Juha-Matti Tilli(jmtilli) replied on github web page:
platform/linux-generic/pktio/null.c
line 93
@@ -0,0 +1,214 @@
+/* Copyright (c) 2017, Linaro Limited
+ * All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include "config.h"
+
+#include <odp_posix_extensions.h>
+
+#include <sys/socket.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <linux/if_packet.h>
+#include <linux/filter.h>
+#include <ctype.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <bits/wordsize.h>
+#include <net/ethernet.h>
+#include <netinet/ip.h>
+#include <arpa/inet.h>
+#include <stdint.h>
+#include <string.h>
+#include <net/if.h>
+#include <inttypes.h>
+#include <poll.h>
+#include <sys/ioctl.h>
+#include <errno.h>
+#include <sys/syscall.h>
+#include <linux/ethtool.h>
+#include <linux/sockios.h>
+
+#include <odp_api.h>
+#include <odp_packet_socket.h>
+#include <odp_packet_internal.h>
+#include <odp_packet_io_internal.h>
+#include <odp_align_internal.h>
+#include <odp_debug_internal.h>
+#include <odp_classification_datamodel.h>
+#include <odp_classification_inlines.h>
+#include <odp_classification_internal.h>
+#include <odp/api/hints.h>
+
+#include <protocols/eth.h>
+#include <protocols/ip.h>
+
+static int null_close(pktio_entry_t *pktio_entry ODP_UNUSED)
+{
+ return 0;
+}
+
+static int null_open(odp_pktio_t id ODP_UNUSED,
+ pktio_entry_t *pktio_entry ODP_UNUSED,
+ const char *devname, odp_pool_t pool ODP_UNUSED)
+{
+ if (strncmp(devname, "null:", 5) != 0)
+ return -1;
+ return 0;
+}
+
+static int null_recv(pktio_entry_t *pktio_entry ODP_UNUSED,
+ int index ODP_UNUSED, odp_packet_t pkt_table[] ODP_UNUSED,
+ int len ODP_UNUSED)
+{
+ return 0;
+}
+
+static int null_fd_set(pktio_entry_t *pktio_entry ODP_UNUSED,
+ int index ODP_UNUSED, fd_set *readfds)
+{
+ /* Somebody might wonder why readfds was not marked ODP_UNUSED.
+ * The reason is separately run checkpatch script complains that
+ * there must be spaces around '*', and if there are spaces, then
+ * the continuous integration build checkpatch script complains
+ * there must not be spaces around '*'. */
+ (void)readfds;
+ return 0;
+}
+
+static int null_recv_tmo(pktio_entry_t *pktio_entry ODP_UNUSED,
+ int index ODP_UNUSED,
+ odp_packet_t pkt_table[] ODP_UNUSED,
+ int num ODP_UNUSED, uint64_t usecs)
+{
+ struct timeval timeout;
+ int maxfd = -1;
+ fd_set readfds;
+
+ timeout.tv_sec = usecs / 1000 / 1000;
+ timeout.tv_usec = usecs % (1000 * 1000);
+ FD_ZERO(&readfds);
+
+ select(maxfd + 1, &readfds, NULL, NULL,
+ usecs == ODP_PKTIN_WAIT ? NULL : &timeout);
Comment:
I'm not entirely sure about this... If the programmer wants to wait
indefinitely, that's perhaps what we should do, which is indeed what is done
now. The odp_pktio_stop() comment should perhaps be made to the PR #341. A good
question is do we really need the empty readfds fd_set. Probably we could do
without it.
> Juha-Matti Tilli(jmtilli) wrote:
> Will do. This will result in a checkpatch warning then, but if that is not an
> obstacle to a merge, I can do this.
>> Juha-Matti Tilli(jmtilli) wrote:
>> Ok, the only reason I used this call was to increase code coverage. But is
>> it deprecated? I grepped through the repository, finding to evidence that
>> any API having the name mtu would be deprecated...
>>> Dmitry Eremin-Solenikov(lumag) wrote:
>>> This should be supportable also. Just like it is done in other software
>>> interfaces.
>>>> Dmitry Eremin-Solenikov(lumag) wrote:
>>>> Maybe we should add internal API to generate random (or semi-random) local
>>>> MAC-addresses with L bit being set?
>>>>> Dmitry Eremin-Solenikov(lumag) wrote:
>>>>> Just use ODP_UNUSED and forget about checkpatch being unoptimal here.
>>>>>> Dmitry Eremin-Solenikov(lumag) wrote:
>>>>>> just exit $STATUS. This would allow underlying program to return 42 to
>>>>>> mark the test as skipped
>>>>>>> Dmitry Eremin-Solenikov(lumag) wrote:
>>>>>>> this should go under `if test_example`
>>>>>>>> Dmitry Eremin-Solenikov(lumag) wrote:
>>>>>>>> I think this should be now in one of top-level .gitignore files.
>>>>>>>>> Dmitry Eremin-Solenikov(lumag) wrote:
>>>>>>>>> This should probably go to a separate PR. And ideally examples should
>>>>>>>>> not add much to code coverage on top of tests, so you might want also
>>>>>>>>> to add code to api testcases.
>>>>>>>>>> Bill Fischofer(Bill-Fischofer-Linaro) wrote:
>>>>>>>>>> `odp_pktio_mtu()` is a deprecated API and should not be used in new
>>>>>>>>>> code.
>>>>>>>>>>> Bill Fischofer(Bill-Fischofer-Linaro) wrote:
>>>>>>>>>>> Where does this "magic number" come from? Why not
>>>>>>>>>>> `00:00:00:00:00:00`?
>>>>>>>>>>>> Bill Fischofer(Bill-Fischofer-Linaro) wrote:
>>>>>>>>>>>> This is a deprecated API. Not sure we need to include it for a new
>>>>>>>>>>>> Pktio type.
>>>>>>>>>>>>> Bill Fischofer(Bill-Fischofer-Linaro) wrote:
>>>>>>>>>>>>> The parameter should be `num`, not `len` here.
>>>>>>>>>>>>>> Bill Fischofer(Bill-Fischofer-Linaro) wrote:
>>>>>>>>>>>>>> `odp_packet_free_multi()` would be better here.
>>>>>>>>>>>>>>> Bill Fischofer(Bill-Fischofer-Linaro) wrote:
>>>>>>>>>>>>>>> Same comments about `ODP_PKTIN_WAIT` here.
>>>>>>>>>>>>>>>> Bill Fischofer(Bill-Fischofer-Linaro) wrote:
>>>>>>>>>>>>>>>> Shouldn't it be an error to try to receive from a null device
>>>>>>>>>>>>>>>> with `ODP_PKTIN_WAIT` since such a call would never complete?
>>>>>>>>>>>>>>>> Alternately one could support such semantics and simply wait
>>>>>>>>>>>>>>>> indefinitely until `odp_pktio_stop()` is called to stop the
>>>>>>>>>>>>>>>> interface.
>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> Actually, looking at the semantics of `odp_pktio_stop()` we're
>>>>>>>>>>>>>>>> not precise about what happens if there are pending
>>>>>>>>>>>>>>>> `odp_pktio_recv_tmo()` call(s) on the interface at the time
>>>>>>>>>>>>>>>> `odp_pktio_stop()` is called. Presumably these should be
>>>>>>>>>>>>>>>> terminated, reporting no packets received when the stop call
>>>>>>>>>>>>>>>> is made.
>>>>>>>>>>>>>>>>> Bill Fischofer(Bill-Fischofer-Linaro) wrote:
>>>>>>>>>>>>>>>>> In this case it's probably better to be consistent and use
>>>>>>>>>>>>>>>>> `(void)pktio_entry` and `(void)index` as well. Mixing this
>>>>>>>>>>>>>>>>> idiom with `ODP_UNUSED` looks odd. It also needs no
>>>>>>>>>>>>>>>>> explanation as both are acceptable.
https://github.com/Linaro/odp/pull/365#discussion_r158597149
updated_at 2017-12-24 09:38:55
