On Wed, Nov 26, 2014 at 11:47 AM, Pavel Dovgaluk <pavel.dovga...@ispras.ru> wrote: > That covermail was wrong. Here is the correct one: > > This set of patches is related to the reverse execution and deterministic > replay of qemu execution This implementation of deterministic replay can > be used for deterministic debugging of guest code through gdb remote > interface. > > These patches include only core function of the replay, > excluding the support for replaying serial, audio, network, and USB devices' > operations. Reverse debugging and monitor commands were also excluded to > be submitted later as separate patches. > > Execution recording writes non-deterministic events log, which can be later > used for replaying the execution anywhere and for unlimited number of times. > It also supports checkpointing for faster rewinding during reverse debugging. > Execution replaying reads the log and replays all non-deterministic events > including external input, hardware clocks, and interrupts. > > Deterministic replay has the following features: > * Deterministically replays whole system execution and all contents of the > memory, > state of the hadrware devices, clocks, and screen of the VM. > * Writes execution log into the file for latter replaying for multiple times > on different machines. > * Supports i386, x86_64, and ARM hardware platforms.
This patch series is really impressive, hats off! I wonder what would have to be done to add support for SPARC-64? Since has a PCI bus, I guess the support in atapi and usb devices is already there. Is anything beyond translate.c has to be adjusted? Artyom > * Performs deterministic replay of all operations with keyboard and mouse > input devices. > * Supports auto-checkpointing for convenient reverse debugging. > > Usage of the record/replay: > * First, record the execution, by adding the following string to the command > line: > '-record fname=replay.bin -icount 7 -net none'. Block devices' images are > not > actually changed in the recording mode, because all of the changes are > written to the temporary overlay file. > * Then you can replay it for the multiple times by using another command > line option: '-replay fname=replay.bin -icount 7 -net none' > * '-net none' option should also be specified if network replay patches > are not applied. > > Paper with short description of deterministic replay implementation: > http://www.computer.org/csdl/proceedings/csmr/2012/4666/00/4666a553-abs.html > > Modifications of qemu include: > * wrappers for clock and time functions to save their return values in the > log > * saving different asynchronous events (e.g. system shutdown) into the log > * synchronization of the bottom halves execution > * synchronization of the threads from thread pool > * recording/replaying user input (mouse and keyboard) > * adding internal events for cpu and io synchronization > > v5 changes: > * Minor changes. > * Used fixed-width integer types for read/write functions (as suggested by > Alex Bennee) > * Moved savevm-related code out of the core. > * Added new traced clock for deterministic virtual clock warping (as > suggested by Paolo Bonzini) > * Fixed exception_index reset for user mode (as suggested by Paolo Bonzini) > * Adopted Paolo's icount patches > * Fixed hardware interrupts replaying > > v4 changes: > * Updated block drivers to support new bdrv_open interface. > * Moved migration patches into separate series (as suggested by Paolo > Bonzini) > * Fixed a bug in replay_break operation. > * Fixed rtl8139 migration for replay. > * Fixed 'period' parameter processing for record mode. > * Fixed bug in 'reverse-stepi' implementation. > * Fixed replay without making any snapshots (even the starting one). > * Moved core replay patches into the separate series. > * Fixed reverse step and reverse continue support. > * Fixed several bugs in icount subsystem. > * Reusing native qemu icount for replay instructions counting. > * Separated core patches into their own series. > > v3 changes: > * Fixed bug with replay of the aio write operations. > * Added virtual clock based on replay icount. > * Removed duplicated saving of interrupt_request CPU field. > * Fixed some coding style issues. > * Renamed QMP commands for controlling reverse execution (as suggested by > Eric Blake) > * Replay mode and submode implemented as QAPI enumerations (as suggested by > Eric Blake) > * Added description and example for replay-info command (as suggested by > Eric Blake) > * Added information about the current breakpoint to the output of > replay-info (as suggested by Eric Blake) > * Updated version id for HPET vmstate (as suggested by Paolo Bonzini) > * Removed static fields from parallel vmstate (as suggested by Paolo Bonzini) > * New vmstate fields for mc146818rtc, pckbd, kvmapic, serial, fdc, rtl8139 > moved to subsection (as suggested by Paolo Bonzini) > * Disabled textmode cursor blinking, when virtual machine is stopped (as > suggested by Paolo Bonzini) > * Extracted saving of exception_index to separate patch (as suggested by > Paolo Bonzini) > > v2 changes: > * Patches are split to be reviewable and bisectable (as suggested by Kirill > Batuzov) > * Added QMP versions of replay commands (as suggested by Eric Blake) > * Removed some optional features of replay to make patches cleaner > * Minor changes and code cleanup were made > > > -- Regards, Artyom Tarasenko SPARC and PPC PReP under qemu blog: http://tyom.blogspot.com/search/label/qemu