From nobody Tue Oct 11 22:35:37 2022 X-Original-To: dev-commits-src-all@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id 4Mn9bZ6z1Xz4fZRb; Tue, 11 Oct 2022 22:35:38 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "R3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4Mn9bZ18xcz3ZrF; Tue, 11 Oct 2022 22:35:38 +0000 (UTC) (envelope-from git@FreeBSD.org) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1665527738; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=AQqOtVsyPC0T0JDNAzHbzHSJLvItJvPKMAtBc+xbtHY=; b=QmsfuoDGUxigfYkNyx22ZVvnOHCLMQdopdB/iyUc+WZgeTkt5X+54hsI+msM66JII6mC8v c9v0gXfR8PGIbfCbtv7VOw9YgbZutLn6V1BQ0S8WO4rRCj1qxSsXLG3/XgdOZECWUXBiph B0PSWSG7VjkSQgN+yG0iHTBqPg8DXdfePAhKgDRJKALV6W0tYjc/o7bbVZOGtzHjk29ctV 5ZOTvjlj539MhdERsG1vg42uY1iLrOWvDgBAs+E1jYB1yAjMwFVNilSPC2o2m3yC251GvJ /r6DjSoQ5RCPuk+wwf06agOZrIOhqV2rtOe4nLZ575gIJWAUysN1QgXg4JUNiQ== Received: from gitrepo.freebsd.org (gitrepo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:5]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id 4Mn9bZ0GYDz16FG; Tue, 11 Oct 2022 22:35:38 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from gitrepo.freebsd.org ([127.0.1.44]) by gitrepo.freebsd.org (8.16.1/8.16.1) with ESMTP id 29BMZb3D048827; Tue, 11 Oct 2022 22:35:37 GMT (envelope-from git@gitrepo.freebsd.org) Received: (from git@localhost) by gitrepo.freebsd.org (8.16.1/8.16.1/Submit) id 29BMZbmF048826; Tue, 11 Oct 2022 22:35:37 GMT (envelope-from git) Date: Tue, 11 Oct 2022 22:35:37 GMT Message-Id: <202210112235.29BMZbmF048826@gitrepo.freebsd.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-main@FreeBSD.org From: Mark Johnston Subject: git: 6f6d1fc7c8e5 - main - kinst: Add a manual page List-Id: Commit messages for all branches of the src repository List-Archive: https://lists.freebsd.org/archives/dev-commits-src-all List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-dev-commits-src-all@freebsd.org X-BeenThere: dev-commits-src-all@freebsd.org MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Git-Committer: markj X-Git-Repository: src X-Git-Refname: refs/heads/main X-Git-Reftype: branch X-Git-Commit: 6f6d1fc7c8e5e5ffc5484abcf95d34b1a2434a2b Auto-Submitted: auto-generated ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1665527738; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=AQqOtVsyPC0T0JDNAzHbzHSJLvItJvPKMAtBc+xbtHY=; b=DCwa/pL5oZ5zefhBmzLmbHCJTNI+g830f3doGKY1DGxbhGrxYV+gcYEVmuRFF2YjkD4f0K SOyVFyOlcpHOOs9qKxtAW2X9HGvUhEVsKUJRpzRZGkSFVtI1Zj0gbdeAV+QmmpaddynLNV tvF174UR1lCJ7VoidmMzn8Z9QrJ2a5nQvFEx1xwVmH7TovA/59/9hn3565mIuhLx1uilIx ZEFII7uyejvJoDkcEynpUUsRMuVngbZfdrdzOe4UdTqEuFEmRz9A88x1euxYJ3MDGBxLJQ nDoy7JLCuqVgYjN+S1KkFHwS9M4zERf53Sjr/LRggYPRZVmhYmtIzIweMF0D8Q== ARC-Seal: i=1; s=dkim; d=freebsd.org; t=1665527738; a=rsa-sha256; cv=none; b=kLSaLGVwMTkRH3ko3lB1qM8/nwfqI42+4YX/IZ0q0lrkf3Sx3Tqoqb57SayJvT3ty45xYd 1P0Ei0Hs81EI/ctIZzhQ1aCZUIKway3n8inISsIsVOGRfoCckDsRmJXxm0a3aGJvAVxCrC NoeNe2mrjz4XNUBp5PfkVn8Lf4F/bl5rLzrZcYCEjh6Y0fbI/8GqA98gNgX7fcYAiX06D8 p13TmH+/SEjIuWLxl/dzKyDLsjaDxNXv2hPvs5zBz6mqy+fRiJXP4GGgH3Dc3QbWHDWkWz Fue4w/jar4fab+RN9wTWolMneAlGoyk7wR6VZceYeVC91iF+0PR4nhKOc37wdA== ARC-Authentication-Results: i=1; mx1.freebsd.org; none X-ThisMailContainsUnwantedMimeParts: N The branch main has been updated by markj: URL: https://cgit.FreeBSD.org/src/commit/?id=6f6d1fc7c8e5e5ffc5484abcf95d34b1a2434a2b commit 6f6d1fc7c8e5e5ffc5484abcf95d34b1a2434a2b Author: Christos Margiolis AuthorDate: 2022-10-11 15:34:19 +0000 Commit: Mark Johnston CommitDate: 2022-10-11 22:19:08 +0000 kinst: Add a manual page MFC after: 3 months Sponsored by: Google, Inc. (GSoC 2022) Differential Revision: https://reviews.freebsd.org/D36853 --- share/man/man4/Makefile | 1 + share/man/man4/dtrace_kinst.4 | 89 +++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 90 insertions(+) diff --git a/share/man/man4/Makefile b/share/man/man4/Makefile index 192bab4155a2..4fca8065fb4a 100644 --- a/share/man/man4/Makefile +++ b/share/man/man4/Makefile @@ -917,6 +917,7 @@ _ccd.4= ccd.4 _dtrace_provs= dtrace_audit.4 \ dtrace_io.4 \ dtrace_ip.4 \ + dtrace_kinst.4 \ dtrace_lockstat.4 \ dtrace_proc.4 \ dtrace_sched.4 \ diff --git a/share/man/man4/dtrace_kinst.4 b/share/man/man4/dtrace_kinst.4 new file mode 100644 index 000000000000..48253add6855 --- /dev/null +++ b/share/man/man4/dtrace_kinst.4 @@ -0,0 +1,89 @@ +.\" Copyright (c) 2022 Christos Margiolis +.\" All rights reserved. +.\" +.\" Redistribution and use in source and binary forms, with or without +.\" modification, are permitted provided that the following conditions +.\" are met: +.\" 1. Redistributions of source code must retain the above copyright +.\" notice, this list of conditions and the following disclaimer. +.\" 2. Redistributions in binary form must reproduce the above copyright +.\" notice, this list of conditions and the following disclaimer in the +.\" documentation and/or other materials provided with the distribution. +.\" +.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND +.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE +.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE +.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE +.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL +.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS +.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) +.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT +.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY +.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF +.\" SUCH DAMAGE. +.\" +.\" $FreeBSD$ +.\" +.Dd October 01, 2022 +.Dt DTRACE_KINST 4 +.Os +.Sh NAME +.Nm dtrace_kinst +.Nd a DTrace provider for tracing arbitrary instructions in a given kernel +function. +.Sh SYNOPSIS +kinst::: +.Sh DESCRIPTION +.Pp +The DTrace +.Nm kinst +provider allows the user to trace any instruction in a given kernel function. + corresponds to the function to be traced, and is the +offset to the specific instruction, and can be obtained from the function's +disassembly using +.Xr kgdb 1 . +.Pp +.Nm kinst +creates probes on-demand, meaning it searches for and parses the function's +instructions each time +.Xr dtrace 1 +is run, and not at module load time. This is in contrast to FBT's load-time +parsing, since +.Nm kinst +can potentially create thousands of probes for just a single function, instead +of up to two (entry and return) in the case of FBT. +.Sh EXAMPLES +.Pp +Find the offset to the third instruction in +.Fn vm_fault +and trace it: +.Bd -literal -offset indent +# kgdb +(kgdb) disas /r vm_fault +Dump of assembler code for function vm_fault: + 0xffffffff80876df0 <+0>: 55 push %rbp + 0xffffffff80876df1 <+1>: 48 89 e5 mov %rsp,%rbp + 0xffffffff80876df4 <+4>: 41 57 push %r15 + +# dtrace -n 'kinst::vm_fault:4' +.Ed +.Pp +Trace all instructions in +.Fn amd64_syscall : +.Bd -literal -offset indent +# dtrace -n 'kinst::amd64_syscall:' +.Ed +.Sh IMPLEMENTATION NOTES +The provider is currently implemented only for amd64. +.Sh SEE ALSO +.Xr dtrace 1 , +.Xr kgdb 1 +.Sh HISTORY +The +.Nm kinst +provider first appeared in +.Fx +14.0. +.Sh AUTHORS +This manual page was written by +.An Christos Margiolis Aq Mt christos@FreeBSD.org .