[PATCH bpf-next v4 07/22] samples: bpf: Add xdp_exception tracepoint statistics support
From: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Date: 2021-08-21 00:20:43
Also in:
netdev
Subsystem:
bpf [general] (safe dynamic programs and tools), the rest, xdp (express data path) · Maintainers:
Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Eduard Zingerman, Kumar Kartikeya Dwivedi, Linus Torvalds, David S. Miller, Jakub Kicinski, Jesper Dangaard Brouer, John Fastabend
This implements the retrieval and printing, as well the help output. Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> --- samples/bpf/xdp_sample_user.c | 113 ++++++++++++++++++++++++++++++++++ samples/bpf/xdp_sample_user.h | 3 + 2 files changed, 116 insertions(+)
diff --git a/samples/bpf/xdp_sample_user.c b/samples/bpf/xdp_sample_user.c
index c34592566825..52a30fd1f2a3 100644
--- a/samples/bpf/xdp_sample_user.c
+++ b/samples/bpf/xdp_sample_user.c@@ -74,6 +74,7 @@ enum map_type { MAP_RX, MAP_REDIRECT_ERR, + MAP_EXCEPTION, NUM_MAP, };
@@ -98,6 +99,7 @@ struct map_entry { struct stats_record { struct record rx_cnt; struct record redir_err[XDP_REDIRECT_ERR_MAX]; + struct record exception[XDP_ACTION_MAX]; }; struct sample_output {
@@ -115,6 +117,9 @@ struct sample_output { __u64 suc; __u64 err; } redir_cnt; + struct { + __u64 hits; + } except_cnt; }; struct xdp_desc {
@@ -156,6 +161,15 @@ static const char *xdp_redirect_err_help[XDP_REDIRECT_ERR_MAX - 1] = { "No space in ptr_ring of cpumap kthread", }; +static const char *xdp_action_names[XDP_ACTION_MAX] = { + [XDP_ABORTED] = "XDP_ABORTED", + [XDP_DROP] = "XDP_DROP", + [XDP_PASS] = "XDP_PASS", + [XDP_TX] = "XDP_TX", + [XDP_REDIRECT] = "XDP_REDIRECT", + [XDP_UNKNOWN] = "XDP_UNKNOWN", +}; + static __u64 gettime(void) { struct timespec t;
@@ -169,6 +183,13 @@ static __u64 gettime(void) return (__u64)t.tv_sec * NANOSEC_PER_SEC + t.tv_nsec; } +static const char *action2str(int action) +{ + if (action < XDP_ACTION_MAX) + return xdp_action_names[action]; + return NULL; +} + static void sample_print_help(int mask) { printf("Output format description\n\n"
@@ -206,6 +227,15 @@ static void sample_print_help(int mask) printf(" \n\t\t\t\terror/s - Packets that failed redirection per second\n\n"); } + + if (mask & SAMPLE_EXCEPTION_CNT) { + printf(" xdp_exception\t\tDisplays xdp_exception tracepoint events\n" + " \t\t\tThis can occur due to internal driver errors, unrecognized\n" + " \t\t\tXDP actions and due to explicit user trigger by use of XDP_ABORTED\n" + " \t\t\tEach action is expanded below this field with its count\n" + " \t\t\t\thit/s - Number of times the tracepoint was hit per second\n\n"); + } + } void sample_usage(char *argv[], const struct option *long_options,
@@ -327,9 +357,26 @@ static struct stats_record *alloc_stats_record(void) } } } + if (sample_mask & SAMPLE_EXCEPTION_CNT) { + for (i = 0; i < XDP_ACTION_MAX; i++) { + rec->exception[i].cpu = alloc_record_per_cpu(); + if (!rec->exception[i].cpu) { + fprintf(stderr, + "Failed to allocate exception per-CPU array for " + "\"%s\" case\n", + action2str(i)); + while (i--) + free(rec->exception[i].cpu); + goto end_redir; + } + } + } return rec; +end_redir: + for (i = 0; i < XDP_REDIRECT_ERR_MAX; i++) + free(rec->redir_err[i].cpu); end_rx_cnt: free(rec->rx_cnt.cpu); end_rec:
@@ -343,6 +390,8 @@ static void free_stats_record(struct stats_record *r) struct map_entry *e; int i; + for (i = 0; i < XDP_ACTION_MAX; i++) + free(r->exception[i].cpu); for (i = 0; i < XDP_REDIRECT_ERR_MAX; i++) free(r->redir_err[i].cpu); free(r->rx_cnt.cpu);
@@ -551,6 +600,50 @@ static void stats_get_redirect_err_cnt(struct stats_record *stats_rec, } } +static void stats_get_exception_cnt(struct stats_record *stats_rec, + struct stats_record *stats_prev, + unsigned int nr_cpus, + struct sample_output *out) +{ + double t, drop, sum = 0; + struct record *rec, *prev; + int rec_i, i; + + for (rec_i = 0; rec_i < XDP_ACTION_MAX; rec_i++) { + rec = &stats_rec->exception[rec_i]; + prev = &stats_prev->exception[rec_i]; + t = calc_period(rec, prev); + + drop = calc_drop_pps(&rec->total, &prev->total, t); + /* Fold out errors after heading */ + sum += drop; + + if (drop > 0 && !out) { + print_always(" %-18s " FMT_COLUMNf "\n", + action2str(rec_i), ERR(drop)); + + for (i = 0; i < nr_cpus; i++) { + struct datarec *r = &rec->cpu[i]; + struct datarec *p = &prev->cpu[i]; + char str[64]; + double drop; + + drop = calc_drop_pps(r, p, t); + if (!drop) + continue; + + snprintf(str, sizeof(str), "cpu:%d", i); + print_default(" %-16s" FMT_COLUMNf "\n", + str, ERR(drop)); + } + } + } + + if (out) { + out->except_cnt.hits = sum; + out->totals.err += sum; + } +} static void stats_print(const char *prefix, int mask, struct stats_record *r, struct stats_record *p, struct sample_output *out)
@@ -595,6 +688,16 @@ static void stats_print(const char *prefix, int mask, struct stats_record *r, stats_get_redirect_err_cnt(r, p, nr_cpus, NULL); } + if (mask & SAMPLE_EXCEPTION_CNT) { + str = out->except_cnt.hits ? "xdp_exception total" : + "xdp_exception"; + + print_err(out->except_cnt.hits, " %-20s " FMT_COLUMNl "\n", str, + HITS(out->except_cnt.hits)); + + stats_get_exception_cnt(r, p, nr_cpus, NULL); + } + if (sample_log_level & LL_DEFAULT || ((sample_log_level & LL_SIMPLE) && sample_err_exp)) { sample_err_exp = false;
@@ -617,6 +720,9 @@ int sample_setup_maps(struct bpf_map **maps) sample_map_count[i] = XDP_REDIRECT_ERR_MAX * sample_n_cpus; break; + case MAP_EXCEPTION: + sample_map_count[i] = XDP_ACTION_MAX * sample_n_cpus; + break; default: return -EINVAL; }
@@ -788,6 +894,11 @@ static int sample_stats_collect(struct stats_record *rec) &rec->redir_err[i]); } + if (sample_mask & SAMPLE_EXCEPTION_CNT) + for (i = 0; i < XDP_ACTION_MAX; i++) + map_collect_percpu(&sample_mmap[MAP_EXCEPTION][i * sample_n_cpus], + &rec->exception[i]); + return 0; }
@@ -811,6 +922,8 @@ static void sample_stats_print(int mask, struct stats_record *cur, stats_get_redirect_cnt(cur, prev, 0, &out); if (mask & SAMPLE_REDIRECT_ERR_CNT) stats_get_redirect_err_cnt(cur, prev, 0, &out); + if (mask & SAMPLE_EXCEPTION_CNT) + stats_get_exception_cnt(cur, prev, 0, &out); sample_summary_update(&out, interval); stats_print(prog_name, mask, cur, prev, &out);
diff --git a/samples/bpf/xdp_sample_user.h b/samples/bpf/xdp_sample_user.h
index 1935a0e2f85b..aa28e4bdd628 100644
--- a/samples/bpf/xdp_sample_user.h
+++ b/samples/bpf/xdp_sample_user.h@@ -11,6 +11,7 @@ enum stats_mask { _SAMPLE_REDIRECT_MAP = 1U << 0, SAMPLE_RX_CNT = 1U << 1, SAMPLE_REDIRECT_ERR_CNT = 1U << 2, + SAMPLE_EXCEPTION_CNT = 1U << 5, SAMPLE_REDIRECT_CNT = 1U << 7, SAMPLE_REDIRECT_MAP_CNT = SAMPLE_REDIRECT_CNT | _SAMPLE_REDIRECT_MAP, SAMPLE_REDIRECT_ERR_MAP_CNT = SAMPLE_REDIRECT_ERR_CNT | _SAMPLE_REDIRECT_MAP,
@@ -75,6 +76,8 @@ static inline char *safe_strncpy(char *dst, const char *src, size_t size) __attach_tp(tp_xdp_redirect_map_err); \ if (mask & SAMPLE_REDIRECT_ERR_CNT) \ __attach_tp(tp_xdp_redirect_err); \ + if (mask & SAMPLE_EXCEPTION_CNT) \ + __attach_tp(tp_xdp_exception); \ return 0; \ }
--
2.33.0