diff src/os/unix/ngx_linux_aio_read.c @ 518:86dad910eeb6 NGINX_0_8_11

nginx 0.8.11 *) Change: directive "gzip_disable msie6" enables gzipping for MSIE 6.0 SV1. *) Feature: file AIO support on FreeBSD and Linux. *) Feature: the "directio_alignment" directive.
author Igor Sysoev <http://sysoev.ru>
date Fri, 28 Aug 2009 00:00:00 +0400
parents
children 2b9e388c61f1
line wrap: on
line diff
new file mode 100644
--- /dev/null
+++ b/src/os/unix/ngx_linux_aio_read.c
@@ -0,0 +1,131 @@
+
+/*
+ * Copyright (C) Igor Sysoev
+ */
+
+
+#include <ngx_config.h>
+#include <ngx_core.h>
+#include <ngx_event.h>
+
+
+extern int            ngx_eventfd;
+extern aio_context_t  ngx_aio_ctx;
+
+
+static void ngx_file_aio_event_handler(ngx_event_t *ev);
+
+
+static long
+io_submit(aio_context_t ctx, long n, struct iocb **paiocb)
+{
+    return syscall(SYS_io_submit, ctx, n, paiocb);
+}
+
+
+ssize_t
+ngx_file_aio_read(ngx_file_t *file, u_char *buf, size_t size, off_t offset,
+    ngx_pool_t *pool)
+{
+    long                n;
+    struct iocb        *piocb[1];
+    ngx_event_t        *ev;
+    ngx_event_aio_t    *aio;
+    static ngx_uint_t   enosys = 0;
+
+    if (enosys) {
+        return ngx_read_file(file, buf, size, offset);
+    }
+
+    aio = file->aio;
+
+    if (aio == NULL) {
+        aio = ngx_pcalloc(pool, sizeof(ngx_event_aio_t));
+        if (aio == NULL) {
+            return NGX_ERROR;
+        }
+
+        aio->file = file;
+        aio->fd = file->fd;
+        aio->event.data = aio;
+        aio->event.ready = 1;
+        aio->event.log = file->log;
+        file->aio = aio;
+    }
+
+    ev = &aio->event;
+
+    if (!ev->ready) {
+        ngx_log_error(NGX_LOG_ALERT, file->log, 0,
+                      "second aio post for \"%V\"", &file->name);
+        return NGX_AGAIN;
+    }
+
+    ngx_log_debug4(NGX_LOG_DEBUG_CORE, file->log, 0,
+                   "aio complete:%d @%O:%z %V",
+                   ev->complete, offset, size, &file->name);
+
+    if (ev->complete) {
+        ev->active = 0;
+        ev->complete = 0;
+
+        if (aio->res >= 0) {
+            ngx_set_errno(0);
+            return aio->res;
+        }
+
+        ngx_set_errno(-aio->res);
+        return NGX_ERROR;
+    }
+
+    ngx_memzero(&aio->aiocb, sizeof(struct iocb));
+
+    aio->aiocb.aio_data = (uint64_t) (uintptr_t) ev;
+    aio->aiocb.aio_lio_opcode = IOCB_CMD_PREAD;
+    aio->aiocb.aio_fildes = file->fd;
+    aio->aiocb.aio_buf = (uint64_t) (uintptr_t) buf;
+    aio->aiocb.aio_nbytes = size;
+    aio->aiocb.aio_offset = offset;
+    aio->aiocb.aio_flags = IOCB_FLAG_RESFD;
+    aio->aiocb.aio_resfd = ngx_eventfd;
+
+    ev->handler = ngx_file_aio_event_handler;
+
+    piocb[0] = &aio->aiocb;
+
+    n = io_submit(ngx_aio_ctx, 1, piocb);
+
+    if (n == 1) {
+        return NGX_AGAIN;
+    }
+
+    n = -n;
+
+    if (n == NGX_EAGAIN) {
+        return ngx_read_file(file, buf, size, offset);
+    }
+
+    ngx_log_error(NGX_LOG_CRIT, file->log, n,
+                  "io_submit(\"%V\") failed", &file->name);
+
+    if (n == NGX_ENOSYS) {
+        enosys = 1;
+        return ngx_read_file(file, buf, size, offset);
+    }
+
+    return NGX_ERROR;
+}
+
+
+static void
+ngx_file_aio_event_handler(ngx_event_t *ev)
+{
+    ngx_event_aio_t  *aio;
+
+    aio = ev->data;
+
+    ngx_log_debug2(NGX_LOG_DEBUG_CORE, ev->log, 0,
+                   "aio event handler fd:%d %V", aio->fd, &aio->file->name);
+
+    aio->handler(ev);
+}