mir/bind
2
0
Fork 0
mirror of https://gitlab.isc.org/isc-projects/bind9 synced 2025-08-31 06:25:31 +00:00
Code Issues Releases Wiki Activity

change from isc_nmhandle_ref/unref to isc_nmhandle attach/detach

Browse Source 
Attaching and detaching handle pointers will make it easier to
determine where and why reference counting errors have occurred.

A handle needs to be referenced more than once when multiple
asynchronous operations are in flight, so callers must now maintain
multiple handle pointers for each pending operation. For example,
ns_client objects now contain:

        - reqhandle:    held while waiting for a request callback (query,
                        notify, update)
        - sendhandle:   held while waiting for a send callback
        - fetchhandle:  held while waiting for a recursive fetch to
                        complete
        - updatehandle: held while waiting for an update-forwarding
                        task to complete

control channel connection objects now contain:

        - readhandle: held while waiting for a read callback
        - sendhandle: held while waiting for a send callback
        - cmdhandle:  held while an rndc command is running

httpd connections contain:

        - readhandle: held while waiting for a read callback
        - sendhandle: held while waiting for a send callback
This commit is contained in:
Evan Hunt
2020-09-03 13:31:27 -07:00
parent cfa4ea64bc
commit 57b4dde974
26 changed files with 416 additions and 309 deletions
Download Patch File Download Diff File Expand all files Collapse all files

36
lib/isc/netmgr/udp.c
View File

@@ -159,7 +159,7 @@ udp_alloc_cb(uv_handle_t *handle, size_t size, uv_buf_t *buf) {
}
/*
* handle 'udplisten' async call - start listening on a socket.
* Asynchronous 'udplisten' call handler: start listening on a UDP socket.
*/
void
isc__nm_async_udplisten(isc__networker_t *worker, isc__netievent_t *ev0) {
@@ -311,7 +311,7 @@ isc__nm_udp_stoplistening(isc_nmsocket_t *sock) {
}
/*
* handle 'udpstop' async call - stop listening on a socket.
* Asynchronous 'udpstop' call handler: stop listening on a UDP socket.
*/
void
isc__nm_async_udpstop(isc__networker_t *worker, isc__netievent_t *ev0) {
@@ -375,9 +375,9 @@ udp_recv_cb(uv_udp_t *handle, ssize_t nrecv, const uv_buf_t *buf,
#endif
/*
* Three reasons to return now without processing:
* - If addr == NULL that's the end of stream - we can
* free the buffer and bail.
* Three possible reasons to return now without processing:
* - If addr == NULL, in which case it's the end of stream;
* we can free the buffer and bail.
* - If we're simulating a firewall blocking UDP packets
* bigger than 'maxudp' bytes for testing purposes.
* - If the socket is no longer active.
@@ -395,11 +395,7 @@ udp_recv_cb(uv_udp_t *handle, ssize_t nrecv, const uv_buf_t *buf,
result = isc_sockaddr_fromsockaddr(&sockaddr, addr);
RUNTIME_CHECK(result == ISC_R_SUCCESS);
if (!atomic_load(&sock->connected)) {
nmhandle = isc__nmhandle_get(sock, &sockaddr, NULL);
} else {
nmhandle = sock->statichandle;
}
nmhandle = isc__nmhandle_get(sock, &sockaddr, NULL);
region.base = (unsigned char *)buf->base;
region.length = nrecv;
@@ -418,13 +414,13 @@ udp_recv_cb(uv_udp_t *handle, ssize_t nrecv, const uv_buf_t *buf,
* If the recv callback wants to hold on to the handle,
* it needs to attach to it.
*/
isc_nmhandle_unref(nmhandle);
isc_nmhandle_detach(&nmhandle);
}
/*
* isc__nm_udp_send sends buf to a peer on a socket.
* It tries to find a proper sibling/child socket so that we won't have
* to jump to another thread.
* Send the data in 'region' to a peer via a UDP socket. We try to find
* a proper sibling/child socket so that we won't have to jump to another
* thread.
*/
isc_result_t
isc__nm_udp_send(isc_nmhandle_t *handle, isc_region_t *region, isc_nm_cb_t cb,
@@ -446,7 +442,7 @@ isc__nm_udp_send(isc_nmhandle_t *handle, isc_region_t *region, isc_nm_cb_t cb,
* we need to do so here.
*/
if (maxudp != 0 && region->length > maxudp) {
isc_nmhandle_unref(handle);
isc_nmhandle_detach(&handle);
return (ISC_R_SUCCESS);
}
@@ -486,8 +482,7 @@ isc__nm_udp_send(isc_nmhandle_t *handle, isc_region_t *region, isc_nm_cb_t cb,
uvreq->uvbuf.base = (char *)region->base;
uvreq->uvbuf.len = region->length;
uvreq->handle = handle;
isc_nmhandle_ref(uvreq->handle);
isc_nmhandle_attach(handle, &uvreq->handle);
uvreq->cb.send = cb;
uvreq->cbarg = cbarg;
@@ -514,7 +509,7 @@ isc__nm_udp_send(isc_nmhandle_t *handle, isc_region_t *region, isc_nm_cb_t cb,
}
/*
* handle 'udpsend' async event - send a packet on the socket
* Asynchronous 'udpsend' event handler: send a packet on a UDP socket.
*/
void
isc__nm_async_udpsend(isc__networker_t *worker, isc__netievent_t *ev0) {
@@ -531,9 +526,6 @@ isc__nm_async_udpsend(isc__networker_t *worker, isc__netievent_t *ev0) {
}
}
/*
* udp_send_cb - callback
*/
static void
udp_send_cb(uv_udp_send_t *req, int status) {
isc_result_t result = ISC_R_SUCCESS;
@@ -549,7 +541,6 @@ udp_send_cb(uv_udp_send_t *req, int status) {
}
uvreq->cb.send(uvreq->handle, result, uvreq->cbarg);
isc_nmhandle_unref(uvreq->handle);
isc__nm_uvreq_put(&uvreq, uvreq->sock);
}
@@ -570,7 +561,6 @@ udp_send_direct(isc_nmsocket_t *sock, isc__nm_uvreq_t *req,
return (ISC_R_CANCELED);
}
isc_nmhandle_ref(req->handle);
sa = atomic_load(&sock->connected) ? NULL : &peer->type.sa;
rv = uv_udp_send(&req->uv_req.udp_send, &sock->uv_handle.udp,
&req->uvbuf, 1, sa, udp_send_cb);