[MAJOR] buffer: flag BF_DONT_READ to disable reads when not required
When processing a GET or HEAD request in close mode, we know we don't
need to read anything anymore on the socket, so we can disable it.
Doing this can save up to 40% of the recv calls, and half of the
epoll_ctl calls.
For this we need a buffer flag indicating that we're not interesting in
reading anymore. Right now, this flag also disables both polled reads.
We might benefit from disabling only speculative reads, but we will need
at least this flag when we want to support keepalive anyway.
Currently we don't disable the flag on completion, but it does not
matter as we close ASAP when performing the shutw().
diff --git a/include/types/buffers.h b/include/types/buffers.h
index fc070bd..8c8ee9b 100644
--- a/include/types/buffers.h
+++ b/include/types/buffers.h
@@ -111,6 +111,8 @@
#define BF_READ_DONTWAIT 0x400000 /* wake the task up after every read (eg: HTTP request) */
#define BF_AUTO_CONNECT 0x800000 /* consumer may attempt to establish a new connection */
+#define BF_DONT_READ 0x1000000 /* disable reading for now */
+
/* Use these masks to clear the flags before going back to lower layers */
#define BF_CLEAR_READ (~(BF_READ_NULL|BF_READ_PARTIAL|BF_READ_ERROR|BF_READ_ATTACHED))
#define BF_CLEAR_WRITE (~(BF_WRITE_NULL|BF_WRITE_PARTIAL|BF_WRITE_ERROR))