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31-goroutine/goroutine.bpf.c

@@ -28,8 +28,6 @@
 #include <bpf/bpf_helpers.h>
 #include <bpf/bpf_tracing.h>
 
-
-
 #define GOID_OFFSET 0x98
 
 struct {
@@ -40,7 +38,7 @@ struct {
 SEC("uprobe/./go-server-http/main:runtime.casgstatus")
 int uprobe_runtime_casgstatus(struct pt_regs *ctx) {
   int newval = ctx->cx;
-  void *gp = ctx->ax;
+  void *gp = (void*)ctx->ax;
   struct goroutine_execute_data *data;
   u64 goid;
   if (bpf_probe_read_user(&goid, sizeof(goid), gp + GOID_OFFSET) == 0) {

31-goroutine/goroutine.c

@@ -1,172 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-#include <argp.h>
-#include <signal.h>
-#include <stdio.h>
-#include <time.h>
-#include <sys/resource.h>
-#include <bpf/libbpf.h>
-#include "goroutine.h"
-#include "goroutine.skel.h"
-
-static struct env {
-	bool verbose;
-	long min_duration_ms;
-} env;
-
-const char *argp_program_version = "goroutine 0.0";
-const char *argp_program_bug_address = "<bpf@vger.kernel.org>";
-const char argp_program_doc[] =
-"BPF goroutine demo application.\n"
-"\n"
-"It traces process start and exits and shows associated \n"
-"information (filename, process duration, PID and PPID, etc).\n"
-"\n"
-"USAGE: ./goroutine [-d <min-duration-ms>] [-v]\n";
-
-static const struct argp_option opts[] = {
-	{ "verbose", 'v', NULL, 0, "Verbose debug output" },
-	{ "duration", 'd', "DURATION-MS", 0, "Minimum process duration (ms) to report" },
-	{},
-};
-
-static error_t parse_arg(int key, char *arg, struct argp_state *state)
-{
-	switch (key) {
-	case 'v':
-		env.verbose = true;
-		break;
-	case 'd':
-		errno = 0;
-		env.min_duration_ms = strtol(arg, NULL, 10);
-		if (errno || env.min_duration_ms <= 0) {
-			fprintf(stderr, "Invalid duration: %s\n", arg);
-			argp_usage(state);
-		}
-		break;
-	case ARGP_KEY_ARG:
-		argp_usage(state);
-		break;
-	default:
-		return ARGP_ERR_UNKNOWN;
-	}
-	return 0;
-}
-
-static const struct argp argp = {
-	.options = opts,
-	.parser = parse_arg,
-	.doc = argp_program_doc,
-};
-
-static int libbpf_print_fn(enum libbpf_print_level level, const char *format, va_list args)
-{
-	if (level == LIBBPF_DEBUG && !env.verbose)
-		return 0;
-	return vfprintf(stderr, format, args);
-}
-
-static volatile bool exiting = false;
-
-static void sig_handler(int sig)
-{
-	exiting = true;
-}
-
-static int handle_event(void *ctx, void *data, size_t data_sz)
-{
-	const struct event *e = data;
-	struct tm *tm;
-	char ts[32];
-	time_t t;
-
-	time(&t);
-	tm = localtime(&t);
-	strftime(ts, sizeof(ts), "%H:%M:%S", tm);
-
-	if (e->exit_event) {
-		printf("%-8s %-5s %-16s %-7d %-7d [%u]",
-		       ts, "EXIT", e->comm, e->pid, e->ppid, e->exit_code);
-		if (e->duration_ns)
-			printf(" (%llums)", e->duration_ns / 1000000);
-		printf("\n");
-	} else {
-		printf("%-8s %-5s %-16s %-7d %-7d %s\n",
-		       ts, "EXEC", e->comm, e->pid, e->ppid, e->filename);
-	}
-
-	return 0;
-}
-
-int main(int argc, char **argv)
-{
-	struct ring_buffer *rb = NULL;
-	struct goroutine_bpf *skel;
-	int err;
-
-	/* Parse command line arguments */
-	err = argp_parse(&argp, argc, argv, 0, NULL, NULL);
-	if (err)
-		return err;
-
-	/* Set up libbpf errors and debug info callback */
-	libbpf_set_print(libbpf_print_fn);
-
-	/* Cleaner handling of Ctrl-C */
-	signal(SIGINT, sig_handler);
-	signal(SIGTERM, sig_handler);
-
-	/* Load and verify BPF application */
-	skel = goroutine_bpf__open();
-	if (!skel) {
-		fprintf(stderr, "Failed to open and load BPF skeleton\n");
-		return 1;
-	}
-
-	/* Parameterize BPF code with minimum duration parameter */
-	skel->rodata->min_duration_ns = env.min_duration_ms * 1000000ULL;
-
-	/* Load & verify BPF programs */
-	err = goroutine_bpf__load(skel);
-	if (err) {
-		fprintf(stderr, "Failed to load and verify BPF skeleton\n");
-		goto cleanup;
-	}
-
-	/* Attach tracepoints */
-	err = goroutine_bpf__attach(skel);
-	if (err) {
-		fprintf(stderr, "Failed to attach BPF skeleton\n");
-		goto cleanup;
-	}
-
-	/* Set up ring buffer polling */
-	rb = ring_buffer__new(bpf_map__fd(skel->maps.rb), handle_event, NULL, NULL);
-	if (!rb) {
-		err = -1;
-		fprintf(stderr, "Failed to create ring buffer\n");
-		goto cleanup;
-	}
-
-	/* Process events */
-	printf("%-8s %-5s %-16s %-7s %-7s %s\n",
-	       "TIME", "EVENT", "COMM", "PID", "PPID", "FILENAME/EXIT CODE");
-	while (!exiting) {
-		err = ring_buffer__poll(rb, 100 /* timeout, ms */);
-		/* Ctrl-C will cause -EINTR */
-		if (err == -EINTR) {
-			err = 0;
-			break;
-		}
-		if (err < 0) {
-			printf("Error polling perf buffer: %d\n", err);
-			break;
-		}
-	}
-
-cleanup:
-	/* Clean up */
-	ring_buffer__free(rb);
-	goroutine_bpf__destroy(skel);
-
-	return err < 0 ? -err : 0;
-}

33-funclatency/Makefile

@@ -5,7 +5,7 @@ LIBBPF_SRC := $(abspath ../third_party/libbpf/src)
 BPFTOOL_SRC := $(abspath ../third_party/bpftool/src)
 LIBBPF_OBJ := $(abspath $(OUTPUT)/libbpf.a)
 BPFTOOL_OUTPUT ?= $(abspath $(OUTPUT)/bpftool)
-BPFTOOL ?= $(BPFTOOL_OUTPUT)/funclatency/bpftool
+BPFTOOL ?= $(BPFTOOL_OUTPUT)/bootstrap/bpftool
 LIBBLAZESYM_SRC := $(abspath ../third_party/blazesym/)
 LIBBLAZESYM_OBJ := $(abspath $(OUTPUT)/libblazesym.a)
 LIBBLAZESYM_HEADER := $(abspath $(OUTPUT)/blazesym.h)
@@ -24,13 +24,13 @@ INCLUDES := -I$(OUTPUT) -I../third_party/libbpf/include/uapi -I$(dir $(VMLINUX))
 CFLAGS := -g -Wall
 ALL_LDFLAGS := $(LDFLAGS) $(EXTRA_LDFLAGS)
 
-APPS = funclatency # minimal minimal_legacy uprobe kprobe fentry usdt sockfilter tc ksyscall
+APPS = funclatency
 
 CARGO ?= $(shell which cargo)
 ifeq ($(strip $(CARGO)),)
 BZS_APPS :=
 else
-BZS_APPS := # profile
+BZS_APPS := 
 APPS += $(BZS_APPS)
 # Required by libblazesym
 ALL_LDFLAGS += -lrt -ldl -lpthread -lm
@@ -91,7 +91,7 @@ $(LIBBPF_OBJ): $(wildcard $(LIBBPF_SRC)/*.[ch] $(LIBBPF_SRC)/Makefile) | $(OUTPU
 # Build bpftool
 $(BPFTOOL): | $(BPFTOOL_OUTPUT)
 	$(call msg,BPFTOOL,$@)
-	$(Q)$(MAKE) ARCH= CROSS_COMPILE= OUTPUT=$(BPFTOOL_OUTPUT)/ -C $(BPFTOOL_SRC) funclatency
+	$(Q)$(MAKE) ARCH= CROSS_COMPILE= OUTPUT=$(BPFTOOL_OUTPUT)/ -C $(BPFTOOL_SRC) bootstrap
 
 
 $(LIBBLAZESYM_SRC)/target/release/libblazesym.a::

33-funclatency/bits.bpf.h

@@ -0,0 +1,31 @@
+/* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */
+#ifndef __BITS_BPF_H
+#define __BITS_BPF_H
+
+#define READ_ONCE(x) (*(volatile typeof(x) *)&(x))
+#define WRITE_ONCE(x, val) ((*(volatile typeof(x) *)&(x)) = val)
+
+static __always_inline u64 log2(u32 v)
+{
+	u32 shift, r;
+
+	r = (v > 0xFFFF) << 4; v >>= r;
+	shift = (v > 0xFF) << 3; v >>= shift; r |= shift;
+	shift = (v > 0xF) << 2; v >>= shift; r |= shift;
+	shift = (v > 0x3) << 1; v >>= shift; r |= shift;
+	r |= (v >> 1);
+
+	return r;
+}
+
+static __always_inline u64 log2l(u64 v)
+{
+	u32 hi = v >> 32;
+
+	if (hi)
+		return log2(hi) + 32;
+	else
+		return log2(v);
+}
+
+#endif /* __BITS_BPF_H */

33-funclatency/funclatency.bpf.c

@@ -33,13 +33,6 @@ static void entry(void)
 	bpf_map_update_elem(&starts, &pid, &nsec, BPF_ANY);
 }
 
-SEC("fentry/dummy_fentry")
-int BPF_PROG(dummy_fentry)
-{
-	entry();
-	return 0;
-}
-
 SEC("kprobe/dummy_kprobe")
 int BPF_KPROBE(dummy_kprobe)
 {
@@ -76,13 +69,6 @@ static void exit(void)
 	__sync_fetch_and_add(&hist[slot], 1);
 }
 
-SEC("fexit/dummy_fexit")
-int BPF_PROG(dummy_fexit)
-{
-	exit();
-	return 0;
-}
-
 SEC("kretprobe/dummy_kretprobe")
 int BPF_KRETPROBE(dummy_kretprobe)
 {

33-funclatency/funclatency.c

@@ -22,8 +22,6 @@
 #include <bpf/bpf.h>
 #include "funclatency.h"
 #include "funclatency.skel.h"
-#include "trace_helpers.h"
-#include "uprobe_helpers.h"
 
 #define warn(...) fprintf(stderr, __VA_ARGS__)
 
@@ -63,7 +61,7 @@ static const char program_doc[] =
 	"  ./funclatency -m do_nanosleep     # time do_nanosleep(), in milliseconds\n"
 	"  ./funclatency -u vfs_read         # time vfs_read(), in microseconds\n"
 	"  ./funclatency -p 181 vfs_read     # time process 181 only\n"
-	"  ./funclatency -p 181 c:read       # time the read() C library function\n"
+	"  ./funclatency -p 181 /usr/lib/x86_64-linux-gnu/libc.so.6:read       # time the read() C library function\n"
 	"  ./funclatency -p 181 :foo         # time foo() from pid 181's userspace\n"
 	"  ./funclatency -i 2 -d 10 vfs_read # output every 2 seconds, for 10s\n"
 	"  ./funclatency -mTi 5 vfs_read     # output every 5 seconds, with timestamps\n";
@@ -223,8 +221,6 @@ static int attach_kprobes(struct funclatency_bpf *obj)
 static int attach_uprobes(struct funclatency_bpf *obj)
 {
 	char *binary, *function;
-	char bin_path[PATH_MAX];
-	off_t func_off;
 	int ret = -1;
 	long err;
 
@@ -234,6 +230,7 @@ static int attach_uprobes(struct funclatency_bpf *obj)
 		warn("strdup failed");
 		return -1;
 	}
+	printf("tracing %s...\n", binary);
 	function = strchr(binary, ':');
 	if (!function)
 	{
@@ -242,20 +239,15 @@ static int attach_uprobes(struct funclatency_bpf *obj)
 	}
 	*function = '\0';
 	function++;
+	printf("tracing func %s in %s...\n", function, binary);
 
-	if (resolve_binary_path(binary, env.pid, bin_path, sizeof(bin_path)))
-		goto out_binary;
-
-	func_off = get_elf_func_offset(bin_path, function);
-	if (func_off < 0)
-	{
-		warn("Could not find %s in %s\n", function, bin_path);
-		goto out_binary;
-	}
+	LIBBPF_OPTS(bpf_uprobe_opts, opts);
+	opts.func_name = function;
+	opts.retprobe = false;
 
 	obj->links.dummy_kprobe =
-		bpf_program__attach_uprobe(obj->progs.dummy_kprobe, false,
-								   env.pid ?: -1, bin_path, func_off);
+		bpf_program__attach_uprobe_opts(obj->progs.dummy_kprobe, 
+								   env.pid ?: -1, binary, 0, &opts);
 	if (!obj->links.dummy_kprobe)
 	{
 		err = -errno;
@@ -263,9 +255,11 @@ static int attach_uprobes(struct funclatency_bpf *obj)
 		goto out_binary;
 	}
 
+	opts.retprobe = true;
+
 	obj->links.dummy_kretprobe =
-		bpf_program__attach_uprobe(obj->progs.dummy_kretprobe, true,
-								   env.pid ?: -1, bin_path, func_off);
+		bpf_program__attach_uprobe_opts(obj->progs.dummy_kretprobe, 
+								   env.pid ?: -1, binary, 0, &opts);
 	if (!obj->links.dummy_kretprobe)
 	{
 		err = -errno;
@@ -290,6 +284,10 @@ static void sig_hand(int signr)
 
 static struct sigaction sigact = {.sa_handler = sig_hand};
 
+#ifndef min
+#define min(a,b) ((a) < (b) ? (a) : (b))
+#endif
+
 static void print_stars(unsigned int val, unsigned int val_max, int width)
 {
 	int num_stars, num_spaces, i;
@@ -362,9 +360,7 @@ int main(int argc, char **argv)
 	struct tm *tm;
 	char ts[32];
 	time_t t;
-	int idx, cg_map_fd;
 	int cgfd = -1;
-	bool used_fentry = false;
 
 	err = argp_parse(&argp, argc, argv, 0, NULL, &env);
 	if (err)
@@ -439,7 +435,6 @@ int main(int argc, char **argv)
 
 cleanup:
 	funclatency_bpf__destroy(obj);
-	cleanup_core_btf(&open_opts);
 	if (cgfd > 0)
 		close(cgfd);
 

39-nginx/trace.bt

@@ -0,0 +1,49 @@
+#!/usr/sbin/bpftrace
+
+// Monitor the start of HTTP request processing
+uprobe:/usr/sbin/nginx:ngx_http_process_request
+{
+    printf("HTTP request processing started (tid: %d)\n", tid);
+    @start[tid] = nsecs;
+}
+
+// Monitor when an HTTP request is finalized
+uretprobe:/usr/sbin/nginx:ngx_http_finalize_request
+/@start[tid]/
+{
+    $elapsed = nsecs - @start[tid];
+    printf("HTTP request processed in %d ns (tid: %d)\n", $elapsed, tid);
+    delete(@start[tid]);
+}
+
+// Monitor the start of sending a request to an upstream server
+uprobe:/usr/sbin/nginx:ngx_http_upstream_send_request
+{
+    printf("Upstream request sending started (tid: %d)\n", tid);
+    @upstream_start[tid] = nsecs;
+}
+
+// Monitor when the upstream request is sent
+uretprobe:/usr/sbin/nginx:ngx_http_upstream_send_request
+/@upstream_start[tid]/
+{
+    $elapsed = nsecs - @upstream_start[tid];
+    printf("Upstream request sent in %d ns (tid: %d)\n", $elapsed, tid);
+    delete(@upstream_start[tid]);
+}
+
+// Monitor the start of event processing
+uprobe:/usr/sbin/nginx:ngx_event_process_posted
+{
+    printf("Event processing started (tid: %d)\n", tid);
+    @event_start[tid] = nsecs;
+}
+
+// Monitor when event processing is completed
+uretprobe:/usr/sbin/nginx:ngx_event_process_posted
+/@event_start[tid]/
+{
+    $elapsed = nsecs - @event_start[tid];
+    printf("Event processed in %d ns (tid: %d)\n", $elapsed, tid);
+    delete(@event_start[tid]);
+}