libbpf-tools/stackcount: Add libbpf-based stackcount tool#5410
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ismhong wants to merge 1 commit intoiovisor:masterfrom
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libbpf-tools/stackcount: Add libbpf-based stackcount tool#5410ismhong wants to merge 1 commit intoiovisor:masterfrom
ismhong wants to merge 1 commit intoiovisor:masterfrom
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This commit introduces libbpf version of stackcount tool based on BCC Python based stackcount. The usage is the same with original one. Change-Id: I1b057cded14f5803ebba9840837d903df25257f9 Signed-off-by: Ism Hong <ism.hong@gmail.com>
ismhong
requested review from
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chenhengqi,
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Pull request overview
Adds a new stackcount tool under libbpf-tools/ implemented with libbpf CO-RE, intended to mirror the BCC stackcount CLI for counting events and aggregating user/kernel stack traces.
Changes:
- Introduce new userspace implementation (
stackcount.c) with argp CLI, probe attach logic, and stack printing. - Introduce new BPF program (
stackcount.bpf.c) and shared header (stackcount.h) for stack-id aggregation in a hash map. - Wire the new tool into
libbpf-tools/Makefileand.gitignore.
Reviewed changes
Copilot reviewed 5 out of 5 changed files in this pull request and generated 11 comments.
Show a summary per file
| File | Description |
|---|---|
| libbpf-tools/stackcount.c | New userspace CLI, attach logic (kprobe/tp/uprobe), and stack aggregation/printing. |
| libbpf-tools/stackcount.bpf.c | New BPF program to collect stack IDs and increment counts. |
| libbpf-tools/stackcount.h | Shared key struct/constants between userspace and BPF. |
| libbpf-tools/Makefile | Adds stackcount to the build list. |
| libbpf-tools/.gitignore | Ignores the built stackcount binary. |
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| static __u64 *stack; | ||
| size_t i; | ||
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| stack = calloc(env.perf_max_stack_depth, sizeof(__u64)); |
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| { "timestamp", 'T', NULL, 0, "Include timestamp on output", 0 }, | ||
| { "regexp", 'r', NULL, 0, "Use regular expressions. " | ||
| "Default is '*' wildcards only.", 0 }, | ||
| { "offset", 's', NULL, 0, "Show address offsets", 0 }, |
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| " ./stackcount -p 185 c:malloc # count stacks for malloc in PID 185" | ||
| " ./stackcount t:sched:sched_fork # count stacks for sched_fork tracepoint" | ||
| " ./stackcount -p 185 u:node:* # count stacks for all USDT probes in node" |
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| cgroup_fd = open(env.cgroup_path, O_RDONLY); | ||
| if (cgroup_fd < 0) { | ||
| warn("failed to open cgroup path: %s\n", env.cgroup_path); | ||
| goto cleanup; | ||
| } | ||
| bpf_program__attach_cgroup(skel->progs.kprobe_prog, cgroup_fd); | ||
| bpf_program__attach_cgroup(skel->progs.tp_prog, cgroup_fd); | ||
| bpf_program__attach_cgroup(skel->progs.uprobe_prog, cgroup_fd); |
| for (i = 0; i < items_size; i++) { | ||
| if (env.folded) { | ||
| // print folded stack output | ||
| printf("%s;", items[i].key.name); |
| const struct count_info *A = a; | ||
| const struct count_info *B = b; | ||
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| return A->value - B->value; |
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| lookup_key = NULL; | ||
| while (bpf_map_get_next_key(counts_fd, lookup_key, &next_key) == 0) { | ||
| bpf_map_delete_elem(counts_fd, &next_key); | ||
| lookup_key = &next_key; | ||
| } |
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| if (strcmp(probe_type, "t") == 0) { | ||
| char *category = strtok(NULL, ":"); | ||
| char *event = strtok(NULL, ":"); |
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| while (!exiting) { | ||
| sleep(env.interval); | ||
| if (env.duration-- == 0) | ||
| break; | ||
| print_stacks(skel, ksyms, usyms); |
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| const volatile int target_pid = 0; | ||
| const volatile int target_cpu = -1; | ||
| const volatile bool kernel_stacks_only = false; | ||
| const volatile bool user_stacks_only = false; | ||
| const volatile bool per_pid = false; | ||
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| struct { | ||
| __uint(type, BPF_MAP_TYPE_HASH); | ||
| __uint(max_entries, MAX_ENTRIES); | ||
| __type(key, struct key_t); | ||
| __type(value, u64); | ||
| } counts SEC(".maps"); | ||
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| struct { | ||
| __uint(type, BPF_MAP_TYPE_STACK_TRACE); | ||
| __type(key, u32); | ||
| } stack_traces SEC(".maps"); | ||
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This commit introduces libbpf version of stackcount tool based on BCC Python based stackcount. The usage is the same with original one.
Change-Id: I1b057cded14f5803ebba9840837d903df25257f9