From patchwork Mon Aug 26 03:19:11 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Masami Hiramatsu (Google)" X-Patchwork-Id: 11113925 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 03C6D1398 for ; Mon, 26 Aug 2019 03:19:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CC02021744 for ; Mon, 26 Aug 2019 03:19:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1566789561; bh=2hqvqjb4JRbv59jAzcU+dKYGR+NXhgzGBeJ3dWiVhdU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=NNws7mLVb3oXnKjIn+m1SjvpoGHtldRFL8+wzxlw3eNSPNW6DlkpBGHWxjQ1KluMf 43MNPauB+N644L568RFZ41ZmGpwM7hSw8tefUtBNX05SiA+2YTgxgmuAyAo0G2jf/E RW1Y3A3vAUAaWGebP7LX1AOHDx8lHgvkdhGim9eE= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729716AbfHZDTU (ORCPT ); Sun, 25 Aug 2019 23:19:20 -0400 Received: from mail.kernel.org ([198.145.29.99]:37774 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729437AbfHZDTT (ORCPT ); Sun, 25 Aug 2019 23:19:19 -0400 Received: from localhost.localdomain (NE2965lan1.rev.em-net.ne.jp [210.141.244.193]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id D93F62070B; Mon, 26 Aug 2019 03:19:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1566789558; bh=2hqvqjb4JRbv59jAzcU+dKYGR+NXhgzGBeJ3dWiVhdU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=sv3Fvm/tvtHGU71iCv0m7liX43HCg8VeHCygpsU35XNGDMcGKWwzDKrdw0yE++5e9 4zMTqUPTQEVCGxT8rerpMrq4uDWrQflAwvew7Hfec2BvYNDOU8449nhhOMEIJMLIof lpS7xvOCoO9y4pwtelBgIa7XhQD2W53kVMkXZ8jE= From: Masami Hiramatsu To: Steven Rostedt , Frank Rowand Cc: Ingo Molnar , Namhyung Kim , Tim Bird , Jiri Olsa , Arnaldo Carvalho de Melo , Tom Zanussi , Rob Herring , Andrew Morton , Thomas Gleixner , Greg Kroah-Hartman , Alexey Dobriyan , Jonathan Corbet , Linus Torvalds , linux-doc@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [RFC PATCH v3 18/19] tracing/boot: Add function-graph tracer options Date: Mon, 26 Aug 2019 12:19:11 +0900 Message-Id: <156678955140.21459.9556721429972023089.stgit@devnote2> X-Mailer: git-send-email 2.20.1 In-Reply-To: <156678933823.21459.4100380582025186209.stgit@devnote2> References: <156678933823.21459.4100380582025186209.stgit@devnote2> User-Agent: StGit/0.17.1-dirty MIME-Version: 1.0 Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org Add following function-graph tracer related options - ftrace.fgraph.filters = FILTER[, FILTER2...]; Add fgraph tracing function filters. - ftrace.fgraph.notraces = FILTER[, FILTER2...]; Add fgraph non tracing function filters. - ftrace.fgraph.max_depth = MAX_DEPTH; Set MAX_DEPTH to maximum depth of fgraph tracer. Note that these properties are available on ftrace global node only, because these filters are globally applied. Signed-off-by: Masami Hiramatsu --- kernel/trace/ftrace.c | 85 +++++++++++++++++++++++++++++---------------- kernel/trace/trace_boot.c | 71 ++++++++++++++++++++++++++++++++++++++ 2 files changed, 126 insertions(+), 30 deletions(-) diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index eca34503f178..e016ce12e60a 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -1241,7 +1241,7 @@ static void clear_ftrace_mod_list(struct list_head *head) mutex_unlock(&ftrace_lock); } -static void free_ftrace_hash(struct ftrace_hash *hash) +void free_ftrace_hash(struct ftrace_hash *hash) { if (!hash || hash == EMPTY_HASH) return; @@ -4897,7 +4897,7 @@ __setup("ftrace_filter=", set_ftrace_filter); #ifdef CONFIG_FUNCTION_GRAPH_TRACER static char ftrace_graph_buf[FTRACE_FILTER_SIZE] __initdata; static char ftrace_graph_notrace_buf[FTRACE_FILTER_SIZE] __initdata; -static int ftrace_graph_set_hash(struct ftrace_hash *hash, char *buffer); +int ftrace_graph_set_hash(struct ftrace_hash *hash, char *buffer); static int __init set_graph_function(char *str) { @@ -5226,6 +5226,26 @@ __ftrace_graph_open(struct inode *inode, struct file *file, return ret; } +struct ftrace_hash *ftrace_graph_copy_hash(bool enable) +{ + struct ftrace_hash *hash; + + mutex_lock(&graph_lock); + + if (enable) + hash = rcu_dereference_protected(ftrace_graph_hash, + lockdep_is_held(&graph_lock)); + else + hash = rcu_dereference_protected(ftrace_graph_notrace_hash, + lockdep_is_held(&graph_lock)); + + hash = alloc_and_copy_ftrace_hash(FTRACE_HASH_DEFAULT_BITS, hash); + + mutex_unlock(&graph_lock); + + return hash; +} + static int ftrace_graph_open(struct inode *inode, struct file *file) { @@ -5282,11 +5302,40 @@ ftrace_graph_notrace_open(struct inode *inode, struct file *file) return ret; } +int ftrace_graph_apply_hash(struct ftrace_hash *hash, bool enable) +{ + struct ftrace_hash *old_hash, *new_hash; + + new_hash = __ftrace_hash_move(hash); + if (!new_hash) + return -ENOMEM; + + mutex_lock(&graph_lock); + + if (enable) { + old_hash = rcu_dereference_protected(ftrace_graph_hash, + lockdep_is_held(&graph_lock)); + rcu_assign_pointer(ftrace_graph_hash, new_hash); + } else { + old_hash = rcu_dereference_protected(ftrace_graph_notrace_hash, + lockdep_is_held(&graph_lock)); + rcu_assign_pointer(ftrace_graph_notrace_hash, new_hash); + } + + mutex_unlock(&graph_lock); + + /* Wait till all users are no longer using the old hash */ + synchronize_rcu(); + + free_ftrace_hash(old_hash); + + return 0; +} + static int ftrace_graph_release(struct inode *inode, struct file *file) { struct ftrace_graph_data *fgd; - struct ftrace_hash *old_hash, *new_hash; struct trace_parser *parser; int ret = 0; @@ -5311,41 +5360,17 @@ ftrace_graph_release(struct inode *inode, struct file *file) trace_parser_put(parser); - new_hash = __ftrace_hash_move(fgd->new_hash); - if (!new_hash) { - ret = -ENOMEM; - goto out; - } - - mutex_lock(&graph_lock); - - if (fgd->type == GRAPH_FILTER_FUNCTION) { - old_hash = rcu_dereference_protected(ftrace_graph_hash, - lockdep_is_held(&graph_lock)); - rcu_assign_pointer(ftrace_graph_hash, new_hash); - } else { - old_hash = rcu_dereference_protected(ftrace_graph_notrace_hash, - lockdep_is_held(&graph_lock)); - rcu_assign_pointer(ftrace_graph_notrace_hash, new_hash); - } - - mutex_unlock(&graph_lock); - - /* Wait till all users are no longer using the old hash */ - synchronize_rcu(); - - free_ftrace_hash(old_hash); + ret = ftrace_graph_apply_hash(fgd->new_hash, + fgd->type == GRAPH_FILTER_FUNCTION); } - out: free_ftrace_hash(fgd->new_hash); kfree(fgd); return ret; } -static int -ftrace_graph_set_hash(struct ftrace_hash *hash, char *buffer) +int ftrace_graph_set_hash(struct ftrace_hash *hash, char *buffer) { struct ftrace_glob func_g; struct dyn_ftrace *rec; diff --git a/kernel/trace/trace_boot.c b/kernel/trace/trace_boot.c index 942ca8d3fcc8..b32688032d36 100644 --- a/kernel/trace/trace_boot.c +++ b/kernel/trace/trace_boot.c @@ -72,6 +72,75 @@ trace_boot_set_instance_options(struct trace_array *tr, struct skc_node *node) } } +#ifdef CONFIG_FUNCTION_GRAPH_TRACER +extern unsigned int fgraph_max_depth; +extern struct ftrace_hash *ftrace_graph_copy_hash(bool enable); +extern int ftrace_graph_set_hash(struct ftrace_hash *hash, char *buffer); +extern int ftrace_graph_apply_hash(struct ftrace_hash *hash, bool enable); +extern void free_ftrace_hash(struct ftrace_hash *hash); + +static void __init +trace_boot_set_fgraph_filter(struct skc_node *node, const char *option, + bool enable) +{ + struct ftrace_hash *hash; + struct skc_node *anode; + const char *p; + char *q; + int err; + bool updated = false; + + hash = ftrace_graph_copy_hash(enable); + if (!hash) { + pr_err("Failed to copy fgraph hash\n"); + return; + } + skc_node_for_each_array_value(node, option, anode, p) { + q = kstrdup(p, GFP_KERNEL); + if (!q) + goto free_hash; + err = ftrace_graph_set_hash(hash, q); + kfree(q); + if (err) + pr_err("Failed to add %s: %s\n", option, p); + else + updated = true; + } + if (!updated) + goto free_hash; + + if (ftrace_graph_apply_hash(hash, enable) < 0) + pr_err("Failed to apply new fgraph hash\n"); + else { + /* If succeeded to apply new hash, old hash is released */ + return; + } + +free_hash: + free_ftrace_hash(hash); +} + +static void __init +trace_boot_set_fgraph_options(struct skc_node *node) +{ + const char *p; + unsigned long v; + + node = skc_node_find_child(node, "fgraph"); + if (!node) + return; + + trace_boot_set_fgraph_filter(node, "filters", true); + trace_boot_set_fgraph_filter(node, "notraces", false); + + p = skc_node_find_value(node, "max_depth", NULL); + if (p && *p != '\0' && !kstrtoul(p, 0, &v)) + fgraph_max_depth = (unsigned int)v; +} +#else +#define trace_boot_set_fgraph_options(node) do {} while (0) +#endif + static void __init trace_boot_set_global_options(struct trace_array *tr, struct skc_node *node) { @@ -98,6 +167,8 @@ trace_boot_set_global_options(struct trace_array *tr, struct skc_node *node) if (skc_node_find_value(node, "alloc_snapshot", NULL)) if (tracing_alloc_snapshot() < 0) pr_err("Failed to allocate snapshot buffer\n"); + + trace_boot_set_fgraph_options(node); } #ifdef CONFIG_EVENT_TRACING