Changeset 22226e4 for libcfa/src/concurrency/kernel.hfa

Timestamp:

Mar 18, 2022, 12:42:39 PM (3 years ago)

Author:

Thierry Delisle <tdelisle@…>

Branches:

ADT, ast-experimental, enum, master, pthread-emulation, qualifiedEnum

Children:

0b4ddb71, 51239d1b

Parents:

3bc69f2

Message:

Tentative fix for spurious deadlock in some concurrency tests

File:

• libcfa/src/concurrency/kernel.hfa (modified) (3 diffs)

libcfa/src/concurrency/kernel.hfa

@@ -48 +48 @@
 extern struct cluster * mainCluster;
 
-// Processor id, required for scheduling threads
-
-
+// Coroutine used py processors for the 2-step context switch
 coroutine processorCtx_t {
         struct processor * proc;
 };
 
-
+struct io_future_t;
+
+// Information needed for idle sleep
 struct __fd_waitctx {
-        volatile int fd;
+        // semaphore/future like object
+        // values can be 0, 1 or some file descriptor.
+        // 0 - is the default state
+        // 1 - means the proc should wake-up immediately
+        // FD - means the proc is going asleep and should be woken by writing to the FD.
+        volatile int sem;
+
+        // The event FD that corresponds to this processor
+        int evfd;
+
+        // buffer into which the proc will read from evfd
+        // unused if not using io_uring for idle sleep
+        void * rdbuf;
+
+        // future use to track the read of the eventfd
+        // unused if not using io_uring for idle sleep
+        io_future_t * ftr;
 };
 
@@ -103 +119 @@
         bool pending_preemption;
 
-        // Idle lock (kernel semaphore)
-        int idle_fd;
-
-        // Idle waitctx
+        // context for idle sleep
         struct __fd_waitctx idle_wctx;
 
@@ -168 +181 @@
         volatile unsigned id;
 };
-
-// //TODO adjust cache size to ARCHITECTURE
-// // Structure holding the ready queue
-// struct __ready_queue_t {
-//      // Data tracking the actual lanes
-//      // On a seperate cacheline from the used struct since
-//      // used can change on each push/pop but this data
-//      // only changes on shrink/grow
-//      struct {
-//              // Arary of lanes
-//              __intrusive_lane_t * volatile data;
-
-//              __cache_id_t * volatile caches;
-
-//              // Number of lanes (empty or not)
-//              volatile size_t count;
-//      } lanes;
-// };
-
-// void  ?{}(__ready_queue_t & this);
-// void ^?{}(__ready_queue_t & this);
 
 // Idle Sleep