From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pl1-f179.google.com (mail-pl1-f179.google.com [209.85.214.179]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 96BEF16087B; Wed, 31 Jul 2024 19:49:54 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.179 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722455396; cv=none; b=nV5J/T0bgKbE/tylPC4rvoivAHWg+LzUxdyKFMyeaBEElBbL3FuMiLU8QBWZU6ANb0iN0AVFQVib0lVbO1Og7KUAUKgSqu86psDWrVKBvv6swJrctJ9GS305q1JgxcMOpgNjwjb7om8POu+S1AmcUtlxsPkcO+XSrx0dtKw24d8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722455396; c=relaxed/simple; bh=1hDFEnDRacC+it14el02NAS09S05fxBP/iOZ2CrCr4U=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=iDYQpFfI3jt9n/fUfroEyQooG2ev8nUD6oBDrWBUaLZ5b62ts4llqKN9AH5DsJLFVeNe8MZ0anuekjvCXcZ2XMOC4UEqRLmYqHvCcOmAbsEIgitQFjg2Gh9FfthQC/LCxwlkCeT7OYf8Ywc+Ny4Et3bfxkkgsma+FgTLWzGBir4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=OJ0qewH9; arc=none smtp.client-ip=209.85.214.179 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="OJ0qewH9" Received: by mail-pl1-f179.google.com with SMTP id d9443c01a7336-1fc4fccdd78so44150615ad.2; Wed, 31 Jul 2024 12:49:54 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1722455394; x=1723060194; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=AjNeGwJc12dU9jdKLQoXBpdjOEy73PqC7kWN5ZA1lMc=; b=OJ0qewH9dGSUHlOelavmYw+hQSpDsRD2RJSXuWmT3R1NzBrEoEMyGsdhgyuTrlEC/J xjHmL3ijljhUEj8rwewGT5LQ6F8MjmFjDjp1tKiT1KWjAk0JXhYjpPONHYunDcD/l9wC JIvrmXfUOrNpsPBY3YiHXmpVobhTxJxj8C0mQNR6prGLy3hcLhNIXxH3DwkwpX5WO7tD toc7v3K5uZ9F5GAYXbQto2SxPuzoPdY4jBZlpRkMLaEDyjkA8Y04Qz9ZE/DwL0BnotVO FGmOTRx7SKVmkT5YzkLlKQ3ZaOR0V1D3JXS4S8iDCBKNn61ayxzMetRI7CqoBuVDMKO4 tD4w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1722455394; x=1723060194; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=AjNeGwJc12dU9jdKLQoXBpdjOEy73PqC7kWN5ZA1lMc=; b=AFO3pXcJNSYu3wNP0zETYBbnrtriuaudH93VKmS4u5P1Fyn22y9mhsz86g+1VUWrgV U9iWeuBGx9H836gjCf8FNw0ot4klurCPAPqVQPPCobxj0z13xxDjH5c+oMu6fBHym397 pi39wdcrFqPFLjze12yiyu1sYtdVKGBhY8+QTVZweBCeVATefvei7H/DK3p9/ejoYRz2 D8NUyNN0wkwPmBLGooBAjXV4STcnbTJO8OK0c0WZbl9slM1omj9GCPwG5CdE/FBFkPfz cdgu3+fociXbWCadOQnrHqhtQXkbW8B06uuEKRXPzGecrCkoDjcPJQy81Z2tLzBiGtDA qNrQ== X-Forwarded-Encrypted: i=1; AJvYcCUFSsBzfoYK2IrowL9rtIJ3KawIO7aUtgaxvjucvxIvsO2wQoINiwS5/vSW1mBpliLd1e3JXKs+hRoXduBsI99pXxUr+nfS6/tGoqNnvkNrJ0hLaZsluaSHnKQNahqbCXJRKyuL1wuayy0RS6kp6g== X-Gm-Message-State: AOJu0Yy2fW9NUP/9V5m/w3bF6ntI+C/4Zek70KQdu8hsIz4Yb74JVDey CxYfiTmtiZ0DKL953X0HjfgMyMVhhRvSC49vqigMLp1Rm5XD3yEo X-Google-Smtp-Source: AGHT+IEKbYtd1+eom6MgcIkN129ZfhJbh7ClrjZHNQt6/BiMO0Pb656JztLD51QSDW4h+cDQKyjUsQ== X-Received: by 2002:a17:902:d2ca:b0:1fb:7f82:515 with SMTP id d9443c01a7336-1ff4cea205emr5843115ad.15.1722455393628; Wed, 31 Jul 2024 12:49:53 -0700 (PDT) Received: from localhost.localdomain ([120.229.49.244]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-1fed7837e40sm124708615ad.0.2024.07.31.12.49.50 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 31 Jul 2024 12:49:53 -0700 (PDT) From: Howard Chu To: acme@kernel.org Cc: adrian.hunter@intel.com, irogers@google.com, jolsa@kernel.org, kan.liang@linux.intel.com, namhyung@kernel.org, linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v1 1/3] perf trace: Set up beauty_map, load it to BPF Date: Thu, 1 Aug 2024 03:49:37 +0800 Message-ID: <20240731194939.4760-2-howardchu95@gmail.com> X-Mailer: git-send-email 2.45.2 In-Reply-To: <20240731194939.4760-1-howardchu95@gmail.com> References: <20240731194939.4760-1-howardchu95@gmail.com> Precedence: bulk X-Mailing-List: linux-perf-users@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Set up beauty_map, load it to BPF, in such format: if argument No.3 is a struct of size 32 bytes (of syscall number 114) beauty_map[114][2] = 32; if argument No.3 is a string (of syscall number 114) beauty_map[114][2] = 1; if argument No.3 is a buffer, its size is indicated by argument No.4 (of syscall number 114) beauty_map[114][2] = -4; /* -1 ~ -6, we'll read this buffer size in BPF */ Add type_id member to syscall_arg_fmt because it is required by btf_dump. Add syscall_arg__scnprintf_buf() to pretty print augmented buffer. Use btf_dump API to pretty print augmented struct pointer. Add trace__init_pid_filter(), to set up pid_filter before running BPF program. This way, we don't accidentally collect augmented data from processes we don't care about. Signed-off-by: Howard Chu --- tools/perf/builtin-trace.c | 254 ++++++++++++++++++++++++++++++++++++- 1 file changed, 250 insertions(+), 4 deletions(-) diff --git a/tools/perf/builtin-trace.c b/tools/perf/builtin-trace.c index 8af93a2f0bcd..cf52fda453e0 100644 --- a/tools/perf/builtin-trace.c +++ b/tools/perf/builtin-trace.c @@ -113,6 +113,7 @@ struct syscall_arg_fmt { bool show_zero; #ifdef HAVE_LIBBPF_SUPPORT const struct btf_type *type; + int type_id; #endif }; @@ -851,6 +852,11 @@ static size_t syscall_arg__scnprintf_filename(char *bf, size_t size, #define SCA_FILENAME syscall_arg__scnprintf_filename +static size_t syscall_arg__scnprintf_buf(char *bf, size_t size, + struct syscall_arg *arg); + +#define SCA_BUF syscall_arg__scnprintf_buf + static size_t syscall_arg__scnprintf_pipe_flags(char *bf, size_t size, struct syscall_arg *arg) { @@ -930,6 +936,24 @@ static void syscall_arg_fmt__cache_btf_enum(struct syscall_arg_fmt *arg_fmt, str arg_fmt->type = btf__type_by_id(btf, id); } +static int syscall_arg_fmt__cache_btf_struct(struct syscall_arg_fmt *arg_fmt, struct btf *btf, char *type) +{ + /* this function is solely used in trace__bpf_sys_enter_beauty_map */ + int id; + + if (arg_fmt->type != NULL) + return -1; + + id = btf__find_by_name(btf, type); + if (id < 0) + return -1; + + arg_fmt->type_id = id; /* used for dumping data later */ + arg_fmt->type = btf__type_by_id(btf, id); + + return 0; +} + static bool syscall_arg__strtoul_btf_enum(char *bf, size_t size, struct syscall_arg *arg, u64 *val) { const struct btf_type *bt = arg->fmt->type; @@ -991,8 +1015,56 @@ static size_t btf_enum_scnprintf(const struct btf_type *type, struct btf *btf, c return 0; } +#define DUMPSIZ 256 + +static void btf_dump_snprintf(void *ctx, const char *fmt, va_list args) +{ + char *s = ctx, new[DUMPSIZ]; + + vsnprintf(new, DUMPSIZ, fmt, args); + + if (strlen(s) + strlen(new) < DUMPSIZ) + strncat(s, new, DUMPSIZ); +} + +static size_t btf_dump__struct_scnprintf(const struct btf_type *type, struct btf *btf, char *bf, size_t size, struct syscall_arg *arg, int type_id) +{ + char str[DUMPSIZ]; + int dump_size; + int consumed; + struct btf_dump *btf_dump; + struct augmented_arg *augmented_arg = arg->augmented.args; + LIBBPF_OPTS(btf_dump_opts, dump_opts); + LIBBPF_OPTS(btf_dump_type_data_opts, dump_data_opts); + + if (arg == NULL || arg->augmented.args == NULL) + return 0; + + memset(str, 0, sizeof(str)); + + dump_data_opts.compact = true; + dump_data_opts.skip_names = true; + + btf_dump = btf_dump__new(btf, btf_dump_snprintf, str, &dump_opts); + if (btf_dump == NULL) + return 0; + + consumed = sizeof(*augmented_arg) + augmented_arg->size; + + dump_size = btf_dump__dump_type_data(btf_dump, type_id, arg->augmented.args->value, type->size, &dump_data_opts); + if (dump_size == 0) + return 0; + + arg->augmented.args = ((void *)arg->augmented.args) + consumed; + arg->augmented.size -= consumed; + + btf_dump__free(btf_dump); + + return scnprintf(bf, size, "%s", str); +} + static size_t trace__btf_scnprintf(struct trace *trace, struct syscall_arg_fmt *arg_fmt, char *bf, - size_t size, int val, char *type) + size_t size, int val, struct syscall_arg *arg, char *type) { if (trace->btf == NULL) return 0; @@ -1008,6 +1080,8 @@ static size_t trace__btf_scnprintf(struct trace *trace, struct syscall_arg_fmt * if (btf_is_enum(arg_fmt->type)) return btf_enum_scnprintf(arg_fmt->type, trace->btf, bf, size, val); + else if (btf_is_struct(arg_fmt->type)) + return btf_dump__struct_scnprintf(arg_fmt->type, trace->btf, bf, size, arg, arg_fmt->type_id); return 0; } @@ -1694,6 +1768,53 @@ static size_t syscall_arg__scnprintf_filename(char *bf, size_t size, return 0; } +#define MAX_CONTROL_CHAR 31 +#define MAX_ASCII 127 +#define MAX_BUF 32 + +static size_t syscall_arg__scnprintf_augmented_buf(struct syscall_arg *arg, char *bf, size_t size) +{ + struct augmented_arg *augmented_arg = arg->augmented.args; + size_t printed = 0; + unsigned char *start = (unsigned char *)augmented_arg->value; + int i = 0, n = augmented_arg->size, consumed, digits; + char tmp[MAX_BUF * 4], tens[4]; + + memset(tmp, 0, sizeof(tmp)); + + for (int j = 0; j < n && i < (int)sizeof(tmp); ++j) { + /* print control characters(0~31 and 127), and characters bigger than 127 in \ */ + if (start[j] <= MAX_CONTROL_CHAR || start[j] > MAX_ASCII) { + tmp[i++] = '\\'; + digits = scnprintf(tens, sizeof(tmp) - i, "%d", (int)start[j]); + if (digits + i <= (int)sizeof(tmp)) { + strncpy(tmp + i, tens, digits); + i += digits; + } + } else { + tmp[i++] = start[j]; + } + } + + printed = scnprintf(bf, size, "\"%s\"", tmp); + + consumed = sizeof(*augmented_arg) + augmented_arg->size; + + arg->augmented.args = ((void *)arg->augmented.args) + consumed; + arg->augmented.size -= consumed; + + return printed; +} + +static size_t syscall_arg__scnprintf_buf(char *bf, size_t size, + struct syscall_arg *arg) +{ + if (arg->augmented.args) + return syscall_arg__scnprintf_augmented_buf(arg, bf, size); + + return 0; +} + static bool trace__filter_duration(struct trace *trace, double t) { return t < (trace->duration_filter * NSEC_PER_MSEC); @@ -1903,8 +2024,16 @@ syscall_arg_fmt__init_array(struct syscall_arg_fmt *arg, struct tep_format_field if (strcmp(field->type, "const char *") == 0 && ((len >= 4 && strcmp(field->name + len - 4, "name") == 0) || - strstr(field->name, "path") != NULL)) + strstr(field->name, "path") || + strstr(field->name, "file") || + strstr(field->name, "root") || + strstr(field->name, "key") || + strstr(field->name, "special") || + strstr(field->name, "type") || + strstr(field->name, "description"))) arg->scnprintf = SCA_FILENAME; + else if (strstr(field->type, "char *") && strstr(field->name, "buf")) + arg->scnprintf = SCA_BUF; else if ((field->flags & TEP_FIELD_IS_POINTER) || strstr(field->name, "addr")) arg->scnprintf = SCA_PTR; else if (strcmp(field->type, "pid_t") == 0) @@ -2263,7 +2392,7 @@ static size_t syscall__scnprintf_args(struct syscall *sc, char *bf, size_t size, printed += scnprintf(bf + printed, size - printed, "%s: ", field->name); btf_printed = trace__btf_scnprintf(trace, &sc->arg_fmt[arg.idx], bf + printed, - size - printed, val, field->type); + size - printed, val, &arg, field->type); if (btf_printed) { printed += btf_printed; continue; @@ -2965,7 +3094,7 @@ static size_t trace__fprintf_tp_fields(struct trace *trace, struct evsel *evsel, if (trace->show_arg_names) printed += scnprintf(bf + printed, size - printed, "%s: ", field->name); - btf_printed = trace__btf_scnprintf(trace, arg, bf + printed, size - printed, val, field->type); + btf_printed = trace__btf_scnprintf(trace, arg, bf + printed, size - printed, val, NULL, field->type); if (btf_printed) { printed += btf_printed; continue; @@ -3523,6 +3652,82 @@ static int trace__bpf_prog_sys_exit_fd(struct trace *trace, int id) return sc ? bpf_program__fd(sc->bpf_prog.sys_exit) : bpf_program__fd(trace->skel->progs.syscall_unaugmented); } +static int trace__bpf_sys_enter_beauty_map(struct trace *trace, int key, unsigned int *beauty_array) +{ + struct tep_format_field *field; + struct syscall *sc = trace__syscall_info(trace, NULL, key); + const struct btf_type *bt; + char *struct_offset, *tmp, name[32]; + bool augmented = false; + int i, cnt; + + if (sc == NULL) + return -1; + + trace__load_vmlinux_btf(trace); + if (trace->btf == NULL) + return -1; + + for (i = 0, field = sc->args; field; ++i, field = field->next) { + struct_offset = strstr(field->type, "struct "); + + if (field->flags & TEP_FIELD_IS_POINTER && struct_offset) { /* struct */ + struct_offset += 7; + + /* for 'struct foo *', we only want 'foo' */ + for (tmp = struct_offset, cnt = 0; *tmp != ' ' && *tmp != '\0'; ++tmp, ++cnt) { + } + + strncpy(name, struct_offset, cnt); + name[cnt] = '\0'; + + if (syscall_arg_fmt__cache_btf_struct(&sc->arg_fmt[i], trace->btf, name)) + continue; + + bt = sc->arg_fmt[i].type; + beauty_array[i] = bt->size; + augmented = true; + } else if (field->flags & TEP_FIELD_IS_POINTER && /* string */ + strcmp(field->type, "const char *") == 0 && + (strstr(field->name, "name") || + strstr(field->name, "path") || + strstr(field->name, "file") || + strstr(field->name, "root") || + strstr(field->name, "key") || + strstr(field->name, "special") || + strstr(field->name, "type") || + strstr(field->name, "description"))) { + beauty_array[i] = 1; + augmented = true; + } else if (field->flags & TEP_FIELD_IS_POINTER && /* buffer */ + strstr(field->type, "char *") && + (strstr(field->name, "buf") || + strstr(field->name, "val") || + strstr(field->name, "msg"))) { + int j; + struct tep_format_field *field_tmp; + + /* find the size of the buffer */ + for (j = 0, field_tmp = sc->args; field_tmp; ++j, field_tmp = field_tmp->next) { + if (!(field_tmp->flags & TEP_FIELD_IS_POINTER) && /* only integers */ + (strstr(field_tmp->name, "count") || + strstr(field_tmp->name, "siz") || /* size, bufsiz */ + (strstr(field_tmp->name, "len") && strcmp(field_tmp->name, "filename")))) { + /* filename's got 'len' in it, we don't want that */ + beauty_array[i] = -(j + 1); + augmented = true; + break; + } + } + } + } + + if (augmented) + return 0; + + return -1; +} + static struct bpf_program *trace__find_usable_bpf_prog_entry(struct trace *trace, struct syscall *sc) { struct tep_format_field *field, *candidate_field; @@ -3627,7 +3832,9 @@ static int trace__init_syscalls_bpf_prog_array_maps(struct trace *trace) { int map_enter_fd = bpf_map__fd(trace->skel->maps.syscalls_sys_enter); int map_exit_fd = bpf_map__fd(trace->skel->maps.syscalls_sys_exit); + int beauty_map_fd = bpf_map__fd(trace->skel->maps.beauty_map_enter); int err = 0; + unsigned int beauty_array[6]; for (int i = 0; i < trace->sctbl->syscalls.nr_entries; ++i) { int prog_fd, key = syscalltbl__id_at_idx(trace->sctbl, i); @@ -3646,6 +3853,15 @@ static int trace__init_syscalls_bpf_prog_array_maps(struct trace *trace) err = bpf_map_update_elem(map_exit_fd, &key, &prog_fd, BPF_ANY); if (err) break; + + /* set up the size of struct pointer argument for beauty map */ + memset(beauty_array, 0, sizeof(beauty_array)); + err = trace__bpf_sys_enter_beauty_map(trace, key, (unsigned int *)beauty_array); + if (err) + continue; + err = bpf_map_update_elem(beauty_map_fd, &key, beauty_array, BPF_ANY); + if (err) + break; } /* @@ -3714,6 +3930,33 @@ static int trace__init_syscalls_bpf_prog_array_maps(struct trace *trace) return err; } + +static void trace__init_pid_filter(struct trace *trace) +{ + int pid_filter_fd = bpf_map__fd(trace->skel->maps.pid_filter); + bool exists = true; + struct str_node *pos; + struct strlist *pid_slist = strlist__new(trace->opts.target.pid, NULL); + + trace->skel->bss->filter_pid = false; + + if (pid_slist) { + strlist__for_each_entry(pos, pid_slist) { + char *end_ptr; + int pid = strtol(pos->s, &end_ptr, 10); + + if (pid == INT_MIN || pid == INT_MAX || + (*end_ptr != '\0' && *end_ptr != ',')) + continue; + + bpf_map_update_elem(pid_filter_fd, &pid, &exists, BPF_ANY); + trace->skel->bss->filter_pid = true; + } + } + + strlist__delete(pid_slist); +} + #endif // HAVE_BPF_SKEL static int trace__set_ev_qualifier_filter(struct trace *trace) @@ -4108,6 +4351,9 @@ static int trace__run(struct trace *trace, int argc, const char **argv) #ifdef HAVE_BPF_SKEL if (trace->skel && trace->skel->progs.sys_enter) trace__init_syscalls_bpf_prog_array_maps(trace); + + if (trace->skel) + trace__init_pid_filter(trace); #endif if (trace->ev_qualifier_ids.nr > 0) { -- 2.45.2