| sc::ShmMemoryGrp(3) | MPQC | sc::ShmMemoryGrp(3) |
sc::ShmMemoryGrp - The ShmMemoryGrp concrete class provides an implementation of MsgMemoryGrp.
#include <memshm.h>
Inherits sc::MsgMemoryGrp.
ShmMemoryGrp (const Ref< MessageGrp >
&msg)
ShmMemoryGrp (const Ref< KeyVal > &)
void set_localsize (size_t)
Set the size of locally held memory. void * localdata ()
Returns a pointer to the local data. void * obtain_readwrite
(distsize_t offset, int size)
Only one thread can have an unreleased obtain_readwrite at a time. void *
obtain_readonly (distsize_t offset, int size)
This gives read access to the memory location. No locking is done. void *
obtain_writeonly (distsize_t offset, int size)
This gives write access to the memory location. No locking is done. void
release_readonly (void *data, distsize_t offset, int
size)
This is called when read access is no longer needed. void
release_writeonly (void *data, distsize_t offset, int
size)
This is called when write access is no longer needed. void
release_readwrite (void *data, distsize_t offset, int
size)
This is called when read/write access is no longer needed. void print
(std::ostream &o=ExEnv::out0()) const
Prints out information about the object.
The ShmMemoryGrp concrete class provides an implementation of MsgMemoryGrp.
It uses SYSV IPC to provided shared memory in a system that provide shared memory in hardware. It is very fast and reliable.
Returns a pointer to the local data.
Implements sc::MemoryGrp.
This gives read access to the memory location. No locking is done.
Implements sc::MemoryGrp.
Only one thread can have an unreleased obtain_readwrite at a time. The actual memory region locked can be larger than that requested. If the memory region is already locked this will block. For this reason, data should be held as read/write for as short a time as possible.
Implements sc::MemoryGrp.
This gives write access to the memory location. No locking is done.
Implements sc::MemoryGrp.
Prints out information about the object.
Reimplemented from sc::MemoryGrp.
This is called when read access is no longer needed.
Implements sc::MemoryGrp.
This is called when read/write access is no longer needed. The memory will be unlocked.
Implements sc::MemoryGrp.
This is called when write access is no longer needed.
Implements sc::MemoryGrp.
Set the size of locally held memory. When memory is accessed using a global offset counting starts at node 0 and proceeds up to node n() - 1.
Reimplemented from sc::MsgMemoryGrp.
Generated automatically by Doxygen for MPQC from the source code.
| Fri Dec 2 2022 | Version 2.3.1 |