Changeset 1095ccd

Timestamp:

Aug 14, 2020, 5:32:32 PM (4 years ago)

Author:

Thierry Delisle <tdelisle@…>

Branches:

ADT, arm-eh, ast-experimental, enum, forall-pointer-decay, jacob/cs343-translation, master, new-ast, new-ast-unique-expr, pthread-emulation, qualifiedEnum

Children:

d2b5d2d

Parents:

a5bc72e

Message:

Added support for partial submit strategy

Location:

libcfa/src/concurrency

Files:

• io.cfa (modified) (2 diffs)
• io/setup.cfa (modified) (1 diff)
• io/types.hfa (modified) (2 diffs)

libcfa/src/concurrency/io.cfa

@@ -514 +514 @@
         }
 
+        #define PARTIAL_SUBMIT 32
         static unsigned __collect_submitions( struct __io_data & ring ) {
                 /* paranoid */ verify( ring.submit_q.ready != 0p );
@@ -521 +522 @@
                 __u32 tail = *ring.submit_q.tail;
                 const __u32 mask = *ring.submit_q.mask;
+                #if defined(PARTIAL_SUBMIT)
+                        #if defined(LEADER_LOCK)
+                                #error PARTIAL_SUBMIT and LEADER_LOCK cannot co-exist
+                        #endif
+                        const __u32 cnt = ring.submit_q.ready_cnt > PARTIAL_SUBMIT ? PARTIAL_SUBMIT : ring.submit_q.ready_cnt;
+                        const __u32 offset = ring.submit_q.prev_ready;
+                        ring.submit_q.prev_ready += cnt;
+                #else
+                        const __u32 cnt = ring.submit_q.ready_cnt;
+                        const __u32 offset = 0;
+                #endif
 
                 // Go through the list of ready submissions
-                for( i; ring.submit_q.ready_cnt ) {
+                for( c; cnt ) {
+                        __u32 i = (offset + c) % ring.submit_q.ready_cnt;
+
                         // replace any submission with the sentinel, to consume it.
                         __u32 idx = __atomic_exchange_n( &ring.submit_q.ready[i], -1ul32, __ATOMIC_RELAXED);

libcfa/src/concurrency/io/setup.cfa

@@ -388 +388 @@
                                 sq.ready[i] = -1ul32;
                         }
+                        sq.prev_ready = 0;
                 }
                 else {
                         sq.ready_cnt = 0;
                         sq.ready = 0p;
+                        sq.prev_ready = 0;
                 }
 

libcfa/src/concurrency/io/types.hfa

@@ -23 +23 @@
       #include "bits/locks.hfa"
 
-        #define LEADER_LOCK
+        // #define LEADER_LOCK
         struct __leaderlock_t {
                 struct $thread * volatile value;        // ($thread) next_leader | (bool:1) is_locked
@@ -55 +55 @@
                 volatile __u32 * ready;
                 __u32 ready_cnt;
+                __u32 prev_ready;
 
                 #if defined(LEADER_LOCK)