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author | Derek Hower <drh5@cs.wisc.edu> | 2009-11-13 09:43:39 -0600 |
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committer | Derek Hower <drh5@cs.wisc.edu> | 2009-11-13 09:43:39 -0600 |
commit | 2ee04d65873bac7a91d9d309eff79d13b8cc8103 (patch) | |
tree | 710f231e542986a01bf48cdd42f510b7f2531408 /src/mem/ruby/system/MemoryVector.hh | |
parent | ceb8fde914aebc3568d55d50defb8aed36717ea6 (diff) | |
download | gem5-2ee04d65873bac7a91d9d309eff79d13b8cc8103.tar.xz |
ruby: reduce the memory usage of ruby by making memory vector page based
Diffstat (limited to 'src/mem/ruby/system/MemoryVector.hh')
-rw-r--r-- | src/mem/ruby/system/MemoryVector.hh | 72 |
1 files changed, 58 insertions, 14 deletions
diff --git a/src/mem/ruby/system/MemoryVector.hh b/src/mem/ruby/system/MemoryVector.hh index c5f3cea7f..775244840 100644 --- a/src/mem/ruby/system/MemoryVector.hh +++ b/src/mem/ruby/system/MemoryVector.hh @@ -21,61 +21,105 @@ class MemoryVector { void write(const Address & paddr, uint8* data, int len); uint8* read(const Address & paddr, uint8* data, int len); - private: - uint8* getBlockPtr(const Address & paddr); +private: + uint8* getBlockPtr(const PhysAddress & addr); uint32 m_size; - uint8* m_vec; + uint8** m_pages; + uint32 m_num_pages; + const uint32 m_page_offset_mask; }; inline MemoryVector::MemoryVector() + : m_page_offset_mask(4095) { m_size = 0; - m_vec = NULL; + m_num_pages = 0; + m_pages = NULL; } inline MemoryVector::MemoryVector(uint32 size) + : m_page_offset_mask(4095) { - m_size = size; - m_vec = new uint8[size]; + setSize(size); } inline MemoryVector::~MemoryVector() { - delete [] m_vec; + for (int i=0; i<m_num_pages; i++) { + if (m_pages[i] != 0) { + delete [] m_pages[i]; + } + } + delete [] m_pages; } inline void MemoryVector::setSize(uint32 size) { + if (m_pages != NULL){ + for (int i=0; i<m_num_pages; i++) { + if (m_pages[i] != 0) { + delete [] m_pages[i]; + } + } + delete [] m_pages; + } m_size = size; - if (m_vec != NULL) - delete [] m_vec; - m_vec = new uint8[size]; + assert(size%4096 == 0); + m_num_pages = size >> 12; + m_pages = new uint8*[m_num_pages]; + memset(m_pages, 0, m_num_pages * sizeof(uint8*)); } inline void MemoryVector::write(const Address & paddr, uint8* data, int len) { assert(paddr.getAddress() + len <= m_size); - memcpy(m_vec + paddr.getAddress(), data, len); + uint32 page_num = paddr.getAddress() >> 12; + if (m_pages[page_num] == 0) { + bool all_zeros = true; + for (int i=0;i<len;i++) { + if (data[i] != 0) { + all_zeros = false; + break; + } + } + if (all_zeros) return; + m_pages[page_num] = new uint8[4096]; + memset(m_pages[page_num], 0, 4096); + uint32 offset = paddr.getAddress() & m_page_offset_mask; + memcpy(&m_pages[page_num][offset], data, len); + } else { + memcpy(&m_pages[page_num][paddr.getAddress()&m_page_offset_mask], data, len); + } } inline uint8* MemoryVector::read(const Address & paddr, uint8* data, int len) { assert(paddr.getAddress() + len <= m_size); - memcpy(data, m_vec + paddr.getAddress(), len); + uint32 page_num = paddr.getAddress() >> 12; + if (m_pages[page_num] == 0) { + memset(data, 0, len); + } else { + memcpy(data, &m_pages[page_num][paddr.getAddress()&m_page_offset_mask], len); + } return data; } inline -uint8* MemoryVector::getBlockPtr(const Address & paddr) +uint8* MemoryVector::getBlockPtr(const PhysAddress & paddr) { - return m_vec + paddr.getAddress(); + uint32 page_num = paddr.getAddress() >> 12; + if (m_pages[page_num] == 0) { + m_pages[page_num] = new uint8[4096]; + memset(m_pages[page_num], 0, 4096); + } + return &m_pages[page_num][paddr.getAddress()&m_page_offset_mask]; } #endif // MEMORYVECTOR_H |