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Diffstat (limited to 'app/nginx/src/os/unix/ngx_file_aio_read.c')
-rw-r--r--app/nginx/src/os/unix/ngx_file_aio_read.c216
1 files changed, 216 insertions, 0 deletions
diff --git a/app/nginx/src/os/unix/ngx_file_aio_read.c b/app/nginx/src/os/unix/ngx_file_aio_read.c
new file mode 100644
index 0000000..aedc3c9
--- /dev/null
+++ b/app/nginx/src/os/unix/ngx_file_aio_read.c
@@ -0,0 +1,216 @@
+
+/*
+ * Copyright (C) Igor Sysoev
+ * Copyright (C) Nginx, Inc.
+ */
+
+
+#include <ngx_config.h>
+#include <ngx_core.h>
+#include <ngx_event.h>
+
+
+/*
+ * FreeBSD file AIO features and quirks:
+ *
+ * if an asked data are already in VM cache, then aio_error() returns 0,
+ * and the data are already copied in buffer;
+ *
+ * aio_read() preread in VM cache as minimum 16K (probably BKVASIZE);
+ * the first AIO preload may be up to 128K;
+ *
+ * aio_read/aio_error() may return EINPROGRESS for just written data;
+ *
+ * kqueue EVFILT_AIO filter is level triggered only: an event repeats
+ * until aio_return() will be called;
+ *
+ * aio_cancel() cannot cancel file AIO: it returns AIO_NOTCANCELED always.
+ */
+
+
+extern int ngx_kqueue;
+
+
+static ssize_t ngx_file_aio_result(ngx_file_t *file, ngx_event_aio_t *aio,
+ ngx_event_t *ev);
+static void ngx_file_aio_event_handler(ngx_event_t *ev);
+
+
+ngx_int_t
+ngx_file_aio_init(ngx_file_t *file, ngx_pool_t *pool)
+{
+ ngx_event_aio_t *aio;
+
+ 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;
+
+ return NGX_OK;
+}
+
+
+ssize_t
+ngx_file_aio_read(ngx_file_t *file, u_char *buf, size_t size, off_t offset,
+ ngx_pool_t *pool)
+{
+ int n;
+ ngx_event_t *ev;
+ ngx_event_aio_t *aio;
+
+ if (!ngx_file_aio) {
+ return ngx_read_file(file, buf, size, offset);
+ }
+
+ if (file->aio == NULL && ngx_file_aio_init(file, pool) != NGX_OK) {
+ return NGX_ERROR;
+ }
+
+ aio = file->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:%uz %V",
+ ev->complete, offset, size, &file->name);
+
+ if (ev->complete) {
+ ev->complete = 0;
+ ngx_set_errno(aio->err);
+
+ if (aio->err == 0) {
+ return aio->nbytes;
+ }
+
+ ngx_log_error(NGX_LOG_CRIT, file->log, ngx_errno,
+ "aio read \"%s\" failed", file->name.data);
+
+ return NGX_ERROR;
+ }
+
+ ngx_memzero(&aio->aiocb, sizeof(struct aiocb));
+
+ aio->aiocb.aio_fildes = file->fd;
+ aio->aiocb.aio_offset = offset;
+ aio->aiocb.aio_buf = buf;
+ aio->aiocb.aio_nbytes = size;
+#if (NGX_HAVE_KQUEUE)
+ aio->aiocb.aio_sigevent.sigev_notify_kqueue = ngx_kqueue;
+ aio->aiocb.aio_sigevent.sigev_notify = SIGEV_KEVENT;
+ aio->aiocb.aio_sigevent.sigev_value.sigval_ptr = ev;
+#endif
+ ev->handler = ngx_file_aio_event_handler;
+
+ n = aio_read(&aio->aiocb);
+
+ if (n == -1) {
+ n = ngx_errno;
+
+ if (n == NGX_EAGAIN) {
+ return ngx_read_file(file, buf, size, offset);
+ }
+
+ ngx_log_error(NGX_LOG_CRIT, file->log, n,
+ "aio_read(\"%V\") failed", &file->name);
+
+ if (n == NGX_ENOSYS) {
+ ngx_file_aio = 0;
+ return ngx_read_file(file, buf, size, offset);
+ }
+
+ return NGX_ERROR;
+ }
+
+ ngx_log_debug2(NGX_LOG_DEBUG_CORE, file->log, 0,
+ "aio_read: fd:%d %d", file->fd, n);
+
+ ev->active = 1;
+ ev->ready = 0;
+ ev->complete = 0;
+
+ return ngx_file_aio_result(aio->file, aio, ev);
+}
+
+
+static ssize_t
+ngx_file_aio_result(ngx_file_t *file, ngx_event_aio_t *aio, ngx_event_t *ev)
+{
+ int n;
+ ngx_err_t err;
+
+ n = aio_error(&aio->aiocb);
+
+ ngx_log_debug2(NGX_LOG_DEBUG_CORE, file->log, 0,
+ "aio_error: fd:%d %d", file->fd, n);
+
+ if (n == -1) {
+ err = ngx_errno;
+ aio->err = err;
+
+ ngx_log_error(NGX_LOG_ALERT, file->log, err,
+ "aio_error(\"%V\") failed", &file->name);
+ return NGX_ERROR;
+ }
+
+ if (n == NGX_EINPROGRESS) {
+ if (ev->ready) {
+ ev->ready = 0;
+ ngx_log_error(NGX_LOG_ALERT, file->log, n,
+ "aio_read(\"%V\") still in progress",
+ &file->name);
+ }
+
+ return NGX_AGAIN;
+ }
+
+ n = aio_return(&aio->aiocb);
+
+ if (n == -1) {
+ err = ngx_errno;
+ aio->err = err;
+ ev->ready = 1;
+
+ ngx_log_error(NGX_LOG_CRIT, file->log, err,
+ "aio_return(\"%V\") failed", &file->name);
+ return NGX_ERROR;
+ }
+
+ aio->err = 0;
+ aio->nbytes = n;
+ ev->ready = 1;
+ ev->active = 0;
+
+ ngx_log_debug2(NGX_LOG_DEBUG_CORE, file->log, 0,
+ "aio_return: fd:%d %d", file->fd, n);
+
+ return n;
+}
+
+
+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);
+
+ if (ngx_file_aio_result(aio->file, aio, ev) != NGX_AGAIN) {
+ aio->handler(ev);
+ }
+}