this patch fixes several critical issues in the task scheduler:
1. vm integration for computed goto dispatch mode:
- added task switching check in NEXT macro for computed goto
- previous implementation only worked with switch dispatch mode
- now Task.pass properly yields control to other tasks
2. task lifecycle tracking:
- added 'started' flag to mrb_task structure
- fixed first-run detection to avoid popping callinfo multiple times
- vm overwrites context status during execution, making it unreliable
3. removed mrblib/task.rb:
- empty Ruby method stubs were overriding C implementations
- all task methods now properly implemented in C
4. cleaned up task scheduler loop:
- proper task completion detection using switching flag
- round-robin scheduling for tasks at same priority
- clean scheduler exit when all tasks complete
tasks now cooperatively yield with Task.pass and complete cleanly.
Co-authored-by: Claude <noreply@anthropic.com>
add hardware abstraction layer with posix implementation:
- setitimer: generates periodic sigalrm for tick-based scheduling
- signal handler: calls mrb_tick on each timer interrupt
- sigprocmask: enables/disables interrupts by blocking sigalrm
- usleep: idle cpu implementation for posix platforms
the hal is initialized during gem init and starts the periodic
timer automatically. non-posix platforms get stub implementations.
tick period is configurable via MRB_TICK_UNIT (default 4ms).
Co-authored-by: Claude <noreply@anthropic.com>
implement task class methods:
- Task.new: creates task with block, optional name and priority
- Task.current: returns currently running task
- Task.list: returns array of all tasks in all queues
- Task.pass: yields to other tasks voluntarily
- Task.get: finds task by name
implement task instance methods:
- status: returns task status as symbol (:DORMANT, :READY, etc)
- name/name=: get/set task name
- priority/priority=: get/set priority with queue re-sorting
- suspend/resume: manual task suspension and resumption
- terminate: forcibly terminate task and wake joiners
- join: wait for task completion
the api provides full control over task lifecycle and scheduling
from ruby code while maintaining thread safety through irq protection.
Co-authored-by: Claude <noreply@anthropic.com>
implement core scheduling components:
- mrb_tick: tick handler for timeslice countdown and sleep wakeup
- mrb_tasks_run: main scheduler loop with context switching
- sleep operations: sleep_ms_impl, sleep, sleep_ms
- hal stub implementations for compilation (temporary)
the scheduler uses tick-based preemption with round-robin at same
priority. sleeping tasks wake when their tick count expires.
completed tasks move to dormant queue and wake any waiting joiners.
Co-authored-by: Claude <noreply@anthropic.com>
add priority queue operations:
- q_get_queue: select queue based on task status
- q_insert_task: priority-based insertion (lower number = higher priority)
- q_delete_task: remove task from queue
- q_find_task: search for task in all queues
add task lifecycle functions:
- task_alloc: allocate and zero-initialize task structure
- task_free: free task and associated context (stack + callinfo)
- task_init_context: initialize execution context similar to fiber
* allocate vm stack with dynamic sizing based on irep->nregs
* allocate callinfo stack
* setup callinfo with proc and target class
* set context status to MRB_TASK_CREATED
this completes phase 2 of the task scheduler implementation.
Co-authored-by: Claude <noreply@anthropic.com>
replace confusing "tcb" (task control block) terminology with clearer
"mrb_task" naming:
- struct mrb_tcb -> struct mrb_task
- update mrb_task_state to use mrb_task pointers
- rename internal functions to avoid naming conflicts:
- mrb_task_new -> task_alloc
- mrb_task_free (lifecycle) -> task_free
- update field names for clarity:
- tcb_join -> join
- task (ruby object) -> self
- value (return value) -> result
this makes the code more readable and follows mruby naming conventions
like mrb_context, mrb_irep, etc.
Co-authored-by: Claude <noreply@anthropic.com>
extend mrb_fiber_state enum with task-specific states:
- MRB_TASK_CREATED: task context initialized
- MRB_TASK_STOPPED: task execution finished
add mrb_task_state structure to mrb_state:
- task queues array (dormant, ready, waiting, suspended)
- tick counter for scheduling
- wakeup_tick for sleep timing
- switching flag for context switches
remove duplicate mrb_task_state definition from task.h since it is
now defined in include/mruby.h. all changes guarded by
MRB_USE_TASK_SCHEDULER for zero overhead when disabled.
Co-authored-by: Claude <noreply@anthropic.com>
create mruby-task gem directory structure with:
- mrbgem.rake: gem specification with task scheduler define
- include/task.h: tcb structure and core scheduler declarations
- src/task.c: implementation skeleton with empty method stubs
- mrblib/task.rb: ruby api documentation and task::stat class
all methods have empty bodies ready for implementation.
Co-authored-by: Claude <noreply@anthropic.com>
Yukihiro "Matz" Matsumoto