Changeset 8e4aa05 for libcfa/src/concurrency/io/types.hfa

Timestamp:

Mar 4, 2021, 7:40:25 PM (5 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:

77d601f

Parents:

342af53 (diff), a5040fe (diff)
Note: this is a merge changeset, the changes displayed below correspond to the merge itself.
Use the (diff) links above to see all the changes relative to each parent.

Message:

Merge branch 'master' of plg.uwaterloo.ca:software/cfa/cfa-cc

File:

• libcfa/src/concurrency/io/types.hfa (modified) (7 diffs)

libcfa/src/concurrency/io/types.hfa

@@ -5 +5 @@
 // file "LICENCE" distributed with Cforall.
 //
-// io/types.hfa --
+// io/types.hfa -- PRIVATE
+// Types used by the I/O subsystem
 //
 // Author           : Thierry Delisle
@@ -21 +22 @@
 
 #include "bits/locks.hfa"
+#include "kernel/fwd.hfa"
 
 #if defined(CFA_HAVE_LINUX_IO_URING_H)
-        #define LEADER_LOCK
-        struct __leaderlock_t {
-                struct $thread * volatile value;        // ($thread) next_leader | (bool:1) is_locked
-        };
+        #include "bits/sequence.hfa"
+        #include "monitor.hfa"
 
-        static inline void ?{}( __leaderlock_t & this ) { this.value = 0p; }
+        struct processor;
+        monitor $io_arbiter;
 
         //-----------------------------------------------------------------------
         // Ring Data structure
-      struct __submition_data {
-                // Head and tail of the ring (associated with array)
-                volatile __u32 * head;
-                volatile __u32 * tail;
-                volatile __u32 prev_head;
+      struct __sub_ring_t {
+                struct {
+                        // Head and tail of the ring (associated with array)
+                        volatile __u32 * head;   // one passed last index consumed by the kernel
+                        volatile __u32 * tail;   // one passed last index visible to the kernel
+                        volatile __u32 released; // one passed last index released back to the free list
 
-                // The actual kernel ring which uses head/tail
-                // indexes into the sqes arrays
-                __u32 * array;
+                        // The actual kernel ring which uses head/tail
+                        // indexes into the sqes arrays
+                        __u32 * array;
+                } kring;
+
+                struct {
+                        volatile __u32 head;
+                        volatile __u32 tail;
+                        // The ring which contains free allocations
+                        // indexes into the sqes arrays
+                        __u32 * array;
+                } free_ring;
+
+                // number of sqes to submit on next system call.
+                __u32 to_submit;
 
                 // number of entries and mask to go with it
@@ -46 +60 @@
                 const __u32 * mask;
 
-                // Submission flags (Not sure what for)
+                // Submission flags, currently only IORING_SETUP_SQPOLL
                 __u32 * flags;
 
-                // number of sqes not submitted (whatever that means)
+                // number of sqes not submitted
+                // From documentation : [dropped] is incremented for each invalid submission queue entry encountered in the ring buffer.
                 __u32 * dropped;
 
-                // Like head/tail but not seen by the kernel
-                volatile __u32 * ready;
-                __u32 ready_cnt;
-                __u32 prev_ready;
-
-                #if defined(LEADER_LOCK)
-                        __leaderlock_t submit_lock;
-                #else
-                        __spinlock_t submit_lock;
-                #endif
-                __spinlock_t  release_lock;
-
                 // A buffer of sqes (not the actual ring)
-                volatile struct io_uring_sqe * sqes;
+                struct io_uring_sqe * sqes;
 
                 // The location and size of the mmaped area
@@ -72 +75 @@
         };
 
-        struct __completion_data {
+        struct __cmp_ring_t {
                 // Head and tail of the ring
                 volatile __u32 * head;
@@ -81 +84 @@
                 const __u32 * num;
 
-                // number of cqes not submitted (whatever that means)
+                // I don't know what this value is for
                 __u32 * overflow;
 
@@ -92 +95 @@
         };
 
-        struct __io_data {
-                struct __submition_data submit_q;
-                struct __completion_data completion_q;
+        struct __attribute__((aligned(128))) $io_context {
+                $io_arbiter * arbiter;
+                processor * proc;
+
+                struct {
+                        volatile bool empty;
+                        condition blocked;
+                } ext_sq;
+
+                struct __sub_ring_t sq;
+                struct __cmp_ring_t cq;
                 __u32 ring_flags;
                 int fd;
-                int efd;
-                bool eager_submits:1;
-                bool poller_submits:1;
+        };
+
+        monitor __attribute__((aligned(128))) $io_arbiter {
+                struct {
+                        condition blocked;
+                        $io_context * ctx;
+                        volatile bool flag;
+                } pending;
         };
 
@@ -131 +147 @@
         #endif
 
-        struct $io_ctx_thread;
-        void __ioctx_register($io_ctx_thread & ctx);
-        void __ioctx_prepare_block($io_ctx_thread & ctx);
-        void __sqe_clean( volatile struct io_uring_sqe * sqe );
+        // void __ioctx_prepare_block($io_context & ctx);
 #endif