From 28dbf861deacb0321604bf1c5e1ccc34dd215669 Mon Sep 17 00:00:00 2001 From: Yonghong Song Date: Sat, 28 Apr 2018 22:28:13 -0700 Subject: samples/bpf: move common-purpose trace functions to selftests There is no functionality change in this patch. The common-purpose trace functions, including perf_event polling and ksym lookup, are moved from trace_output_user.c and bpf_load.c to selftests/bpf/trace_helpers.c so that these function can be reused later in selftests. Acked-by: Alexei Starovoitov Signed-off-by: Yonghong Song Signed-off-by: Alexei Starovoitov --- samples/bpf/bpf_load.c | 63 -------------------------------------------------- 1 file changed, 63 deletions(-) (limited to 'samples/bpf/bpf_load.c') diff --git a/samples/bpf/bpf_load.c b/samples/bpf/bpf_load.c index feca497d6afd..a27ef3c42e4e 100644 --- a/samples/bpf/bpf_load.c +++ b/samples/bpf/bpf_load.c @@ -648,66 +648,3 @@ void read_trace_pipe(void) } } } - -#define MAX_SYMS 300000 -static struct ksym syms[MAX_SYMS]; -static int sym_cnt; - -static int ksym_cmp(const void *p1, const void *p2) -{ - return ((struct ksym *)p1)->addr - ((struct ksym *)p2)->addr; -} - -int load_kallsyms(void) -{ - FILE *f = fopen("/proc/kallsyms", "r"); - char func[256], buf[256]; - char symbol; - void *addr; - int i = 0; - - if (!f) - return -ENOENT; - - while (!feof(f)) { - if (!fgets(buf, sizeof(buf), f)) - break; - if (sscanf(buf, "%p %c %s", &addr, &symbol, func) != 3) - break; - if (!addr) - continue; - syms[i].addr = (long) addr; - syms[i].name = strdup(func); - i++; - } - sym_cnt = i; - qsort(syms, sym_cnt, sizeof(struct ksym), ksym_cmp); - return 0; -} - -struct ksym *ksym_search(long key) -{ - int start = 0, end = sym_cnt; - int result; - - while (start < end) { - size_t mid = start + (end - start) / 2; - - result = key - syms[mid].addr; - if (result < 0) - end = mid; - else if (result > 0) - start = mid + 1; - else - return &syms[mid]; - } - - if (start >= 1 && syms[start - 1].addr < key && - key < syms[start].addr) - /* valid ksym */ - return &syms[start - 1]; - - /* out of range. return _stext */ - return &syms[0]; -} - -- cgit v1.2.3-59-g8ed1b From 34745aed515c1d6040110ff82378056533518eb6 Mon Sep 17 00:00:00 2001 From: Yonghong Song Date: Sun, 29 Apr 2018 19:27:48 -0700 Subject: samples/bpf: fix kprobe attachment issue on x64 Commit d5a00528b58c ("syscalls/core, syscalls/x86: Rename struct pt_regs-based sys_*() to __x64_sys_*()") renamed a lot of syscall function sys_*() to __x64_sys_*(). This caused several kprobe based samples/bpf tests failing. This patch fixed the problem in bpf_load.c. For x86_64 architecture, function name __x64_sys_*() will be first used for kprobe event creation. If the creation is successful, it will be used. Otherwise, function name sys_*() will be used for kprobe event creation. Fixes: d5a00528b58c ("syscalls/core, syscalls/x86: Rename struct pt_regs-based sys_*() to __x64_sys_*()") Signed-off-by: Yonghong Song Signed-off-by: Alexei Starovoitov --- samples/bpf/bpf_load.c | 34 ++++++++++++++++++++++++++-------- 1 file changed, 26 insertions(+), 8 deletions(-) (limited to 'samples/bpf/bpf_load.c') diff --git a/samples/bpf/bpf_load.c b/samples/bpf/bpf_load.c index a27ef3c42e4e..da9bccfaf391 100644 --- a/samples/bpf/bpf_load.c +++ b/samples/bpf/bpf_load.c @@ -145,6 +145,9 @@ static int load_and_attach(const char *event, struct bpf_insn *prog, int size) } if (is_kprobe || is_kretprobe) { + bool need_normal_check = true; + const char *event_prefix = ""; + if (is_kprobe) event += 7; else @@ -158,18 +161,33 @@ static int load_and_attach(const char *event, struct bpf_insn *prog, int size) if (isdigit(*event)) return populate_prog_array(event, fd); - snprintf(buf, sizeof(buf), - "echo '%c:%s %s' >> /sys/kernel/debug/tracing/kprobe_events", - is_kprobe ? 'p' : 'r', event, event); - err = system(buf); - if (err < 0) { - printf("failed to create kprobe '%s' error '%s'\n", - event, strerror(errno)); - return -1; +#ifdef __x86_64__ + if (strncmp(event, "sys_", 4) == 0) { + snprintf(buf, sizeof(buf), + "echo '%c:__x64_%s __x64_%s' >> /sys/kernel/debug/tracing/kprobe_events", + is_kprobe ? 'p' : 'r', event, event); + err = system(buf); + if (err >= 0) { + need_normal_check = false; + event_prefix = "__x64_"; + } + } +#endif + if (need_normal_check) { + snprintf(buf, sizeof(buf), + "echo '%c:%s %s' >> /sys/kernel/debug/tracing/kprobe_events", + is_kprobe ? 'p' : 'r', event, event); + err = system(buf); + if (err < 0) { + printf("failed to create kprobe '%s' error '%s'\n", + event, strerror(errno)); + return -1; + } } strcpy(buf, DEBUGFS); strcat(buf, "events/kprobes/"); + strcat(buf, event_prefix); strcat(buf, event); strcat(buf, "/id"); } else if (is_tracepoint) { -- cgit v1.2.3-59-g8ed1b