aboutsummaryrefslogtreecommitdiffstats
path: root/samples
diff options
context:
space:
mode:
authorToke Høiland-Jørgensen <toke@redhat.com>2019-12-16 12:07:42 +0100
committerAlexei Starovoitov <ast@kernel.org>2019-12-16 07:05:38 -0800
commitd50ecc46d18fa19ccf06e0c4d2ee8a050c665e3d (patch)
treeb60ffa2c725d450b8f336af5283ddc733ba8da21 /samples
parent450278977acbf494a20367c22fbb38729772d1fc (diff)
downloadchrome-platform-d50ecc46d18fa19ccf06e0c4d2ee8a050c665e3d.tar.gz
samples/bpf: Attach XDP programs in driver mode by default
When attaching XDP programs, userspace can set flags to request the attach mode (generic/SKB mode, driver mode or hw offloaded mode). If no such flags are requested, the kernel will attempt to attach in driver mode, and then silently fall back to SKB mode if this fails. The silent fallback is a major source of user confusion, as users will try to load a program on a device without XDP support, and instead of an error they will get the silent fallback behaviour, not notice, and then wonder why performance is not what they were expecting. In an attempt to combat this, let's switch all the samples to default to explicitly requesting driver-mode attach. As part of this, ensure that all the userspace utilities have a switch to enable SKB mode. For those that have a switch to request driver mode, keep it but turn it into a no-op. Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Jesper Dangaard Brouer <brouer@redhat.com> Acked-by: David Ahern <dsahern@gmail.com> Link: https://lore.kernel.org/bpf/20191216110742.364456-1-toke@redhat.com
Diffstat (limited to 'samples')
-rw-r--r--samples/bpf/xdp1_user.c5
-rw-r--r--samples/bpf/xdp_adjust_tail_user.c5
-rw-r--r--samples/bpf/xdp_fwd_user.c17
-rw-r--r--samples/bpf/xdp_redirect_cpu_user.c4
-rw-r--r--samples/bpf/xdp_redirect_map_user.c5
-rw-r--r--samples/bpf/xdp_redirect_user.c5
-rw-r--r--samples/bpf/xdp_router_ipv4_user.c3
-rw-r--r--samples/bpf/xdp_rxq_info_user.c4
-rw-r--r--samples/bpf/xdp_sample_pkts_user.c12
-rw-r--r--samples/bpf/xdp_tx_iptunnel_user.c5
-rw-r--r--samples/bpf/xdpsock_user.c5
11 files changed, 58 insertions, 12 deletions
diff --git a/samples/bpf/xdp1_user.c b/samples/bpf/xdp1_user.c
index 3e553eed95a77a..38a8852cb57f51 100644
--- a/samples/bpf/xdp1_user.c
+++ b/samples/bpf/xdp1_user.c
@@ -98,7 +98,7 @@ int main(int argc, char **argv)
xdp_flags |= XDP_FLAGS_SKB_MODE;
break;
case 'N':
- xdp_flags |= XDP_FLAGS_DRV_MODE;
+ /* default, set below */
break;
case 'F':
xdp_flags &= ~XDP_FLAGS_UPDATE_IF_NOEXIST;
@@ -109,6 +109,9 @@ int main(int argc, char **argv)
}
}
+ if (!(xdp_flags & XDP_FLAGS_SKB_MODE))
+ xdp_flags |= XDP_FLAGS_DRV_MODE;
+
if (optind == argc) {
usage(basename(argv[0]));
return 1;
diff --git a/samples/bpf/xdp_adjust_tail_user.c b/samples/bpf/xdp_adjust_tail_user.c
index d86e9ad0356bd6..008789eb6adad0 100644
--- a/samples/bpf/xdp_adjust_tail_user.c
+++ b/samples/bpf/xdp_adjust_tail_user.c
@@ -120,7 +120,7 @@ int main(int argc, char **argv)
xdp_flags |= XDP_FLAGS_SKB_MODE;
break;
case 'N':
- xdp_flags |= XDP_FLAGS_DRV_MODE;
+ /* default, set below */
break;
case 'F':
xdp_flags &= ~XDP_FLAGS_UPDATE_IF_NOEXIST;
@@ -132,6 +132,9 @@ int main(int argc, char **argv)
opt_flags[opt] = 0;
}
+ if (!(xdp_flags & XDP_FLAGS_SKB_MODE))
+ xdp_flags |= XDP_FLAGS_DRV_MODE;
+
for (i = 0; i < strlen(optstr); i++) {
if (opt_flags[(unsigned int)optstr[i]]) {
fprintf(stderr, "Missing argument -%c\n", optstr[i]);
diff --git a/samples/bpf/xdp_fwd_user.c b/samples/bpf/xdp_fwd_user.c
index 97ff1dad766978..c30f9acfdb84dd 100644
--- a/samples/bpf/xdp_fwd_user.c
+++ b/samples/bpf/xdp_fwd_user.c
@@ -27,11 +27,13 @@
#include "libbpf.h"
#include <bpf/bpf.h>
+static __u32 xdp_flags = XDP_FLAGS_UPDATE_IF_NOEXIST;
+
static int do_attach(int idx, int prog_fd, int map_fd, const char *name)
{
int err;
- err = bpf_set_link_xdp_fd(idx, prog_fd, 0);
+ err = bpf_set_link_xdp_fd(idx, prog_fd, xdp_flags);
if (err < 0) {
printf("ERROR: failed to attach program to %s\n", name);
return err;
@@ -49,7 +51,7 @@ static int do_detach(int idx, const char *name)
{
int err;
- err = bpf_set_link_xdp_fd(idx, -1, 0);
+ err = bpf_set_link_xdp_fd(idx, -1, xdp_flags);
if (err < 0)
printf("ERROR: failed to detach program from %s\n", name);
@@ -83,11 +85,17 @@ int main(int argc, char **argv)
int attach = 1;
int ret = 0;
- while ((opt = getopt(argc, argv, ":dD")) != -1) {
+ while ((opt = getopt(argc, argv, ":dDSF")) != -1) {
switch (opt) {
case 'd':
attach = 0;
break;
+ case 'S':
+ xdp_flags |= XDP_FLAGS_SKB_MODE;
+ break;
+ case 'F':
+ xdp_flags &= ~XDP_FLAGS_UPDATE_IF_NOEXIST;
+ break;
case 'D':
prog_name = "xdp_fwd_direct";
break;
@@ -97,6 +105,9 @@ int main(int argc, char **argv)
}
}
+ if (!(xdp_flags & XDP_FLAGS_SKB_MODE))
+ xdp_flags |= XDP_FLAGS_DRV_MODE;
+
if (optind == argc) {
usage(basename(argv[0]));
return 1;
diff --git a/samples/bpf/xdp_redirect_cpu_user.c b/samples/bpf/xdp_redirect_cpu_user.c
index 0da6e9e7132ecd..72af628529b51f 100644
--- a/samples/bpf/xdp_redirect_cpu_user.c
+++ b/samples/bpf/xdp_redirect_cpu_user.c
@@ -728,6 +728,10 @@ int main(int argc, char **argv)
return EXIT_FAIL_OPTION;
}
}
+
+ if (!(xdp_flags & XDP_FLAGS_SKB_MODE))
+ xdp_flags |= XDP_FLAGS_DRV_MODE;
+
/* Required option */
if (ifindex == -1) {
fprintf(stderr, "ERR: required option --dev missing\n");
diff --git a/samples/bpf/xdp_redirect_map_user.c b/samples/bpf/xdp_redirect_map_user.c
index f70ee33907fde0..cc840661faabc9 100644
--- a/samples/bpf/xdp_redirect_map_user.c
+++ b/samples/bpf/xdp_redirect_map_user.c
@@ -116,7 +116,7 @@ int main(int argc, char **argv)
xdp_flags |= XDP_FLAGS_SKB_MODE;
break;
case 'N':
- xdp_flags |= XDP_FLAGS_DRV_MODE;
+ /* default, set below */
break;
case 'F':
xdp_flags &= ~XDP_FLAGS_UPDATE_IF_NOEXIST;
@@ -127,6 +127,9 @@ int main(int argc, char **argv)
}
}
+ if (!(xdp_flags & XDP_FLAGS_SKB_MODE))
+ xdp_flags |= XDP_FLAGS_DRV_MODE;
+
if (optind == argc) {
printf("usage: %s <IFNAME|IFINDEX>_IN <IFNAME|IFINDEX>_OUT\n", argv[0]);
return 1;
diff --git a/samples/bpf/xdp_redirect_user.c b/samples/bpf/xdp_redirect_user.c
index 5440cd620607fb..71dff8e3382a88 100644
--- a/samples/bpf/xdp_redirect_user.c
+++ b/samples/bpf/xdp_redirect_user.c
@@ -117,7 +117,7 @@ int main(int argc, char **argv)
xdp_flags |= XDP_FLAGS_SKB_MODE;
break;
case 'N':
- xdp_flags |= XDP_FLAGS_DRV_MODE;
+ /* default, set below */
break;
case 'F':
xdp_flags &= ~XDP_FLAGS_UPDATE_IF_NOEXIST;
@@ -128,6 +128,9 @@ int main(int argc, char **argv)
}
}
+ if (!(xdp_flags & XDP_FLAGS_SKB_MODE))
+ xdp_flags |= XDP_FLAGS_DRV_MODE;
+
if (optind == argc) {
printf("usage: %s <IFNAME|IFINDEX>_IN <IFNAME|IFINDEX>_OUT\n", argv[0]);
return 1;
diff --git a/samples/bpf/xdp_router_ipv4_user.c b/samples/bpf/xdp_router_ipv4_user.c
index 1469b66ebad1ec..fef286c5add2d8 100644
--- a/samples/bpf/xdp_router_ipv4_user.c
+++ b/samples/bpf/xdp_router_ipv4_user.c
@@ -662,6 +662,9 @@ int main(int ac, char **argv)
}
}
+ if (!(flags & XDP_FLAGS_SKB_MODE))
+ flags |= XDP_FLAGS_DRV_MODE;
+
if (optind == ac) {
usage(basename(argv[0]));
return 1;
diff --git a/samples/bpf/xdp_rxq_info_user.c b/samples/bpf/xdp_rxq_info_user.c
index 8fc3ad01de72c7..fc4983fd69590a 100644
--- a/samples/bpf/xdp_rxq_info_user.c
+++ b/samples/bpf/xdp_rxq_info_user.c
@@ -551,6 +551,10 @@ int main(int argc, char **argv)
return EXIT_FAIL_OPTION;
}
}
+
+ if (!(xdp_flags & XDP_FLAGS_SKB_MODE))
+ xdp_flags |= XDP_FLAGS_DRV_MODE;
+
/* Required option */
if (ifindex == -1) {
fprintf(stderr, "ERR: required option --dev missing\n");
diff --git a/samples/bpf/xdp_sample_pkts_user.c b/samples/bpf/xdp_sample_pkts_user.c
index a5760e8bf2c44a..8c1af1b7372d4c 100644
--- a/samples/bpf/xdp_sample_pkts_user.c
+++ b/samples/bpf/xdp_sample_pkts_user.c
@@ -52,13 +52,13 @@ static int do_detach(int idx, const char *name)
__u32 curr_prog_id = 0;
int err = 0;
- err = bpf_get_link_xdp_id(idx, &curr_prog_id, 0);
+ err = bpf_get_link_xdp_id(idx, &curr_prog_id, xdp_flags);
if (err) {
printf("bpf_get_link_xdp_id failed\n");
return err;
}
if (prog_id == curr_prog_id) {
- err = bpf_set_link_xdp_fd(idx, -1, 0);
+ err = bpf_set_link_xdp_fd(idx, -1, xdp_flags);
if (err < 0)
printf("ERROR: failed to detach prog from %s\n", name);
} else if (!curr_prog_id) {
@@ -115,7 +115,7 @@ int main(int argc, char **argv)
.prog_type = BPF_PROG_TYPE_XDP,
};
struct perf_buffer_opts pb_opts = {};
- const char *optstr = "F";
+ const char *optstr = "FS";
int prog_fd, map_fd, opt;
struct bpf_object *obj;
struct bpf_map *map;
@@ -127,12 +127,18 @@ int main(int argc, char **argv)
case 'F':
xdp_flags &= ~XDP_FLAGS_UPDATE_IF_NOEXIST;
break;
+ case 'S':
+ xdp_flags |= XDP_FLAGS_SKB_MODE;
+ break;
default:
usage(basename(argv[0]));
return 1;
}
}
+ if (!(xdp_flags & XDP_FLAGS_SKB_MODE))
+ xdp_flags |= XDP_FLAGS_DRV_MODE;
+
if (optind == argc) {
usage(basename(argv[0]));
return 1;
diff --git a/samples/bpf/xdp_tx_iptunnel_user.c b/samples/bpf/xdp_tx_iptunnel_user.c
index 2fe4c7f5ffe5e8..5f33b553003238 100644
--- a/samples/bpf/xdp_tx_iptunnel_user.c
+++ b/samples/bpf/xdp_tx_iptunnel_user.c
@@ -231,7 +231,7 @@ int main(int argc, char **argv)
xdp_flags |= XDP_FLAGS_SKB_MODE;
break;
case 'N':
- xdp_flags |= XDP_FLAGS_DRV_MODE;
+ /* default, set below */
break;
case 'F':
xdp_flags &= ~XDP_FLAGS_UPDATE_IF_NOEXIST;
@@ -243,6 +243,9 @@ int main(int argc, char **argv)
opt_flags[opt] = 0;
}
+ if (!(xdp_flags & XDP_FLAGS_SKB_MODE))
+ xdp_flags |= XDP_FLAGS_DRV_MODE;
+
for (i = 0; i < strlen(optstr); i++) {
if (opt_flags[(unsigned int)optstr[i]]) {
fprintf(stderr, "Missing argument -%c\n", optstr[i]);
diff --git a/samples/bpf/xdpsock_user.c b/samples/bpf/xdpsock_user.c
index a15480010828fb..e7829e5baaffdc 100644
--- a/samples/bpf/xdpsock_user.c
+++ b/samples/bpf/xdpsock_user.c
@@ -440,7 +440,7 @@ static void parse_command_line(int argc, char **argv)
opt_xdp_bind_flags |= XDP_COPY;
break;
case 'N':
- opt_xdp_flags |= XDP_FLAGS_DRV_MODE;
+ /* default, set below */
break;
case 'n':
opt_interval = atoi(optarg);
@@ -474,6 +474,9 @@ static void parse_command_line(int argc, char **argv)
}
}
+ if (!(opt_xdp_flags & XDP_FLAGS_SKB_MODE))
+ opt_xdp_flags |= XDP_FLAGS_DRV_MODE;
+
opt_ifindex = if_nametoindex(opt_if);
if (!opt_ifindex) {
fprintf(stderr, "ERROR: interface \"%s\" does not exist\n",