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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-23 13:28:57 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-23 13:28:57 -0700 |
| commit | 4352b8aee98005853aa63f57d6377282de17a33f (patch) | |
| tree | 27614d7a9ef05c32d089004e104364ce42324837 /samples/bpf/sampleip_user.c | |
| download | linux-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/sampleip_user.c')
| -rw-r--r-- | samples/bpf/sampleip_user.c | 234 |
1 files changed, 234 insertions, 0 deletions
diff --git a/samples/bpf/sampleip_user.c b/samples/bpf/sampleip_user.c new file mode 100644 index 000000000..9283f4784 --- /dev/null +++ b/samples/bpf/sampleip_user.c @@ -0,0 +1,234 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * sampleip: sample instruction pointer and frequency count in a BPF map. + * + * Copyright 2016 Netflix, Inc. + */ +#include <stdio.h> +#include <stdlib.h> +#include <unistd.h> +#include <errno.h> +#include <signal.h> +#include <string.h> +#include <linux/perf_event.h> +#include <linux/ptrace.h> +#include <linux/bpf.h> +#include <bpf/bpf.h> +#include <bpf/libbpf.h> +#include "perf-sys.h" +#include "trace_helpers.h" + +#define DEFAULT_FREQ 99 +#define DEFAULT_SECS 5 +#define MAX_IPS 8192 + +static int map_fd; +static int nr_cpus; +static long _text_addr; + +static void usage(void) +{ + printf("USAGE: sampleip [-F freq] [duration]\n"); + printf(" -F freq # sample frequency (Hertz), default 99\n"); + printf(" duration # sampling duration (seconds), default 5\n"); +} + +static int sampling_start(int freq, struct bpf_program *prog, + struct bpf_link *links[]) +{ + int i, pmu_fd; + + struct perf_event_attr pe_sample_attr = { + .type = PERF_TYPE_SOFTWARE, + .freq = 1, + .sample_period = freq, + .config = PERF_COUNT_SW_CPU_CLOCK, + .inherit = 1, + }; + + for (i = 0; i < nr_cpus; i++) { + pmu_fd = sys_perf_event_open(&pe_sample_attr, -1 /* pid */, i, + -1 /* group_fd */, 0 /* flags */); + if (pmu_fd < 0) { + fprintf(stderr, "ERROR: Initializing perf sampling\n"); + return 1; + } + links[i] = bpf_program__attach_perf_event(prog, pmu_fd); + if (libbpf_get_error(links[i])) { + fprintf(stderr, "ERROR: Attach perf event\n"); + links[i] = NULL; + close(pmu_fd); + return 1; + } + } + + return 0; +} + +static void sampling_end(struct bpf_link *links[]) +{ + int i; + + for (i = 0; i < nr_cpus; i++) + bpf_link__destroy(links[i]); +} + +struct ipcount { + __u64 ip; + __u32 count; +}; + +/* used for sorting */ +struct ipcount counts[MAX_IPS]; + +static int count_cmp(const void *p1, const void *p2) +{ + return ((struct ipcount *)p1)->count - ((struct ipcount *)p2)->count; +} + +static void print_ip_map(int fd) +{ + struct ksym *sym; + __u64 key, next_key; + __u32 value; + int i, max; + + printf("%-19s %-32s %s\n", "ADDR", "KSYM", "COUNT"); + + /* fetch IPs and counts */ + key = 0, i = 0; + while (bpf_map_get_next_key(fd, &key, &next_key) == 0) { + bpf_map_lookup_elem(fd, &next_key, &value); + counts[i].ip = next_key; + counts[i++].count = value; + key = next_key; + } + max = i; + + /* sort and print */ + qsort(counts, max, sizeof(struct ipcount), count_cmp); + for (i = 0; i < max; i++) { + if (counts[i].ip > _text_addr) { + sym = ksym_search(counts[i].ip); + if (!sym) { + printf("ksym not found. Is kallsyms loaded?\n"); + continue; + } + + printf("0x%-17llx %-32s %u\n", counts[i].ip, sym->name, + counts[i].count); + } else { + printf("0x%-17llx %-32s %u\n", counts[i].ip, "(user)", + counts[i].count); + } + } + + if (max == MAX_IPS) { + printf("WARNING: IP hash was full (max %d entries); ", max); + printf("may have dropped samples\n"); + } +} + +static void int_exit(int sig) +{ + printf("\n"); + print_ip_map(map_fd); + exit(0); +} + +int main(int argc, char **argv) +{ + int opt, freq = DEFAULT_FREQ, secs = DEFAULT_SECS, error = 1; + struct bpf_object *obj = NULL; + struct bpf_program *prog; + struct bpf_link **links; + char filename[256]; + + /* process arguments */ + while ((opt = getopt(argc, argv, "F:h")) != -1) { + switch (opt) { + case 'F': + freq = atoi(optarg); + break; + case 'h': + default: + usage(); + return 0; + } + } + if (argc - optind == 1) + secs = atoi(argv[optind]); + if (freq == 0 || secs == 0) { + usage(); + return 1; + } + + /* initialize kernel symbol translation */ + if (load_kallsyms()) { + fprintf(stderr, "ERROR: loading /proc/kallsyms\n"); + return 2; + } + + /* used to determine whether the address is kernel space */ + _text_addr = ksym_get_addr("_text"); + if (!_text_addr) { + fprintf(stderr, "ERROR: no '_text' in /proc/kallsyms\n"); + return 3; + } + + /* create perf FDs for each CPU */ + nr_cpus = sysconf(_SC_NPROCESSORS_ONLN); + links = calloc(nr_cpus, sizeof(struct bpf_link *)); + if (!links) { + fprintf(stderr, "ERROR: malloc of links\n"); + goto cleanup; + } + + snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]); + obj = bpf_object__open_file(filename, NULL); + if (libbpf_get_error(obj)) { + fprintf(stderr, "ERROR: opening BPF object file failed\n"); + obj = NULL; + goto cleanup; + } + + prog = bpf_object__find_program_by_name(obj, "do_sample"); + if (!prog) { + fprintf(stderr, "ERROR: finding a prog in obj file failed\n"); + goto cleanup; + } + + /* load BPF program */ + if (bpf_object__load(obj)) { + fprintf(stderr, "ERROR: loading BPF object file failed\n"); + goto cleanup; + } + + map_fd = bpf_object__find_map_fd_by_name(obj, "ip_map"); + if (map_fd < 0) { + fprintf(stderr, "ERROR: finding a map in obj file failed\n"); + goto cleanup; + } + + signal(SIGINT, int_exit); + signal(SIGTERM, int_exit); + + /* do sampling */ + printf("Sampling at %d Hertz for %d seconds. Ctrl-C also ends.\n", + freq, secs); + if (sampling_start(freq, prog, links) != 0) + goto cleanup; + + sleep(secs); + error = 0; + +cleanup: + sampling_end(links); + /* output sample counts */ + if (!error) + print_ip_map(map_fd); + + free(links); + bpf_object__close(obj); + return error; +} |
