summaryrefslogtreecommitdiffstats
path: root/samples/bpf/tracex6_user.c
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
commit4352b8aee98005853aa63f57d6377282de17a33f (patch)
tree27614d7a9ef05c32d089004e104364ce42324837 /samples/bpf/tracex6_user.c
downloadlinux-stable-4352b8aee98005853aa63f57d6377282de17a33f.tar.gz
linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.zip
Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted
Pull I3C updates from Alexandre Belloni: "A new driver this cycle, for the AMD AXI I3C controller. There are also new features such as IBI wakeup support, SETAASA device discovery and ACPI support for the the DAA methods, meaning we can now communicate with the SPD devices on DDR5 modules. New driver: - AMD AXI I3C master controller Subsystem: - I3C Common Command Code (CCC) handling improvements, especially around GET CCCs - SETAASA device discovery support - ACPI support for all existing DAA methods like SETDASA, SETNEWDA as well as I2C devices on I3C bus - IBI-based wakeup support Drivers: - dw: SETAASA support - mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C controller support, PIO queue management support for HCI v1.2 - renesas: improve suspend to RAM support, add runtime PM support" * tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits) i3c: dw: reduce do_daa time if there's no client i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2 i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode i3c: dw: rename "pclk" to "apb" to match dt-binding i3c: dw: make struct dw_i3c_cmd smaller i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding i3c: renesas: Don't register devices when ENTDAA times out i3c: master: dw-i3c-master: fix OD timing for first broadcast i3c: mipi-i3c-hci: Advertise IBI wakeup capability i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev() i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI i3c: master: Reject IBI requests from non-IBI-capable devices i3c: master: Add helper to query bus wakeup requirements i3c: master: Report wakeup events for IBIs i3c: master: Support IBI-based wakeup capability i3c: master: Fix potential UAF in i3c_device_match() i3c: master: Fix potential UAF in i3c_device_uevent() i3c: Make dev->desc locking assumptions explicit i3c: master: Fix use-after-free of master->this ...
Diffstat (limited to 'samples/bpf/tracex6_user.c')
-rw-r--r--samples/bpf/tracex6_user.c222
1 files changed, 222 insertions, 0 deletions
diff --git a/samples/bpf/tracex6_user.c b/samples/bpf/tracex6_user.c
new file mode 100644
index 000000000..ae811ac83
--- /dev/null
+++ b/samples/bpf/tracex6_user.c
@@ -0,0 +1,222 @@
+// SPDX-License-Identifier: GPL-2.0
+#define _GNU_SOURCE
+
+#include <assert.h>
+#include <fcntl.h>
+#include <linux/perf_event.h>
+#include <sched.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/ioctl.h>
+#include <sys/time.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <unistd.h>
+
+#include <bpf/bpf.h>
+#include <bpf/libbpf.h>
+#include "perf-sys.h"
+
+#define SAMPLE_PERIOD 0x7fffffffffffffffULL
+
+/* counters, values, values2 */
+static int map_fd[3];
+
+static void check_on_cpu(int cpu, struct perf_event_attr *attr)
+{
+ struct bpf_perf_event_value value2;
+ int pmu_fd, error = 0;
+ cpu_set_t set;
+ __u64 value;
+
+ /* Move to target CPU */
+ CPU_ZERO(&set);
+ CPU_SET(cpu, &set);
+ assert(sched_setaffinity(0, sizeof(set), &set) == 0);
+ /* Open perf event and attach to the perf_event_array */
+ pmu_fd = sys_perf_event_open(attr, -1/*pid*/, cpu/*cpu*/, -1/*group_fd*/, 0);
+ if (pmu_fd < 0) {
+ fprintf(stderr, "sys_perf_event_open failed on CPU %d\n", cpu);
+ error = 1;
+ goto on_exit;
+ }
+ assert(bpf_map_update_elem(map_fd[0], &cpu, &pmu_fd, BPF_ANY) == 0);
+ assert(ioctl(pmu_fd, PERF_EVENT_IOC_ENABLE, 0) == 0);
+ /* Trigger the kprobe */
+ bpf_map_get_next_key(map_fd[1], &cpu, NULL);
+ /* Check the value */
+ if (bpf_map_lookup_elem(map_fd[1], &cpu, &value)) {
+ fprintf(stderr, "Value missing for CPU %d\n", cpu);
+ error = 1;
+ goto on_exit;
+ } else {
+ fprintf(stderr, "CPU %d: %llu\n", cpu, value);
+ }
+ /* The above bpf_map_lookup_elem should trigger the second kprobe */
+ if (bpf_map_lookup_elem(map_fd[2], &cpu, &value2)) {
+ fprintf(stderr, "Value2 missing for CPU %d\n", cpu);
+ error = 1;
+ goto on_exit;
+ } else {
+ fprintf(stderr, "CPU %d: counter: %llu, enabled: %llu, running: %llu\n", cpu,
+ value2.counter, value2.enabled, value2.running);
+ }
+
+on_exit:
+ assert(bpf_map_delete_elem(map_fd[0], &cpu) == 0 || error);
+ assert(ioctl(pmu_fd, PERF_EVENT_IOC_DISABLE, 0) == 0 || error);
+ assert(close(pmu_fd) == 0 || error);
+ assert(bpf_map_delete_elem(map_fd[1], &cpu) == 0 || error);
+ exit(error);
+}
+
+static void test_perf_event_array(struct perf_event_attr *attr,
+ const char *name)
+{
+ int i, status, nr_cpus = sysconf(_SC_NPROCESSORS_CONF);
+ pid_t pid[nr_cpus];
+ int err = 0;
+
+ printf("Test reading %s counters\n", name);
+
+ for (i = 0; i < nr_cpus; i++) {
+ pid[i] = fork();
+ assert(pid[i] >= 0);
+ if (pid[i] == 0) {
+ check_on_cpu(i, attr);
+ exit(1);
+ }
+ }
+
+ for (i = 0; i < nr_cpus; i++) {
+ assert(waitpid(pid[i], &status, 0) == pid[i]);
+ err |= status;
+ }
+
+ if (err)
+ printf("Test: %s FAILED\n", name);
+}
+
+static void test_bpf_perf_event(void)
+{
+ struct perf_event_attr attr_cycles = {
+ .freq = 0,
+ .sample_period = SAMPLE_PERIOD,
+ .inherit = 0,
+ .type = PERF_TYPE_HARDWARE,
+ .read_format = 0,
+ .sample_type = 0,
+ .config = PERF_COUNT_HW_CPU_CYCLES,
+ };
+ struct perf_event_attr attr_clock = {
+ .freq = 0,
+ .sample_period = SAMPLE_PERIOD,
+ .inherit = 0,
+ .type = PERF_TYPE_SOFTWARE,
+ .read_format = 0,
+ .sample_type = 0,
+ .config = PERF_COUNT_SW_CPU_CLOCK,
+ };
+ struct perf_event_attr attr_raw = {
+ .freq = 0,
+ .sample_period = SAMPLE_PERIOD,
+ .inherit = 0,
+ .type = PERF_TYPE_RAW,
+ .read_format = 0,
+ .sample_type = 0,
+ /* Intel Instruction Retired */
+ .config = 0xc0,
+ };
+ struct perf_event_attr attr_l1d_load = {
+ .freq = 0,
+ .sample_period = SAMPLE_PERIOD,
+ .inherit = 0,
+ .type = PERF_TYPE_HW_CACHE,
+ .read_format = 0,
+ .sample_type = 0,
+ .config =
+ PERF_COUNT_HW_CACHE_L1D |
+ (PERF_COUNT_HW_CACHE_OP_READ << 8) |
+ (PERF_COUNT_HW_CACHE_RESULT_ACCESS << 16),
+ };
+ struct perf_event_attr attr_llc_miss = {
+ .freq = 0,
+ .sample_period = SAMPLE_PERIOD,
+ .inherit = 0,
+ .type = PERF_TYPE_HW_CACHE,
+ .read_format = 0,
+ .sample_type = 0,
+ .config =
+ PERF_COUNT_HW_CACHE_LL |
+ (PERF_COUNT_HW_CACHE_OP_READ << 8) |
+ (PERF_COUNT_HW_CACHE_RESULT_MISS << 16),
+ };
+ struct perf_event_attr attr_msr_tsc = {
+ .freq = 0,
+ .sample_period = 0,
+ .inherit = 0,
+ /* From /sys/bus/event_source/devices/msr/ */
+ .type = 7,
+ .read_format = 0,
+ .sample_type = 0,
+ .config = 0,
+ };
+
+ test_perf_event_array(&attr_cycles, "HARDWARE-cycles");
+ test_perf_event_array(&attr_clock, "SOFTWARE-clock");
+ test_perf_event_array(&attr_raw, "RAW-instruction-retired");
+ test_perf_event_array(&attr_l1d_load, "HW_CACHE-L1D-load");
+
+ /* below tests may fail in qemu */
+ test_perf_event_array(&attr_llc_miss, "HW_CACHE-LLC-miss");
+ test_perf_event_array(&attr_msr_tsc, "Dynamic-msr-tsc");
+}
+
+int main(int argc, char **argv)
+{
+ struct bpf_link *links[2];
+ struct bpf_program *prog;
+ struct bpf_object *obj;
+ char filename[256];
+ int i = 0;
+
+ snprintf(filename, sizeof(filename), "%s.bpf.o", argv[0]);
+ obj = bpf_object__open_file(filename, NULL);
+ if (libbpf_get_error(obj)) {
+ fprintf(stderr, "ERROR: opening BPF object file failed\n");
+ return 0;
+ }
+
+ /* load BPF program */
+ if (bpf_object__load(obj)) {
+ fprintf(stderr, "ERROR: loading BPF object file failed\n");
+ goto cleanup;
+ }
+
+ map_fd[0] = bpf_object__find_map_fd_by_name(obj, "counters");
+ map_fd[1] = bpf_object__find_map_fd_by_name(obj, "values");
+ map_fd[2] = bpf_object__find_map_fd_by_name(obj, "values2");
+ if (map_fd[0] < 0 || map_fd[1] < 0 || map_fd[2] < 0) {
+ fprintf(stderr, "ERROR: finding a map in obj file failed\n");
+ goto cleanup;
+ }
+
+ bpf_object__for_each_program(prog, obj) {
+ links[i] = bpf_program__attach(prog);
+ if (libbpf_get_error(links[i])) {
+ fprintf(stderr, "ERROR: bpf_program__attach failed\n");
+ links[i] = NULL;
+ goto cleanup;
+ }
+ i++;
+ }
+
+ test_bpf_perf_event();
+
+cleanup:
+ for (i--; i >= 0; i--)
+ bpf_link__destroy(links[i]);
+
+ bpf_object__close(obj);
+ return 0;
+}