefore, reset the thread
// local thread id here.
/** This function is only called in tests, usually when all other threads
* except the main thread have terminated. However, the main thread still has
* potentially stored its old index value in its thread local storage,
* which might be assigned additionally to another thread (as the counter is
* reset), which may lead to hard to detect bugs. Therefore, reset the thread
* local thread id here.
*/
embb_internal_thread_index_var = UINT_MAX;
embb_counter_init(embb_thread_index_counter());
}
}
\ No newline at end of file
......@@ -30,7 +30,6 @@
namespace embb {
namespace containers {
namespace internal {
// Visual Studio is complaining, that the return in the last line of this
// function is not reachable. This is true, as long as exceptions are enabled.
// Otherwise, the exception becomes an assertion and with disabling assertions,
......@@ -39,372 +38,354 @@ namespace internal {
#pragma warning(push)
#pragma warning(disable:4702)
#endif
template< typename GuardType >
unsigned int HazardPointer< GuardType >::GetCurrentThreadIndex() {
template< typename GuardType >
unsigned int HazardPointer< GuardType >::GetObjectLocalThreadIndex() {
// first, get the EMBB native thread id.
unsigned int embb_thread_index;
// first, get the EMBB native thread id.
unsigned int embbThreadIndex;
int return_val = embb_internal_thread_index(&embb_thread_index);
int return_val = embb_internal_thread_index(&embbThreadIndex);
if (return_val != EMBB_SUCCESS) {
EMBB_THROW(embb::base::ErrorException, "Could not get thread id");
}
if (return_val != EMBB_SUCCESS) {
EMBB_THROW(embb::base::ErrorException, "Could not get thread id");
}
// iterate over the mappings array
for (unsigned int i = 0; i != max_accessors_count_; ++i) {
// end of mappings? then we need to write our id
if (thread_id_mapping_[i] == -1) {
// try to CAS the initial value with out thread id
int expected = -1;
if (thread_id_mapping_[i].CompareAndSwap(expected,
static_cast<int>(embb_thread_index))) {
//successful, return our mapping
return i;
}
}
// iterate over the mappings array
for (unsigned int i = 0; i != accessorCount; ++i) {
// end of mappings? then we need to write our id
if (threadIdMapping[i] == -1) {
// try to CAS the initial value with out thread id
int expected = -1;
if (threadIdMapping[i].CompareAndSwap(expected,
static_cast<int>(embbThreadIndex))) {
//successful, return our mapping
if (thread_id_mapping_[i] == static_cast<int>(embb_thread_index)) {
// found our mapping!
return i;
}
}
if (threadIdMapping[i] == static_cast<int>(embbThreadIndex)) {
// found our mapping!
return i;
}
}
// when we reach this point, we have too many accessors
// (no mapping possible)
EMBB_THROW(embb::base::ErrorException, "Too many accessors");
// when we reach this point, we have too many accessors
// (no mapping possible)
EMBB_THROW(embb::base::ErrorException, "Too many accessors");
return 0;
}
return 0;
}
#ifdef EMBB_PLATFORM_COMPILER_MSVC
#pragma warning(pop)
#endif
template< typename GuardType >
void HazardPointer< GuardType >::RemoveGuard(int guardPosition){
const unsigned int myThreadId = GetCurrentThreadIndex();
// check invariants...
assert(guardPosition < guardsPerThread && myThreadId < accessorCount);
// set guard
guards[guardPosition*accessorCount + myThreadId] = undefinedGuard;
}
template< typename GuardType >
HazardPointer< GuardType >::HazardPointer(
embb::base::Function<void, GuardType> freeGuardCallback,
GuardType undefinedGuard, int guardsPerThread, int accessors) :
accessorCount(accessors == -1 ?
embb::base::Thread::GetThreadsMaxCount() :
accessors),
undefinedGuard(undefinedGuard),
guardsPerThread(guardsPerThread),
freeGuardCallback(freeGuardCallback) {
threadIdMapping =
static_cast<embb::base::Atomic<int>*>(
embb::base::Allocation::Allocate(sizeof(embb::base::Atomic<int>)
*accessorCount));
for (unsigned int i = 0; i != accessorCount; ++i) {
//in-place new for each cell
new (&threadIdMapping[i]) embb::base::Atomic < int > ;
}
template< typename GuardType >
void HazardPointer< GuardType >::RemoveGuard(int guard_position){
const unsigned int my_thread_id = GetObjectLocalThreadIndex();
guards = static_cast<embb::base::Atomic< GuardType >*>
(embb::base::Allocation::Allocate(
sizeof(embb::base::Atomic< GuardType >) *
guardsPerThread * accessorCount
));
// check invariants...
assert(guard_position < max_guards_per_thread_);
assert(my_thread_id < max_accessors_count_);
for (unsigned int i = 0; i != guardsPerThread * accessorCount; ++i) {
//in-place new for each cell
new (&guards[i]) embb::base::Atomic < GuardType > ;
// set guard
guards_[guard_position*max_accessors_count_ + my_thread_id] =
undefined_guard_;
}
threadLocalRetiredListsTemp = static_cast<GuardType*>
(embb::base::Allocation::Allocate(
sizeof(GuardType) *
guardsPerThread * accessorCount * accessorCount
));
for (unsigned int i = 0; i !=
guardsPerThread * accessorCount * accessorCount; ++i) {
//in-place new for each cell
new (&threadLocalRetiredListsTemp[i]) GuardType;
}
threadLocalRetiredLists = static_cast<GuardType*>
(embb::base::Allocation::Allocate(
sizeof(GuardType) *
guardsPerThread * accessorCount * accessorCount
));
template< typename GuardType >
HazardPointer< GuardType >::HazardPointer(
embb::base::Function<void, GuardType> freeGuardCallback,
GuardType undefined_guard, int guardsPerThread, int accessors) :
max_accessors_count_(accessors < 0 ?
embb::base::Thread::GetThreadsMaxCount() : accessors),
undefined_guard_(undefined_guard),
max_guards_per_thread_(guardsPerThread),
release_object_callback_(freeGuardCallback),
thread_id_mapping_(static_cast<embb::base::Atomic<int>*>(
embb::base::Allocation::Allocate(sizeof(embb::base::Atomic<int>)
*max_accessors_count_))),
guards_(static_cast<embb::base::Atomic< GuardType >*>
(embb::base::Allocation::Allocate(
sizeof(embb::base::Atomic< GuardType >) * max_guards_per_thread_ *
max_accessors_count_))),
thread_local_retired_lists_temp_(static_cast<GuardType*>
(embb::base::Allocation::Allocate(
sizeof(GuardType) * max_guards_per_thread_ * max_accessors_count_ *
max_accessors_count_
))),
thread_local_retired_lists_(static_cast<GuardType*>
(embb::base::Allocation::Allocate(
sizeof(GuardType) * max_guards_per_thread_ * max_accessors_count_ *
max_accessors_count_
))) {
const unsigned int count_guards =
max_guards_per_thread_ * max_accessors_count_;
const unsigned int count_ret_elements =
count_guards * max_accessors_count_;
for (unsigned int i = 0; i != max_accessors_count_; ++i) {
//in-place new for each cell
new (&thread_id_mapping_[i]) embb::base::Atomic < int >(-1);
}
for (unsigned int i = 0; i !=
guardsPerThread * accessorCount * accessorCount; ++i) {
//in-place new for each cell
new (&threadLocalRetiredLists[i]) GuardType;
}
for (unsigned int i = 0; i != count_guards; ++i) {
//in-place new for each cell
new (&guards_[i]) embb::base::Atomic < GuardType >(undefined_guard);
}
// init guards and retired lists to the undefined guard
for (unsigned int i = 0; i != static_cast<unsigned int>(guardsPerThread);
++i) {
for (unsigned int i2 = 0; i2 != accessorCount; ++i2) {
guards[i*accessorCount + i2] = undefinedGuard;
for (unsigned int i = 0; i != count_ret_elements; ++i) {
//in-place new for each cell
new (&thread_local_retired_lists_temp_[i]) GuardType(undefined_guard);
}
}
for (unsigned int j = 0; j != accessorCount; ++j) {
for (unsigned int i = 0; i != guardsPerThread*accessorCount; ++i) {
threadLocalRetiredListsTemp
[j*(accessorCount*guardsPerThread) + i] =
undefinedGuard;
threadLocalRetiredLists
[j*(accessorCount*guardsPerThread) + i] =
undefinedGuard;
for (unsigned int i = 0; i != count_ret_elements; ++i) {
//in-place new for each cell
new (&thread_local_retired_lists_[i]) GuardType(undefined_guard);
}
}
for (unsigned int i = 0; i != accessorCount; ++i) {
//in-place new for each cell
threadIdMapping[i] = -1;
}
}
template< typename GuardType >
HazardPointer< GuardType >::~HazardPointer() {
// Release references from all retired lists. Note that for this to work, the
// data structure using hazard pointer has still to be active... So first, the
// hazard pointer class shall be destructed, then the memory management class
// (e.g. some pool). Otherwise, the hazard pointer class would try to return
// memory to an already destructed memory manager.
for (unsigned int j = 0; j != accessorCount; ++j) {
for (unsigned int i = 0; i != accessorCount*guardsPerThread; ++i) {
template< typename GuardType >
HazardPointer< GuardType >::~HazardPointer() {
const unsigned int count_guards =
max_guards_per_thread_ * max_accessors_count_;
const unsigned int count_ret_elements =
count_guards * max_accessors_count_;
// Release references from all retired lists. Note that for this to work,
// the data structure using hazard pointer has still to be active... So
// first, the hazard pointer class shall be destructed, then the memory
// management class (e.g. some pool). Otherwise, the hazard pointer class
// would try to return memory to an already destructed memory manager.
for (unsigned int i = 0; i != count_ret_elements; ++i) {
GuardType pointerToFree =
threadLocalRetiredLists
[j * accessorCount * guardsPerThread + i];
if (pointerToFree == undefinedGuard) {
thread_local_retired_lists_[i];
if (pointerToFree == undefined_guard_) {
break;
}
freeGuardCallback(pointerToFree);
release_object_callback_(pointerToFree);
}
}
for (unsigned int i = 0; i != accessorCount; ++i) {
threadIdMapping[i].~Atomic();
}
embb::base::Allocation::Free(threadIdMapping);
for (unsigned int i = 0; i != guardsPerThread * accessorCount; ++i) {
guards[i].~Atomic();
}
for (unsigned int i = 0; i != max_accessors_count_; ++i) {
thread_id_mapping_[i].~Atomic();
}
embb::base::Allocation::Free(guards);
embb::base::Allocation::Free(thread_id_mapping_);
for (unsigned int i = 0; i !=
guardsPerThread * accessorCount * accessorCount; ++i) {
threadLocalRetiredListsTemp[i].~GuardType();
}
embb::base::Allocation::Free(threadLocalRetiredListsTemp);
for (unsigned int i = 0; i != count_guards; ++i) {
guards_[i].~Atomic();
}
for (unsigned int i = 0; i !=
guardsPerThread * accessorCount * accessorCount; ++i) {
threadLocalRetiredLists[i].~GuardType();
}
embb::base::Allocation::Free(guards_);
embb::base::Allocation::Free(threadLocalRetiredLists);
}
for (unsigned int i = 0; i != count_ret_elements; ++i) {
thread_local_retired_lists_temp_[i].~GuardType();
}
template< typename GuardType >
void HazardPointer< GuardType >::Guard(int guardPosition,
GuardType guardedElement) {
const unsigned int myThreadId = GetCurrentThreadIndex();
embb::base::Allocation::Free(thread_local_retired_lists_temp_);
// check invariants...
assert(guardPosition < guardsPerThread && myThreadId < accessorCount);
for (unsigned int i = 0; i != count_ret_elements; ++i) {
thread_local_retired_lists_[i].~GuardType();
}
// set guard
guards[guardPosition*accessorCount + myThreadId] = guardedElement;
}
embb::base::Allocation::Free(thread_local_retired_lists_);
}
template< typename GuardType >
size_t HazardPointer< GuardType >::ComputeMaximumRetiredObjectCount(
size_t guardsPerThread, int accessors) {
template< typename GuardType >
void HazardPointer< GuardType >::Guard(int guardPosition,
GuardType guardedElement) {
const unsigned int my_thread_id = GetObjectLocalThreadIndex();
unsigned int accessorCount = (accessors == -1 ?
embb::base::Thread::GetThreadsMaxCount() :
accessors);
// check invariants...
assert(guardPosition < max_guards_per_thread_);
assert(my_thread_id < max_accessors_count_);
return static_cast<size_t>(
guardsPerThread * accessorCount * accessorCount);
}
// set guard
guards_[guardPosition*max_accessors_count_ + my_thread_id] = guardedElement;
}
template< typename GuardType >
void HazardPointer< GuardType >::CopyRetiredList(GuardType* sourceList,
GuardType* targetList, unsigned int retiredListSize,
GuardType undefinedGuard) {
bool done = false;
for (unsigned int ii = 0; ii != retiredListSize; ++ii) {
if (!done) {
GuardType guardToCopy = sourceList[ii];
template< typename GuardType >
size_t HazardPointer< GuardType >::ComputeMaximumRetiredObjectCount(
size_t guardsPerThread, int accessors) {
unsigned int accessorCount = (accessors == -1 ?
embb::base::Thread::GetThreadsMaxCount() :
accessors);
if (guardToCopy == undefinedGuard) {
done = true;
return static_cast<size_t>(
guardsPerThread * accessorCount * accessorCount);
}
/**
* Remark: it might be faster to just swap pointers for temp retired list and
* retired list. However, with the current implementation (one array for all
* retired and retired temp lists, respectively) this is not possible. This is
* not changed until this copying accounts for a performance problem. The
* copying is not the bottleneck currently.
*/
template< typename GuardType >
void HazardPointer< GuardType >::CopyRetiredList(GuardType* sourceList,
GuardType* targetList, unsigned int retiredListSize,
GuardType undefinedGuard) {
bool done = false;
for (unsigned int ii = 0; ii != retiredListSize; ++ii) {
if (!done) {
GuardType guardToCopy = sourceList[ii];
if (guardToCopy == undefinedGuard) {
done = true;
if (targetList[ii] == undefinedGuard) {
// end of target list
break;
}
}
targetList[ii] = guardToCopy;
}
else {
// we copied the whole source list, remaining values in the target
// have to be zeroed.
if (targetList[ii] == undefinedGuard) {
// end of target list
break;
}
else {
targetList[ii] = undefinedGuard;
}
}
targetList[ii] = guardToCopy;
}
else {
// we copied the whole source list, remaining values in the target
// have to be zeroed.
if (targetList[ii] == undefinedGuard) {
// end of target list
}
template< typename GuardType >
void HazardPointer< GuardType >::UpdateRetiredList(GuardType* retired_list,
GuardType* updated_retired_list, unsigned int retired_list_size,
GuardType guarded_element, GuardType considered_hazard,
GuardType undefined_guard) {
// no hazard set here
if (considered_hazard == undefined_guard)
return;
// if this hazard is currently in the union of
// threadLocalRetiredLists and pointerToRetire, but not yet in
// threadLocalRetiredListsTemp, add it to that list
bool contained_in_union = false;
// first iterate over our retired list
for (unsigned int i = 0; i != retired_list_size; ++i) {
// when reaching 0, we can stop iterating (end of the "list")
if (retired_list[i] == 0)
break;
// the hazard is contained in the retired list... it shall go
// into the temp list, if not already there
if (retired_list[i] == considered_hazard) {
contained_in_union = true;
break;
}
else {
targetList[ii] = undefinedGuard;
}
}
}
}
template< typename GuardType >
void HazardPointer< GuardType >::UpdateRetiredList(GuardType* retiredList,
GuardType* updatedRetiredList, unsigned int retiredListSize,
GuardType guardedElement, GuardType consideredHazard,
GuardType undefinedGuard) {
// no hazard set here
if (consideredHazard == undefinedGuard)
return;
// if this hazard is currently in the union of
// threadLocalRetiredLists and pointerToRetire, but not yet in
// threadLocalRetiredListsTemp, add it to that list
bool containedInUnion = false;
// first iterate over our retired list
for (unsigned int ii = 0; ii != retiredListSize; ++ii) {
// when reaching 0, we can stop iterating (end of the "list")
if (retiredList[ii] == 0)
break;
// the hazard is contained in the retired list... it shall go
// into the temp list, if not already there
if (retiredList[ii] == consideredHazard) {
containedInUnion = true;
break;
// the union also contains pointerToRetire
if (!contained_in_union) {
contained_in_union = (considered_hazard == guarded_element);
}
}
// the union also contains pointerToRetire
if (!containedInUnion) {
containedInUnion = (consideredHazard == guardedElement);
}
// add the pointer to temp. retired list, if not already there
if (contained_in_union) {
for (unsigned int ii = 0; ii != retired_list_size; ++ii) {
// is it already there?
if (updated_retired_list[ii] == considered_hazard)
break;
// add the pointer to temp. retired list, if not already there
if (containedInUnion) {
for (unsigned int iii = 0; iii != retiredListSize; ++iii) {
// end of the list
if (updated_retired_list[ii] == undefined_guard) {
// add hazard
updated_retired_list[ii] = considered_hazard;
// is it already there?
if (updatedRetiredList[iii] == consideredHazard)
// we are done here...
break;
// end of the list
if (updatedRetiredList[iii] == undefinedGuard) {
// add hazard
updatedRetiredList[iii] = consideredHazard;
// we are done here...
break;
}
}
}
}
}
template< typename GuardType >
void HazardPointer< GuardType >::EnqueueForDeletion(GuardType toRetire) {
template< typename GuardType >
void HazardPointer< GuardType >::EnqueueForDeletion(GuardType toRetire) {
unsigned int my_thread_id = GetObjectLocalThreadIndex();
unsigned int myThreadId = GetCurrentThreadIndex();
// check for invariant
assert(my_thread_id < max_accessors_count_);
// check for invariant
assert(myThreadId < accessorCount);
const unsigned int retired_list_size = max_accessors_count_ *
max_guards_per_thread_;
unsigned int retiredListSize = accessorCount * guardsPerThread;
const unsigned int count_guards = max_accessors_count_ *
max_guards_per_thread_;
GuardType* retiredList =
&threadLocalRetiredLists[myThreadId * retiredListSize];
GuardType* retired_list =
&thread_local_retired_lists_[my_thread_id * retired_list_size];
GuardType* retiredListTemp =
&threadLocalRetiredListsTemp[myThreadId * retiredListSize];
GuardType* retired_list_temp =
&thread_local_retired_lists_temp_[my_thread_id * retired_list_size];
// wipe my temp. retired list...
for (unsigned int i = 0; i < retiredListSize; ++i) {
// the list is filled always from left to right, so occurring the first
// undefinedGuard, the remaining ones are also undefinedGuard...
if (retiredListTemp[i] == undefinedGuard)
break;
// wipe my temp. retired list...
for (unsigned int i = 0; i < retired_list_size; ++i) {
// the list is filled always from left to right, so occurring the first
// undefinedGuard, the remaining ones are also undefinedGuard...
if (retired_list_temp[i] == undefined_guard_)
break;
retiredListTemp[i] = undefinedGuard;
}
retired_list_temp[i] = undefined_guard_;
}
// we test each hazard if it is in the union of retiredList and
// guardedElement. If it is, it goes into the new retired list...
for (unsigned int i = 0; i != accessorCount*guardsPerThread; ++i) {
// consider each current active guard
GuardType consideredHazard = guards[i].Load();
UpdateRetiredList(retiredList, retiredListTemp, retiredListSize,
toRetire, consideredHazard, undefinedGuard);
}
// we test each hazard if it is in the union of retiredList and
// guardedElement. If it is, it goes into the new retired list...
for (unsigned int i = 0; i != count_guards; ++i) {
// consider each current active guard
GuardType considered_hazard = guards_[i].Load();
UpdateRetiredList(retired_list, retired_list_temp, retired_list_size,
toRetire, considered_hazard, undefined_guard_);
}
// now we created a a new retired list... the elements that are "removed" from
// the old retired list can be safely deleted now...
for (int ii = -1; ii != static_cast<int>(retiredListSize); ++ii) {
// we iterate over the current retired list... -1 is used as dummy element
// in the iteration, to also iterate over the pointerToRetire, which is
// logically also part of the current retired list...
int retired_list_size_signed = static_cast<int>(retired_list_size);
assert(retired_list_size_signed >= 0);
// end of the list, stop iterating
if (ii >= 0 && retiredList[ii] == undefinedGuard)
break;
// now we created a a new retired list... the elements that are "removed"
// from the old retired list can be safely deleted now...
for (int i = -1; i != retired_list_size_signed; ++i) {
// we iterate over the current retired list... -1 is used as dummy element
// in the iteration, to also iterate over the pointerToRetire, which is
// logically also part of the current retired list...
GuardType toCheckIfInNewList = undefinedGuard;
// end of the list, stop iterating
if (i >= 0 && retired_list[i] == undefined_guard_)
break;
toCheckIfInNewList = (ii == -1 ? toRetire : retiredList[ii]);
GuardType to_check_if_in_new_list = undefined_guard_;
// still in the new retired list?
bool stillInList = false;
for (unsigned int iii = 0; iii != retiredListSize; ++iii) {
// end of list
if (retiredListTemp[iii] == undefinedGuard)
to_check_if_in_new_list = (i == -1 ? toRetire : retired_list[i]);
// still in the new retired list?
bool still_in_list = false;
for (unsigned int ii = 0; ii != retired_list_size; ++ii) {
// end of list
if (retired_list_temp[ii] == undefined_guard_)
break;
if (to_check_if_in_new_list == retired_list_temp[ii]) {
// still in list, cannot delete element!
still_in_list = true;
break;
}
}
if (toCheckIfInNewList == retiredListTemp[iii]) {
// still in list, cannot delete!
stillInList = true;
break;
if (!still_in_list) {
this->release_object_callback_(to_check_if_in_new_list);
}
}
if (!stillInList) {
this->freeGuardCallback(toCheckIfInNewList);
}
// copy the updated retired list (temp) to the retired list...
CopyRetiredList(retired_list_temp, retired_list, retired_list_size,
undefined_guard_);
}
// copy the updated retired list (temp) to the retired list...
CopyRetiredList(retiredListTemp, retiredList, retiredListSize,
undefinedGuard);
}
} // namespace internal
} // namespace containers
} // namespace embb
......
......@@ -53,7 +53,6 @@ class HazardPointerTest2;
namespace embb {
namespace containers {
namespace internal {
/**
* This class contains a hazard pointer implementation following publication:
*
......@@ -61,7 +60,7 @@ namespace internal {
* objects." IEEE Transactions on Parallel and Distributed Systems, 15.6 (2004)
* : 491-504.
*
* Hazard pointer are a wait-free memory reclamation scheme for lock-free
* Hazard pointers are a wait-free memory reclamation scheme for lock-free
* algorithms. Loosely speaking, they act as garbage collector. The release of
* objects contained within the memory, managed by the hazard pointer class, is
* intercepted and possibly delayed to avoid concurrency bugs.
......@@ -107,111 +106,13 @@ namespace internal {
* when objects shall be freed. In this implementation, we free whenever it is
* possibly to do so, as we want to keep the memory footprint as low as
* possible. We also don't see a performance drop in the current algorithms that
* are using hazard pointer, when not using a threshold.
* are using hazard pointers, when not using a threshold.
*
* \tparam GuardType the type of the guards. Usually the pointer type of some
* object to protect.
*/
template< typename GuardType >
class HazardPointer {
private:
/**
* HazardPointerTest2 is a white-box test, needing access to private members
* of this class. So declaring it as friend.
*/
friend class embb::containers::test::HazardPointerTest2;
/**
* The hazard pointer guards, represented as array. Each thread has a fixed
* set of slots (guardsPerThread) within this array.
*/
embb::base::Atomic<GuardType>* guards;
/**
* \see threadLocalRetiredLists documentation
*/
GuardType* threadLocalRetiredListsTemp;
/**
* A lists of lists, represented as single array. Each thread maintains a
* list of retired pointers, that are objects that are logically released
* but not released because some thread placed a guard on it.
*/
GuardType* threadLocalRetiredLists;
/**
* This number determines the amount of maximal accessors (threads) that
* will access this hazard pointer instance. Note that a thread once
* accessing this object will be permanently count as accessor, even if not
* participating anymore. If too many threads access this object, an
* assertion is thrown.
*/
unsigned int accessorCount;
/**
* The guard value denoting "not guarded"
*/
GuardType undefinedGuard;
/**
* The count of guards that can be set per thread.
*/
int guardsPerThread;
/**
* The functor that is called to release an object. This is called by this
* class, when it is safe to do so, i.e., no thread accesses this object
* anymore.
*/
embb::base::Function<void, GuardType> freeGuardCallback;
/**
* Mapping from EMBB thread id to internal thread ids Internal thread ids
* are in range [0;accesor_count-1]. The position of a EMBB thread id in
* that array determines the respective internal thread id.
*/
embb::base::Atomic<int>* threadIdMapping;
/**
* Each thread is assigned a thread index (starting with 0). Get the index of
* the current thread. Note that this is not the global index, but an internal
* one. The user is free to define less accessors than the amount of default
* threads. This is useful, as the number of accessors accounts quadratic for
* the memory consumption, so the user should have the possibility to avoid
* memory wastage, when only having a small, fixed size, number of accessors.
*
* @return current thread index
*/
unsigned int GetCurrentThreadIndex();
/**
* Copy retired list \c sourceList to retired list \c targetList
*/
static void CopyRetiredList(GuardType* sourceList,
/**<[IN] the source retired list*/
GuardType* targetList,
/**<[IN] the target retired list*/
unsigned int singleRetiredListSize,
/**<[IN] the size of a thread local retired list*/
GuardType undefinedGuard
/**<[IN] the undefined guard (usually the NULL pointer)*/
);
static void UpdateRetiredList(
GuardType* retiredList,
/**<[IN] the old retired list*/
GuardType* updatedRetiredList,
/**<[IN] the updated retired list*/
unsigned int retiredListSize,
/**<[IN] the size of a thread local retired list*/
GuardType toRetire,
/**<[IN] the element to retire*/
GuardType consideredHazard,
/**<[IN] the currently considered hazard*/
GuardType undefinedGuard
/**<[IN] the undefined guard (usually the NULL pointer)*/
);
public:
/**
......@@ -221,7 +122,7 @@ class HazardPointer {
* guarantee at each point in time. More specific, on top of the guaranteed
* count of objects, he has to provide the additional count of objects that
* can be (worst-case) contained in the retired lists and therefore are not
* released yet. The size of all retired lists is guardsPerThread *
* released yet. The size sum of all retired lists is guardsPerThread *
* accessorCount * accessorCount, which is computed using this function. So
* the result of function denotes to the user, how many objects he has to
* allocate additionally to the guaranteed count.
......@@ -232,10 +133,10 @@ class HazardPointer {
size_t guardsPerThread,
/**<[IN] the count of guards per thread*/
int accessors = -1
/**<[IN] Number of accessors. Determines, how many threads will access
the hazard pointer object. Default value -1 will allow the
maximum amount of threads as defined with
\c embb::base::Thread::GetThreadsMaxCount()*/
/**<[IN] Number of accessors. Determines, how many threads will access
the hazard pointer object. Default value -1 will allow the
maximum amount of threads as defined with
\c embb::base::Thread::GetThreadsMaxCount()*/
);
/**
......@@ -245,9 +146,9 @@ class HazardPointer {
*
* \memory We dynamically allocate the following:
*
* (sizeof(Atomic<int>) * accessorCount) + (sizeof(Atomic<GuardType>) *
* guards_per_thread * accessorCount) + (2*sizeof(GuardType) *
* guards_per_thread * accessorCount^2)
* (sizeof(Atomic<int>) * accessors) + (sizeof(Atomic<GuardType>) *
* guards_per_thread * accessors) + (2*sizeof(GuardType) *
* guards_per_thread * accessors^2)
*
* The last addend is the dominant one, as accessorCount accounts
* quadratically for it.
......@@ -277,29 +178,137 @@ class HazardPointer {
~HazardPointer();
/**
* Guards \c toGuard. If the guardedElement is passed to \c EnqueueForDeletion
* Guards \c to_guard. If the guarded_element is passed to \c EnqueueForDeletion
* it is prevented from release from now on. The user must have a check, that
* EnqueueForDeletion has not been called on toGuard, before the guarding took
* EnqueueForDeletion has not been called on to_guard, before the guarding took
* effect.
*
* \waitfree
*/
void Guard(int guardPosition, GuardType toGuard);
void Guard(
int guard_position,
/**<[IN] position to place guard*/
GuardType to_guard
/**<[IN] element to guard*/
);
/**
* Enqueue a pointer for deletion. If not guarded, it is deleted immediately.
* If it is guarded, it is added to a thread local retired list, and deleted
* in a subsequent call to \c EnqueueForDeletion, when no guard is placed on
* it anymore.
* Enqueue guarded element for deletion. If not guarded, it is deleted
* immediately. If it is guarded, it is added to a thread local retired list,
* and deleted in a subsequent call to \c EnqueueForDeletion, when no guard is
* placed on it anymore.
*/
void EnqueueForDeletion(GuardType guardedElement);
void EnqueueForDeletion(
GuardType guarded_element
/**<[IN] element to logically delete*/
);
/**
* Explicitly remove guard from thread local slot.
*
* \waitfree
*/
void RemoveGuard(int guardPosition);
void RemoveGuard(int guard_position);
private:
/**
* HazardPointerTest2 is a white-box test, needing access to private members
* of this class. So declaring it as friend.
*/
friend class embb::containers::test::HazardPointerTest2;
/**
* This number determines the amount of maximal accessors (threads) that
* will access this hazard pointer instance. Note that a thread once
* accessing this object will be permanently count as accessor, even if not
* participating anymore. If too many threads access this object, an
* exception is thrown.
*/
unsigned int max_accessors_count_;
/**
* The guard value denoting "not guarded"
*/
GuardType undefined_guard_;
/**
* The maximal count of guards that can be set per thread.
*/
int max_guards_per_thread_;
/**
* The functor that is called to release an object. This is called by this
* class, when it is safe to do so, i.e., no thread accesses this object
* anymore.
*/
embb::base::Function<void, GuardType> release_object_callback_;
/**
* Mapping from EMBB thread id to hazard pointer thread ids. Hazard pointer
* thread ids are in range [0;accesor_count-1]. The position of a EMBB thread
* id in that array determines the respective hazard pointer thread id.
*/
embb::base::Atomic<int>* thread_id_mapping_;
/**
* The hazard pointer guards, represented as array. Each thread has a fixed
* set of slots (guardsPerThread) within this array.
*/
embb::base::Atomic<GuardType>* guards_;
/**
* \see threadLocalRetiredLists documentation
*/
GuardType* thread_local_retired_lists_temp_;
/**
* A list of lists, represented as single array. Each thread maintains a list
* of retired pointers, that are objects that are logically released but not
* released because some thread placed a guard on it.
*/
GuardType* thread_local_retired_lists_;
/**
* Each thread is assigned a thread index (starting with 0). Get the index of
* the current thread. Note that this is not the global index, but an hazard
* pointer class internal one. The user is free to define less accessors than
* the amount of default threads. This is useful, as the number of accessors
* accounts quadratic for the memory consumption, so the user should have the
* possibility to avoid memory wastage when only having a small, fixed size,
* number of accessors.
*
* @return current (hazard pointer object local) thread index
*/
unsigned int GetObjectLocalThreadIndex();
/**
* Copy retired list \c sourceList to retired list \c targetList
*/
static void CopyRetiredList(
GuardType* source_list,
/**<[IN] the source retired list*/
GuardType* target_list,
/**<[IN] the target retired list*/
unsigned int single_retired_list_size,
/**<[IN] the size of a thread local retired list*/
GuardType undefined_guard
/**<[IN] the undefined guard (usually the NULL pointer)*/
);
static void UpdateRetiredList(
GuardType* retired_list,
/**<[IN] the old retired list*/
GuardType* updated_retired_list,
/**<[IN] the updated retired list*/
unsigned int retired_list_size,
/**<[IN] the size of a thread local retired list*/
GuardType to_retire,
/**<[IN] the element to retire*/
GuardType considered_hazard,
/**<[IN] the currently considered hazard*/
GuardType undefined_guard
/**<[IN] the undefined guard (usually the NULL pointer)*/
);
};
} // namespace internal
} // namespace containers
......
......@@ -31,23 +31,22 @@
namespace embb {
namespace containers {
namespace test {
IntObjectTestPool::IntObjectTestPool(unsigned int poolSize) :
poolSize(poolSize)
IntObjectTestPool::IntObjectTestPool(unsigned int pool_size) :
poolSize(pool_size)
{
simplePoolObjects = static_cast<int*>(
embb::base::Allocation::Allocate(sizeof(int)*poolSize));
embb::base::Allocation::Allocate(sizeof(int)*pool_size));
simplePool = static_cast<embb::base::Atomic<int>*> (
embb::base::Allocation::Allocate(sizeof(embb::base::Atomic<int>)*
poolSize));
pool_size));
for (unsigned int i = 0; i != poolSize; ++i) {
for (unsigned int i = 0; i != pool_size; ++i) {
//in-place new for each array cell
new (&simplePool[i]) embb::base::Atomic<int>;
}
for (unsigned int i = 0; i != poolSize; ++i) {
for (unsigned int i = 0; i != pool_size; ++i) {
simplePool[i] = FREE_MARKER;
simplePoolObjects[i] = 0;
}
......@@ -75,8 +74,8 @@ int* IntObjectTestPool::Allocate() {
return 0;
}
void IntObjectTestPool::Release(int* objectPointer) {
int cell = objectPointer - simplePoolObjects;
void IntObjectTestPool::Release(int* object_pointer) {
int cell = object_pointer - simplePoolObjects;
simplePool[cell].Store(FREE_MARKER);
}
......@@ -85,17 +84,17 @@ HazardPointerTest::HazardPointerTest() :
#pragma warning(push)
#pragma warning(disable:4355)
#endif
deletePointerCallback(*this, &HazardPointerTest::DeletePointerCallback),
delete_pointer_callback_(*this, &HazardPointerTest::DeletePointerCallback),
#ifdef EMBB_PLATFORM_COMPILER_MSVC
#pragma warning(pop)
#endif
objectPool(NULL),
stack(NULL),
hazardPointer(NULL),
nThreads(static_cast<int>
object_pool_(NULL),
stack_(NULL),
hazard_pointer_(NULL),
n_threads_(static_cast<int>
(partest::TestSuite::GetDefaultNumThreads())) {
nElementsPerThread = 100;
nElements = nThreads*nElementsPerThread;
n_elements_per_thread_ = 100;
n_elements_ = n_threads_*n_elements_per_thread_;
embb::base::Function < void, embb::base::Atomic<int>* >
deletePointerCallback(
*this,
......@@ -111,45 +110,45 @@ deletePointerCallback(*this, &HazardPointerTest::DeletePointerCallback),
Pre(&HazardPointerTest::HazardPointerTest1Pre, this).
Add(
&HazardPointerTest::HazardPointerTest1ThreadMethod,
this, static_cast<size_t>(nThreads)).
this, static_cast<size_t>(n_threads_)).
Post(&HazardPointerTest::HazardPointerTest1Post, this);
}
void HazardPointerTest::HazardPointerTest1Pre() {
embb_internal_thread_index_reset();
objectPool =
object_pool_ =
embb::base::Allocation::
New<embb::containers::ObjectPool< embb::base::Atomic<int> > >
(static_cast<size_t>(nElements));
(static_cast<size_t>(n_elements_));
stack = embb::base::Allocation::
stack_ = embb::base::Allocation::
New<embb::containers::LockFreeStack< embb::base::Atomic<int>* > >
(static_cast<size_t>(nElements));
(static_cast<size_t>(n_elements_));
hazardPointer = embb::base::Allocation::
hazard_pointer_ = embb::base::Allocation::
New<embb::containers::internal::HazardPointer < embb::base::Atomic<int>* > >
(deletePointerCallback,
(delete_pointer_callback_,
static_cast<embb::base::Atomic<int>*>(NULL),
1);
}
void HazardPointerTest::HazardPointerTest1Post() {
embb::base::Allocation::Delete(hazardPointer);
embb::base::Allocation::Delete(objectPool);
embb::base::Allocation::Delete(stack);
embb::base::Allocation::Delete(hazard_pointer_);
embb::base::Allocation::Delete(object_pool_);
embb::base::Allocation::Delete(stack_);
}
void HazardPointerTest::HazardPointerTest1ThreadMethod() {
unsigned int thread_index;
embb_internal_thread_index(&thread_index);
for (int i = 0; i != nElementsPerThread; ++i) {
embb::base::Atomic<int>* allocated_object = objectPool->Allocate(0);
for (int i = 0; i != n_elements_per_thread_; ++i) {
embb::base::Atomic<int>* allocated_object = object_pool_->Allocate(0);
hazardPointer->Guard(0, allocated_object);
hazard_pointer_->Guard(0, allocated_object);
bool success = stack->TryPush(allocated_object);
bool success = stack_->TryPush(allocated_object);
PT_ASSERT(success == true);
......@@ -161,7 +160,7 @@ void HazardPointerTest::HazardPointerTest1ThreadMethod() {
bool success_pop;
while (
(success_pop = stack->TryPop(allocated_object_from_different_thread))
(success_pop = stack_->TryPop(allocated_object_from_different_thread))
== true
&& allocated_object_from_different_thread == allocated_object
) {
......@@ -171,99 +170,100 @@ void HazardPointerTest::HazardPointerTest1ThreadMethod() {
same = true;
break;
}
bool success = stack->TryPush(allocated_object_from_different_thread);
bool success = stack_->TryPush(allocated_object_from_different_thread);
PT_ASSERT(success == true);
}
PT_ASSERT(success_pop == true);
allocated_object->Store(1);
hazardPointer->EnqueueForDeletion(allocated_object);
hazard_pointer_->EnqueueForDeletion(allocated_object);
if (!same) {
hazardPointer->Guard(0, allocated_object_from_different_thread);
hazard_pointer_->Guard(0, allocated_object_from_different_thread);
// if this holds, we were successful in guarding... otherwise we
// were to late, because the pointer has already been added
// to the retired list.
if (*allocated_object_from_different_thread == 0) {
// the pointer must not be deleted here!
vectorMutex.Lock();
vector_mutex_.Lock();
for (std::vector< embb::base::Atomic<int>* >::iterator
it = deletedVector.begin();
it != deletedVector.end();
it = deleted_vector_.begin();
it != deleted_vector_.end();
++it) {
PT_ASSERT(*it != allocated_object_from_different_thread);
}
vectorMutex.Unlock();
vector_mutex_.Unlock();
}
hazardPointer->Guard(0, NULL);
hazard_pointer_->Guard(0, NULL);
}
}
}
void HazardPointerTest::DeletePointerCallback
(embb::base::Atomic<int>* to_delete) {
vectorMutex.Lock();
deletedVector.push_back(to_delete);
vectorMutex.Unlock();
vector_mutex_.Lock();
deleted_vector_.push_back(to_delete);
vector_mutex_.Unlock();
}
void HazardPointerTest2::DeletePointerCallback(int* toDelete) {
testPool->Release(toDelete);
void HazardPointerTest2::DeletePointerCallback(int* to_delete) {
test_pool_->Release(to_delete);
}
bool HazardPointerTest2::SetRelativeGuards() {
unsigned int threadIndex;
embb_internal_thread_index(&threadIndex);
unsigned int thread_index;
embb_internal_thread_index(&thread_index);
unsigned int my_begin = guardsPerThreadCount*threadIndex;
int guardNumber = 0;
unsigned int my_begin = guards_per_phread_count_*thread_index;
int guard_number = 0;
unsigned int alreadyGuarded = 0;
for (unsigned int i = my_begin; i != my_begin + guardsPerThreadCount; ++i){
if (sharedGuarded[i] != 0) {
for (unsigned int i = my_begin; i != my_begin + guards_per_phread_count_;
++i){
if (shared_guarded_[i] != 0) {
alreadyGuarded++;
guardNumber++;
guard_number++;
continue;
}
int * toGuard = sharedAllocated[i];
if (toGuard) {
hazardPointer->Guard(guardNumber, toGuard);
int * to_guard = shared_allocated_[i];
if (to_guard) {
hazard_pointer_->Guard(guard_number, to_guard);
// changed in the meantime?
if (toGuard == sharedAllocated[i].Load()) {
if (to_guard == shared_allocated_[i].Load()) {
// guard was successful. Communicate to other threads.
sharedGuarded[i] = toGuard;
shared_guarded_[i] = to_guard;
}
else {
// reset the guard, couldn't guard...
hazardPointer->RemoveGuard(guardNumber);
hazard_pointer_->RemoveGuard(guard_number);
}
}
guardNumber++;
guard_number++;
}
return(alreadyGuarded == guardsPerThreadCount);
return(alreadyGuarded == guards_per_phread_count_);
}
void HazardPointerTest2::HazardPointerTest2Master() {
// while the hazard pointer guard array is not full
int** allocatedLocal = static_cast<int**>(
embb::base::Allocation::Allocate(sizeof(int*)*guaranteedCapacityPool));
embb::base::Allocation::Allocate(sizeof(int*)*guaranteed_capacity_pool_));
bool full = false;
while (!full) {
full = true;
for (unsigned int i = 0; i != guaranteedCapacityPool; ++i) {
if (sharedGuarded[i] == 0) {
for (unsigned int i = 0; i != guaranteed_capacity_pool_; ++i) {
if (shared_guarded_[i] == 0) {
full = false;
break;
}
}
// not all guards set
for (unsigned int i = 0; i != guaranteedCapacityPool; ++i) {
allocatedLocal[i] = testPool->Allocate();
sharedAllocated[i].Store(allocatedLocal[i]);
for (unsigned int i = 0; i != guaranteed_capacity_pool_; ++i) {
allocatedLocal[i] = test_pool_->Allocate();
shared_allocated_[i].Store(allocatedLocal[i]);
}
// set my hazards. We do not have to check, this must be successful
......@@ -271,9 +271,9 @@ void HazardPointerTest2::HazardPointerTest2Master() {
SetRelativeGuards();
// free
for (unsigned int i = 0; i != guaranteedCapacityPool; ++i) {
sharedAllocated[i].Store(0);
hazardPointer->EnqueueForDeletion(allocatedLocal[i]);
for (unsigned int i = 0; i != guaranteed_capacity_pool_; ++i) {
shared_allocated_[i].Store(0);
hazard_pointer_->EnqueueForDeletion(allocatedLocal[i]);
}
}
......@@ -289,54 +289,54 @@ void HazardPointerTest2::HazardPointerTest2Slave() {
void HazardPointerTest2::HazardPointerTest2Pre() {
embb_internal_thread_index_reset();
currentMaster = 0;
sync1 = 0;
sync2 = 0;
current_master_ = 0;
sync1_ = 0;
sync2_ = 0;
// first the test pool has to be created
testPool = embb::base::Allocation::New<IntObjectTestPool>(poolSizeUsingHazardPointer);
test_pool_ = embb::base::Allocation::New<IntObjectTestPool>
(pool_size_using_hazard_pointer_);
// after the pool has been created, we create the hp class
hazardPointer = embb::base::Allocation::New <
hazard_pointer_ = embb::base::Allocation::New <
embb::containers::internal::HazardPointer<int*> >
(deletePointerCallback, static_cast<int*>(NULL),
static_cast<int>(guardsPerThreadCount), nThreads);
(delete_pointer_callback_, static_cast<int*>(NULL),
static_cast<int>(guards_per_phread_count_), n_threads);
sharedGuarded = static_cast<embb::base::Atomic<int*>*>(
shared_guarded_ = static_cast<embb::base::Atomic<int*>*>(
embb::base::Allocation::Allocate(sizeof(embb::base::Atomic<int*>)*
guaranteedCapacityPool)
guaranteed_capacity_pool_)
);
for (unsigned int i = 0; i !=
guaranteedCapacityPool; ++i) {
guaranteed_capacity_pool_; ++i) {
//in-place new for each array cell
new (&sharedGuarded[i]) embb::base::Atomic < int* > ;
new (&shared_guarded_[i]) embb::base::Atomic < int* > ;
}
sharedAllocated = static_cast<embb::base::Atomic<int*>*>(
shared_allocated_ = static_cast<embb::base::Atomic<int*>*>(
embb::base::Allocation::Allocate(sizeof(embb::base::Atomic<int*>)*
guaranteedCapacityPool)
guaranteed_capacity_pool_)
);
for (unsigned int i = 0; i !=
guaranteedCapacityPool; ++i) {
guaranteed_capacity_pool_; ++i) {
//in-place new for each array cell
new (&sharedAllocated[i]) embb::base::Atomic < int* > ;
new (&shared_allocated_[i]) embb::base::Atomic < int* > ;
}
for (unsigned int i = 0; i != guaranteedCapacityPool; ++i) {
sharedGuarded[i] = 0;
sharedAllocated[i] = 0;
for (unsigned int i = 0; i != guaranteed_capacity_pool_; ++i) {
shared_guarded_[i] = 0;
shared_allocated_[i] = 0;
}
}
void HazardPointerTest2::HazardPointerTest2Post() {
for (unsigned int i = 0; i != static_cast<unsigned int>(nThreads); ++i) {
for (unsigned int i2 = 0; i2 != static_cast<unsigned int>(nThreads)*
guardsPerThreadCount; ++i2) {
if (hazardPointer->threadLocalRetiredLists
[i2 + i*nThreads*guardsPerThreadCount] == NULL) {
for (unsigned int i = 0; i != static_cast<unsigned int>(n_threads); ++i) {
for (unsigned int i2 = 0; i2 != static_cast<unsigned int>(n_threads)*
guards_per_phread_count_; ++i2) {
if (hazard_pointer_->thread_local_retired_lists_
[i2 + i*n_threads*guards_per_phread_count_] == NULL) {
// all retired lists must be completely filled
PT_ASSERT(false);
}
......@@ -344,21 +344,21 @@ void HazardPointerTest2::HazardPointerTest2Post() {
}
unsigned int checks = 0;
for (unsigned int i = 0; i != static_cast<unsigned int>(nThreads); ++i) {
for (unsigned int i2 = 0; i2 != static_cast<unsigned int>(nThreads)*
guardsPerThreadCount; ++i2) {
for (unsigned int j = 0; j != static_cast<unsigned int>(nThreads); ++j) {
for (unsigned int j2 = 0; j2 != static_cast<unsigned int>(nThreads)*
guardsPerThreadCount; ++j2) {
for (unsigned int i = 0; i != static_cast<unsigned int>(n_threads); ++i) {
for (unsigned int i2 = 0; i2 != static_cast<unsigned int>(n_threads)*
guards_per_phread_count_; ++i2) {
for (unsigned int j = 0; j != static_cast<unsigned int>(n_threads); ++j) {
for (unsigned int j2 = 0; j2 != static_cast<unsigned int>(n_threads)*
guards_per_phread_count_; ++j2) {
if (i2 == j2 && i == j)
continue;
// all retired elements have to be disjoint
PT_ASSERT(
hazardPointer->threadLocalRetiredLists
[i2 + i*nThreads*guardsPerThreadCount] !=
hazardPointer->threadLocalRetiredLists
[j2 + j*nThreads*guardsPerThreadCount]
hazard_pointer_->thread_local_retired_lists_
[i2 + i*n_threads*guards_per_phread_count_] !=
hazard_pointer_->thread_local_retired_lists_
[j2 + j*n_threads*guards_per_phread_count_]
);
checks++;
......@@ -370,16 +370,16 @@ void HazardPointerTest2::HazardPointerTest2Post() {
// sanity check on the count of expected comparisons.
PT_ASSERT(
checks ==
nThreads*nThreads*guardsPerThreadCount *
(nThreads*nThreads*guardsPerThreadCount - 1)
n_threads*n_threads*guards_per_phread_count_ *
(n_threads*n_threads*guards_per_phread_count_ - 1)
);
std::vector< int* > additionallyAllocated;
// we should be able to still allocate the guaranteed capacity of
// elements from the pool.
for (unsigned int i = 0; i != guaranteedCapacityPool; ++i) {
int* allocated = testPool->Allocate();
for (unsigned int i = 0; i != guaranteed_capacity_pool_; ++i) {
int* allocated = test_pool_->Allocate();
// allocated is not allowed to be zero
PT_ASSERT(allocated != NULL);
......@@ -390,11 +390,11 @@ void HazardPointerTest2::HazardPointerTest2Post() {
}
// the pool should now be empty
PT_ASSERT(testPool->Allocate() == NULL);
PT_ASSERT(test_pool_->Allocate() == NULL);
// release allocated elements...
for (unsigned int i = 0; i != additionallyAllocated.size(); ++i) {
testPool->Release(additionallyAllocated[i]);
test_pool_->Release(additionallyAllocated[i]);
}
// the additionallyAllocated elements shall be disjoint
......@@ -409,39 +409,39 @@ void HazardPointerTest2::HazardPointerTest2Post() {
// no allocated element should be in any retired list...
for (unsigned int a = 0; a != additionallyAllocated.size(); ++a) {
for (unsigned int i = 0; i != static_cast<unsigned int>(nThreads); ++i) {
for (unsigned int i2 = 0; i2 != static_cast<unsigned int>(nThreads)*
guardsPerThreadCount; ++i2) {
for (unsigned int i = 0; i != static_cast<unsigned int>(n_threads); ++i) {
for (unsigned int i2 = 0; i2 != static_cast<unsigned int>(n_threads)*
guards_per_phread_count_; ++i2) {
PT_ASSERT(
hazardPointer->threadLocalRetiredLists
[i2 + i*nThreads*guardsPerThreadCount] !=
hazard_pointer_->thread_local_retired_lists_
[i2 + i*n_threads*guards_per_phread_count_] !=
additionallyAllocated[a]
);
}
}
}
for (unsigned int i = 0; i != guaranteedCapacityPool; ++i) {
for (unsigned int i = 0; i != guaranteed_capacity_pool_; ++i) {
//in-place new for each array cell
sharedGuarded[i].~Atomic();
shared_guarded_[i].~Atomic();
}
embb::base::Allocation::Free(sharedGuarded);
embb::base::Allocation::Free(shared_guarded_);
for (unsigned int i = 0; i != guaranteedCapacityPool; ++i) {
for (unsigned int i = 0; i != guaranteed_capacity_pool_; ++i) {
//in-place new for each array cell
sharedAllocated[i].~Atomic();
shared_allocated_[i].~Atomic();
}
embb::base::Allocation::Free(sharedAllocated);
embb::base::Allocation::Delete(hazardPointer);
embb::base::Allocation::Free(shared_allocated_);
embb::base::Allocation::Delete(hazard_pointer_);
// after deleting the hazard pointer object, all retired pointers have
// to be returned to the pool!
std::vector<int*> elementsInPool;
int* nextElement;
while ((nextElement = testPool->Allocate()) != NULL) {
while ((nextElement = test_pool_->Allocate()) != NULL) {
for (unsigned int i = 0; i != elementsInPool.size(); ++i) {
// all elements need to be disjoint
PT_ASSERT(elementsInPool[i] != nextElement);
......@@ -451,85 +451,83 @@ void HazardPointerTest2::HazardPointerTest2Post() {
// all elements should have been returned by the hp object, so we should be
// able to acquire all elements.
PT_ASSERT(elementsInPool.size() == poolSizeUsingHazardPointer);
PT_ASSERT(elementsInPool.size() == pool_size_using_hazard_pointer_);
embb::base::Allocation::Delete(testPool);
embb::base::Allocation::Delete(test_pool_);
}
void HazardPointerTest2::HazardPointerTest2ThreadMethod() {
for (;;) {
unsigned int threadIndex;
embb_internal_thread_index(&threadIndex);
unsigned int thread_index;
embb_internal_thread_index(&thread_index);
if (threadIndex == currentMaster) {
if (thread_index == current_master_) {
HazardPointerTest2Master();
}
else {
HazardPointerTest2Slave();
}
sync1.FetchAndAdd(1);
sync1_.FetchAndAdd(1);
// wait until cleanup thread signals to be finished
while (sync1 != 0) {
int expected = nThreads;
int desired = finishMarker;
while (sync1_ != 0) {
int expected = n_threads;
int desired = FINISH_MARKER;
// select thread, responsible for cleanup
if (sync1.CompareAndSwap(expected, desired)) {
if (sync1_.CompareAndSwap(expected, desired)) {
//wipe arrays!
for (unsigned int i = 0; i != guaranteedCapacityPool; ++i) {
sharedGuarded[i] = 0;
sharedAllocated[i] = 0;
for (unsigned int i = 0; i != guaranteed_capacity_pool_; ++i) {
shared_guarded_[i] = 0;
shared_allocated_[i] = 0;
}
// increase master
currentMaster.FetchAndAdd(1);
sync2 = 0;
sync1.Store(0);
current_master_.FetchAndAdd(1);
sync2_ = 0;
sync1_.Store(0);
}
}
// wait for all threads to reach this position
sync2.FetchAndAdd(1);
while (sync2 != static_cast<unsigned int>(nThreads)) {}
sync2_.FetchAndAdd(1);
while (sync2_ != static_cast<unsigned int>(n_threads)) {}
// if each thread was master once, terminate.
if (currentMaster == static_cast<unsigned int>(nThreads)) {
if (current_master_ == static_cast<unsigned int>(n_threads)) {
return;
}
}
}
HazardPointerTest2::HazardPointerTest2() :
nThreads(static_cast<int>
n_threads(static_cast<int>
(partest::TestSuite::GetDefaultNumThreads())),
#ifdef EMBB_PLATFORM_COMPILER_MSVC
#pragma warning(push)
#pragma warning(disable:4355)
#endif
deletePointerCallback(
delete_pointer_callback_(
*this,
&HazardPointerTest2::DeletePointerCallback)
#ifdef EMBB_PLATFORM_COMPILER_MSVC
#pragma warning(pop)
#endif
{
guardsPerThreadCount = 5;
guaranteedCapacityPool = guardsPerThreadCount*nThreads;
poolSizeUsingHazardPointer = guaranteedCapacityPool +
guardsPerThreadCount*nThreads*nThreads;
guards_per_phread_count_ = 5;
guaranteed_capacity_pool_ = guards_per_phread_count_*n_threads;
pool_size_using_hazard_pointer_ = guaranteed_capacity_pool_ +
guards_per_phread_count_*n_threads*n_threads;
embb::base::Thread::GetThreadsMaxCount();
CreateUnit("HazardPointerTestSimulateMemoryWorstCase").
Pre(&HazardPointerTest2::HazardPointerTest2Pre, this).
Add(
&HazardPointerTest2::HazardPointerTest2ThreadMethod,
this, static_cast<size_t>(nThreads)).
this, static_cast<size_t>(n_threads)).
Post(&HazardPointerTest2::HazardPointerTest2Post, this);
}
} // namespace test
} // namespace containers
} // namespace embb
} // namespace embb
\ No newline at end of file
......@@ -36,7 +36,6 @@
namespace embb {
namespace containers {
namespace test {
/**
* @brief a very simple wait-free object pool implementation to have tests
* being independent of the EMBB object pool implementation.
......@@ -51,7 +50,7 @@ class IntObjectTestPool {
static const int FREE_MARKER = 0;
unsigned int poolSize;
IntObjectTestPool(unsigned int poolSize);
IntObjectTestPool(unsigned int pool_size);
~IntObjectTestPool();
......@@ -67,27 +66,10 @@ class IntObjectTestPool {
*
* @param objectPointer the object to be freed
*/
void Release(int* objectPointer);
void Release(int* object_pointer);
};
class HazardPointerTest : public partest::TestCase {
private:
embb::base::Function<void, embb::base::Atomic<int>*> deletePointerCallback;
//used to allocate random stuff, we will just use the pointers, not the
//contents
embb::containers::ObjectPool< embb::base::Atomic<int> >* objectPool;
//used to move pointer between threads
embb::containers::LockFreeStack< embb::base::Atomic<int>* >* stack;
embb::base::Mutex vectorMutex;
embb::containers::internal::HazardPointer<embb::base::Atomic<int>*>*
hazardPointer;
std::vector< embb::base::Atomic<int>* > deletedVector;
int nThreads;
int nElementsPerThread;
int nElements;
public:
/**
* Adds test methods.
......@@ -96,56 +78,71 @@ class HazardPointerTest : public partest::TestCase {
void HazardPointerTest1Pre();
void HazardPointerTest1Post();
void HazardPointerTest1ThreadMethod();
void DeletePointerCallback(embb::base::Atomic<int>* toDelete);
void DeletePointerCallback(embb::base::Atomic<int>* to_delete);
private:
embb::base::Function<void, embb::base::Atomic<int>*> delete_pointer_callback_;
//used to allocate random stuff, we will just use the pointers, not the
//contents
embb::containers::ObjectPool< embb::base::Atomic<int> >* object_pool_;
//used to move pointer between threads
embb::containers::LockFreeStack< embb::base::Atomic<int>* >* stack_;
embb::base::Mutex vector_mutex_;
embb::containers::internal::HazardPointer<embb::base::Atomic<int>*>*
hazard_pointer_;
std::vector< embb::base::Atomic<int>* > deleted_vector_;
int n_threads_;
int n_elements_per_thread_;
int n_elements_;
};
class HazardPointerTest2 : public partest::TestCase {
public:
void DeletePointerCallback(int* to_delete);
bool SetRelativeGuards();
void HazardPointerTest2Master();
void HazardPointerTest2Slave();
void HazardPointerTest2Pre();
void HazardPointerTest2Post();
void HazardPointerTest2ThreadMethod();
HazardPointerTest2();
private:
// number of threads, participating in that test
int nThreads;
int n_threads;
embb::base::Function<void, int*> deletePointerCallback;
embb::base::Function<void, int*> delete_pointer_callback_;
// the thread id of the master
embb::base::Atomic<unsigned int> currentMaster;
embb::base::Atomic<unsigned int> current_master_;
// variables, to synchronize threads. At each point in time, one master,
// the master changes each round until each thread was assigned master once.
embb::base::Atomic<int> sync1;
embb::base::Atomic<unsigned int> sync2;
embb::base::Atomic<int> sync1_;
embb::base::Atomic<unsigned int> sync2_;
unsigned int guardsPerThreadCount;
unsigned int guaranteedCapacityPool;
unsigned int poolSizeUsingHazardPointer;
unsigned int guards_per_phread_count_;
unsigned int guaranteed_capacity_pool_;
unsigned int pool_size_using_hazard_pointer_;
// The threads write here, if they guarded an object successfully. Used to
// determine when all allocated objects were guarded successfully.
embb::base::Atomic<int*>* sharedGuarded;
embb::base::Atomic<int*>* shared_guarded_;
// This array is used by the master, to communicate and share what he has
// allocated with the slaves.
embb::base::Atomic<int*>* sharedAllocated;
embb::base::Atomic<int*>* shared_allocated_;
// Reference to the object pool
IntObjectTestPool* testPool;
embb::containers::internal::HazardPointer<int*>* hazardPointer;
static const int finishMarker = -1;
IntObjectTestPool* test_pool_;
public:
void DeletePointerCallback(int* toDelete);
bool SetRelativeGuards();
void HazardPointerTest2Master();
void HazardPointerTest2Slave();
void HazardPointerTest2Pre();
void HazardPointerTest2Post();
void HazardPointerTest2ThreadMethod();
HazardPointerTest2();
embb::containers::internal::HazardPointer<int*>* hazard_pointer_;
static const int FINISH_MARKER = -1;
};
} // namespace test
} // namespace containers
} // namespace embb
......
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