From 644e7329a6461a6a690c5a67c0cdac508802d4b3 Mon Sep 17 00:00:00 2001 From: jyf111 Date: Sat, 12 Aug 2023 23:01:35 +0800 Subject: [PATCH] [buf] fix multi-thread stack depth problem --- .../User_Function_Tracer/README.md | 1 - .../User_Function_Tracer/src/utrace.bpf.c | 82 +++++++++++++------ .../User_Function_Tracer/src/utrace.c | 50 ++++++----- .../User_Function_Tracer/src/utrace.h | 11 ++- 4 files changed, 86 insertions(+), 58 deletions(-) diff --git a/eBPF_Supermarket/User_Function_Tracer/README.md b/eBPF_Supermarket/User_Function_Tracer/README.md index 2752194a3..aa095c62c 100644 --- a/eBPF_Supermarket/User_Function_Tracer/README.md +++ b/eBPF_Supermarket/User_Function_Tracer/README.md @@ -38,4 +38,3 @@ Examples: ### TODO - simplify c++ symbols - more tests -- multithread diff --git a/eBPF_Supermarket/User_Function_Tracer/src/utrace.bpf.c b/eBPF_Supermarket/User_Function_Tracer/src/utrace.bpf.c index 228511fdd..6a5c8ef7a 100644 --- a/eBPF_Supermarket/User_Function_Tracer/src/utrace.bpf.c +++ b/eBPF_Supermarket/User_Function_Tracer/src/utrace.bpf.c @@ -26,68 +26,96 @@ char LICENSE[] SEC("license") = "Dual BSD/GPL"; +static int global_sz; +static int current_pid; struct { __uint(type, BPF_MAP_TYPE_HASH); - __uint(max_entries, 8192); - __type(key, s32); - __type(value, u64); + __type(key, __u32); + __type(value, __u64); + __uint(max_entries, MAX_STACK_DEPTH); } function_start SEC(".maps"); +struct { + __uint(type, BPF_MAP_TYPE_HASH); + __type(key, __u32); + __type(value, __u32); + __uint(max_entries, MAX_THREAD_NUM); +} stack_depth SEC(".maps"); + struct { __uint(type, BPF_MAP_TYPE_RINGBUF); - __uint(max_entries, 8192 * 1024); + __uint(max_entries, 2048 * 4096); } records SEC(".maps"); SEC("uprobe/trace") int BPF_KPROBE(uprobe) { struct profile_record *r; - pid_t pid, tid, cpu_id; - u64 id, ts; + pid_t tid, cpu_id; + __u64 ts; + __u32 *depth_ptr; + __u32 depth; - id = bpf_get_current_pid_tgid(); - tid = (u32)id; - pid = id >> 32; + current_pid = tid = (__u32)bpf_get_current_pid_tgid(); cpu_id = bpf_get_smp_processor_id(); r = bpf_ringbuf_reserve(&records, sizeof(*r), 0); if (!r) return 0; + r->tid = tid; r->cpu_id = cpu_id; + r->timestamp = 0; r->duration_ns = 0; - r->ustack_sz = - bpf_get_stack(ctx, r->ustack, sizeof(r->ustack), BPF_F_USER_STACK) / sizeof(r->ustack[0]); + bpf_get_stack(ctx, &r->ustack, sizeof(r->ustack), BPF_F_USER_STACK); + depth_ptr = bpf_map_lookup_elem(&stack_depth, &tid); + if (depth_ptr) + r->ustack_sz = depth = *depth_ptr + 1; + else + r->ustack_sz = depth = 0; + r->global_sz = global_sz; r->exit = 0; - s32 ustack_sz = r->ustack_sz; - ts = bpf_ktime_get_ns(); - bpf_map_update_elem(&function_start, &ustack_sz, &ts, BPF_ANY); + bpf_ringbuf_submit(r, 0); + + ts = bpf_ktime_get_ns(); + bpf_map_update_elem(&function_start, &global_sz, &ts, BPF_NOEXIST); + ++global_sz; + bpf_map_update_elem(&stack_depth, &tid, &depth, BPF_ANY); return 0; } SEC("uretprobe/trace") int BPF_KRETPROBE(uretprobe) { struct profile_record *r; - pid_t pid, tid, cpu_id; - u64 id, end_ts = bpf_ktime_get_ns(); - u64 *start_ts; - s32 ustack_sz; + pid_t tid, cpu_id; + __u64 *start_ts_ptr; + __u64 end_ts = bpf_ktime_get_ns(); + __u32 *depth_ptr; - id = bpf_get_current_pid_tgid(); + current_pid = tid = (__u32)bpf_get_current_pid_tgid(); cpu_id = bpf_get_smp_processor_id(); - pid = id >> 32; - tid = (u32)id; + + depth_ptr = bpf_map_lookup_elem(&stack_depth, &tid); + if (!depth_ptr) return 0; r = bpf_ringbuf_reserve(&records, sizeof(*r), 0); if (!r) return 0; + + --global_sz; + r->tid = tid; r->cpu_id = cpu_id; - r->ustack_sz = bpf_get_stack(ctx, r->ustack, sizeof(r->ustack), BPF_F_USER_STACK) / - sizeof(sizeof(r->ustack[0])); - ustack_sz = r->ustack_sz; - start_ts = bpf_map_lookup_elem(&function_start, &ustack_sz); - if (start_ts) r->duration_ns = end_ts - *start_ts; - bpf_map_delete_elem(&function_start, &ustack_sz); + r->timestamp = 0; + start_ts_ptr = bpf_map_lookup_elem(&function_start, &global_sz); + if (start_ts_ptr) r->duration_ns = end_ts - *start_ts_ptr; + bpf_get_stack(ctx, &r->ustack, sizeof(r->ustack), BPF_F_USER_STACK); + r->ustack_sz = *depth_ptr; + r->global_sz = global_sz; r->exit = 1; + bpf_ringbuf_submit(r, 0); + + bpf_map_delete_elem(&function_start, &global_sz); + --*depth_ptr; + bpf_map_update_elem(&stack_depth, &tid, depth_ptr, BPF_ANY); return 0; } \ No newline at end of file diff --git a/eBPF_Supermarket/User_Function_Tracer/src/utrace.c b/eBPF_Supermarket/User_Function_Tracer/src/utrace.c index f6ec83e7e..f614dc776 100644 --- a/eBPF_Supermarket/User_Function_Tracer/src/utrace.c +++ b/eBPF_Supermarket/User_Function_Tracer/src/utrace.c @@ -170,6 +170,10 @@ bool symbolize(size_t addr) { } static int handle_event(void *ctx, void *data, size_t data_sz) { + static struct profile_record pending_r; + static int pending = 0; + static int status = -1; /**< 0: exec 1: exit */ + const struct profile_record *r = data; if (r->exit) { @@ -177,58 +181,50 @@ static int handle_event(void *ctx, void *data, size_t data_sz) { // for (int i = 0; i < r->ustack_sz; i++) LOG(" %llx", r->ustack[i]); // LOG(" %s\n", stack_func[r->ustack_sz]); // return 0; - if (status == 0 && r->ustack_sz == pre_ustack_sz) { - log_cpuid(r->cpu_id); + if (status == 0) { + log_cpuid(pending_r.cpu_id); log_split(); - log_tid(r->tid); + log_tid(pending_r.tid); log_split(); log_time(r->duration_ns); log_split(); - log_char(' ', 2 * r->ustack_sz - 2); - LOG("%s();\n", stack_func[r->ustack_sz]); - status = 1; - pre_ustack_sz = r->ustack_sz; - } else if (status == 1 && r->ustack_sz == pre_ustack_sz - 1) { + log_char(' ', 2 * pending_r.ustack_sz); + LOG("%s();\n", stack_func[pending_r.global_sz]); + } else { // status == 1 log_cpuid(r->cpu_id); log_split(); log_tid(r->tid); log_split(); log_time(r->duration_ns); log_split(); - log_char(' ', 2 * r->ustack_sz - 2); - LOG("} "); - log_color(TERM_GRAY); - LOG("/* %s */", stack_func[r->ustack_sz]); - log_color(TERM_NC); - LOG("\n"); - status = 1; - pre_ustack_sz = r->ustack_sz; + log_char(' ', 2 * r->ustack_sz); + LOG("} " TERM_GRAY "/* %s */" TERM_NC "\n", stack_func[r->global_sz]); } + pending = 0; + status = 1; } else { // LOG("EXEC"); // for (int i = 0; i < r->ustack_sz; i++) LOG(" %llx", r->ustack[i]); // if (symbolize(r->ustack[0])) { - // memcpy(stack_func[r->ustack_sz], buf, sizeof(buf)); + // memcpy(stack_func[r->ustack_sz], buf, sizeof(buf)); // } // LOG(" %s\n", stack_func[r->ustack_sz]); // return 0; - if (status == -1 && r->ustack_sz != 1) return 0; - if (status == 0 && r->ustack_sz != pre_ustack_sz + 1) return 0; - if (status == 1 && r->ustack_sz != pre_ustack_sz) return 0; if (status == 0) { - log_cpuid(r->cpu_id); + log_cpuid(pending_r.cpu_id); log_split(); - log_tid(r->tid); + log_tid(pending_r.tid); log_split(); log_char(' ', 11); log_split(); - log_char(' ', 2 * r->ustack_sz - 4); - LOG("%s() {\n", stack_func[r->ustack_sz - 1]); + log_char(' ', 2 * pending_r.ustack_sz); + LOG("%s() {\n", stack_func[pending_r.global_sz]); } - if (symbolize(r->ustack[0])) { - memcpy(stack_func[r->ustack_sz], buf, sizeof(buf)); + if (symbolize(r->ustack)) { + memcpy(stack_func[r->global_sz], buf, sizeof(buf)); + pending_r = *r; + pending = 1; status = 0; - pre_ustack_sz = r->ustack_sz; } } return 0; diff --git a/eBPF_Supermarket/User_Function_Tracer/src/utrace.h b/eBPF_Supermarket/User_Function_Tracer/src/utrace.h index 2401407c6..77fce87d1 100644 --- a/eBPF_Supermarket/User_Function_Tracer/src/utrace.h +++ b/eBPF_Supermarket/User_Function_Tracer/src/utrace.h @@ -19,20 +19,23 @@ #ifndef UTRACE_UTRACE_H #define UTRACE_UTRACE_H +#define MAX_THREAD_NUM 32 #define MAX_STACK_DEPTH 128 #define MAX_MANGLED_LEN 128 #define MAX_SYMBOL_LEN 1024 #define MAX_PATH_LEN 256 -typedef unsigned long long stack_trace_t[MAX_STACK_DEPTH]; +typedef unsigned long long stack_trace_t; /** * @brief 内核态传给用户态的数据 */ struct profile_record { - unsigned int tid; /**< 线程编号 */ - unsigned int cpu_id; /**< CPU编号 */ + unsigned int tid; /**< 线程编号 */ + unsigned int next_tid; /**< 切换后的线程编号 */ + unsigned int cpu_id; /**< CPU编号 */ + unsigned long long timestamp; /**< 时间戳 */ unsigned long long duration_ns; /**< 函数时延 */ unsigned int kstack_sz; /**< 内核栈大小 */ @@ -41,6 +44,8 @@ struct profile_record { unsigned int ustack_sz; /**< 用户栈大小 */ stack_trace_t ustack; /**< 用户栈 */ + unsigned int global_sz; /**< 当前函数深度（考虑了多线程） */ + int exit; /**< 是否为函数退出时 */ };