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authorCiara Loftus <ciara.loftus@intel.com>2020-10-02 13:36:12 +0000
committerAlexei Starovoitov <ast@kernel.org>2020-10-06 11:46:50 -0700
commit67ed375530e223624508382a9348a21c3b2ccc09 (patch)
tree1afad1359b572a061f5c0ad49969fcc2e6b7fb17
parent60dc609dbd545226e00c9e7b518d0f4873f0a3e1 (diff)
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samples: bpf: Driver interrupt statistics in xdpsock
Add an option to count the number of interrupts generated per second and total number of interrupts during the lifetime of the application for a given interface. This information is extracted from /proc/interrupts. Since there is no naming convention across drivers, the user must provide the string which is specific to their interface in the /proc/interrupts file on the command line. Usage: ./xdpsock ... -I <irq_str> eg. for queue 0 of i40e device eth0: ./xdpsock ... -I i40e-eth0-TxRx-0 Signed-off-by: Ciara Loftus <ciara.loftus@intel.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20201002133612.31536-3-ciara.loftus@intel.com
-rw-r--r--samples/bpf/xdpsock_user.c120
1 files changed, 119 insertions, 1 deletions
diff --git a/samples/bpf/xdpsock_user.c b/samples/bpf/xdpsock_user.c
index ff119ede4ab1..1149e94ca32f 100644
--- a/samples/bpf/xdpsock_user.c
+++ b/samples/bpf/xdpsock_user.c
@@ -11,6 +11,7 @@
#include <linux/if_xdp.h>
#include <linux/if_ether.h>
#include <linux/ip.h>
+#include <linux/limits.h>
#include <linux/udp.h>
#include <arpa/inet.h>
#include <locale.h>
@@ -80,6 +81,9 @@ static u32 opt_pkt_fill_pattern = 0x12345678;
static bool opt_extra_stats;
static bool opt_quiet;
static bool opt_app_stats;
+static const char *opt_irq_str = "";
+static u32 irq_no;
+static int irqs_at_init = -1;
static int opt_poll;
static int opt_interval = 1;
static u32 opt_xdp_bind_flags = XDP_USE_NEED_WAKEUP;
@@ -111,6 +115,11 @@ struct xsk_ring_stats {
unsigned long prev_tx_empty_npkts;
};
+struct xsk_driver_stats {
+ unsigned long intrs;
+ unsigned long prev_intrs;
+};
+
struct xsk_app_stats {
unsigned long rx_empty_polls;
unsigned long fill_fail_polls;
@@ -138,6 +147,7 @@ struct xsk_socket_info {
struct xsk_socket *xsk;
struct xsk_ring_stats ring_stats;
struct xsk_app_stats app_stats;
+ struct xsk_driver_stats drv_stats;
u32 outstanding_tx;
};
@@ -243,6 +253,100 @@ static void dump_app_stats(long dt)
}
}
+static bool get_interrupt_number(void)
+{
+ FILE *f_int_proc;
+ char line[4096];
+ bool found = false;
+
+ f_int_proc = fopen("/proc/interrupts", "r");
+ if (f_int_proc == NULL) {
+ printf("Failed to open /proc/interrupts.\n");
+ return found;
+ }
+
+ while (!feof(f_int_proc) && !found) {
+ /* Make sure to read a full line at a time */
+ if (fgets(line, sizeof(line), f_int_proc) == NULL ||
+ line[strlen(line) - 1] != '\n') {
+ printf("Error reading from interrupts file\n");
+ break;
+ }
+
+ /* Extract interrupt number from line */
+ if (strstr(line, opt_irq_str) != NULL) {
+ irq_no = atoi(line);
+ found = true;
+ break;
+ }
+ }
+
+ fclose(f_int_proc);
+
+ return found;
+}
+
+static int get_irqs(void)
+{
+ char count_path[PATH_MAX];
+ int total_intrs = -1;
+ FILE *f_count_proc;
+ char line[4096];
+
+ snprintf(count_path, sizeof(count_path),
+ "/sys/kernel/irq/%i/per_cpu_count", irq_no);
+ f_count_proc = fopen(count_path, "r");
+ if (f_count_proc == NULL) {
+ printf("Failed to open %s\n", count_path);
+ return total_intrs;
+ }
+
+ if (fgets(line, sizeof(line), f_count_proc) == NULL ||
+ line[strlen(line) - 1] != '\n') {
+ printf("Error reading from %s\n", count_path);
+ } else {
+ static const char com[2] = ",";
+ char *token;
+
+ total_intrs = 0;
+ token = strtok(line, com);
+ while (token != NULL) {
+ /* sum up interrupts across all cores */
+ total_intrs += atoi(token);
+ token = strtok(NULL, com);
+ }
+ }
+
+ fclose(f_count_proc);
+
+ return total_intrs;
+}
+
+static void dump_driver_stats(long dt)
+{
+ int i;
+
+ for (i = 0; i < num_socks && xsks[i]; i++) {
+ char *fmt = "%-18s %'-14.0f %'-14lu\n";
+ double intrs_ps;
+ int n_ints = get_irqs();
+
+ if (n_ints < 0) {
+ printf("error getting intr info for intr %i\n", irq_no);
+ return;
+ }
+ xsks[i]->drv_stats.intrs = n_ints - irqs_at_init;
+
+ intrs_ps = (xsks[i]->drv_stats.intrs - xsks[i]->drv_stats.prev_intrs) *
+ 1000000000. / dt;
+
+ printf("\n%-18s %-14s %-14s\n", "", "intrs/s", "count");
+ printf(fmt, "irqs", intrs_ps, xsks[i]->drv_stats.intrs);
+
+ xsks[i]->drv_stats.prev_intrs = xsks[i]->drv_stats.intrs;
+ }
+}
+
static void dump_stats(void)
{
unsigned long now = get_nsecs();
@@ -327,6 +431,8 @@ static void dump_stats(void)
if (opt_app_stats)
dump_app_stats(dt);
+ if (irq_no)
+ dump_driver_stats(dt);
}
static bool is_benchmark_done(void)
@@ -804,6 +910,7 @@ static struct option long_options[] = {
{"extra-stats", no_argument, 0, 'x'},
{"quiet", no_argument, 0, 'Q'},
{"app-stats", no_argument, 0, 'a'},
+ {"irq-string", no_argument, 0, 'I'},
{0, 0, 0, 0}
};
@@ -841,6 +948,7 @@ static void usage(const char *prog)
" -x, --extra-stats Display extra statistics.\n"
" -Q, --quiet Do not display any stats.\n"
" -a, --app-stats Display application (syscall) statistics.\n"
+ " -I, --irq-string Display driver interrupt statistics for interface associated with irq-string.\n"
"\n";
fprintf(stderr, str, prog, XSK_UMEM__DEFAULT_FRAME_SIZE,
opt_batch_size, MIN_PKT_SIZE, MIN_PKT_SIZE,
@@ -856,7 +964,7 @@ static void parse_command_line(int argc, char **argv)
opterr = 0;
for (;;) {
- c = getopt_long(argc, argv, "Frtli:q:pSNn:czf:muMd:b:C:s:P:xQa",
+ c = getopt_long(argc, argv, "Frtli:q:pSNn:czf:muMd:b:C:s:P:xQaI:",
long_options, &option_index);
if (c == -1)
break;
@@ -946,6 +1054,16 @@ static void parse_command_line(int argc, char **argv)
case 'a':
opt_app_stats = 1;
break;
+ case 'I':
+ opt_irq_str = optarg;
+ if (get_interrupt_number())
+ irqs_at_init = get_irqs();
+ if (irqs_at_init < 0) {
+ fprintf(stderr, "ERROR: Failed to get irqs for %s\n", opt_irq_str);
+ usage(basename(argv[0]));
+ }
+
+ break;
default:
usage(basename(argv[0]));
}