deadtrickster

;; https://en.wikipedia.org/wiki/Readers%E2%80%93writers_problem

(defstruct rwlock
  (rlock (bt:make-lock))
  (wlock (bt:make-lock))
  (rtrylock (bt:make-lock))
  (resource (bt:make-lock))
  (rcount 0)
  (wcount 0))

deadtrickster

Direct links to free Springer maths books (pdf versions)

duplicates = multiple editions

A Classical Introduction to Modern Number Theory,Kenneth IrelandMichael Rosen

A Classical Introduction to Modern Number Theory,Kenneth IrelandMichael Rosen

A Course in Arithmetic,Jean-Pierre Serre

deadtrickster

https://github.com/elixir-lang/elixir/blob/f4b5e43fc10f6fd6ef84a5ceda8aa3c37131b5a1/lib/elixir/src/elixir_def.erl
https://github.com/elixir-lang/elixir/blob/133fc0c40ebdc179b14d51f3e853e3264fd18b5f/lib/elixir/src/elixir_locals.erl
https://github.com/elixir-lang/elixir/blob/f33c00bc73650c9ff6ab641b1ad88be9c5c69fc8/lib/elixir/src/elixir_dispatch.erl

deadtrickster

Keybase proof

I hereby claim:

• I am deadtrickster on github.
• I am deadtrickster (https://keybase.io/deadtrickster) on keybase.
• I have a public key whose fingerprint is 8838 3471 5B97 B18A 7B12 F958 76A9 29E1 8553 C165

To claim this, I am signing this object:

deadtrickster

Isolated test

Before:

7> benchmark:run(100, 1*1000*1000).
{1190.6,100000000}

After:

deadtrickster

(let* ((mailbox (sb-concurrency:make-mailbox))
       (event-base (make-instance 'iolib:event-base))
       (control-fd (eventfd:eventfd.new 0))
       (thread (bt:make-thread (lambda ()
                                 (iolib:set-io-handler event-base
                                                       control-fd
                                                       :read (lambda (fd e ex)
                                                               (declare (ignorable fd e ex))
                                                               (log:debug (eventfd.read control-fd))))
                                 (loop (iolib:event-dispatch event-base :one-shot t))))))

deadtrickster

(defun receive-message (mailbox &key timeout)
  "Removes the oldest message from MAILBOX and returns it as the primary
value, and a secondary value of T. If MAILBOX is empty waits until a message
arrives.
If TIMEOUT is provided, and no message arrives within the specified interval,
returns primary and secondary value of NIL."
  (tagbody
     ;; Disable interrupts for keeping semaphore count in sync with
     ;; #msgs in the mailbox.
     (sb-sys:without-interrupts

deadtrickster

(with-pinned-objects (queue me)
  (setf (waitqueue-token queue) me)
  (release-mutex mutex)
  ;; Now we go to sleep using futex-wait. If anyone else
  ;; manages to grab MUTEX and call CONDITION-NOTIFY during
  ;; this comment, it will change the token, and so futex-wait
  ;; returns immediately instead of sleeping. Ergo, no lost
  ;; wakeup. We may get spurious wakeups, but that's ok.
  (setf status
        (case (allow-with-interrupts

deadtrickster

/* stop all other threads by sending them SIG_STOP_FOR_GC */
    for(p=all_threads; p; p=p->next) {
        gc_assert(p->os_thread != 0);
        FSHOW_SIGNAL((stderr,"/gc_stop_the_world: thread=%lu, state=%x\n",
                      p->os_thread, thread_state(p)));
        if((p!=th) && ((thread_state(p)==STATE_RUNNING))) {
            FSHOW_SIGNAL((stderr,"/gc_stop_the_world: suspending thread %lu\n",
                          p->os_thread));
            /* We already hold all_thread_lock, P can become DEAD but
             * cannot exit, ergo it's safe to use pthread_kill. */

deadtrickster

(ql:quickload :iolib)
(ql:quickload :eventfd)

(setf control-fd (eventfd:eventfd.new 0))
(setf event-base (make-instance 'iolib:event-base))
(setf thread (bt:make-thread (lambda ()
                                 (iolib:set-io-handler event-base
                                                       control-fd
                                                       :read (lambda (fd e ex)
                                                               (declare (ignorable fd e ex)))