Implementing the ability to cancel request before worker starts processing it.

1 files changed, 51 insertions, 29 deletions

diff --git a/src/go/unit/nxt_go_run_ctx.c b/src/go/unit/nxt_go_run_ctx.c
index c5e41ee8..6aa5db77 100644
--- a/src/go/unit/nxt_go_run_ctx.c
+++ b/src/go/unit/nxt_go_run_ctx.c
@@ -85,6 +85,7 @@ static void
 nxt_go_ctx_init_msg(nxt_go_msg_t *msg, nxt_port_msg_t *port_msg,
     size_t payload_size)
 {
+    void                 *data, *end;
     nxt_port_mmap_msg_t  *mmap_msg;
 
     memset(msg, 0, sizeof(nxt_go_msg_t));
@@ -92,9 +93,17 @@ nxt_go_ctx_init_msg(nxt_go_msg_t *msg, nxt_port_msg_t *port_msg,
     msg->port_msg = port_msg;
     msg->raw_size = payload_size;
 
+    data = port_msg + 1;
+    end = nxt_pointer_to(data, payload_size);
+
+    if (port_msg->tracking) {
+        msg->tracking = data;
+        data = msg->tracking + 1;
+    }
+
     if (nxt_fast_path(port_msg->mmap != 0)) {
-        msg->mmap_msg = (nxt_port_mmap_msg_t *) (port_msg + 1);
-        msg->end = nxt_pointer_to(msg->mmap_msg, payload_size);
+        msg->mmap_msg = data;
+        msg->end = end;
 
         mmap_msg = msg->mmap_msg;
         while(mmap_msg < msg->end) {
@@ -134,7 +143,7 @@ nxt_go_ctx_release_msg(nxt_go_run_ctx_t *ctx, nxt_go_msg_t *msg)
         e = b + mmap_msg->size;
 
         while (b < e) {
-            nxt_port_mmap_set_chunk_free(port_mmap->hdr, c);
+            nxt_port_mmap_set_chunk_free(port_mmap->hdr->free_map, c);
 
             b += PORT_MMAP_CHUNK_SIZE;
             c++;
@@ -149,6 +158,10 @@ nxt_int_t
 nxt_go_ctx_init(nxt_go_run_ctx_t *ctx, nxt_port_msg_t *port_msg,
     size_t payload_size)
 {
+    nxt_atomic_t                  *val;
+    nxt_go_port_mmap_t            *port_mmap;
+    nxt_port_mmap_tracking_msg_t  *tracking;
+
     memset(ctx, 0, sizeof(nxt_go_run_ctx_t));
 
     ctx->process = nxt_go_get_process(port_msg->pid);
@@ -160,39 +173,45 @@ nxt_go_ctx_init(nxt_go_run_ctx_t *ctx, nxt_port_msg_t *port_msg,
 
     nxt_go_ctx_init_msg(&ctx->msg, port_msg, payload_size);
 
-    ctx->msg_last = &ctx->msg;
+    if (ctx->msg.tracking != NULL) {
+        tracking = ctx->msg.tracking;
 
-    ctx->wport_msg.stream = port_msg->stream;
-    ctx->wport_msg.pid = getpid();
-    ctx->wport_msg.type = _NXT_PORT_MSG_DATA;
-    ctx->wport_msg.mmap = 1;
+        if (nxt_slow_path(tracking->mmap_id >= ctx->process->incoming.nelts)) {
+            nxt_go_warn("incoming shared memory segment #%d not found "
+                        "for process %d", (int) tracking->mmap_id,
+                        (int) port_msg->pid);
 
-    ctx->wmmap_msg = (nxt_port_mmap_msg_t *) ( &ctx->wport_msg + 1 );
+            return NXT_ERROR;
+        }
 
-    return nxt_go_ctx_init_rbuf(ctx);
-}
+        nxt_go_mutex_lock(&ctx->process->incoming_mutex);
 
+        port_mmap = nxt_go_array_at(&ctx->process->incoming, tracking->mmap_id);
 
-void
-nxt_go_ctx_add_msg(nxt_go_run_ctx_t *ctx, nxt_port_msg_t *port_msg, size_t size)
-{
-    nxt_go_msg_t  *msg;
+        nxt_go_mutex_unlock(&ctx->process->incoming_mutex);
 
-    msg = malloc(sizeof(nxt_go_msg_t));
+        val = port_mmap->hdr->tracking + tracking->tracking_id;
 
-    nxt_go_ctx_init_msg(msg, port_msg, size - sizeof(nxt_port_msg_t));
+        ctx->cancelled = nxt_atomic_cmp_set(val, port_msg->stream, 0) == 0;
 
-    msg->start_offset = ctx->msg_last->start_offset;
+        if (ctx->cancelled) {
+            nxt_port_mmap_set_chunk_free(port_mmap->hdr->free_tracking_map,
+                                         tracking->tracking_id);
 
-    if (ctx->msg_last == &ctx->msg) {
-        msg->start_offset += ctx->request.body.preread_size;
-
-    } else {
-        msg->start_offset += ctx->msg_last->data_size;
+            return NXT_OK;
+        }
     }
 
-    ctx->msg_last->next = msg;
-    ctx->msg_last = msg;
+    ctx->msg_last = &ctx->msg;
+
+    ctx->wport_msg.stream = port_msg->stream;
+    ctx->wport_msg.pid = getpid();
+    ctx->wport_msg.type = _NXT_PORT_MSG_DATA;
+    ctx->wport_msg.mmap = 1;
+
+    ctx->wmmap_msg = (nxt_port_mmap_msg_t *) ( &ctx->wport_msg + 1 );
+
+    return nxt_go_ctx_init_rbuf(ctx);
 }
 
 
@@ -243,7 +262,8 @@ nxt_go_port_mmap_get_buf(nxt_go_run_ctx_t *ctx, size_t size)
 
     buf = &ctx->wbuf;
 
-    hdr = nxt_go_port_mmap_get(ctx->process, ctx->msg.port_msg->reply_port, &c);
+    hdr = nxt_go_port_mmap_get(ctx->process, ctx->msg.port_msg->reply_port, &c,
+                               0);
     if (nxt_slow_path(hdr == NULL)) {
         nxt_go_warn("failed to get port_mmap");
 
@@ -273,7 +293,7 @@ nxt_go_port_mmap_get_buf(nxt_go_run_ctx_t *ctx, size_t size)
     /* Try to acquire as much chunks as required. */
     while (nchunks > 0) {
 
-        if (nxt_port_mmap_chk_set_chunk_busy(hdr, c) == 0) {
+        if (nxt_port_mmap_chk_set_chunk_busy(hdr->free_map, c) == 0) {
             break;
         }
 
@@ -317,7 +337,7 @@ nxt_go_port_mmap_increase_buf(nxt_buf_t *b, size_t size, size_t min_size)
     /* Try to acquire as much chunks as required. */
     while (nchunks > 0) {
 
-        if (nxt_port_mmap_chk_set_chunk_busy(hdr, c) == 0) {
+        if (nxt_port_mmap_chk_set_chunk_busy(hdr->free_map, c) == 0) {
             break;
         }
 
@@ -330,7 +350,7 @@ nxt_go_port_mmap_increase_buf(nxt_buf_t *b, size_t size, size_t min_size)
     {
         c--;
         while (c >= start) {
-            nxt_port_mmap_set_chunk_free(hdr, c);
+            nxt_port_mmap_set_chunk_free(hdr->free_map, c);
             c--;
         }
 
@@ -438,6 +458,7 @@ nxt_go_ctx_read_size_(nxt_go_run_ctx_t *ctx, size_t *size)
     return NXT_OK;
 }
 
+
 nxt_int_t
 nxt_go_ctx_read_size(nxt_go_run_ctx_t *ctx, size_t *size)
 {
@@ -452,6 +473,7 @@ nxt_go_ctx_read_size(nxt_go_run_ctx_t *ctx, size_t *size)
     return rc;
 }
 
+
 nxt_int_t
 nxt_go_ctx_read_str(nxt_go_run_ctx_t *ctx, nxt_str_t *str)
 {