Changeset dddb3dd0

Timestamp:

Mar 2, 2021, 1:58:12 PM (4 years ago)

Author:

Thierry Delisle <tdelisle@…>

Branches:

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

Children:

2cd784a

Parents:

6047b00

Message:

Changed io to use ring per kernel threads.

Location:

libcfa/src

Files:

• bits/defs.hfa (modified) (1 diff)
• concurrency/io.cfa (modified) (21 diffs)
• concurrency/io/call.cfa.in (modified) (5 diffs)
• concurrency/io/setup.cfa (modified) (10 diffs)
• concurrency/io/types.hfa (modified) (5 diffs)
• concurrency/iofwd.hfa (modified) (1 diff)
• concurrency/kernel.cfa (modified) (15 diffs)
• concurrency/kernel.hfa (modified) (4 diffs)
• concurrency/kernel/startup.cfa (modified) (11 diffs)
• concurrency/stats.cfa (modified) (4 diffs)
• concurrency/stats.hfa (modified) (1 diff)

libcfa/src/bits/defs.hfa

@@ -74 +74 @@
         #error unsupported architecture
 #endif
+
+#define CFA_IO_LAZY (1_l64u << 32_l64u)

libcfa/src/concurrency/io.cfa

@@ -32 +32 @@
         extern "C" {
                 #include <sys/syscall.h>
+                #include <sys/eventfd.h>
 
                 #include <linux/io_uring.h>
@@ -79 +80 @@
         };
 
-//=============================================================================================
-// I/O Syscall
-//=============================================================================================
-        static int __io_uring_enter( struct $io_context & ctx, unsigned to_submit, bool get ) {
-                __STATS__( false, io.calls.count++; )
-                bool need_sys_to_submit = false;
-                bool need_sys_to_complete = false;
-                unsigned flags = 0;
-
-                TO_SUBMIT:
-                if( to_submit > 0 ) {
-                        if( !(ctx.ring_flags & IORING_SETUP_SQPOLL) ) {
-                                need_sys_to_submit = true;
-                                break TO_SUBMIT;
-                        }
-                        if( (*ctx.sq.flags) & IORING_SQ_NEED_WAKEUP ) {
-                                need_sys_to_submit = true;
-                                flags |= IORING_ENTER_SQ_WAKEUP;
-                        }
-                }
-
-                if( get && !(ctx.ring_flags & IORING_SETUP_SQPOLL) ) {
-                        flags |= IORING_ENTER_GETEVENTS;
-                        if( (ctx.ring_flags & IORING_SETUP_IOPOLL) ) {
-                                need_sys_to_complete = true;
-                        }
-                }
-
-                int ret = 0;
-                if( need_sys_to_submit || need_sys_to_complete ) {
-                        __cfadbg_print_safe(io_core, "Kernel I/O : IO_URING enter %d %u %u\n", ctx.fd, to_submit, flags);
-                        __STATS__( false, io.calls.blocks++; )
-                        ret = syscall( __NR_io_uring_enter, ctx.fd, to_submit, 0, flags, (sigset_t *)0p, _NSIG / 8);
-                        __cfadbg_print_safe(io_core, "Kernel I/O : IO_URING %d returned %d\n", ctx.fd, ret);
-                }
-
-                // Memory barrier
-                __atomic_thread_fence( __ATOMIC_SEQ_CST );
-                return ret;
-        }
-
+        static $io_context * __ioarbiter_allocate( $io_arbiter & mutex this, processor *, __u32 idxs[], __u32 want );
+        static void __ioarbiter_submit( $io_arbiter & mutex this, $io_context * , __u32 idxs[], __u32 have, bool lazy );
+        static void __ioarbiter_flush ( $io_arbiter & mutex this, $io_context * );
+        static inline void __ioarbiter_notify( $io_context & ctx );
 //=============================================================================================
 // I/O Polling
@@ -126 +90 @@
         static inline __u32 __release_sqes( struct $io_context & );
 
-        static bool __drain_io( struct  $io_context & ctx ) {
-                unsigned to_submit = __flush( ctx );
-                int ret = __io_uring_enter( ctx, to_submit, true );
+        void __cfa_io_drain( processor * proc ) {
+                /* paranoid */ verify( ! __preemption_enabled() );
+                /* paranoid */ verify( proc );
+                /* paranoid */ verify( proc->io.ctx );
+
+                // Drain the queue
+                $io_context * ctx = proc->io.ctx;
+                unsigned head = *ctx->cq.head;
+                unsigned tail = *ctx->cq.tail;
+                const __u32 mask = *ctx->cq.mask;
+
+                __u32 count = tail - head;
+                __STATS__( false, io.calls.drain++; io.calls.completed += count; )
+
+                for(i; count) {
+                        unsigned idx = (head + i) & mask;
+                        volatile struct io_uring_cqe & cqe = ctx->cq.cqes[idx];
+
+                        /* paranoid */ verify(&cqe);
+
+                        struct io_future_t * future = (struct io_future_t *)(uintptr_t)cqe.user_data;
+                        __cfadbg_print_safe( io, "Kernel I/O : Syscall completed : cqe %p, result %d for %p\n", &cqe, cqe.res, future );
+
+                        fulfil( *future, cqe.res );
+                }
+
+                __cfadbg_print_safe(io, "Kernel I/O : %u completed\n", count);
+
+                // Mark to the kernel that the cqe has been seen
+                // Ensure that the kernel only sees the new value of the head index after the CQEs have been read.
+                __atomic_store_n( ctx->cq.head, head + count, __ATOMIC_SEQ_CST );
+
+                /* paranoid */ verify( ! __preemption_enabled() );
+
+                return;
+        }
+
+        void __cfa_io_flush( processor * proc ) {
+                /* paranoid */ verify( ! __preemption_enabled() );
+                /* paranoid */ verify( proc );
+                /* paranoid */ verify( proc->io.ctx );
+
+                $io_context & ctx = *proc->io.ctx;
+
+                if(!ctx.ext_sq.empty) {
+                        __ioarbiter_flush( *ctx.arbiter, &ctx );
+                }
+
+                __STATS__( true, io.calls.flush++; )
+                int ret = syscall( __NR_io_uring_enter, ctx.fd, ctx.sq.to_submit, 0, 0, (sigset_t *)0p, _NSIG / 8);
                 if( ret < 0 ) {
                         switch((int)errno) {
@@ -136 +147 @@
                                 // Update statistics
                                 __STATS__( false, io.calls.errors.busy ++; )
-                                return true;
-                                break;
+                                return;
                         default:
                                 abort( "KERNEL ERROR: IO_URING SYSCALL - (%d) %s\n", (int)errno, strerror(errno) );
@@ -143 +153 @@
                 }
 
-                // update statistics
-                if (to_submit > 0) {
-                        __STATS__( false, io.calls.submitted += ret; )
-                        /* paranoid */ verify( ctx.sq.to_submit <= *ctx.sq.num );
-
-                        /* paranoid */ verify( ctx.sq.to_submit >= ret );
-                        ctx.sq.to_submit -= ret;
-
-                        /* paranoid */ verify( ctx.sq.to_submit <= *ctx.sq.num );
-
-                        if(ret) {
-                                __cfadbg_print_safe(io, "Kernel I/O : %u submitted to io_uring\n", ret);
-                        }
-                }
+                __cfadbg_print_safe(io, "Kernel I/O : %u submitted to io_uring %d\n", ret, ctx.fd);
+                __STATS__( true, io.calls.submitted += ret; )
+                /* paranoid */ verify( ctx.sq.to_submit <= *ctx.sq.num );
+                /* paranoid */ verify( ctx.sq.to_submit >= ret );
+
+                ctx.sq.to_submit -= ret;
+
+                /* paranoid */ verify( ctx.sq.to_submit <= *ctx.sq.num );
 
                 // Release the consumed SQEs
                 __release_sqes( ctx );
 
-                // Drain the queue
-                unsigned head = *ctx.cq.head;
-                unsigned tail = *ctx.cq.tail;
-                const __u32 mask = *ctx.cq.mask;
-
-                // Nothing was new return 0
-                if (head == tail) {
-                        return ctx.sq.to_submit > 0;
-                }
-
-                __u32 count = tail - head;
-                /* paranoid */ verify( count != 0 );
-                __STATS__( false, io.calls.completed += count; )
-
-                for(i; count) {
-                        unsigned idx = (head + i) & mask;
-                        volatile struct io_uring_cqe & cqe = ctx.cq.cqes[idx];
-
-                        /* paranoid */ verify(&cqe);
-
-                        struct io_future_t * future = (struct io_future_t *)(uintptr_t)cqe.user_data;
-                        __cfadbg_print_safe( io, "Kernel I/O : Syscall completed : cqe %p, result %d for %p\n", &cqe, cqe.res, future );
-
-                        fulfil( *future, cqe.res );
-                }
-
-                if(count) {
-                        __cfadbg_print_safe(io, "Kernel I/O : %u completed\n", count);
-                }
-
-                // Mark to the kernel that the cqe has been seen
-                // Ensure that the kernel only sees the new value of the head index after the CQEs have been read.
-                __atomic_store_n( ctx.cq.head, head + count, __ATOMIC_SEQ_CST );
-
-                return count > 0 || to_submit > 0;
-        }
-
-        void main( $io_context & this ) {
-                __cfadbg_print_safe(io_core, "Kernel I/O : IO poller %d (%p) ready\n", this.fd, &this);
-
-                const int reset_cnt = 5;
-                int reset = reset_cnt;
-                // Then loop until we need to start
-                LOOP:
-                while() {
-                        waitfor( ^?{} : this) {
-                                break LOOP;
-                        }
-                        or else {}
-
-                        // Drain the io
-                        bool again = __drain_io( this );
-
-                        if(!again) reset--;
-
-                        // If we got something, just yield and check again
-                        if(reset > 1) {
-                                yield();
-                                continue LOOP;
-                        }
-
-                        // We alread failed to find completed entries a few time.
-                        if(reset == 1) {
-                                // Rearm the context so it can block
-                                // but don't block right away
-                                // we need to retry one last time in case
-                                // something completed *just now*
-                                __ioctx_prepare_block( this );
-                                continue LOOP;
-                        }
-
-                        __STATS__( false,
-                                io.poller.sleeps += 1;
-                        )
-                        __cfadbg_print_safe(io_core, "Kernel I/O : Parking io poller %d (%p)\n", this.fd, &this);
-
-                        // block this thread
-                        wait( this.sem );
-
-                        // restore counter
-                        reset = reset_cnt;
-                }
-
-                __cfadbg_print_safe(io_core, "Kernel I/O : Fast poller %d (%p) stopping\n", this.fd, &this);
+                /* paranoid */ verify( ! __preemption_enabled() );
+
+                ctx.proc->io.pending = false;
         }
 
@@ -266 +189 @@
 //         head and tail must be fully filled and shouldn't ever be touched again.
 //
-
-        static $io_context * __ioarbiter_allocate( $io_arbiter & mutex this, processor *, __u32 idxs[], __u32 want );
-        static void __ioarbiter_submit  ( $io_arbiter & mutex this, $io_context * , __u32 idxs[], __u32 have );
-        static void __ioarbiter_flush   ( $io_arbiter & mutex this, $io_context * );
-        static inline void __ioarbiter_notify( $io_context & ctx );
-
         //=============================================================================================
         // Allocation
@@ -278 +195 @@
                 struct io_uring_sqe * sqes = ctx->sq.sqes;
                 for(i; want) {
+                        __cfadbg_print_safe(io, "Kernel I/O : filling loop\n");
                         out_sqes[i] = &sqes[idxs[i]];
                 }
@@ -295 +213 @@
                 // copy all the indexes we want from the available list
                 for(i; want) {
+                        __cfadbg_print_safe(io, "Kernel I/O : allocating loop\n");
                         idxs[i] = sq.free_ring.array[(fhead + i) & mask];
                 }
@@ -315 +234 @@
                 disable_interrupts();
                 processor * proc = __cfaabi_tls.this_processor;
+                $io_context * ctx = proc->io.ctx;
                 /* paranoid */ verify( __cfaabi_tls.this_processor );
-                /* paranoid */ verify( proc->io.lock == false );
-
-                __atomic_store_n( &proc->io.lock, true, __ATOMIC_SEQ_CST );
-                $io_context * ctx = proc->io.ctx;
+                /* paranoid */ verify( ctx );
+
+                __cfadbg_print_safe(io, "Kernel I/O : attempting to fast allocation\n");
+
+                // We can proceed to the fast path
+                if( __alloc(ctx, idxs, want) ) {
+                        // Allocation was successful
+                        __STATS__( true, io.alloc.fast += 1; )
+                        enable_interrupts( __cfaabi_dbg_ctx );
+
+                        __cfadbg_print_safe(io, "Kernel I/O : fast allocation successful from ring %d\n", ctx->fd);
+
+                        __fill( sqes, want, idxs, ctx );
+                        return ctx;
+                }
+                // The fast path failed, fallback
+                __STATS__( true, io.alloc.fail += 1; )
+
+                // Fast path failed, fallback on arbitration
+                __STATS__( true, io.alloc.slow += 1; )
+                enable_interrupts( __cfaabi_dbg_ctx );
+
                 $io_arbiter * ioarb = proc->cltr->io.arbiter;
                 /* paranoid */ verify( ioarb );
 
-                // Can we proceed to the fast path
-                if(  ctx                                // We alreay have an instance?
-                &&  !ctx->revoked )             // Our instance is still valid?
-                {
-                        __cfadbg_print_safe(io, "Kernel I/O : attempting to fast allocation\n");
-
-                        // We can proceed to the fast path
-                        if( __alloc(ctx, idxs, want) ) {
-                                // Allocation was successful
-                                // Mark the instance as no longer in-use and re-enable interrupts
-                                __atomic_store_n( &proc->io.lock, false, __ATOMIC_RELEASE );
-                                __STATS__( true, io.alloc.fast += 1; )
-                                enable_interrupts( __cfaabi_dbg_ctx );
-
-                                __cfadbg_print_safe(io, "Kernel I/O : fast allocation successful\n");
-
-                                __fill( sqes, want, idxs, ctx );
-                                return ctx;
-                        }
-                        // The fast path failed, fallback
-                        __STATS__( true, io.alloc.fail += 1; )
-                }
-
-                // Fast path failed, fallback on arbitration
-                __atomic_store_n( &proc->io.lock, false, __ATOMIC_RELEASE );
-                __STATS__( true, io.alloc.slow += 1; )
-                enable_interrupts( __cfaabi_dbg_ctx );
-
                 __cfadbg_print_safe(io, "Kernel I/O : falling back on arbiter for allocation\n");
 
                 struct $io_context * ret = __ioarbiter_allocate(*ioarb, proc, idxs, want);
 
-                __cfadbg_print_safe(io, "Kernel I/O : slow allocation completed\n");
+                __cfadbg_print_safe(io, "Kernel I/O : slow allocation completed from ring %d\n", ret->fd);
 
                 __fill( sqes, want, idxs,ret );
@@ -364 +274 @@
         //=============================================================================================
         // submission
-        static inline void __submit( struct $io_context * ctx, __u32 idxs[], __u32 have) {
+        static inline void __submit( struct $io_context * ctx, __u32 idxs[], __u32 have, bool lazy) {
                 // We can proceed to the fast path
                 // Get the right objects
                 __sub_ring_t & sq = ctx->sq;
                 const __u32 mask  = *sq.mask;
-                __u32 tail = sq.kring.ready;
+                __u32 tail = *sq.kring.tail;
 
                 // Add the sqes to the array
                 for( i; have ) {
+                        __cfadbg_print_safe(io, "Kernel I/O : __submit loop\n");
                         sq.kring.array[ (tail + i) & mask ] = idxs[i];
                 }
 
                 // Make the sqes visible to the submitter
-                __atomic_store_n(&sq.kring.ready, tail + have, __ATOMIC_RELEASE);
-
-                // Make sure the poller is awake
-                __cfadbg_print_safe(io, "Kernel I/O : waking the poller\n");
-                post( ctx->sem );
-        }
-
-        void cfa_io_submit( struct $io_context * inctx, __u32 idxs[], __u32 have ) __attribute__((nonnull (1))) {
-                __cfadbg_print_safe(io, "Kernel I/O : attempting to submit %u\n", have);
+                __atomic_store_n(sq.kring.tail, tail + have, __ATOMIC_RELEASE);
+                sq.to_submit++;
+
+                ctx->proc->io.pending = true;
+                ctx->proc->io.dirty   = true;
+                if(sq.to_submit > 30 || !lazy) {
+                        __cfa_io_flush( ctx->proc );
+                }
+        }
+
+        void cfa_io_submit( struct $io_context * inctx, __u32 idxs[], __u32 have, bool lazy ) __attribute__((nonnull (1))) {
+                __cfadbg_print_safe(io, "Kernel I/O : attempting to submit %u (%s)\n", have, lazy ? "lazy" : "eager");
 
                 disable_interrupts();
                 processor * proc = __cfaabi_tls.this_processor;
+                $io_context * ctx = proc->io.ctx;
                 /* paranoid */ verify( __cfaabi_tls.this_processor );
-                /* paranoid */ verify( proc->io.lock == false );
-
-                __atomic_store_n( &proc->io.lock, true, __ATOMIC_SEQ_CST );
-                $io_context * ctx = proc->io.ctx;
+                /* paranoid */ verify( ctx );
 
                 // Can we proceed to the fast path
-                if(  ctx                                // We alreay have an instance?
-                &&  !ctx->revoked               // Our instance is still valid?
-                &&   ctx == inctx )             // We have the right instance?
+                if( ctx == inctx )              // We have the right instance?
                 {
-                        __submit(ctx, idxs, have);
+                        __submit(ctx, idxs, have, lazy);
 
                         // Mark the instance as no longer in-use, re-enable interrupts and return
-                        __atomic_store_n( &proc->io.lock, false, __ATOMIC_RELEASE );
                         __STATS__( true, io.submit.fast += 1; )
                         enable_interrupts( __cfaabi_dbg_ctx );
@@ -412 +321 @@
 
                 // Fast path failed, fallback on arbitration
-                __atomic_store_n( &proc->io.lock, false, __ATOMIC_RELEASE );
                 __STATS__( true, io.submit.slow += 1; )
                 enable_interrupts( __cfaabi_dbg_ctx );
@@ -418 +326 @@
                 __cfadbg_print_safe(io, "Kernel I/O : falling back on arbiter for submission\n");
 
-                __ioarbiter_submit(*inctx->arbiter, inctx, idxs, have);
+                __ioarbiter_submit(*inctx->arbiter, inctx, idxs, have, lazy);
         }
 
         //=============================================================================================
         // Flushing
-        static unsigned __flush( struct $io_context & ctx ) {
-                // First check for external
-                if( !__atomic_load_n(&ctx.ext_sq.empty, __ATOMIC_SEQ_CST) ) {
-                        // We have external submissions, delegate to the arbiter
-                        __ioarbiter_flush( *ctx.arbiter, &ctx );
-                }
-
-                __u32 tail  = *ctx.sq.kring.tail;
-                __u32 ready = ctx.sq.kring.ready;
-
-                /* paranoid */ verify( ctx.sq.to_submit <= *ctx.sq.num );
-                ctx.sq.to_submit += (ready - tail);
-                /* paranoid */ verify( ctx.sq.to_submit <= *ctx.sq.num );
-
-                if(ctx.sq.to_submit) {
-                        __cfadbg_print_safe(io, "Kernel I/O : %u ready to submit\n", ctx.sq.to_submit);
-                }
-
-                __atomic_store_n(ctx.sq.kring.tail, ready, __ATOMIC_RELEASE);
-
-                return ctx.sq.to_submit;
-        }
-
-
         // Go through the ring's submit queue and release everything that has already been consumed
         // by io_uring
@@ -484 +368 @@
                 // go through the range and release the sqes
                 for( i; count ) {
+                        __cfadbg_print_safe(io, "Kernel I/O : release loop\n");
                         __u32 idx = ctx.sq.kring.array[ (phead + i) & mask ];
                         ctx.sq.free_ring.array[ (ftail + i) & mask ] = idx;
@@ -499 +384 @@
 // I/O Arbiter
 //=============================================================================================
-        static inline void __revoke( $io_arbiter & this, $io_context * ctx ) {
-                if(ctx->revoked) return;
-
-                /* paranoid */ verify( ctx->proc );
-                remove( this.assigned, *ctx );
-
-                // Mark as revoked
-                __atomic_store_n(&ctx->revoked, true, __ATOMIC_SEQ_CST);
-
-                // Wait for the processor to no longer use it
-                while(ctx->proc->io.lock) Pause();
-
-                // Remove the coupling with the processor
-                ctx->proc->io.ctx = 0p;
-                ctx->proc = 0p;
-
-                // add to available contexts
-                addHead( this.available, *ctx );
-        }
-
-        static inline void __assign( $io_arbiter & this, $io_context * ctx, processor * proc ) {
-                remove( this.available, *ctx );
-
-                ctx->revoked = false;
-                ctx->proc = proc;
-                __atomic_store_n(&proc->io.ctx, ctx, __ATOMIC_SEQ_CST);
-
-                // add to assigned contexts
-                addTail( this.assigned, *ctx );
-        }
-
         static $io_context * __ioarbiter_allocate( $io_arbiter & mutex this, processor * proc, __u32 idxs[], __u32 want ) {
                 __cfadbg_print_safe(io, "Kernel I/O : arbiter allocating\n");
-
-                SeqIter($io_context) iter;
-                $io_context & ci;
-                // Do we already have something available?
-                for( over( iter, this.available ); iter | ci;) {
-                        __cfadbg_print_safe(io, "Kernel I/O : attempting available context\n");
-
-                        $io_context * c = &ci;
-                        if(__alloc(c, idxs, want)) {
-                                __assign( this, c, proc);
-                                return c;
-                        }
-                }
-
-
-                // Otherwise, we have no choice but to revoke everyone to check if other instance have available data
-                for( over( iter, this.assigned ); iter | ci; ) {
-                        __cfadbg_print_safe(io, "Kernel I/O : revoking context for allocation\n");
-
-                        $io_context * c = &ci;
-                        __revoke( this, c );
-
-                        __STATS__( false, io.alloc.revoke += 1; )
-
-                        if(__alloc(c, idxs, want)) {
-                                __assign( this, c, proc);
-                                return c;
-                        }
-                }
-
-                __cfadbg_print_safe(io, "Kernel I/O : waiting for available resources\n");
 
                 __STATS__( false, io.alloc.block += 1; )
@@ -577 +400 @@
                 /* paranoid */ verify( ret );
 
-                __assign( this, this.pending.ctx, proc);
                 return this.pending.ctx;
+
         }
 
@@ -586 +409 @@
 
                 while( !is_empty(this.pending.blocked) ) {
+                        __cfadbg_print_safe(io, "Kernel I/O : notifying\n");
                         __u32 have = ctx->sq.free_ring.tail - ctx->sq.free_ring.head;
                         __u32 want = front( this.pending.blocked );
@@ -604 +428 @@
 
         // Simply append to the pending
-        static void __ioarbiter_submit( $io_arbiter & mutex this, $io_context * ctx, __u32 idxs[], __u32 have ) {
+        static void __ioarbiter_submit( $io_arbiter & mutex this, $io_context * ctx, __u32 idxs[], __u32 have, bool lazy ) {
                 __cfadbg_print_safe(io, "Kernel I/O : submitting %u from the arbiter to context %u\n", have, ctx->fd);
 
@@ -612 +436 @@
                 __atomic_store_n( &ctx->ext_sq.empty, false, __ATOMIC_SEQ_CST );
 
-                // Wake-up the poller
-                post( ctx->sem );
-
                 __cfadbg_print_safe(io, "Kernel I/O : waiting to submit %u\n", have);
 
@@ -621 +442 @@
 
                 // Submit our indexes
-                __submit(ctx, idxs, have);
+                __submit(ctx, idxs, have, lazy);
 
                 __cfadbg_print_safe(io, "Kernel I/O : %u submitted from arbiter\n", have);
@@ -630 +451 @@
 
                 __STATS__( false, io.flush.external += 1; )
-
-                __revoke( this, ctx );
 
                 __cfadbg_print_safe(io, "Kernel I/O : arbiter flushing\n");
@@ -643 +462 @@
                 ctx->ext_sq.empty = true;
         }
-
-        void __ioarbiter_register( $io_arbiter & mutex this, $io_context & ctx ) {
-                __cfadbg_print_safe(io, "Kernel I/O : registering new context\n");
-
-                ctx.arbiter = &this;
-
-                // add to available contexts
-                addHead( this.available, ctx );
-
-                // Check if this solves pending allocations
-                if(this.pending.flag) {
-                        __ioarbiter_notify( ctx );
-                }
-        }
-
-        void __ioarbiter_unregister( $io_arbiter & mutex this, $io_context & ctx ) {
-                /* paranoid */ verify( &this == ctx.arbiter );
-
-                __revoke( this, &ctx );
-
-                remove( this.available, ctx );
-        }
 #endif

libcfa/src/concurrency/io/call.cfa.in

@@ -75 +75 @@
 
         extern struct $io_context * cfa_io_allocate(struct io_uring_sqe * out_sqes[], __u32 out_idxs[], __u32 want)  __attribute__((nonnull (1,2)));
-        extern void cfa_io_submit( struct $io_context * in_ctx, __u32 in_idxs[], __u32 have ) __attribute__((nonnull (1,2)));
+        extern void cfa_io_submit( struct $io_context * in_ctx, __u32 in_idxs[], __u32 have, bool lazy ) __attribute__((nonnull (1,2)));
 #endif
 
@@ -185 +185 @@
                 return ', '.join(args_a)
 
-AsyncTemplate = """inline void async_{name}(io_future_t & future, {params}, int submit_flags) {{
+AsyncTemplate = """inline void async_{name}(io_future_t & future, {params}, __u64 submit_flags) {{
         #if !defined(CFA_HAVE_LINUX_IO_URING_H) || !defined(CFA_HAVE_IORING_OP_{op})
                 ssize_t res = {name}({args});
@@ -216 +216 @@
 
                 verify( sqe->user_data == (__u64)(uintptr_t)&future );
-                cfa_io_submit( ctx, &idx, 1 );
+                cfa_io_submit( ctx, &idx, 1, 0 != (submit_flags & CFA_IO_LAZY) );
         #endif
 }}"""
 
-SyncTemplate = """{ret} cfa_{name}({params}, int submit_flags) {{
+SyncTemplate = """{ret} cfa_{name}({params}, __u64 submit_flags) {{
         io_future_t future;
 
@@ -388 +388 @@
         if c.define:
                 print("""#if defined({define})
-        {ret} cfa_{name}({params}, int submit_flags);
+        {ret} cfa_{name}({params}, __u64 submit_flags);
 #endif""".format(define=c.define,ret=c.ret, name=c.name, params=c.params))
         else:
-                print("{ret} cfa_{name}({params}, int submit_flags);"
+                print("{ret} cfa_{name}({params}, __u64 submit_flags);"
                 .format(ret=c.ret, name=c.name, params=c.params))
 
@@ -399 +399 @@
         if c.define:
                 print("""#if defined({define})
-        void async_{name}(io_future_t & future, {params}, int submit_flags);
+        void async_{name}(io_future_t & future, {params}, __u64 submit_flags);
 #endif""".format(define=c.define,name=c.name, params=c.params))
         else:
-                print("void async_{name}(io_future_t & future, {params}, int submit_flags);"
+                print("void async_{name}(io_future_t & future, {params}, __u64 submit_flags);"
                 .format(name=c.name, params=c.params))
 print("\n")

libcfa/src/concurrency/io/setup.cfa

@@ -26 +26 @@
 
 #if !defined(CFA_HAVE_LINUX_IO_URING_H)
-        void __kernel_io_startup() {
-                // Nothing to do without io_uring
-        }
-
-        void __kernel_io_shutdown() {
-                // Nothing to do without io_uring
-        }
-
         void ?{}(io_context_params & this) {}
 
@@ -97 +89 @@
 
 //=============================================================================================
-// I/O Startup / Shutdown logic + Master Poller
-//=============================================================================================
-
-        // IO Master poller loop forward
-        static void * iopoll_loop( __attribute__((unused)) void * args );
-
-        static struct {
-                      pthread_t  thrd;    // pthread handle to io poller thread
-                      void *     stack;   // pthread stack for io poller thread
-                      int        epollfd; // file descriptor to the epoll instance
-                volatile     bool run;     // Whether or not to continue
-                volatile     bool stopped; // Whether the poller has finished running
-                volatile uint64_t epoch;   // Epoch used for memory reclamation
-        } iopoll;
-
-        void __kernel_io_startup(void) {
-                __cfadbg_print_safe(io_core, "Kernel : Creating EPOLL instance\n" );
-
-                iopoll.epollfd = epoll_create1(0);
-                if (iopoll.epollfd == -1) {
-                        abort( "internal error, epoll_create1\n");
-                }
-
-                __cfadbg_print_safe(io_core, "Kernel : Starting io poller thread\n" );
-
-                iopoll.stack   = __create_pthread( &iopoll.thrd, iopoll_loop, 0p );
-                iopoll.run     = true;
-                iopoll.stopped = false;
-                iopoll.epoch   = 0;
-        }
-
-        void __kernel_io_shutdown(void) {
-                // Notify the io poller thread of the shutdown
-                iopoll.run = false;
-                sigval val = { 1 };
-                pthread_sigqueue( iopoll.thrd, SIGUSR1, val );
-
-                // Wait for the io poller thread to finish
-
-                __destroy_pthread( iopoll.thrd, iopoll.stack, 0p );
-
-                int ret = close(iopoll.epollfd);
-                if (ret == -1) {
-                        abort( "internal error, close epoll\n");
-                }
-
-                // Io polling is now fully stopped
-
-                __cfadbg_print_safe(io_core, "Kernel : IO poller stopped\n" );
-        }
-
-        static void * iopoll_loop( __attribute__((unused)) void * args ) {
-                __processor_id_t id;
-                id.full_proc = false;
-                id.id = doregister(&id);
-                __cfaabi_tls.this_proc_id = &id;
-                __cfadbg_print_safe(io_core, "Kernel : IO poller thread starting\n" );
-
-                // Block signals to control when they arrive
-                sigset_t mask;
-                sigfillset(&mask);
-                if ( pthread_sigmask( SIG_BLOCK, &mask, 0p ) == -1 ) {
-                abort( "internal error, pthread_sigmask" );
-                }
-
-                sigdelset( &mask, SIGUSR1 );
-
-                // Create sufficient events
-                struct epoll_event events[10];
-                // Main loop
-                while( iopoll.run ) {
-                        __cfadbg_print_safe(io_core, "Kernel I/O - epoll : waiting on io_uring contexts\n");
-
-                        // increment the epoch to notify any deleters we are starting a new cycle
-                        __atomic_fetch_add(&iopoll.epoch, 1, __ATOMIC_SEQ_CST);
-
-                        // Wait for events
-                        int nfds = epoll_pwait( iopoll.epollfd, events, 10, -1, &mask );
-
-                        __cfadbg_print_safe(io_core, "Kernel I/O - epoll : %d io contexts events, waking up\n", nfds);
-
-                        // Check if an error occured
-                        if (nfds == -1) {
-                                if( errno == EINTR ) continue;
-                                abort( "internal error, pthread_sigmask" );
-                        }
-
-                        for(i; nfds) {
-                                $io_context * io_ctx = ($io_context *)(uintptr_t)events[i].data.u64;
-                                /* paranoid */ verify( io_ctx );
-                                __cfadbg_print_safe(io_core, "Kernel I/O - epoll : Unparking io poller %d (%p)\n", io_ctx->fd, io_ctx);
-                                #if !defined( __CFA_NO_STATISTICS__ )
-                                        __cfaabi_tls.this_stats = io_ctx->self.curr_cluster->stats;
-                                #endif
-
-                                eventfd_t v;
-                                eventfd_read(io_ctx->efd, &v);
-
-                                post( io_ctx->sem );
-                        }
-                }
-
-                __atomic_store_n(&iopoll.stopped, true, __ATOMIC_SEQ_CST);
-
-                __cfadbg_print_safe(io_core, "Kernel : IO poller thread stopping\n" );
-                unregister(&id);
-                return 0p;
-        }
-
-//=============================================================================================
 // I/O Context Constrution/Destruction
 //=============================================================================================
 
-        static void __io_uring_setup ( $io_context & this, const io_context_params & params_in );
+
+
+        static void __io_uring_setup ( $io_context & this, const io_context_params & params_in, int procfd );
         static void __io_uring_teardown( $io_context & this );
         static void __epoll_register($io_context & ctx);
@@ -217 +101 @@
         void __ioarbiter_unregister( $io_arbiter & mutex, $io_context & ctx );
 
-        void ?{}($io_context & this, struct cluster & cl) {
-                (this.self){ "IO Poller", cl };
+        void ?{}($io_context & this, processor * proc, struct cluster & cl) {
+                /* paranoid */ verify( cl.io.arbiter );
+                this.proc = proc;
+                this.arbiter = cl.io.arbiter;
                 this.ext_sq.empty = true;
-                this.revoked = true;
-                __io_uring_setup( this, cl.io.params );
+                (this.ext_sq.blocked){};
+                __io_uring_setup( this, cl.io.params, proc->idle );
                 __cfadbg_print_safe(io_core, "Kernel I/O : Created ring for io_context %u (%p)\n", this.fd, &this);
-
-                __epoll_register(this);
-
-                __ioarbiter_register(*cl.io.arbiter, this);
-
-                __thrd_start( this, main );
-                __cfadbg_print_safe(io_core, "Kernel I/O : Started poller thread for io_context %u\n", this.fd);
-        }
-
-        void ^?{}($io_context & mutex this) {
+        }
+
+        void ^?{}($io_context & this) {
                 __cfadbg_print_safe(io_core, "Kernel I/O : tearing down io_context %u\n", this.fd);
-
-                ^(this.self){};
-                __cfadbg_print_safe(io_core, "Kernel I/O : Stopped poller thread for io_context %u\n", this.fd);
-
-                __ioarbiter_unregister(*this.arbiter, this);
-
-                __epoll_unregister(this);
 
                 __io_uring_teardown( this );
@@ -246 +118 @@
         }
 
-        void ?{}(io_context & this, struct cluster & cl) {
-                // this.ctx = new(cl);
-                this.ctx = alloc();
-                (*this.ctx){ cl };
-
-                __cfadbg_print_safe(io_core, "Kernel I/O : io_context %u ready\n", this.ctx->fd);
-        }
-
-        void ^?{}(io_context & this) {
-                post( this.ctx->sem );
-
-                delete(this.ctx);
-        }
-
         extern void __disable_interrupts_hard();
         extern void __enable_interrupts_hard();
 
-        static void __io_uring_setup( $io_context & this, const io_context_params & params_in ) {
+        static void __io_uring_setup( $io_context & this, const io_context_params & params_in, int procfd ) {
                 // Step 1 : call to setup
                 struct io_uring_params params;
@@ -339 +197 @@
                 sq.dropped     = (         __u32 *)(((intptr_t)sq.ring_ptr) + params.sq_off.dropped);
 
-                sq.kring.ready = 0;
                 sq.kring.released = 0;
 
@@ -362 +219 @@
                 // io_uring_register is so f*cking slow on some machine that it
                 // will never succeed if preemption isn't hard blocked
+                __cfadbg_print_safe(io_core, "Kernel I/O : registering %d for completion with ring %d\n", procfd, fd);
+
                 __disable_interrupts_hard();
 
-                int efd = eventfd(0, 0);
-                if (efd < 0) {
-                        abort("KERNEL ERROR: IO_URING EVENTFD - %s\n", strerror(errno));
-                }
-
-                int ret = syscall( __NR_io_uring_register, fd, IORING_REGISTER_EVENTFD, &efd, 1);
+                int ret = syscall( __NR_io_uring_register, fd, IORING_REGISTER_EVENTFD, &procfd, 1);
                 if (ret < 0) {
                         abort("KERNEL ERROR: IO_URING EVENTFD REGISTER - %s\n", strerror(errno));
@@ -375 +229 @@
 
                 __enable_interrupts_hard();
+
+                __cfadbg_print_safe(io_core, "Kernel I/O : registered %d for completion with ring %d\n", procfd, fd);
 
                 // some paranoid checks
@@ -390 +246 @@
                 this.ring_flags = 0;
                 this.fd         = fd;
-                this.efd        = efd;
         }
 
@@ -411 +266 @@
                 // close the file descriptor
                 close(this.fd);
-                close(this.efd);
 
                 free( this.sq.free_ring.array ); // Maybe null, doesn't matter
         }
 
+        void __cfa_io_start( processor * proc ) {
+                proc->io.ctx = alloc();
+                (*proc->io.ctx){proc, *proc->cltr};
+        }
+        void __cfa_io_stop ( processor * proc ) {
+                ^(*proc->io.ctx){};
+                free(proc->io.ctx);
+        }
+
 //=============================================================================================
 // I/O Context Sleep
 //=============================================================================================
-        static inline void __epoll_ctl($io_context & ctx, int op, const char * error) {
-                struct epoll_event ev;
-                ev.events = EPOLLIN | EPOLLONESHOT;
-                ev.data.u64 = (__u64)&ctx;
-                int ret = epoll_ctl(iopoll.epollfd, op, ctx.efd, &ev);
-                if (ret < 0) {
-                        abort( "KERNEL ERROR: EPOLL %s - (%d) %s\n", error, (int)errno, strerror(errno) );
-                }
-        }
-
-        static void __epoll_register($io_context & ctx) {
-                __epoll_ctl(ctx, EPOLL_CTL_ADD, "ADD");
-        }
-
-        static void __epoll_unregister($io_context & ctx) {
-                // Read the current epoch so we know when to stop
-                size_t curr = __atomic_load_n(&iopoll.epoch, __ATOMIC_SEQ_CST);
-
-                // Remove the fd from the iopoller
-                __epoll_ctl(ctx, EPOLL_CTL_DEL, "REMOVE");
-
-                // Notify the io poller thread of the shutdown
-                iopoll.run = false;
-                sigval val = { 1 };
-                pthread_sigqueue( iopoll.thrd, SIGUSR1, val );
-
-                // Make sure all this is done
-                __atomic_thread_fence(__ATOMIC_SEQ_CST);
-
-                // Wait for the next epoch
-                while(curr == iopoll.epoch && !iopoll.stopped) Pause();
-        }
-
-        void __ioctx_prepare_block($io_context & ctx) {
-                __cfadbg_print_safe(io_core, "Kernel I/O - epoll : Re-arming io poller %d (%p)\n", ctx.fd, &ctx);
-                __epoll_ctl(ctx, EPOLL_CTL_MOD, "REARM");
-        }
+        // static inline void __epoll_ctl($io_context & ctx, int op, const char * error) {
+        //      struct epoll_event ev;
+        //      ev.events = EPOLLIN | EPOLLONESHOT;
+        //      ev.data.u64 = (__u64)&ctx;
+        //      int ret = epoll_ctl(iopoll.epollfd, op, ctx.efd, &ev);
+        //      if (ret < 0) {
+        //              abort( "KERNEL ERROR: EPOLL %s - (%d) %s\n", error, (int)errno, strerror(errno) );
+        //      }
+        // }
+
+        // static void __epoll_register($io_context & ctx) {
+        //      __epoll_ctl(ctx, EPOLL_CTL_ADD, "ADD");
+        // }
+
+        // static void __epoll_unregister($io_context & ctx) {
+        //      // Read the current epoch so we know when to stop
+        //      size_t curr = __atomic_load_n(&iopoll.epoch, __ATOMIC_SEQ_CST);
+
+        //      // Remove the fd from the iopoller
+        //      __epoll_ctl(ctx, EPOLL_CTL_DEL, "REMOVE");
+
+        //      // Notify the io poller thread of the shutdown
+        //      iopoll.run = false;
+        //      sigval val = { 1 };
+        //      pthread_sigqueue( iopoll.thrd, SIGUSR1, val );
+
+        //      // Make sure all this is done
+        //      __atomic_thread_fence(__ATOMIC_SEQ_CST);
+
+        //      // Wait for the next epoch
+        //      while(curr == iopoll.epoch && !iopoll.stopped) Pause();
+        // }
+
+        // void __ioctx_prepare_block($io_context & ctx) {
+        //      __cfadbg_print_safe(io_core, "Kernel I/O - epoll : Re-arming io poller %d (%p)\n", ctx.fd, &ctx);
+        //      __epoll_ctl(ctx, EPOLL_CTL_MOD, "REARM");
+        // }
 
 
@@ -466 +329 @@
 
         void ^?{}( $io_arbiter & mutex this ) {
-                /* paranoid */ verify( empty(this.assigned) );
-                /* paranoid */ verify( empty(this.available) );
+                // /* paranoid */ verify( empty(this.assigned) );
+                // /* paranoid */ verify( empty(this.available) );
                 /* paranoid */ verify( is_empty(this.pending.blocked) );
         }

libcfa/src/concurrency/io/types.hfa

@@ -38 +38 @@
                         volatile __u32 * head;   // one passed last index consumed by the kernel
                         volatile __u32 * tail;   // one passed last index visible to the kernel
-                        volatile __u32 ready;    // one passed last index added to array ()
                         volatile __u32 released; // one passed last index released back to the free list
 
@@ -97 +96 @@
 
         struct __attribute__((aligned(128))) $io_context {
-                inline Seqable;
-
-                volatile bool revoked;
+                $io_arbiter * arbiter;
                 processor * proc;
-
-                $io_arbiter * arbiter;
 
                 struct {
@@ -113 +108 @@
                 __u32 ring_flags;
                 int fd;
-                int efd;
-
-                single_sem sem;
-                $thread self;
         };
-
-        void main( $io_context & this );
-        static inline $thread  * get_thread ( $io_context & this ) __attribute__((const)) { return &this.self; }
-        static inline $monitor * get_monitor( $io_context & this ) __attribute__((const)) { return &this.self.self_mon; }
-        static inline $io_context *& Back( $io_context * n ) { return ($io_context *)Back( (Seqable *)n ); }
-        static inline $io_context *& Next( $io_context * n ) { return ($io_context *)Next( (Colable *)n ); }
-        void ^?{}( $io_context & mutex this );
 
         monitor __attribute__((aligned(128))) $io_arbiter {
@@ -132 +116 @@
                         volatile bool flag;
                 } pending;
-
-                Sequence($io_context) assigned;
-
-                Sequence($io_context) available;
         };
 
@@ -167 +147 @@
         #endif
 
-        void __ioctx_prepare_block($io_context & ctx);
+        // void __ioctx_prepare_block($io_context & ctx);
 #endif
 

libcfa/src/concurrency/iofwd.hfa

@@ -59 +59 @@
 // underlying calls
 extern struct $io_context * cfa_io_allocate(struct io_uring_sqe * out_sqes[], __u32 out_idxs[], __u32 want)  __attribute__((nonnull (1,2)));
-extern void cfa_io_submit( struct $io_context * in_ctx, __u32 in_idxs[], __u32 have ) __attribute__((nonnull (1,2)));
+extern void cfa_io_submit( struct $io_context * in_ctx, __u32 in_idxs[], __u32 have, bool lazy ) __attribute__((nonnull (1,2)));
 
 //----------
 // synchronous calls
 #if defined(CFA_HAVE_PREADV2)
-        extern ssize_t cfa_preadv2(int fd, const struct iovec *iov, int iovcnt, off_t offset, int flags, int submit_flags);
+        extern ssize_t cfa_preadv2(int fd, const struct iovec *iov, int iovcnt, off_t offset, int flags, __u64 submit_flags);
 #endif
 #if defined(CFA_HAVE_PWRITEV2)
-        extern ssize_t cfa_pwritev2(int fd, const struct iovec *iov, int iovcnt, off_t offset, int flags, int submit_flags);
+        extern ssize_t cfa_pwritev2(int fd, const struct iovec *iov, int iovcnt, off_t offset, int flags, __u64 submit_flags);
 #endif
-extern int cfa_fsync(int fd, int submit_flags);
-extern int cfa_epoll_ctl(int epfd, int op, int fd, struct epoll_event *event, int submit_flags);
-extern int cfa_sync_file_range(int fd, off64_t offset, off64_t nbytes, unsigned int flags, int submit_flags);
-extern  ssize_t cfa_sendmsg(int sockfd, const struct msghdr *msg, int flags, int submit_flags);
-extern ssize_t cfa_recvmsg(int sockfd, struct msghdr *msg, int flags, int submit_flags);
-extern ssize_t cfa_send(int sockfd, const void *buf, size_t len, int flags, int submit_flags);
-extern ssize_t cfa_recv(int sockfd, void *buf, size_t len, int flags, int submit_flags);
-extern int cfa_accept4(int sockfd, struct sockaddr *addr, socklen_t *addrlen, int flags, int submit_flags);
-extern int cfa_connect(int sockfd, const struct sockaddr *addr, socklen_t addrlen, int submit_flags);
-extern int cfa_fallocate(int fd, int mode, off_t offset, off_t len, int submit_flags);
-extern int cfa_posix_fadvise(int fd, off_t offset, off_t len, int advice, int submit_flags);
-extern int cfa_madvise(void *addr, size_t length, int advice, int submit_flags);
-extern int cfa_openat(int dirfd, const char *pathname, int flags, mode_t mode, int submit_flags);
+extern int cfa_fsync(int fd, __u64 submit_flags);
+extern int cfa_epoll_ctl(int epfd, int op, int fd, struct epoll_event *event, __u64 submit_flags);
+extern int cfa_sync_file_range(int fd, off64_t offset, off64_t nbytes, unsigned int flags, __u64 submit_flags);
+extern  ssize_t cfa_sendmsg(int sockfd, const struct msghdr *msg, int flags, __u64 submit_flags);
+extern ssize_t cfa_recvmsg(int sockfd, struct msghdr *msg, int flags, __u64 submit_flags);
+extern ssize_t cfa_send(int sockfd, const void *buf, size_t len, int flags, __u64 submit_flags);
+extern ssize_t cfa_recv(int sockfd, void *buf, size_t len, int flags, __u64 submit_flags);
+extern int cfa_accept4(int sockfd, struct sockaddr *addr, socklen_t *addrlen, int flags, __u64 submit_flags);
+extern int cfa_connect(int sockfd, const struct sockaddr *addr, socklen_t addrlen, __u64 submit_flags);
+extern int cfa_fallocate(int fd, int mode, off_t offset, off_t len, __u64 submit_flags);
+extern int cfa_posix_fadvise(int fd, off_t offset, off_t len, int advice, __u64 submit_flags);
+extern int cfa_madvise(void *addr, size_t length, int advice, __u64 submit_flags);
+extern int cfa_openat(int dirfd, const char *pathname, int flags, mode_t mode, __u64 submit_flags);
 #if defined(CFA_HAVE_OPENAT2)
-        extern int cfa_openat2(int dirfd, const char *pathname, struct open_how * how, size_t size, int submit_flags);
+        extern int cfa_openat2(int dirfd, const char *pathname, struct open_how * how, size_t size, __u64 submit_flags);
 #endif
-extern int cfa_close(int fd, int submit_flags);
+extern int cfa_close(int fd, __u64 submit_flags);
 #if defined(CFA_HAVE_STATX)
-        extern int cfa_statx(int dirfd, const char *pathname, int flags, unsigned int mask, struct statx *statxbuf, int submit_flags);
+        extern int cfa_statx(int dirfd, const char *pathname, int flags, unsigned int mask, struct statx *statxbuf, __u64 submit_flags);
 #endif
-extern ssize_t cfa_read(int fd, void * buf, size_t count, int submit_flags);
-extern ssize_t cfa_write(int fd, void * buf, size_t count, int submit_flags);
-extern ssize_t cfa_splice(int fd_in, loff_t *off_in, int fd_out, loff_t *off_out, size_t len, unsigned int flags, int submit_flags);
-extern ssize_t cfa_tee(int fd_in, int fd_out, size_t len, unsigned int flags, int submit_flags);
+extern ssize_t cfa_read(int fd, void * buf, size_t count, __u64 submit_flags);
+extern ssize_t cfa_write(int fd, void * buf, size_t count, __u64 submit_flags);
+extern ssize_t cfa_splice(int fd_in, loff_t *off_in, int fd_out, loff_t *off_out, size_t len, unsigned int flags, __u64 submit_flags);
+extern ssize_t cfa_tee(int fd_in, int fd_out, size_t len, unsigned int flags, __u64 submit_flags);
 
 //----------
 // asynchronous calls
 #if defined(CFA_HAVE_PREADV2)
-        extern void async_preadv2(io_future_t & future, int fd, const struct iovec *iov, int iovcnt, off_t offset, int flags, int submit_flags);
+        extern void async_preadv2(io_future_t & future, int fd, const struct iovec *iov, int iovcnt, off_t offset, int flags, __u64 submit_flags);
 #endif
 #if defined(CFA_HAVE_PWRITEV2)
-        extern void async_pwritev2(io_future_t & future, int fd, const struct iovec *iov, int iovcnt, off_t offset, int flags, int submit_flags);
+        extern void async_pwritev2(io_future_t & future, int fd, const struct iovec *iov, int iovcnt, off_t offset, int flags, __u64 submit_flags);
 #endif
-extern void async_fsync(io_future_t & future, int fd, int submit_flags);
-extern void async_epoll_ctl(io_future_t & future, int epfd, int op, int fd, struct epoll_event *event, int submit_flags);
-extern void async_sync_file_range(io_future_t & future, int fd, off64_t offset, off64_t nbytes, unsigned int flags, int submit_flags);
-extern void async_sendmsg(io_future_t & future, int sockfd, const struct msghdr *msg, int flags, int submit_flags);
-extern void async_recvmsg(io_future_t & future, int sockfd, struct msghdr *msg, int flags, int submit_flags);
-extern void async_send(io_future_t & future, int sockfd, const void *buf, size_t len, int flags, int submit_flags);
-extern void async_recv(io_future_t & future, int sockfd, void *buf, size_t len, int flags, int submit_flags);
-extern void async_accept4(io_future_t & future, int sockfd, struct sockaddr *addr, socklen_t *addrlen, int flags, int submit_flags);
-extern void async_connect(io_future_t & future, int sockfd, const struct sockaddr *addr, socklen_t addrlen, int submit_flags);
-extern void async_fallocate(io_future_t & future, int fd, int mode, off_t offset, off_t len, int submit_flags);
-extern void async_posix_fadvise(io_future_t & future, int fd, off_t offset, off_t len, int advice, int submit_flags);
-extern void async_madvise(io_future_t & future, void *addr, size_t length, int advice, int submit_flags);
-extern void async_openat(io_future_t & future, int dirfd, const char *pathname, int flags, mode_t mode, int submit_flags);
+extern void async_fsync(io_future_t & future, int fd, __u64 submit_flags);
+extern void async_epoll_ctl(io_future_t & future, int epfd, int op, int fd, struct epoll_event *event, __u64 submit_flags);
+extern void async_sync_file_range(io_future_t & future, int fd, off64_t offset, off64_t nbytes, unsigned int flags, __u64 submit_flags);
+extern void async_sendmsg(io_future_t & future, int sockfd, const struct msghdr *msg, int flags, __u64 submit_flags);
+extern void async_recvmsg(io_future_t & future, int sockfd, struct msghdr *msg, int flags, __u64 submit_flags);
+extern void async_send(io_future_t & future, int sockfd, const void *buf, size_t len, int flags, __u64 submit_flags);
+extern void async_recv(io_future_t & future, int sockfd, void *buf, size_t len, int flags, __u64 submit_flags);
+extern void async_accept4(io_future_t & future, int sockfd, struct sockaddr *addr, socklen_t *addrlen, int flags, __u64 submit_flags);
+extern void async_connect(io_future_t & future, int sockfd, const struct sockaddr *addr, socklen_t addrlen, __u64 submit_flags);
+extern void async_fallocate(io_future_t & future, int fd, int mode, off_t offset, off_t len, __u64 submit_flags);
+extern void async_posix_fadvise(io_future_t & future, int fd, off_t offset, off_t len, int advice, __u64 submit_flags);
+extern void async_madvise(io_future_t & future, void *addr, size_t length, int advice, __u64 submit_flags);
+extern void async_openat(io_future_t & future, int dirfd, const char *pathname, int flags, mode_t mode, __u64 submit_flags);
 #if defined(CFA_HAVE_OPENAT2)
-        extern void async_openat2(io_future_t & future, int dirfd, const char *pathname, struct open_how * how, size_t size, int submit_flags);
+        extern void async_openat2(io_future_t & future, int dirfd, const char *pathname, struct open_how * how, size_t size, __u64 submit_flags);
 #endif
-extern void async_close(io_future_t & future, int fd, int submit_flags);
+extern void async_close(io_future_t & future, int fd, __u64 submit_flags);
 #if defined(CFA_HAVE_STATX)
-        extern void async_statx(io_future_t & future, int dirfd, const char *pathname, int flags, unsigned int mask, struct statx *statxbuf, int submit_flags);
+        extern void async_statx(io_future_t & future, int dirfd, const char *pathname, int flags, unsigned int mask, struct statx *statxbuf, __u64 submit_flags);
 #endif
-void async_read(io_future_t & future, int fd, void * buf, size_t count, int submit_flags);
-extern void async_write(io_future_t & future, int fd, void * buf, size_t count, int submit_flags);
-extern void async_splice(io_future_t & future, int fd_in, loff_t *off_in, int fd_out, loff_t *off_out, size_t len, unsigned int flags, int submit_flags);
-extern void async_tee(io_future_t & future, int fd_in, int fd_out, size_t len, unsigned int flags, int submit_flags);
+void async_read(io_future_t & future, int fd, void * buf, size_t count, __u64 submit_flags);
+extern void async_write(io_future_t & future, int fd, void * buf, size_t count, __u64 submit_flags);
+extern void async_splice(io_future_t & future, int fd_in, loff_t *off_in, int fd_out, loff_t *off_out, size_t len, unsigned int flags, __u64 submit_flags);
+extern void async_tee(io_future_t & future, int fd_in, int fd_out, size_t len, unsigned int flags, __u64 submit_flags);
 
 

libcfa/src/concurrency/kernel.cfa

@@ -22 +22 @@
 #include <signal.h>
 #include <unistd.h>
+extern "C" {
+        #include <sys/eventfd.h>
+}
 
 //CFA Includes
@@ -109 +112 @@
 static void __run_thread(processor * this, $thread * dst);
 static void __wake_one(cluster * cltr);
-static void wait(__bin_sem_t & this);
 
 static void push  (__cluster_idles & idles, processor & proc);
@@ -115 +117 @@
 static [unsigned idle, unsigned total, * processor] query( & __cluster_idles idles );
 
+extern void __cfa_io_start( processor * );
+extern void __cfa_io_drain( processor * );
+extern void __cfa_io_flush( processor * );
+extern void __cfa_io_stop ( processor * );
+static inline void __maybe_io_drain( processor * );
+
+extern void __disable_interrupts_hard();
+extern void __enable_interrupts_hard();
 
 //=============================================================================================
@@ -130 +140 @@
         verify(this);
 
+        __cfa_io_start( this );
+
         __cfadbg_print_safe(runtime_core, "Kernel : core %p starting\n", this);
         #if !defined(__CFA_NO_STATISTICS__)
@@ -151 +163 @@
                 MAIN_LOOP:
                 for() {
+                        // Check if there is pending io
+                        __maybe_io_drain( this );
+
                         // Try to get the next thread
                         readyThread = __next_thread( this->cltr );
 
                         if( !readyThread ) {
+                                __cfa_io_flush( this );
                                 readyThread = __next_thread_slow( this->cltr );
                         }
@@ -190 +206 @@
                                 #endif
 
-                                wait( this->idle );
+                                __cfadbg_print_safe(runtime_core, "Kernel : core %p waiting on eventfd %d\n", this, this->idle);
+
+                                __disable_interrupts_hard();
+                                eventfd_t val;
+                                eventfd_read( this->idle, &val );
+                                __enable_interrupts_hard();
 
                                 #if !defined(__CFA_NO_STATISTICS__)
@@ -206 +227 @@
 
                         /* paranoid */ verify( readyThread );
+
+                        // Reset io dirty bit
+                        this->io.dirty = false;
 
                         // We found a thread run it
@@ -220 +244 @@
                                 }
                         #endif
+
+                        if(this->io.pending && !this->io.dirty) {
+                                __cfa_io_flush( this );
+                        }
                 }
 
@@ -225 +253 @@
         }
 
+        __cfa_io_stop( this );
+
         post( this->terminated );
+
 
         if(this == mainProcessor) {
@@ -248 +279 @@
         /* paranoid */ verifyf( thrd_dst->link.next == 0p, "Expected null got %p", thrd_dst->link.next );
         __builtin_prefetch( thrd_dst->context.SP );
+
+        __cfadbg_print_safe(runtime_core, "Kernel : core %p running thread %p (%s)\n", this, thrd_dst, thrd_dst->self_cor.name);
 
         $coroutine * proc_cor = get_coroutine(this->runner);
@@ -330 +363 @@
         // Just before returning to the processor, set the processor coroutine to active
         proc_cor->state = Active;
+
+        __cfadbg_print_safe(runtime_core, "Kernel : core %p finished running thread %p\n", this, thrd_dst);
 
         /* paranoid */ verify( ! __preemption_enabled() );
@@ -549 +584 @@
 // Kernel Idle Sleep
 //=============================================================================================
-extern "C" {
-        char * strerror(int);
-}
-#define CHECKED(x) { int err = x; if( err != 0 ) abort("KERNEL ERROR: Operation \"" #x "\" return error %d - %s\n", err, strerror(err)); }
-
-static void wait(__bin_sem_t & this) with( this ) {
-        verify(__cfaabi_dbg_in_kernel());
-        CHECKED( pthread_mutex_lock(&lock) );
-                while(val < 1) {
-                        pthread_cond_wait(&cond, &lock);
-                }
-                val -= 1;
-        CHECKED( pthread_mutex_unlock(&lock) );
-}
-
-static bool post(__bin_sem_t & this) with( this ) {
-        bool needs_signal = false;
-
-        CHECKED( pthread_mutex_lock(&lock) );
-                if(val < 1) {
-                        val += 1;
-                        pthread_cond_signal(&cond);
-                        needs_signal = true;
-                }
-        CHECKED( pthread_mutex_unlock(&lock) );
-
-        return needs_signal;
-}
-
-#undef CHECKED
-
 // Wake a thread from the front if there are any
 static void __wake_one(cluster * this) {
@@ -595 +599 @@
 
         // We found a processor, wake it up
-        post( p->idle );
+        eventfd_t val;
+        val = 1;
+        eventfd_write( p->idle, val );
 
         #if !defined(__CFA_NO_STATISTICS__)
@@ -613 +619 @@
         disable_interrupts();
                 /* paranoid */ verify( ! __preemption_enabled() );
-                post( this->idle );
+                eventfd_t val;
+                val = 1;
+                eventfd_read( this->idle, &val );
         enable_interrupts( __cfaabi_dbg_ctx );
 }
@@ -696 +704 @@
 // Kernel Utilities
 //=============================================================================================
+#if defined(CFA_HAVE_LINUX_IO_URING_H)
+#include "io/types.hfa"
+#endif
+
+static inline void __maybe_io_drain( processor * proc ) {
+        #if defined(CFA_HAVE_LINUX_IO_URING_H)
+                __cfadbg_print_safe(runtime_core, "Kernel : core %p checking io for ring %d\n", proc, proc->io.ctx->fd);
+
+                // Check if we should drain the queue
+                $io_context * ctx = proc->io.ctx;
+                unsigned head = *ctx->cq.head;
+                unsigned tail = *ctx->cq.tail;
+                if(head != tail) __cfa_io_drain( proc );
+        #endif
+}
+
 //-----------------------------------------------------------------------------
 // Debug

libcfa/src/concurrency/kernel.hfa

@@ -28 +28 @@
 }
 
-//-----------------------------------------------------------------------------
-// Underlying Locks
 #ifdef __CFA_WITH_VERIFY__
         extern bool __cfaabi_dbg_in_kernel();
 #endif
-
-struct __bin_sem_t {
-        pthread_mutex_t         lock;
-        pthread_cond_t          cond;
-        int                     val;
-};
 
 //-----------------------------------------------------------------------------
@@ -52 +44 @@
 void  ?{}(io_context_params & this);
 
-struct io_context {
-        $io_context * ctx;
-        cluster * cltr;
-};
-void  ?{}(io_context & this, struct cluster & cl);
-void ^?{}(io_context & this);
-
 //-----------------------------------------------------------------------------
 // Processor
@@ -98 +83 @@
 
         struct {
-                $io_context * volatile ctx;
-                volatile bool lock;
+                $io_context * ctx;
+                bool pending;
+                bool dirty;
         } io;
 
@@ -110 +96 @@
 
         // Idle lock (kernel semaphore)
-        __bin_sem_t idle;
+        int idle;
 
         // Termination synchronisation (user semaphore)

libcfa/src/concurrency/kernel/startup.cfa

@@ -22 +22 @@
 extern "C" {
       #include <limits.h>       // PTHREAD_STACK_MIN
+        #include <sys/eventfd.h>  // eventfd
       #include <sys/mman.h>     // mprotect
       #include <sys/resource.h> // getrlimit
@@ -80 +81 @@
 static void ?{}(processorCtx_t & this) {}
 static void ?{}(processorCtx_t & this, processor * proc, current_stack_info_t * info);
-static void ?{}(__bin_sem_t & this);
-static void ^?{}(__bin_sem_t & this);
 
 #if defined(__CFA_WITH_VERIFY__)
@@ -91 +90 @@
 extern void __kernel_alarm_startup(void);
 extern void __kernel_alarm_shutdown(void);
-extern void __kernel_io_startup (void);
-extern void __kernel_io_shutdown(void);
 
 //-----------------------------------------------------------------------------
@@ -104 +101 @@
 KERNEL_STORAGE($thread,              mainThread);
 KERNEL_STORAGE(__stack_t,            mainThreadCtx);
-KERNEL_STORAGE(io_context,           mainIoContext);
 KERNEL_STORAGE(__scheduler_RWLock_t, __scheduler_lock);
 #if !defined(__CFA_NO_STATISTICS__)
@@ -200 +196 @@
 
         void ?{}(processor & this) with( this ) {
-                ( this.idle ){};
                 ( this.terminated ){};
                 ( this.runner ){};
@@ -228 +223 @@
         __kernel_alarm_startup();
 
-        // Start IO
-        __kernel_io_startup();
-
-        io_context * mainio = (io_context *)&storage_mainIoContext;
-        (*mainio){ *mainCluster };
-
         // Add the main thread to the ready queue
         // once resume is called on mainProcessor->runner the mainThread needs to be scheduled like any normal thread
@@ -255 +244 @@
 
 static void __kernel_shutdown(void) {
-        //Before we start shutting things down, wait for systems that need threading to shutdown
-        io_context * mainio = (io_context *)&storage_mainIoContext;
-        ^(*mainio){};
-
         /* paranoid */ verify( __preemption_enabled() );
         disable_interrupts();
@@ -276 +261 @@
         // Disable preemption
         __kernel_alarm_shutdown();
-
-        // Stop IO
-        __kernel_io_shutdown();
 
         // Destroy the main processor and its context in reverse order of construction
@@ -479 +461 @@
 
         this.io.ctx = 0p;
-        this.io.lock = false;
+        this.io.pending = false;
+        this.io.dirty   = false;
+
+        this.idle = eventfd(0, 0);
+        if (idle < 0) {
+                abort("KERNEL ERROR: PROCESSOR EVENTFD - %s\n", strerror(errno));
+        }
 
         #if !defined(__CFA_NO_STATISTICS__)
@@ -521 +509 @@
         // Finally we don't need the read_lock any more
         unregister((__processor_id_t*)&this);
+
+        close(this.idle);
 }
 
 void ?{}(processor & this, const char name[], cluster & _cltr) {
-        ( this.idle ){};
         ( this.terminated ){};
         ( this.runner ){};
@@ -726 +715 @@
 }
 
-extern "C" {
-        char * strerror(int);
-}
-#define CHECKED(x) { int err = x; if( err != 0 ) abort("KERNEL ERROR: Operation \"" #x "\" return error %d - %s\n", err, strerror(err)); }
-
-static void ?{}(__bin_sem_t & this) with( this ) {
-        // Create the mutex with error checking
-        pthread_mutexattr_t mattr;
-        pthread_mutexattr_init( &mattr );
-        pthread_mutexattr_settype( &mattr, PTHREAD_MUTEX_ERRORCHECK_NP);
-        pthread_mutex_init(&lock, &mattr);
-
-        pthread_cond_init (&cond, (const pthread_condattr_t *)0p);  // workaround trac#208: cast should not be required
-        val = 0;
-}
-
-static void ^?{}(__bin_sem_t & this) with( this ) {
-        CHECKED( pthread_mutex_destroy(&lock) );
-        CHECKED( pthread_cond_destroy (&cond) );
-}
-
-#undef CHECKED
-
 #if defined(__CFA_WITH_VERIFY__)
 static bool verify_fwd_bck_rng(void) {

libcfa/src/concurrency/stats.cfa

@@ -33 +33 @@
                         stats->io.submit.slow       = 0;
                         stats->io.flush.external    = 0;
-                        stats->io.calls.count       = 0;
+                        stats->io.calls.flush       = 0;
                         stats->io.calls.submitted   = 0;
+                        stats->io.calls.drain       = 0;
                         stats->io.calls.completed   = 0;
-                        stats->io.calls.blocks      = 0;
                         stats->io.calls.errors.busy = 0;
                         stats->io.poller.sleeps     = 0;
@@ -67 +67 @@
                         __atomic_fetch_add( &cltr->io.submit.slow      , proc->io.submit.slow      , __ATOMIC_SEQ_CST ); proc->io.submit.slow       = 0;
                         __atomic_fetch_add( &cltr->io.flush.external   , proc->io.flush.external   , __ATOMIC_SEQ_CST ); proc->io.flush.external    = 0;
-                        __atomic_fetch_add( &cltr->io.calls.count      , proc->io.calls.count      , __ATOMIC_SEQ_CST ); proc->io.calls.count       = 0;
+                        __atomic_fetch_add( &cltr->io.calls.flush      , proc->io.calls.flush      , __ATOMIC_SEQ_CST ); proc->io.calls.flush       = 0;
                         __atomic_fetch_add( &cltr->io.calls.submitted  , proc->io.calls.submitted  , __ATOMIC_SEQ_CST ); proc->io.calls.submitted   = 0;
+                        __atomic_fetch_add( &cltr->io.calls.drain      , proc->io.calls.drain      , __ATOMIC_SEQ_CST ); proc->io.calls.drain       = 0;
                         __atomic_fetch_add( &cltr->io.calls.completed  , proc->io.calls.completed  , __ATOMIC_SEQ_CST ); proc->io.calls.completed   = 0;
-                        __atomic_fetch_add( &cltr->io.calls.blocks     , proc->io.calls.blocks     , __ATOMIC_SEQ_CST ); proc->io.calls.blocks      = 0;
                         __atomic_fetch_add( &cltr->io.calls.errors.busy, proc->io.calls.errors.busy, __ATOMIC_SEQ_CST ); proc->io.calls.errors.busy = 0;
                         __atomic_fetch_add( &cltr->io.poller.sleeps    , proc->io.poller.sleeps    , __ATOMIC_SEQ_CST ); proc->io.poller.sleeps     = 0;
@@ -110 +110 @@
                                 double avgfasts = ((double)io.submit.fast) / total_submits;
 
-                                double avgsubs = ((double)io.calls.submitted) / io.calls.count;
-                                double avgcomp = ((double)io.calls.completed) / io.calls.count;
+                                double avgsubs = ((double)io.calls.submitted) / io.calls.flush;
+                                double avgcomp = ((double)io.calls.completed) / io.calls.drain;
 
                                 __cfaabi_bits_print_safe( STDOUT_FILENO,
@@ -129 +129 @@
                                         , io.submit.fast, io.submit.slow, avgfasts
                                         , io.flush.external
-                                        , io.calls.count, io.calls.blocks, io.calls.errors.busy
+                                        , io.calls.flush, io.calls.drain, io.calls.errors.busy
                                         , io.calls.submitted, avgsubs
                                         , io.calls.completed, avgcomp

libcfa/src/concurrency/stats.hfa

@@ -80 +80 @@
                         } flush;
                         struct {
-                                volatile uint64_t count;
+                                volatile uint64_t drain;
+                                volatile uint64_t completed;
+                                volatile uint64_t flush;
                                 volatile uint64_t submitted;
-                                volatile uint64_t completed;
-                                volatile uint64_t blocks;
                                 struct {
                                         volatile uint64_t busy;