This is a follow-up to the commit 9b2b86332a9b ("bpf: Allow to use kfunc
XDP hints and frags together").
The are some possible implementations problems that may arise when
providing metadata specifically for multi-buffer packets, therefore there
must be a possibility to test such option separately.
Add an option to use multi-buffer AF_XDP xdp_hw_metadata and mark used XDP
program as capable to use frags.
As for now, xdp_hw_metadata accepts no options, so add simple option
parsing logic and a help message.
For quick reference, also add an ingress packet generation command to the
help message. The command comes from [0].
Example of output for multi-buffer packet:
xsk_ring_cons__peek: 1
0xead018: rx_desc[15]->addr=10000000000f000 addr=f100 comp_addr=f000
rx_hash: 0x5789FCBB with RSS type:0x29
rx_timestamp: 1696856851535324697 (sec:1696856851.5353)
XDP RX-time: 1696856843158256391 (sec:1696856843.1583)
delta sec:-8.3771 (-8377068.306 usec)
AF_XDP time: 1696856843158413078 (sec:1696856843.1584)
delta sec:0.0002 (156.687 usec)
0xead018: complete idx=23 addr=f000
xsk_ring_cons__peek: 1
0xead018: rx_desc[16]->addr=100000000008000 addr=8100 comp_addr=8000
0xead018: complete idx=24 addr=8000
xsk_ring_cons__peek: 1
0xead018: rx_desc[17]->addr=100000000009000 addr=9100 comp_addr=9000 EoP
0xead018: complete idx=25 addr=9000
Metadata is printed for the first packet only.
[0] https://lore.kernel.org/all/[email protected]/
Signed-off-by: Larysa Zaremba <[email protected]>
---
.../selftests/bpf/progs/xdp_hw_metadata.c | 2 +-
tools/testing/selftests/bpf/xdp_hw_metadata.c | 92 ++++++++++++++++---
2 files changed, 79 insertions(+), 15 deletions(-)
diff --git a/tools/testing/selftests/bpf/progs/xdp_hw_metadata.c b/tools/testing/selftests/bpf/progs/xdp_hw_metadata.c
index 63d7de6c6bbb..8767d919c881 100644
--- a/tools/testing/selftests/bpf/progs/xdp_hw_metadata.c
+++ b/tools/testing/selftests/bpf/progs/xdp_hw_metadata.c
@@ -21,7 +21,7 @@ extern int bpf_xdp_metadata_rx_timestamp(const struct xdp_md *ctx,
extern int bpf_xdp_metadata_rx_hash(const struct xdp_md *ctx, __u32 *hash,
enum xdp_rss_hash_type *rss_type) __ksym;
-SEC("xdp")
+SEC("xdp.frags")
int rx(struct xdp_md *ctx)
{
void *data, *data_meta, *data_end;
diff --git a/tools/testing/selftests/bpf/xdp_hw_metadata.c b/tools/testing/selftests/bpf/xdp_hw_metadata.c
index 17c980138796..25225720346b 100644
--- a/tools/testing/selftests/bpf/xdp_hw_metadata.c
+++ b/tools/testing/selftests/bpf/xdp_hw_metadata.c
@@ -26,6 +26,7 @@
#include <linux/sockios.h>
#include <sys/mman.h>
#include <net/if.h>
+#include <ctype.h>
#include <poll.h>
#include <time.h>
@@ -49,19 +50,29 @@ struct xsk {
struct xdp_hw_metadata *bpf_obj;
struct xsk *rx_xsk;
const char *ifname;
+bool use_frags;
int ifindex;
int rxq;
void test__fail(void) { /* for network_helpers.c */ }
-static int open_xsk(int ifindex, struct xsk *xsk, __u32 queue_id)
+static struct xsk_socket_config gen_socket_config(void)
{
- int mmap_flags = MAP_PRIVATE | MAP_ANONYMOUS | MAP_NORESERVE;
- const struct xsk_socket_config socket_config = {
+ struct xsk_socket_config socket_config = {
.rx_size = XSK_RING_PROD__DEFAULT_NUM_DESCS,
.tx_size = XSK_RING_PROD__DEFAULT_NUM_DESCS,
.bind_flags = XDP_COPY,
};
+
+ if (use_frags)
+ socket_config.bind_flags |= XDP_USE_SG;
+ return socket_config;
+}
+
+static int open_xsk(int ifindex, struct xsk *xsk, __u32 queue_id)
+{
+ int mmap_flags = MAP_PRIVATE | MAP_ANONYMOUS | MAP_NORESERVE;
+ struct xsk_socket_config socket_config = gen_socket_config();
const struct xsk_umem_config umem_config = {
.fill_size = XSK_RING_PROD__DEFAULT_NUM_DESCS,
.comp_size = XSK_RING_CONS__DEFAULT_NUM_DESCS,
@@ -263,11 +274,14 @@ static int verify_metadata(struct xsk *rx_xsk, int rxq, int server_fd, clockid_t
verify_skb_metadata(server_fd);
for (i = 0; i < rxq; i++) {
+ bool first_seg = true;
+ bool is_eop = true;
+
if (fds[i].revents == 0)
continue;
struct xsk *xsk = &rx_xsk[i];
-
+peek:
ret = xsk_ring_cons__peek(&xsk->rx, 1, &idx);
printf("xsk_ring_cons__peek: %d\n", ret);
if (ret != 1)
@@ -276,12 +290,19 @@ static int verify_metadata(struct xsk *rx_xsk, int rxq, int server_fd, clockid_t
rx_desc = xsk_ring_cons__rx_desc(&xsk->rx, idx);
comp_addr = xsk_umem__extract_addr(rx_desc->addr);
addr = xsk_umem__add_offset_to_addr(rx_desc->addr);
- printf("%p: rx_desc[%u]->addr=%llx addr=%llx comp_addr=%llx\n",
- xsk, idx, rx_desc->addr, addr, comp_addr);
- verify_xdp_metadata(xsk_umem__get_data(xsk->umem_area, addr),
- clock_id);
+ is_eop = !(rx_desc->options & XDP_PKT_CONTD);
+ printf("%p: rx_desc[%u]->addr=%llx addr=%llx comp_addr=%llx%s\n",
+ xsk, idx, rx_desc->addr, addr, comp_addr, is_eop ? " EoP" : "");
+ if (first_seg) {
+ verify_xdp_metadata(xsk_umem__get_data(xsk->umem_area, addr),
+ clock_id);
+ first_seg = false;
+ }
+
xsk_ring_cons__release(&xsk->rx, 1);
refill_rx(xsk, comp_addr);
+ if (!is_eop)
+ goto peek;
}
}
@@ -404,6 +425,54 @@ static void timestamping_enable(int fd, int val)
error(1, errno, "setsockopt(SO_TIMESTAMPING)");
}
+static void print_usage(void)
+{
+ const char *usage =
+ " Usage: xdp_hw_metadata [OPTIONS] [IFNAME]\n"
+ " Options:\n"
+ " -m Enable multi-buffer XDP for larger MTU\n"
+ " -h Display this help and exit\n\n"
+ " Generate test packets on the other machine with:\n"
+ " echo -n xdp | nc -u -q1 <dst_ip> 9091\n";
+
+ printf("%s", usage);
+}
+
+static void read_args(int argc, char *argv[])
+{
+ char opt;
+
+ while ((opt = getopt(argc, argv, "mh")) != -1) {
+ switch (opt) {
+ case 'm':
+ use_frags = true;
+ break;
+ case 'h':
+ print_usage();
+ exit(0);
+ case '?':
+ if (isprint(optopt))
+ fprintf(stderr, "Unknown option: -%c\n", optopt);
+ fallthrough;
+ default:
+ print_usage();
+ error(-1, opterr, "Command line options error");
+ }
+ }
+
+ if (optind >= argc) {
+ fprintf(stderr, "No device name provided\n");
+ print_usage();
+ exit(-1);
+ }
+
+ ifname = argv[optind];
+ ifindex = if_nametoindex(ifname);
+
+ if (!ifname)
+ error(-1, errno, "Invalid interface name");
+}
+
int main(int argc, char *argv[])
{
clockid_t clock_id = CLOCK_TAI;
@@ -413,13 +482,8 @@ int main(int argc, char *argv[])
struct bpf_program *prog;
- if (argc != 2) {
- fprintf(stderr, "pass device name\n");
- return -1;
- }
+ read_args(argc, argv);
- ifname = argv[1];
- ifindex = if_nametoindex(ifname);
rxq = rxq_num(ifname);
printf("rxq: %d\n", rxq);
--
2.41.0
On 10/09, Larysa Zaremba wrote:
> This is a follow-up to the commit 9b2b86332a9b ("bpf: Allow to use kfunc
> XDP hints and frags together").
>
> The are some possible implementations problems that may arise when
> providing metadata specifically for multi-buffer packets, therefore there
> must be a possibility to test such option separately.
>
> Add an option to use multi-buffer AF_XDP xdp_hw_metadata and mark used XDP
> program as capable to use frags.
>
> As for now, xdp_hw_metadata accepts no options, so add simple option
> parsing logic and a help message.
>
> For quick reference, also add an ingress packet generation command to the
> help message. The command comes from [0].
>
> Example of output for multi-buffer packet:
>
> xsk_ring_cons__peek: 1
> 0xead018: rx_desc[15]->addr=10000000000f000 addr=f100 comp_addr=f000
> rx_hash: 0x5789FCBB with RSS type:0x29
> rx_timestamp: 1696856851535324697 (sec:1696856851.5353)
> XDP RX-time: 1696856843158256391 (sec:1696856843.1583)
> delta sec:-8.3771 (-8377068.306 usec)
> AF_XDP time: 1696856843158413078 (sec:1696856843.1584)
> delta sec:0.0002 (156.687 usec)
> 0xead018: complete idx=23 addr=f000
> xsk_ring_cons__peek: 1
> 0xead018: rx_desc[16]->addr=100000000008000 addr=8100 comp_addr=8000
> 0xead018: complete idx=24 addr=8000
> xsk_ring_cons__peek: 1
> 0xead018: rx_desc[17]->addr=100000000009000 addr=9100 comp_addr=9000 EoP
> 0xead018: complete idx=25 addr=9000
>
> Metadata is printed for the first packet only.
>
> [0] https://lore.kernel.org/all/[email protected]/
>
> Signed-off-by: Larysa Zaremba <[email protected]>
> ---
> .../selftests/bpf/progs/xdp_hw_metadata.c | 2 +-
> tools/testing/selftests/bpf/xdp_hw_metadata.c | 92 ++++++++++++++++---
> 2 files changed, 79 insertions(+), 15 deletions(-)
>
> diff --git a/tools/testing/selftests/bpf/progs/xdp_hw_metadata.c b/tools/testing/selftests/bpf/progs/xdp_hw_metadata.c
> index 63d7de6c6bbb..8767d919c881 100644
> --- a/tools/testing/selftests/bpf/progs/xdp_hw_metadata.c
> +++ b/tools/testing/selftests/bpf/progs/xdp_hw_metadata.c
> @@ -21,7 +21,7 @@ extern int bpf_xdp_metadata_rx_timestamp(const struct xdp_md *ctx,
> extern int bpf_xdp_metadata_rx_hash(const struct xdp_md *ctx, __u32 *hash,
> enum xdp_rss_hash_type *rss_type) __ksym;
>
> -SEC("xdp")
> +SEC("xdp.frags")
> int rx(struct xdp_md *ctx)
> {
> void *data, *data_meta, *data_end;
> diff --git a/tools/testing/selftests/bpf/xdp_hw_metadata.c b/tools/testing/selftests/bpf/xdp_hw_metadata.c
> index 17c980138796..25225720346b 100644
> --- a/tools/testing/selftests/bpf/xdp_hw_metadata.c
> +++ b/tools/testing/selftests/bpf/xdp_hw_metadata.c
> @@ -26,6 +26,7 @@
> #include <linux/sockios.h>
> #include <sys/mman.h>
> #include <net/if.h>
> +#include <ctype.h>
> #include <poll.h>
> #include <time.h>
>
> @@ -49,19 +50,29 @@ struct xsk {
> struct xdp_hw_metadata *bpf_obj;
> struct xsk *rx_xsk;
> const char *ifname;
> +bool use_frags;
> int ifindex;
> int rxq;
>
> void test__fail(void) { /* for network_helpers.c */ }
>
> -static int open_xsk(int ifindex, struct xsk *xsk, __u32 queue_id)
> +static struct xsk_socket_config gen_socket_config(void)
> {
> - int mmap_flags = MAP_PRIVATE | MAP_ANONYMOUS | MAP_NORESERVE;
> - const struct xsk_socket_config socket_config = {
> + struct xsk_socket_config socket_config = {
> .rx_size = XSK_RING_PROD__DEFAULT_NUM_DESCS,
> .tx_size = XSK_RING_PROD__DEFAULT_NUM_DESCS,
> .bind_flags = XDP_COPY,
> };
> +
> + if (use_frags)
> + socket_config.bind_flags |= XDP_USE_SG;
> + return socket_config;
> +}
nit: why not drop const from socket_config and add this 'if (use_frags)'
directly to open_xsk? Not sure separate function really buys us anything?
> +static int open_xsk(int ifindex, struct xsk *xsk, __u32 queue_id)
> +{
> + int mmap_flags = MAP_PRIVATE | MAP_ANONYMOUS | MAP_NORESERVE;
> + struct xsk_socket_config socket_config = gen_socket_config();
> const struct xsk_umem_config umem_config = {
> .fill_size = XSK_RING_PROD__DEFAULT_NUM_DESCS,
> .comp_size = XSK_RING_CONS__DEFAULT_NUM_DESCS,
> @@ -263,11 +274,14 @@ static int verify_metadata(struct xsk *rx_xsk, int rxq, int server_fd, clockid_t
> verify_skb_metadata(server_fd);
>
> for (i = 0; i < rxq; i++) {
> + bool first_seg = true;
> + bool is_eop = true;
> +
> if (fds[i].revents == 0)
> continue;
>
> struct xsk *xsk = &rx_xsk[i];
> -
> +peek:
> ret = xsk_ring_cons__peek(&xsk->rx, 1, &idx);
> printf("xsk_ring_cons__peek: %d\n", ret);
> if (ret != 1)
> @@ -276,12 +290,19 @@ static int verify_metadata(struct xsk *rx_xsk, int rxq, int server_fd, clockid_t
> rx_desc = xsk_ring_cons__rx_desc(&xsk->rx, idx);
> comp_addr = xsk_umem__extract_addr(rx_desc->addr);
> addr = xsk_umem__add_offset_to_addr(rx_desc->addr);
> - printf("%p: rx_desc[%u]->addr=%llx addr=%llx comp_addr=%llx\n",
> - xsk, idx, rx_desc->addr, addr, comp_addr);
> - verify_xdp_metadata(xsk_umem__get_data(xsk->umem_area, addr),
> - clock_id);
> + is_eop = !(rx_desc->options & XDP_PKT_CONTD);
> + printf("%p: rx_desc[%u]->addr=%llx addr=%llx comp_addr=%llx%s\n",
> + xsk, idx, rx_desc->addr, addr, comp_addr, is_eop ? " EoP" : "");
> + if (first_seg) {
> + verify_xdp_metadata(xsk_umem__get_data(xsk->umem_area, addr),
> + clock_id);
> + first_seg = false;
> + }
> +
> xsk_ring_cons__release(&xsk->rx, 1);
> refill_rx(xsk, comp_addr);
> + if (!is_eop)
> + goto peek;
> }
> }
>
> @@ -404,6 +425,54 @@ static void timestamping_enable(int fd, int val)
> error(1, errno, "setsockopt(SO_TIMESTAMPING)");
> }
>
> +static void print_usage(void)
> +{
> + const char *usage =
> + " Usage: xdp_hw_metadata [OPTIONS] [IFNAME]\n"
> + " Options:\n"
> + " -m Enable multi-buffer XDP for larger MTU\n"
> + " -h Display this help and exit\n\n"
> + " Generate test packets on the other machine with:\n"
> + " echo -n xdp | nc -u -q1 <dst_ip> 9091\n";
nit: any reason we have two spaces in the help description? I don't
think it's a standard practice, so maybe drop them?
On Mon, Oct 09, 2023 at 09:49:54AM -0700, Stanislav Fomichev wrote:
> On 10/09, Larysa Zaremba wrote:
> > This is a follow-up to the commit 9b2b86332a9b ("bpf: Allow to use kfunc
> > XDP hints and frags together").
> >
> > The are some possible implementations problems that may arise when
> > providing metadata specifically for multi-buffer packets, therefore there
> > must be a possibility to test such option separately.
> >
> > Add an option to use multi-buffer AF_XDP xdp_hw_metadata and mark used XDP
> > program as capable to use frags.
> >
> > As for now, xdp_hw_metadata accepts no options, so add simple option
> > parsing logic and a help message.
> >
> > For quick reference, also add an ingress packet generation command to the
> > help message. The command comes from [0].
> >
> > Example of output for multi-buffer packet:
> >
> > xsk_ring_cons__peek: 1
> > 0xead018: rx_desc[15]->addr=10000000000f000 addr=f100 comp_addr=f000
> > rx_hash: 0x5789FCBB with RSS type:0x29
> > rx_timestamp: 1696856851535324697 (sec:1696856851.5353)
> > XDP RX-time: 1696856843158256391 (sec:1696856843.1583)
> > delta sec:-8.3771 (-8377068.306 usec)
> > AF_XDP time: 1696856843158413078 (sec:1696856843.1584)
> > delta sec:0.0002 (156.687 usec)
> > 0xead018: complete idx=23 addr=f000
> > xsk_ring_cons__peek: 1
> > 0xead018: rx_desc[16]->addr=100000000008000 addr=8100 comp_addr=8000
> > 0xead018: complete idx=24 addr=8000
> > xsk_ring_cons__peek: 1
> > 0xead018: rx_desc[17]->addr=100000000009000 addr=9100 comp_addr=9000 EoP
> > 0xead018: complete idx=25 addr=9000
> >
> > Metadata is printed for the first packet only.
> >
> > [0] https://lore.kernel.org/all/[email protected]/
> >
> > Signed-off-by: Larysa Zaremba <[email protected]>
> > ---
> > .../selftests/bpf/progs/xdp_hw_metadata.c | 2 +-
> > tools/testing/selftests/bpf/xdp_hw_metadata.c | 92 ++++++++++++++++---
> > 2 files changed, 79 insertions(+), 15 deletions(-)
> >
> > diff --git a/tools/testing/selftests/bpf/progs/xdp_hw_metadata.c b/tools/testing/selftests/bpf/progs/xdp_hw_metadata.c
> > index 63d7de6c6bbb..8767d919c881 100644
> > --- a/tools/testing/selftests/bpf/progs/xdp_hw_metadata.c
> > +++ b/tools/testing/selftests/bpf/progs/xdp_hw_metadata.c
> > @@ -21,7 +21,7 @@ extern int bpf_xdp_metadata_rx_timestamp(const struct xdp_md *ctx,
> > extern int bpf_xdp_metadata_rx_hash(const struct xdp_md *ctx, __u32 *hash,
> > enum xdp_rss_hash_type *rss_type) __ksym;
> >
> > -SEC("xdp")
> > +SEC("xdp.frags")
> > int rx(struct xdp_md *ctx)
> > {
> > void *data, *data_meta, *data_end;
> > diff --git a/tools/testing/selftests/bpf/xdp_hw_metadata.c b/tools/testing/selftests/bpf/xdp_hw_metadata.c
> > index 17c980138796..25225720346b 100644
> > --- a/tools/testing/selftests/bpf/xdp_hw_metadata.c
> > +++ b/tools/testing/selftests/bpf/xdp_hw_metadata.c
> > @@ -26,6 +26,7 @@
> > #include <linux/sockios.h>
> > #include <sys/mman.h>
> > #include <net/if.h>
> > +#include <ctype.h>
> > #include <poll.h>
> > #include <time.h>
> >
> > @@ -49,19 +50,29 @@ struct xsk {
> > struct xdp_hw_metadata *bpf_obj;
> > struct xsk *rx_xsk;
> > const char *ifname;
> > +bool use_frags;
> > int ifindex;
> > int rxq;
> >
> > void test__fail(void) { /* for network_helpers.c */ }
> >
> > -static int open_xsk(int ifindex, struct xsk *xsk, __u32 queue_id)
> > +static struct xsk_socket_config gen_socket_config(void)
> > {
> > - int mmap_flags = MAP_PRIVATE | MAP_ANONYMOUS | MAP_NORESERVE;
> > - const struct xsk_socket_config socket_config = {
> > + struct xsk_socket_config socket_config = {
> > .rx_size = XSK_RING_PROD__DEFAULT_NUM_DESCS,
> > .tx_size = XSK_RING_PROD__DEFAULT_NUM_DESCS,
> > .bind_flags = XDP_COPY,
> > };
> > +
> > + if (use_frags)
> > + socket_config.bind_flags |= XDP_USE_SG;
> > + return socket_config;
> > +}
>
> nit: why not drop const from socket_config and add this 'if (use_frags)'
> directly to open_xsk? Not sure separate function really buys us anything?
>
Considering there will also be ZC/copy option, I thought it would be good to
separate socket config creation. After giving this a sencond thought though,
for now options would control bind_flags only. What do you this about removing
gen_socket_config(), but introducing get_bind_flags()?
> > +static int open_xsk(int ifindex, struct xsk *xsk, __u32 queue_id)
> > +{
> > + int mmap_flags = MAP_PRIVATE | MAP_ANONYMOUS | MAP_NORESERVE;
> > + struct xsk_socket_config socket_config = gen_socket_config();
> > const struct xsk_umem_config umem_config = {
> > .fill_size = XSK_RING_PROD__DEFAULT_NUM_DESCS,
> > .comp_size = XSK_RING_CONS__DEFAULT_NUM_DESCS,
> > @@ -263,11 +274,14 @@ static int verify_metadata(struct xsk *rx_xsk, int rxq, int server_fd, clockid_t
> > verify_skb_metadata(server_fd);
> >
> > for (i = 0; i < rxq; i++) {
> > + bool first_seg = true;
> > + bool is_eop = true;
> > +
> > if (fds[i].revents == 0)
> > continue;
> >
> > struct xsk *xsk = &rx_xsk[i];
> > -
> > +peek:
> > ret = xsk_ring_cons__peek(&xsk->rx, 1, &idx);
> > printf("xsk_ring_cons__peek: %d\n", ret);
> > if (ret != 1)
> > @@ -276,12 +290,19 @@ static int verify_metadata(struct xsk *rx_xsk, int rxq, int server_fd, clockid_t
> > rx_desc = xsk_ring_cons__rx_desc(&xsk->rx, idx);
> > comp_addr = xsk_umem__extract_addr(rx_desc->addr);
> > addr = xsk_umem__add_offset_to_addr(rx_desc->addr);
> > - printf("%p: rx_desc[%u]->addr=%llx addr=%llx comp_addr=%llx\n",
> > - xsk, idx, rx_desc->addr, addr, comp_addr);
> > - verify_xdp_metadata(xsk_umem__get_data(xsk->umem_area, addr),
> > - clock_id);
> > + is_eop = !(rx_desc->options & XDP_PKT_CONTD);
> > + printf("%p: rx_desc[%u]->addr=%llx addr=%llx comp_addr=%llx%s\n",
> > + xsk, idx, rx_desc->addr, addr, comp_addr, is_eop ? " EoP" : "");
> > + if (first_seg) {
> > + verify_xdp_metadata(xsk_umem__get_data(xsk->umem_area, addr),
> > + clock_id);
> > + first_seg = false;
> > + }
> > +
> > xsk_ring_cons__release(&xsk->rx, 1);
> > refill_rx(xsk, comp_addr);
> > + if (!is_eop)
> > + goto peek;
> > }
> > }
> >
> > @@ -404,6 +425,54 @@ static void timestamping_enable(int fd, int val)
> > error(1, errno, "setsockopt(SO_TIMESTAMPING)");
> > }
> >
> > +static void print_usage(void)
> > +{
> > + const char *usage =
> > + " Usage: xdp_hw_metadata [OPTIONS] [IFNAME]\n"
> > + " Options:\n"
> > + " -m Enable multi-buffer XDP for larger MTU\n"
> > + " -h Display this help and exit\n\n"
> > + " Generate test packets on the other machine with:\n"
> > + " echo -n xdp | nc -u -q1 <dst_ip> 9091\n";
>
> nit: any reason we have two spaces in the help description? I don't
> think it's a standard practice, so maybe drop them?
I have just copied usage from xskxceiver. As I see, this is not a standard
practice indeed, will fix.
On 10/10, Larysa Zaremba wrote:
> On Mon, Oct 09, 2023 at 09:49:54AM -0700, Stanislav Fomichev wrote:
> > On 10/09, Larysa Zaremba wrote:
> > > This is a follow-up to the commit 9b2b86332a9b ("bpf: Allow to use kfunc
> > > XDP hints and frags together").
> > >
> > > The are some possible implementations problems that may arise when
> > > providing metadata specifically for multi-buffer packets, therefore there
> > > must be a possibility to test such option separately.
> > >
> > > Add an option to use multi-buffer AF_XDP xdp_hw_metadata and mark used XDP
> > > program as capable to use frags.
> > >
> > > As for now, xdp_hw_metadata accepts no options, so add simple option
> > > parsing logic and a help message.
> > >
> > > For quick reference, also add an ingress packet generation command to the
> > > help message. The command comes from [0].
> > >
> > > Example of output for multi-buffer packet:
> > >
> > > xsk_ring_cons__peek: 1
> > > 0xead018: rx_desc[15]->addr=10000000000f000 addr=f100 comp_addr=f000
> > > rx_hash: 0x5789FCBB with RSS type:0x29
> > > rx_timestamp: 1696856851535324697 (sec:1696856851.5353)
> > > XDP RX-time: 1696856843158256391 (sec:1696856843.1583)
> > > delta sec:-8.3771 (-8377068.306 usec)
> > > AF_XDP time: 1696856843158413078 (sec:1696856843.1584)
> > > delta sec:0.0002 (156.687 usec)
> > > 0xead018: complete idx=23 addr=f000
> > > xsk_ring_cons__peek: 1
> > > 0xead018: rx_desc[16]->addr=100000000008000 addr=8100 comp_addr=8000
> > > 0xead018: complete idx=24 addr=8000
> > > xsk_ring_cons__peek: 1
> > > 0xead018: rx_desc[17]->addr=100000000009000 addr=9100 comp_addr=9000 EoP
> > > 0xead018: complete idx=25 addr=9000
> > >
> > > Metadata is printed for the first packet only.
> > >
> > > [0] https://lore.kernel.org/all/[email protected]/
> > >
> > > Signed-off-by: Larysa Zaremba <[email protected]>
> > > ---
> > > .../selftests/bpf/progs/xdp_hw_metadata.c | 2 +-
> > > tools/testing/selftests/bpf/xdp_hw_metadata.c | 92 ++++++++++++++++---
> > > 2 files changed, 79 insertions(+), 15 deletions(-)
> > >
> > > diff --git a/tools/testing/selftests/bpf/progs/xdp_hw_metadata.c b/tools/testing/selftests/bpf/progs/xdp_hw_metadata.c
> > > index 63d7de6c6bbb..8767d919c881 100644
> > > --- a/tools/testing/selftests/bpf/progs/xdp_hw_metadata.c
> > > +++ b/tools/testing/selftests/bpf/progs/xdp_hw_metadata.c
> > > @@ -21,7 +21,7 @@ extern int bpf_xdp_metadata_rx_timestamp(const struct xdp_md *ctx,
> > > extern int bpf_xdp_metadata_rx_hash(const struct xdp_md *ctx, __u32 *hash,
> > > enum xdp_rss_hash_type *rss_type) __ksym;
> > >
> > > -SEC("xdp")
> > > +SEC("xdp.frags")
> > > int rx(struct xdp_md *ctx)
> > > {
> > > void *data, *data_meta, *data_end;
> > > diff --git a/tools/testing/selftests/bpf/xdp_hw_metadata.c b/tools/testing/selftests/bpf/xdp_hw_metadata.c
> > > index 17c980138796..25225720346b 100644
> > > --- a/tools/testing/selftests/bpf/xdp_hw_metadata.c
> > > +++ b/tools/testing/selftests/bpf/xdp_hw_metadata.c
> > > @@ -26,6 +26,7 @@
> > > #include <linux/sockios.h>
> > > #include <sys/mman.h>
> > > #include <net/if.h>
> > > +#include <ctype.h>
> > > #include <poll.h>
> > > #include <time.h>
> > >
> > > @@ -49,19 +50,29 @@ struct xsk {
> > > struct xdp_hw_metadata *bpf_obj;
> > > struct xsk *rx_xsk;
> > > const char *ifname;
> > > +bool use_frags;
> > > int ifindex;
> > > int rxq;
> > >
> > > void test__fail(void) { /* for network_helpers.c */ }
> > >
> > > -static int open_xsk(int ifindex, struct xsk *xsk, __u32 queue_id)
> > > +static struct xsk_socket_config gen_socket_config(void)
> > > {
> > > - int mmap_flags = MAP_PRIVATE | MAP_ANONYMOUS | MAP_NORESERVE;
> > > - const struct xsk_socket_config socket_config = {
> > > + struct xsk_socket_config socket_config = {
> > > .rx_size = XSK_RING_PROD__DEFAULT_NUM_DESCS,
> > > .tx_size = XSK_RING_PROD__DEFAULT_NUM_DESCS,
> > > .bind_flags = XDP_COPY,
> > > };
> > > +
> > > + if (use_frags)
> > > + socket_config.bind_flags |= XDP_USE_SG;
> > > + return socket_config;
> > > +}
> >
> > nit: why not drop const from socket_config and add this 'if (use_frags)'
> > directly to open_xsk? Not sure separate function really buys us anything?
> >
>
> Considering there will also be ZC/copy option, I thought it would be good to
> separate socket config creation. After giving this a sencond thought though,
> for now options would control bind_flags only. What do you this about removing
> gen_socket_config(), but introducing get_bind_flags()?
In my pending series [0] I ended up adding bind_flags argument
to open_xsk. Maybe do the same here? This also lets you drop
global use_frags (if you move option parsing directly into main).
Or maybe add global bind_flags if you want to keep separate parsing
routine (read_args)? Doesn't seem like we get anything by storing
separate use_flags/use_copy and then construct bind_flags via extra
get_bind_flags()?
0: https://lore.kernel.org/bpf/[email protected]/
On Tue, Oct 10, 2023 at 09:04:47AM -0700, Stanislav Fomichev wrote:
> On 10/10, Larysa Zaremba wrote:
> > On Mon, Oct 09, 2023 at 09:49:54AM -0700, Stanislav Fomichev wrote:
> > > On 10/09, Larysa Zaremba wrote:
> > > > This is a follow-up to the commit 9b2b86332a9b ("bpf: Allow to use kfunc
> > > > XDP hints and frags together").
> > > >
> > > > The are some possible implementations problems that may arise when
> > > > providing metadata specifically for multi-buffer packets, therefore there
> > > > must be a possibility to test such option separately.
> > > >
> > > > Add an option to use multi-buffer AF_XDP xdp_hw_metadata and mark used XDP
> > > > program as capable to use frags.
> > > >
> > > > As for now, xdp_hw_metadata accepts no options, so add simple option
> > > > parsing logic and a help message.
> > > >
> > > > For quick reference, also add an ingress packet generation command to the
> > > > help message. The command comes from [0].
> > > >
> > > > Example of output for multi-buffer packet:
> > > >
> > > > xsk_ring_cons__peek: 1
> > > > 0xead018: rx_desc[15]->addr=10000000000f000 addr=f100 comp_addr=f000
> > > > rx_hash: 0x5789FCBB with RSS type:0x29
> > > > rx_timestamp: 1696856851535324697 (sec:1696856851.5353)
> > > > XDP RX-time: 1696856843158256391 (sec:1696856843.1583)
> > > > delta sec:-8.3771 (-8377068.306 usec)
> > > > AF_XDP time: 1696856843158413078 (sec:1696856843.1584)
> > > > delta sec:0.0002 (156.687 usec)
> > > > 0xead018: complete idx=23 addr=f000
> > > > xsk_ring_cons__peek: 1
> > > > 0xead018: rx_desc[16]->addr=100000000008000 addr=8100 comp_addr=8000
> > > > 0xead018: complete idx=24 addr=8000
> > > > xsk_ring_cons__peek: 1
> > > > 0xead018: rx_desc[17]->addr=100000000009000 addr=9100 comp_addr=9000 EoP
> > > > 0xead018: complete idx=25 addr=9000
> > > >
> > > > Metadata is printed for the first packet only.
> > > >
> > > > [0] https://lore.kernel.org/all/[email protected]/
> > > >
> > > > Signed-off-by: Larysa Zaremba <[email protected]>
> > > > ---
> > > > .../selftests/bpf/progs/xdp_hw_metadata.c | 2 +-
> > > > tools/testing/selftests/bpf/xdp_hw_metadata.c | 92 ++++++++++++++++---
> > > > 2 files changed, 79 insertions(+), 15 deletions(-)
> > > >
> > > > diff --git a/tools/testing/selftests/bpf/progs/xdp_hw_metadata.c b/tools/testing/selftests/bpf/progs/xdp_hw_metadata.c
> > > > index 63d7de6c6bbb..8767d919c881 100644
> > > > --- a/tools/testing/selftests/bpf/progs/xdp_hw_metadata.c
> > > > +++ b/tools/testing/selftests/bpf/progs/xdp_hw_metadata.c
> > > > @@ -21,7 +21,7 @@ extern int bpf_xdp_metadata_rx_timestamp(const struct xdp_md *ctx,
> > > > extern int bpf_xdp_metadata_rx_hash(const struct xdp_md *ctx, __u32 *hash,
> > > > enum xdp_rss_hash_type *rss_type) __ksym;
> > > >
> > > > -SEC("xdp")
> > > > +SEC("xdp.frags")
> > > > int rx(struct xdp_md *ctx)
> > > > {
> > > > void *data, *data_meta, *data_end;
> > > > diff --git a/tools/testing/selftests/bpf/xdp_hw_metadata.c b/tools/testing/selftests/bpf/xdp_hw_metadata.c
> > > > index 17c980138796..25225720346b 100644
> > > > --- a/tools/testing/selftests/bpf/xdp_hw_metadata.c
> > > > +++ b/tools/testing/selftests/bpf/xdp_hw_metadata.c
> > > > @@ -26,6 +26,7 @@
> > > > #include <linux/sockios.h>
> > > > #include <sys/mman.h>
> > > > #include <net/if.h>
> > > > +#include <ctype.h>
> > > > #include <poll.h>
> > > > #include <time.h>
> > > >
> > > > @@ -49,19 +50,29 @@ struct xsk {
> > > > struct xdp_hw_metadata *bpf_obj;
> > > > struct xsk *rx_xsk;
> > > > const char *ifname;
> > > > +bool use_frags;
> > > > int ifindex;
> > > > int rxq;
> > > >
> > > > void test__fail(void) { /* for network_helpers.c */ }
> > > >
> > > > -static int open_xsk(int ifindex, struct xsk *xsk, __u32 queue_id)
> > > > +static struct xsk_socket_config gen_socket_config(void)
> > > > {
> > > > - int mmap_flags = MAP_PRIVATE | MAP_ANONYMOUS | MAP_NORESERVE;
> > > > - const struct xsk_socket_config socket_config = {
> > > > + struct xsk_socket_config socket_config = {
> > > > .rx_size = XSK_RING_PROD__DEFAULT_NUM_DESCS,
> > > > .tx_size = XSK_RING_PROD__DEFAULT_NUM_DESCS,
> > > > .bind_flags = XDP_COPY,
> > > > };
> > > > +
> > > > + if (use_frags)
> > > > + socket_config.bind_flags |= XDP_USE_SG;
> > > > + return socket_config;
> > > > +}
> > >
> > > nit: why not drop const from socket_config and add this 'if (use_frags)'
> > > directly to open_xsk? Not sure separate function really buys us anything?
> > >
> >
> > Considering there will also be ZC/copy option, I thought it would be good to
> > separate socket config creation. After giving this a sencond thought though,
> > for now options would control bind_flags only. What do you this about removing
> > gen_socket_config(), but introducing get_bind_flags()?
>
> In my pending series [0] I ended up adding bind_flags argument
> to open_xsk. Maybe do the same here? This also lets you drop
> global use_frags (if you move option parsing directly into main).
>
> Or maybe add global bind_flags if you want to keep separate parsing
> routine (read_args)? Doesn't seem like we get anything by storing
> separate use_flags/use_copy and then construct bind_flags via extra
> get_bind_flags()?
>
I like the option with global bind_flags.
> 0: https://lore.kernel.org/bpf/[email protected]/