Disk: NeoMemory: Cache last read sector for one second

This prevents constant re-reads if reading in small chunks
v0.3.0-dev
Paul Hollinsky 2022-02-28 01:55:31 -05:00
parent 4ef8fe8794
commit 4c9d6c5ee7
2 changed files with 34 additions and 21 deletions

View File

@ -12,30 +12,37 @@ optional<uint64_t> NeoMemoryDiskReadDriver::readLogicalDiskAligned(Communication
if(amount != SectorSize)
return 0;
const uint64_t currentSector = pos / SectorSize;
auto msg = com.waitForMessageSync([&currentSector, &com] {
return com.sendCommand(Command::NeoReadMemory, {
MemoryTypeSD,
uint8_t(currentSector & 0xFF),
uint8_t((currentSector >> 8) & 0xFF),
uint8_t((currentSector >> 16) & 0xFF),
uint8_t((currentSector >> 24) & 0xFF),
uint8_t(SectorSize & 0xFF),
uint8_t((SectorSize >> 8) & 0xFF),
uint8_t((SectorSize >> 16) & 0xFF),
uint8_t((SectorSize >> 24) & 0xFF)
});
}, NeoMemorySDRead, timeout);
if(cachePos != pos || std::chrono::steady_clock::now() > cachedAt + CacheTime) {
// The cache does not have this data, go get it
const uint64_t currentSector = pos / SectorSize;
auto msg = com.waitForMessageSync([&currentSector, &com] {
return com.sendCommand(Command::NeoReadMemory, {
MemoryTypeSD,
uint8_t(currentSector & 0xFF),
uint8_t((currentSector >> 8) & 0xFF),
uint8_t((currentSector >> 16) & 0xFF),
uint8_t((currentSector >> 24) & 0xFF),
uint8_t(SectorSize & 0xFF),
uint8_t((SectorSize >> 8) & 0xFF),
uint8_t((SectorSize >> 16) & 0xFF),
uint8_t((SectorSize >> 24) & 0xFF)
});
}, NeoMemorySDRead, timeout);
if(!msg)
return 0;
if(!msg)
return 0;
const auto sdmsg = std::dynamic_pointer_cast<NeoReadMemorySDMessage>(msg);
if(!sdmsg || sdmsg->data.size() != SectorSize) {
report(APIEvent::Type::PacketDecodingError, APIEvent::Severity::Error);
return nullopt;
const auto sdmsg = std::dynamic_pointer_cast<NeoReadMemorySDMessage>(msg);
if(!sdmsg || sdmsg->data.size() != SectorSize) {
report(APIEvent::Type::PacketDecodingError, APIEvent::Severity::Error);
return nullopt;
}
memcpy(cache.data(), sdmsg->data.data(), SectorSize);
cachedAt = std::chrono::steady_clock::now();
cachePos = pos;
}
memcpy(into, sdmsg->data.data(), SectorSize);
memcpy(into, cache.data(), SectorSize);
return SectorSize;
}

View File

@ -5,6 +5,7 @@
#include "icsneo/disk/diskreaddriver.h"
#include <limits>
#include <chrono>
namespace icsneo {
@ -26,6 +27,11 @@ public:
private:
static constexpr const uint8_t MemoryTypeSD = 0x01; // Logical Disk
static constexpr const std::chrono::duration CacheTime = std::chrono::seconds(1);
std::array<uint8_t, SectorSize> cache;
uint64_t cachePos = 0;
std::chrono::time_point<std::chrono::steady_clock> cachedAt;
optional<uint64_t> readLogicalDiskAligned(Communication& com, device_eventhandler_t report,
uint64_t pos, uint8_t* into, uint64_t amount, std::chrono::milliseconds timeout) override;