summaryrefslogtreecommitdiff
path: root/samples
diff options
context:
space:
mode:
authorDavid S. Miller <davem@davemloft.net>2021-07-15 22:40:10 -0700
committerDavid S. Miller <davem@davemloft.net>2021-07-15 22:40:10 -0700
commit82a1ffe57ec6455658584459de56ee4b401c1dfb (patch)
tree66fd801e94825018e15701e508848b6a188bf2c6 /samples
parent87117baf4f923a44bab189c37a6c8783f0c03525 (diff)
parentc50524ec4e3ad97d7d963268abd859c6413fbeb4 (diff)
Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Alexei Starovoitov says: ==================== pull-request: bpf-next 2021-07-15 The following pull-request contains BPF updates for your *net-next* tree. We've added 45 non-merge commits during the last 15 day(s) which contain a total of 52 files changed, 3122 insertions(+), 384 deletions(-). The main changes are: 1) Introduce bpf timers, from Alexei. 2) Add sockmap support for unix datagram socket, from Cong. 3) Fix potential memleak and UAF in the verifier, from He. 4) Add bpf_get_func_ip helper, from Jiri. 5) Improvements to generic XDP mode, from Kumar. 6) Support for passing xdp_md to XDP programs in bpf_prog_run, from Zvi. =================== Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'samples')
-rw-r--r--samples/bpf/xdp_redirect_cpu_user.c22
1 files changed, 16 insertions, 6 deletions
diff --git a/samples/bpf/xdp_redirect_cpu_user.c b/samples/bpf/xdp_redirect_cpu_user.c
index 576411612523..d3ecdc18b9c1 100644
--- a/samples/bpf/xdp_redirect_cpu_user.c
+++ b/samples/bpf/xdp_redirect_cpu_user.c
@@ -792,13 +792,23 @@ int main(int argc, char **argv)
n_cpus = get_nprocs_conf();
- /* Notice: choosing he queue size is very important with the
- * ixgbe driver, because it's driver page recycling trick is
- * dependend on pages being returned quickly. The number of
- * out-standing packets in the system must be less-than 2x
- * RX-ring size.
+ /* Notice: Choosing the queue size is very important when CPU is
+ * configured with power-saving states.
+ *
+ * If deepest state take 133 usec to wakeup from (133/10^6). When link
+ * speed is 10Gbit/s ((10*10^9/8) in bytes/sec). How many bytes can
+ * arrive with in 133 usec at this speed: (10*10^9/8)*(133/10^6) =
+ * 166250 bytes. With MTU size packets this is 110 packets, and with
+ * minimum Ethernet (MAC-preamble + intergap) 84 bytes is 1979 packets.
+ *
+ * Setting default cpumap queue to 2048 as worst-case (small packet)
+ * should be +64 packet due kthread wakeup call (due to xdp_do_flush)
+ * worst-case is 2043 packets.
+ *
+ * Sysadm can configured system to avoid deep-sleep via:
+ * tuned-adm profile network-latency
*/
- qsize = 128+64;
+ qsize = 2048;
snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
prog_load_attr.file = filename;