File dirty.cpp

namespace faabric

namespace util

Functions

std::shared_ptr<DirtyTracker> getDirtyTracker()

Returns the dirty tracker singleton. The dirty tracking mode is determined in the system config.

void resetDirtyTracker()

Resets the dirty tracker singleton (e.g. if the config has been changed).

void *pageAlignAddress(void *faultAddr)

Variables

static thread_local DirtyTrackingRecord tracking

static ThreadSafeDirtyTrackingRecord globalTracking

static std::shared_ptr<DirtyTracker> tracker = nullptr

static long uffd = -1

static bool uffdWriteProtect = false

static bool uffdSigbus = false

static int closeFd = -1

static std::shared_ptr<std::jthread> eventThread = nullptr

class DirtyTrackingRecord

Wrapper around the actual bookkeeping behind dirty tracking. This is deliberately not thread-safe as it will only ever be used in TLS for signal handlers.

Subclassed by faabric::util::ThreadSafeDirtyTrackingRecord

Public Functions

DirtyTrackingRecord() = default

inline virtual void trackRegion(std::span<uint8_t> region)

inline virtual void markPage(void *addr)

inline virtual bool isInitialised()

inline virtual int getNPages()

inline virtual std::vector<char> getDirtyFlags()

inline virtual void reset()

Protected Attributes

int nPages = 0

std::vector<char> dirtyFlags

uint8_t *regionBase = nullptr

uint8_t *regionTop = nullptr

class ThreadSafeDirtyTrackingRecord : public faabric::util::DirtyTrackingRecord

Thread-safe wrapper around dirty tracking data, necessary for use with the background event thread in the userfaultfd tracker. Although the logic around the interaction between the event thread and the main thread should in theory protect against concurrent accesses, we need this to keep TSan happy.

Public Functions

ThreadSafeDirtyTrackingRecord() = default

inline virtual void trackRegion(std::span<uint8_t> region) override

inline virtual void markPage(void *addr) override

inline virtual std::vector<char> getDirtyFlags() override

inline virtual bool isInitialised() override

inline virtual int getNPages() override

inline virtual void reset() override

Private Members

std::shared_mutex mx