From patchwork Sun Jun 11 13:00:29 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jiri Olsa X-Patchwork-Id: 13275216 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D9C0733F1 for ; Sun, 11 Jun 2023 13:00:34 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0E93EC433EF; Sun, 11 Jun 2023 13:00:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1686488434; bh=w5GEviuZiSz6ulTNLoenUvOQvB5v/kxoYUOgOfhqU7g=; h=From:To:Cc:Subject:Date:From; b=BaAM7/6YXRn1g/lvATq61O+eRKqA4Ls7KaD2s8I4X4LfW6PIVpQMOgvdMYPf0m3a7 2gqzhFQFGsOnbRKivcBIk/nbuRPCTG0LqhTvg6bpgg3wTQ6gfeVcfoq8dWEAxS57Vk lAYLfx27JXewKrZoeb9Yw6fDI6X0eRbBuXuLKxVKgjn94EZ0B2MFXwSdLXh4Yfgjbj DIKMMNt3ZVLWNSM03fWoOvbRB5/Ylg4EA7CYqbaA1g9dQCgT+9IX15+7E+hDRGdqaD MTMmTgMu+NAhOlzgRev/LeMRlxLQTh0cFoO1hzase3lwL9em0DrZsiyqGLYbLxecv5 7567EaTg46pfA== From: Jiri Olsa To: Steven Rostedt , Masami Hiramatsu , Mark Rutland Cc: Andrii Nakryiko , lkml , linux-trace-kernel@vger.kernel.org, bpf@vger.kernel.org, Andrii Nakryiko , Jackie Liu Subject: [PATCHv2] ftrace: Show all functions with addresses in available_filter_functions_addrs Date: Sun, 11 Jun 2023 15:00:29 +0200 Message-Id: <20230611130029.1202298-1-jolsa@kernel.org> X-Mailer: git-send-email 2.40.1 Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Adding new available_filter_functions_addrs file that shows all available functions (same as available_filter_functions) together with addresses, like: # cat available_filter_functions_addrs | head ffffffff81000770 __traceiter_initcall_level ffffffff810007c0 __traceiter_initcall_start ffffffff81000810 __traceiter_initcall_finish ffffffff81000860 trace_initcall_finish_cb ... Note displayed address is the patch-site address and can differ from /proc/kallsyms address. It's useful to have address avilable for traceable symbols, so we don't need to allways cross check kallsyms with available_filter_functions (or the other way around) and have all the data in single file. For backwards compatibility reasons we can't change the existing available_filter_functions file output, but we need to add new file. Suggested-by: Steven Rostedt (Google) Suggested-by: Andrii Nakryiko Signed-off-by: Jiri Olsa Signed-off-by: Jiri Olsa Signed-off-by: Steven Rostedt (Google) --- Documentation/trace/ftrace.rst | 6 ++++++ include/linux/ftrace.h | 1 + kernel/trace/ftrace.c | 37 ++++++++++++++++++++++++++++++++++ 3 files changed, 44 insertions(+) v2 changes: - simplified address print [Steven] - added doc entry for the new file diff --git a/Documentation/trace/ftrace.rst b/Documentation/trace/ftrace.rst index 027437b745a0..e97573e3fc4a 100644 --- a/Documentation/trace/ftrace.rst +++ b/Documentation/trace/ftrace.rst @@ -324,6 +324,12 @@ of ftrace. Here is a list of some of the key files: "set_graph_function", or "set_graph_notrace". (See the section "dynamic ftrace" below for more details.) + available_filter_functions_addrs: + + Similar to available_filter_functions, but with address displayed + for each function. The displayed address is the patch-site address + and can differ from /proc/kallsyms address. + dyn_ftrace_total_info: This file is for debugging purposes. The number of functions that diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index b23bdd414394..6e372575a8e9 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -633,6 +633,7 @@ enum { FTRACE_ITER_MOD = (1 << 5), FTRACE_ITER_ENABLED = (1 << 6), FTRACE_ITER_TOUCHED = (1 << 7), + FTRACE_ITER_ADDRS = (1 << 8), }; void arch_ftrace_update_code(int command); diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 764668467155..b24c573934af 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -3861,6 +3861,9 @@ static int t_show(struct seq_file *m, void *v) if (!rec) return 0; + if (iter->flags & FTRACE_ITER_ADDRS) + seq_printf(m, "%lx ", rec->ip); + if (print_rec(m, rec->ip)) { /* This should only happen when a rec is disabled */ WARN_ON_ONCE(!(rec->flags & FTRACE_FL_DISABLED)); @@ -3996,6 +3999,30 @@ ftrace_touched_open(struct inode *inode, struct file *file) return 0; } +static int +ftrace_avail_addrs_open(struct inode *inode, struct file *file) +{ + struct ftrace_iterator *iter; + int ret; + + ret = security_locked_down(LOCKDOWN_TRACEFS); + if (ret) + return ret; + + if (unlikely(ftrace_disabled)) + return -ENODEV; + + iter = __seq_open_private(file, &show_ftrace_seq_ops, sizeof(*iter)); + if (!iter) + return -ENOMEM; + + iter->pg = ftrace_pages_start; + iter->flags = FTRACE_ITER_ADDRS; + iter->ops = &global_ops; + + return 0; +} + /** * ftrace_regex_open - initialize function tracer filter files * @ops: The ftrace_ops that hold the hash filters @@ -5916,6 +5943,13 @@ static const struct file_operations ftrace_touched_fops = { .release = seq_release_private, }; +static const struct file_operations ftrace_avail_addrs_fops = { + .open = ftrace_avail_addrs_open, + .read = seq_read, + .llseek = seq_lseek, + .release = seq_release_private, +}; + static const struct file_operations ftrace_filter_fops = { .open = ftrace_filter_open, .read = seq_read, @@ -6377,6 +6411,9 @@ static __init int ftrace_init_dyn_tracefs(struct dentry *d_tracer) trace_create_file("available_filter_functions", TRACE_MODE_READ, d_tracer, NULL, &ftrace_avail_fops); + trace_create_file("available_filter_functions_addrs", TRACE_MODE_READ, + d_tracer, NULL, &ftrace_avail_addrs_fops); + trace_create_file("enabled_functions", TRACE_MODE_READ, d_tracer, NULL, &ftrace_enabled_fops);