From fa24d0b1d57825d1a5b802339728d4d8ac20b6d6 Mon Sep 17 00:00:00 2001 From: Ong Boon Leong Date: Thu, 30 Dec 2021 11:54:45 +0800 Subject: samples/bpf: xdpsock: Add sched policy and priority support By default, TX schedule policy is SCHED_OTHER (round-robin time-sharing). To improve TX cyclic scheduling, we add SCHED_FIFO policy and its priority by using -W FIFO or --policy=FIFO and -U or --schpri=. A) From xdpsock --app-stats, for SCHED_OTHER policy: $ xdpsock -i eth0 -t -N -z -T 1000 -b 16 -C 100000 -a period min ave max cycle Cyclic TX 1000000 53507 75334 712642 6250 B) For SCHED_FIFO policy and schpri=50: $ xdpsock -i eth0 -t -N -z -T 1000 -b 16 -C 100000 -a -W FIFO -U 50 period min ave max cycle Cyclic TX 1000000 3699 24859 54397 6250 Signed-off-by: Ong Boon Leong Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20211230035447.523177-6-boon.leong.ong@intel.com --- samples/bpf/xdpsock_user.c | 61 ++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 59 insertions(+), 2 deletions(-) (limited to 'samples') diff --git a/samples/bpf/xdpsock_user.c b/samples/bpf/xdpsock_user.c index a2a42ec4b0e9..b7d0f536f974 100644 --- a/samples/bpf/xdpsock_user.c +++ b/samples/bpf/xdpsock_user.c @@ -31,6 +31,7 @@ #include #include #include +#include #include #include @@ -66,6 +67,8 @@ #define NSEC_PER_SEC 1000000000UL #define NSEC_PER_USEC 1000 +#define SCHED_PRI__DEFAULT 0 + typedef __u64 u64; typedef __u32 u32; typedef __u16 u16; @@ -123,6 +126,8 @@ static bool opt_busy_poll; static bool opt_reduced_cap; static clockid_t opt_clock = CLOCK_MONOTONIC; static unsigned long opt_tx_cycle_ns; +static int opt_schpolicy = SCHED_OTHER; +static int opt_schprio = SCHED_PRI__DEFAULT; struct vlan_ethhdr { unsigned char h_dest[6]; @@ -198,6 +203,15 @@ static const struct clockid_map { { NULL } }; +static const struct sched_map { + const char *name; + int policy; +} schmap[] = { + { "OTHER", SCHED_OTHER }, + { "FIFO", SCHED_FIFO }, + { NULL } +}; + static int num_socks; struct xsk_socket_info *xsks[MAX_SOCKS]; int sock; @@ -216,6 +230,20 @@ static int get_clockid(clockid_t *id, const char *name) return -1; } +static int get_schpolicy(int *policy, const char *name) +{ + const struct sched_map *sch; + + for (sch = schmap; sch->name; sch++) { + if (strcasecmp(sch->name, name) == 0) { + *policy = sch->policy; + return 0; + } + } + + return -1; +} + static unsigned long get_nsecs(void) { struct timespec ts; @@ -1019,6 +1047,8 @@ static struct option long_options[] = { {"tx-dmac", required_argument, 0, 'G'}, {"tx-smac", required_argument, 0, 'H'}, {"tx-cycle", required_argument, 0, 'T'}, + {"policy", required_argument, 0, 'W'}, + {"schpri", required_argument, 0, 'U'}, {"extra-stats", no_argument, 0, 'x'}, {"quiet", no_argument, 0, 'Q'}, {"app-stats", no_argument, 0, 'a'}, @@ -1066,6 +1096,8 @@ static void usage(const char *prog) " -G, --tx-dmac= Dest MAC addr of TX frame in aa:bb:cc:dd:ee:ff format (For -V|--tx-vlan)\n" " -H, --tx-smac= Src MAC addr of TX frame in aa:bb:cc:dd:ee:ff format (For -V|--tx-vlan)\n" " -T, --tx-cycle=n Tx cycle time in micro-seconds (For -t|--txonly).\n" + " -W, --policy=POLICY Schedule policy. Default: SCHED_OTHER\n" + " -U, --schpri=n Schedule priority. Default: %d\n" " -x, --extra-stats Display extra statistics.\n" " -Q, --quiet Do not display any stats.\n" " -a, --app-stats Display application (syscall) statistics.\n" @@ -1076,7 +1108,8 @@ static void usage(const char *prog) fprintf(stderr, str, prog, XSK_UMEM__DEFAULT_FRAME_SIZE, opt_batch_size, MIN_PKT_SIZE, MIN_PKT_SIZE, XSK_UMEM__DEFAULT_FRAME_SIZE, opt_pkt_fill_pattern, - VLAN_VID__DEFAULT, VLAN_PRI__DEFAULT); + VLAN_VID__DEFAULT, VLAN_PRI__DEFAULT, + SCHED_PRI__DEFAULT); exit(EXIT_FAILURE); } @@ -1088,7 +1121,8 @@ static void parse_command_line(int argc, char **argv) opterr = 0; for (;;) { - c = getopt_long(argc, argv, "Frtli:q:pSNn:w:czf:muMd:b:C:s:P:VJ:K:G:H:T:xQaI:BR", + c = getopt_long(argc, argv, + "Frtli:q:pSNn:w:czf:muMd:b:C:s:P:VJ:K:G:H:T:W:U:xQaI:BR", long_options, &option_index); if (c == -1) break; @@ -1206,6 +1240,17 @@ static void parse_command_line(int argc, char **argv) opt_tx_cycle_ns = atoi(optarg); opt_tx_cycle_ns *= NSEC_PER_USEC; break; + case 'W': + if (get_schpolicy(&opt_schpolicy, optarg)) { + fprintf(stderr, + "ERROR: Invalid policy %s. Default to SCHED_OTHER.\n", + optarg); + opt_schpolicy = SCHED_OTHER; + } + break; + case 'U': + opt_schprio = atoi(optarg); + break; case 'x': opt_extra_stats = 1; break; @@ -1780,6 +1825,7 @@ int main(int argc, char **argv) struct __user_cap_data_struct data[2] = { { 0 } }; struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY}; bool rx = false, tx = false; + struct sched_param schparam; struct xsk_umem_info *umem; struct bpf_object *obj; int xsks_map_fd = 0; @@ -1881,6 +1927,16 @@ int main(int argc, char **argv) prev_time = get_nsecs(); start_time = prev_time; + /* Configure sched priority for better wake-up accuracy */ + memset(&schparam, 0, sizeof(schparam)); + schparam.sched_priority = opt_schprio; + ret = sched_setscheduler(0, opt_schpolicy, &schparam); + if (ret) { + fprintf(stderr, "Error(%d) in setting priority(%d): %s\n", + errno, opt_schprio, strerror(errno)); + goto out; + } + if (opt_bench == BENCH_RXDROP) rx_drop_all(); else if (opt_bench == BENCH_TXONLY) @@ -1888,6 +1944,7 @@ int main(int argc, char **argv) else l2fwd_all(); +out: benchmark_done = true; if (!opt_quiet) -- cgit v1.2.3-58-ga151