From patchwork Tue Jan 18 20:43:16 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Beau Belgrave X-Patchwork-Id: 12716887 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id CD57FC433F5 for ; Tue, 18 Jan 2022 20:43:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1345737AbiARUnc (ORCPT ); Tue, 18 Jan 2022 15:43:32 -0500 Received: from linux.microsoft.com ([13.77.154.182]:43808 "EHLO linux.microsoft.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1343795AbiARUnb (ORCPT ); Tue, 18 Jan 2022 15:43:31 -0500 Received: from localhost.localdomain (c-73-140-2-214.hsd1.wa.comcast.net [73.140.2.214]) by linux.microsoft.com (Postfix) with ESMTPSA id 17B2F20B927A; Tue, 18 Jan 2022 12:43:31 -0800 (PST) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com 17B2F20B927A DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1642538611; bh=vu/vJHWme19QraNNv1lNg+FIaAp6zN63Emht5YXcox8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Uh/uP7s7OwpoZnpLPF9VPv1QvBVFJAiNtCjmudYZ3CmQQDiIfrwYygVWJ+GTXtvl0 hVWyDHDv3Of9fJkZz37tW0IsDYDX2VbxohmJ8YRraxC1o35/h4Ny8QCfLyOXq+vFdl QYcSbkLodtNEwCQufZk7s5hjY9g3xf2EozGH4voI= From: Beau Belgrave To: rostedt@goodmis.org, mhiramat@kernel.org Cc: linux-trace-devel@vger.kernel.org, linux-kernel@vger.kernel.org, beaub@linux.microsoft.com Subject: [PATCH v10 02/12] user_events: Add print_fmt generation support for basic types Date: Tue, 18 Jan 2022 12:43:16 -0800 Message-Id: <20220118204326.2169-3-beaub@linux.microsoft.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20220118204326.2169-1-beaub@linux.microsoft.com> References: <20220118204326.2169-1-beaub@linux.microsoft.com> Precedence: bulk List-ID: X-Mailing-List: linux-trace-devel@vger.kernel.org Addes print_fmt format generation for basic types that are supported for user processes. Only supports sizes that are the same on 32 and 64 bit. Signed-off-by: Beau Belgrave --- kernel/trace/trace_events_user.c | 115 ++++++++++++++++++++++++++++++- 1 file changed, 113 insertions(+), 2 deletions(-) diff --git a/kernel/trace/trace_events_user.c b/kernel/trace/trace_events_user.c index 77105233115e..ddc5c3cf1bf8 100644 --- a/kernel/trace/trace_events_user.c +++ b/kernel/trace/trace_events_user.c @@ -359,6 +359,114 @@ static int user_event_parse_fields(struct user_event *user, char *args) static struct trace_event_fields user_event_fields_array[1]; +static const char *user_field_format(const char *type) +{ + if (strcmp(type, "s64") == 0) + return "%lld"; + if (strcmp(type, "u64") == 0) + return "%llu"; + if (strcmp(type, "s32") == 0) + return "%d"; + if (strcmp(type, "u32") == 0) + return "%u"; + if (strcmp(type, "int") == 0) + return "%d"; + if (strcmp(type, "unsigned int") == 0) + return "%u"; + if (strcmp(type, "s16") == 0) + return "%d"; + if (strcmp(type, "u16") == 0) + return "%u"; + if (strcmp(type, "short") == 0) + return "%d"; + if (strcmp(type, "unsigned short") == 0) + return "%u"; + if (strcmp(type, "s8") == 0) + return "%d"; + if (strcmp(type, "u8") == 0) + return "%u"; + if (strcmp(type, "char") == 0) + return "%d"; + if (strcmp(type, "unsigned char") == 0) + return "%u"; + if (strstr(type, "char[") != 0) + return "%s"; + + /* Unknown, likely struct, allowed treat as 64-bit */ + return "%llu"; +} + +static bool user_field_is_dyn_string(const char *type, const char **str_func) +{ + if (str_has_prefix(type, "__data_loc ")) { + *str_func = "__get_str"; + goto check; + } + + if (str_has_prefix(type, "__rel_loc ")) { + *str_func = "__get_rel_str"; + goto check; + } + + return false; +check: + return strstr(type, "char") != 0; +} + +#define LEN_OR_ZERO (len ? len - pos : 0) +static int user_event_set_print_fmt(struct user_event *user, char *buf, int len) +{ + struct ftrace_event_field *field, *next; + struct list_head *head = &user->fields; + int pos = 0, depth = 0; + const char *str_func; + + pos += snprintf(buf + pos, LEN_OR_ZERO, "\""); + + list_for_each_entry_safe_reverse(field, next, head, link) { + if (depth != 0) + pos += snprintf(buf + pos, LEN_OR_ZERO, " "); + + pos += snprintf(buf + pos, LEN_OR_ZERO, "%s=%s", + field->name, user_field_format(field->type)); + + depth++; + } + + pos += snprintf(buf + pos, LEN_OR_ZERO, "\""); + + list_for_each_entry_safe_reverse(field, next, head, link) { + if (user_field_is_dyn_string(field->type, &str_func)) + pos += snprintf(buf + pos, LEN_OR_ZERO, + ", %s(%s)", str_func, field->name); + else + pos += snprintf(buf + pos, LEN_OR_ZERO, + ", REC->%s", field->name); + } + + return pos + 1; +} +#undef LEN_OR_ZERO + +static int user_event_create_print_fmt(struct user_event *user) +{ + char *print_fmt; + int len; + + len = user_event_set_print_fmt(user, NULL, 0); + + print_fmt = kmalloc(len, GFP_KERNEL); + + if (!print_fmt) + return -ENOMEM; + + user_event_set_print_fmt(user, print_fmt, len); + + user->call.print_fmt = print_fmt; + + return 0; +} + static enum print_line_t user_event_print_trace(struct trace_iterator *iter, int flags, struct trace_event *event) @@ -392,6 +500,7 @@ static int destroy_user_event(struct user_event *user) clear_bit(user->index, page_bitmap); hash_del(&user->node); + kfree(user->call.print_fmt); kfree(EVENT_NAME(user)); kfree(user); @@ -669,8 +778,10 @@ static int user_event_parse(char *name, char *args, char *flags, if (ret) goto put_user; - /* Minimal print format */ - user->call.print_fmt = "\"\""; + ret = user_event_create_print_fmt(user); + + if (ret) + goto put_user; user->call.data = user; user->call.class = &user->class;