When a task manager is created, we can now specify an `isc_nm`
object to associate with it; thereafter when the task manager is
placed into exclusive mode, the network manager will be paused.
This is a replacement for the existing isc_socket and isc_socketmgr
implementation. It uses libuv for asynchronous network communication;
"networker" objects will be distributed across worker threads reading
incoming packets and sending them for processing.
UDP listener sockets automatically create an array of "child" sockets
so each worker can listen separately.
TCP sockets are shared amongst worker threads.
A TCPDNS socket is a wrapper around a TCP socket, which handles the
the two-byte length field at the beginning of DNS messages over TCP.
(Other wrapper socket types can be implemented in the future to handle
DNS over TLS, DNS over HTTPS, etc.)
isc_event_allocate() calls isc_mem_get() to allocate the event structure. As
isc_mem_get() cannot fail softly (e.g. it never returns NULL), the
isc_event_allocate() cannot return NULL, hence we remove the (ret == NULL)
handling blocks using the semantic patch from the previous commit.
Previously isc_thread_join() would return ISC_R_UNEXPECTED on a failure to
create new thread. All such occurences were caught and wrapped into assert
function at higher level. The function was simplified to assert directly in the
isc_thread_join() function and all caller level assertions were removed.
Previously isc_thread_create() would return ISC_R_UNEXPECTED on a failure to
create new thread. All such occurences were caught and wrapped into assert
function at higher level. The function was simplified to assert directly in the
isc_thread_create() function and all caller level assertions were removed.
The json-c have previously leaked into the global namespace leading
to forced -I<include_path> for every compilation unit using isc/xml.h
header. This MR fixes the usage making the caller object opaque.
The libxml2 have previously leaked into the global namespace leading
to forced -I<include_path> for every compilation unit using isc/xml.h
header. This MR fixes the usage making the caller object opaque.
Compiling with -O3 triggers the following warnings with GCC 9.1:
task.c: In function ‘isc_taskmgr_create’:
task.c:1384:43: warning: ‘%04u’ directive output may be truncated writing between 4 and 10 bytes into a region of size 6 [-Wformat-truncation=]
1384 | snprintf(name, sizeof(name), "isc-worker%04u", i);
| ^~~~
task.c:1384:32: note: directive argument in the range [0, 4294967294]
1384 | snprintf(name, sizeof(name), "isc-worker%04u", i);
| ^~~~~~~~~~~~~~~~
task.c:1384:3: note: ‘snprintf’ output between 15 and 21 bytes into a destination of size 16
1384 | snprintf(name, sizeof(name), "isc-worker%04u", i);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
private_test.c: In function ‘private_nsec3_totext_test’:
private_test.c:110:9: warning: array subscript 4 is outside array bounds of ‘uint32_t[1]’ {aka ‘unsigned int[1]’} [-Warray-bounds]
110 | while (*sp == '\0' && slen > 0) {
| ^~~
private_test.c:103:11: note: while referencing ‘salt’
103 | uint32_t salt;
| ^~~~
Prevent these warnings from being triggered by increasing the size of
the relevant array (task.c) and reordering conditions (private_test.c).
This work cleans up the API which includes couple of things:
1. Make the isc_appctx_t type fully opaque
2. Protect all access to the isc_app_t members via stdatomics
3. sigwait() is part of POSIX.1, remove dead non-sigwait code
4. Remove unused code: isc_appctx_set{taskmgr,sockmgr,timermgr}
If we know that we'll have a task pool doing specific thing it's better
to use this knowledge and bind tasks to task queues, this behaves better
than randomly choosing the task queue.
- use bound resolver tasks - we have a pool of tasks doing resolutions,
we can spread the load evenly using isc_task_create_bound
- quantum set universally to 25
