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Optimized the TLB translations with some caching

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--HG--
extra : convert_revision : f79f863393f918ff9363b2c261f8c0dfec64312e
This commit is contained in:
Ali Saidi 2006-12-15 01:48:09 -05:00
parent fa4293af33
commit 5e70511bff
2 changed files with 106 additions and 32 deletions
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127
src/arch/sparc/tlb.cc
View file

@ -45,7 +45,7 @@ namespace SparcISA
{
TLB::TLB(const std::string &name, int s)
: SimObject(name), size(s)
: SimObject(name), size(s), usedEntries(0), cacheValid(false)
{
// To make this work you'll have to change the hypervisor and OS
if (size > 64)
@ -79,6 +79,8 @@ TLB::insert(Addr va, int partition_id, int context_id, bool real,
TlbEntry *new_entry = NULL;
int x;
cacheValid = false;
DPRINTF(TLB, "TLB: Inserting TLB Entry; va=%#x pa=%#x pid=%d cid=%d r=%d\n",
va, PTE.paddr(), partition_id, context_id, (int)real);
@ -194,6 +196,8 @@ TLB::demapPage(Addr va, int partition_id, bool real, int context_id)
TlbRange tr;
MapIter i;
cacheValid = false;
// Assemble full address structure
tr.va = va;
tr.size = va + MachineBytes;
@ -217,6 +221,7 @@ void
TLB::demapContext(int partition_id, int context_id)
{
int x;
cacheValid = false;
for (x = 0; x < size; x++) {
if (tlb[x].range.contextId == context_id &&
tlb[x].range.partitionId == partition_id) {
@ -234,6 +239,7 @@ void
TLB::demapAll(int partition_id)
{
int x;
cacheValid = false;
for (x = 0; x < size; x++) {
if (!tlb[x].pte.locked() && tlb[x].range.partitionId == partition_id) {
tlb[x].valid = false;
@ -250,6 +256,8 @@ void
TLB::invalidateAll()
{
int x;
cacheValid = false;
for (x = 0; x < size; x++) {
tlb[x].valid = false;
}
@ -337,7 +345,7 @@ DTB::writeSfr(ThreadContext *tc, Addr a, bool write, ContextType ct,
tc->setMiscRegWithEffect(MISCREG_MMU_DTLB_SFAR, a);
}
void
void
DTB::writeTagAccess(ThreadContext *tc, Addr va, int context)
{
TLB::writeTagAccess(tc, MISCREG_MMU_DTLB_TAG_ACCESS, va, context);
@ -350,6 +358,29 @@ ITB::translate(RequestPtr &req, ThreadContext *tc)
{
uint64_t tlbdata = tc->readMiscReg(MISCREG_TLB_DATA);
Addr vaddr = req->getVaddr();
TlbEntry *e;
assert(req->getAsi() == ASI_IMPLICIT);
DPRINTF(TLB, "TLB: ITB Request to translate va=%#x size=%d\n",
vaddr, req->getSize());
// Be fast if we can!
if (cacheValid && cacheState == tlbdata) {
if (cacheEntry) {
if (cacheEntry->range.va < vaddr + sizeof(MachInst) &&
cacheEntry->range.va + cacheEntry->range.size >= vaddr) {
req->setPaddr(cacheEntry->pte.paddr() & ~(cacheEntry->pte.size()-1) |
vaddr & cacheEntry->pte.size()-1 );
return NoFault;
}
} else {
req->setPaddr(vaddr & PAddrImplMask);
return NoFault;
}
}
bool hpriv = bits(tlbdata,0,0);
bool red = bits(tlbdata,1,1);
bool priv = bits(tlbdata,2,2);
@ -359,21 +390,14 @@ ITB::translate(RequestPtr &req, ThreadContext *tc)
int part_id = bits(tlbdata,15,8);
int tl = bits(tlbdata,18,16);
int pri_context = bits(tlbdata,47,32);
Addr vaddr = req->getVaddr();
int context;
ContextType ct;
int asi;
bool real = false;
TlbEntry *e;
DPRINTF(TLB, "TLB: ITB Request to translate va=%#x size=%d\n",
vaddr, req->getSize());
DPRINTF(TLB, "TLB: priv:%d hpriv:%d red:%d lsuim:%d part_id: %#X\n",
priv, hpriv, red, lsu_im, part_id);
assert(req->getAsi() == ASI_IMPLICIT);
if (tl > 0) {
asi = ASI_N;
ct = Nucleus;
@ -385,12 +409,15 @@ ITB::translate(RequestPtr &req, ThreadContext *tc)
}
if ( hpriv || red ) {
req->setPaddr(req->getVaddr() & PAddrImplMask);
cacheValid = true;
cacheState = tlbdata;
cacheEntry = NULL;
req->setPaddr(vaddr & PAddrImplMask);
return NoFault;
}
// If the asi is unaligned trap
if (vaddr & req->getSize()-1) {
// If the access is unaligned trap
if (vaddr & 0x3) {
writeSfsr(tc, false, ct, false, OtherFault, asi);
return new MemAddressNotAligned;
}
@ -404,7 +431,7 @@ ITB::translate(RequestPtr &req, ThreadContext *tc)
}
if (!lsu_im) {
e = lookup(req->getVaddr(), part_id, true);
e = lookup(vaddr, part_id, true);
real = true;
context = 0;
} else {
@ -426,9 +453,14 @@ ITB::translate(RequestPtr &req, ThreadContext *tc)
return new InstructionAccessException;
}
// cache translation date for next translation
cacheValid = true;
cacheState = tlbdata;
cacheEntry = e;
req->setPaddr(e->pte.paddr() & ~(e->pte.size()-1) |
req->getVaddr() & e->pte.size()-1 );
DPRINTF(TLB, "TLB: %#X -> %#X\n", req->getVaddr(), req->getPaddr());
vaddr & e->pte.size()-1 );
DPRINTF(TLB, "TLB: %#X -> %#X\n", vaddr, req->getPaddr());
return NoFault;
}
@ -439,8 +471,40 @@ DTB::translate(RequestPtr &req, ThreadContext *tc, bool write)
{
/* @todo this could really use some profiling and fixing to make it faster! */
uint64_t tlbdata = tc->readMiscReg(MISCREG_TLB_DATA);
Addr vaddr = req->getVaddr();
Addr size = req->getSize();
ASI asi;
asi = (ASI)req->getAsi();
bool implicit = false;
bool hpriv = bits(tlbdata,0,0);
DPRINTF(TLB, "TLB: DTB Request to translate va=%#x size=%d asi=%#x\n",
vaddr, size, asi);
if (asi == ASI_IMPLICIT)
implicit = true;
if (hpriv && implicit) {
req->setPaddr(vaddr & PAddrImplMask);
return NoFault;
}
// Be fast if we can!
if (cacheValid && cacheState == tlbdata) {
if (cacheEntry[0] && cacheAsi[0] == asi && cacheEntry[0]->range.va < vaddr + size &&
cacheEntry[0]->range.va + cacheEntry[0]->range.size >= vaddr) {
req->setPaddr(cacheEntry[0]->pte.paddr() & ~(cacheEntry[0]->pte.size()-1) |
vaddr & cacheEntry[0]->pte.size()-1 );
return NoFault;
}
if (cacheEntry[1] && cacheAsi[1] == asi && cacheEntry[1]->range.va < vaddr + size &&
cacheEntry[1]->range.va + cacheEntry[1]->range.size >= vaddr) {
req->setPaddr(cacheEntry[1]->pte.paddr() & ~(cacheEntry[1]->pte.size()-1) |
vaddr & cacheEntry[1]->pte.size()-1 );
return NoFault;
}
}
bool red = bits(tlbdata,1,1);
bool priv = bits(tlbdata,2,2);
bool addr_mask = bits(tlbdata,3,3);
@ -451,23 +515,14 @@ DTB::translate(RequestPtr &req, ThreadContext *tc, bool write)
int pri_context = bits(tlbdata,47,32);
int sec_context = bits(tlbdata,47,32);
bool implicit = false;
bool real = false;
Addr vaddr = req->getVaddr();
Addr size = req->getSize();
ContextType ct = Primary;
int context = 0;
ASI asi;
TlbEntry *e;
asi = (ASI)req->getAsi();
DPRINTF(TLB, "TLB: DTB Request to translate va=%#x size=%d asi=%#x\n",
vaddr, size, asi);
DPRINTF(TLB, "TLB: priv:%d hpriv:%d red:%d lsudm:%d part_id: %#X\n",
priv, hpriv, red, lsu_dm, part_id);
if (asi == ASI_IMPLICIT)
implicit = true;
if (implicit) {
if (tl > 0) {
@ -562,11 +617,11 @@ continueDtbFlow:
};
if (hpriv && (implicit || (!AsiIsAsIfUser(asi) && !AsiIsReal(asi)))) {
req->setPaddr(req->getVaddr() & PAddrImplMask);
req->setPaddr(vaddr & PAddrImplMask);
return NoFault;
}
e = lookup(req->getVaddr(), part_id, real, context);
e = lookup(vaddr, part_id, real, context);
if (e == NULL || !e->valid) {
tc->setMiscReg(MISCREG_MMU_DTLB_TAG_ACCESS,
@ -599,9 +654,21 @@ continueDtbFlow:
return new DataAccessException;
}
// cache translation date for next translation
cacheValid = true;
cacheState = tlbdata;
if (cacheEntry[0] != e && cacheEntry[1] != e) {
cacheEntry[1] = cacheEntry[0];
cacheEntry[0] = e;
cacheAsi[1] = cacheAsi[0];
cacheAsi[0] = asi;
if (implicit)
cacheAsi[0] = (ASI)0;
}
req->setPaddr(e->pte.paddr() & ~(e->pte.size()-1) |
req->getVaddr() & e->pte.size()-1);
DPRINTF(TLB, "TLB: %#X -> %#X\n", req->getVaddr(), req->getPaddr());
vaddr & e->pte.size()-1);
DPRINTF(TLB, "TLB: %#X -> %#X\n", vaddr, req->getPaddr());
return NoFault;
/** Normal flow ends here. */
@ -773,8 +840,6 @@ DTB::doMmuRegRead(ThreadContext *tc, Packet *pkt)
data = mbits(tsbtemp,63,13);
data |= temp >> (9 + bits(cnftemp,2,0) * 3) &
mbits((uint64_t)-1ll,12+bits(tsbtemp,3,0), 4);
warn("base addr: %#X tag access: %#X page size: %#X tsb size: %#X\n",
bits(tsbtemp,63,13), temp, bits(cnftemp,2,0), bits(tsbtemp,3,0));
pkt->set(data);
break;
case ASI_DMMU_TSB_PS1_PTR_REG:

11
src/arch/sparc/tlb.hh
View file

@ -31,6 +31,7 @@
#ifndef __ARCH_SPARC_TLB_HH__
#define __ARCH_SPARC_TLB_HH__
#include "arch/sparc/asi.hh"
#include "arch/sparc/tlb_map.hh"
#include "base/misc.hh"
#include "mem/request.hh"
@ -54,6 +55,9 @@ class TLB : public SimObject
int size;
int usedEntries;
uint64_t cacheState;
bool cacheValid;
enum FaultTypes {
OtherFault = 0,
PrivViolation = 0x1,
@ -131,6 +135,7 @@ class ITB : public TLB
public:
ITB(const std::string &name, int size) : TLB(name, size)
{
cacheEntry = NULL;
}
Fault translate(RequestPtr &req, ThreadContext *tc);
@ -138,6 +143,7 @@ class ITB : public TLB
void writeSfsr(ThreadContext *tc, bool write, ContextType ct,
bool se, FaultTypes ft, int asi);
void writeTagAccess(ThreadContext *tc, Addr va, int context);
TlbEntry *cacheEntry;
friend class DTB;
};
@ -146,6 +152,8 @@ class DTB : public TLB
public:
DTB(const std::string &name, int size) : TLB(name, size)
{
cacheEntry[0] = NULL;
cacheEntry[1] = NULL;
}
Fault translate(RequestPtr &req, ThreadContext *tc, bool write);
@ -157,7 +165,8 @@ class DTB : public TLB
bool se, FaultTypes ft, int asi);
void writeTagAccess(ThreadContext *tc, Addr va, int context);
TlbEntry *cacheEntry[2];
ASI cacheAsi[2];
};
}