From: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
To: Christoph Hellwig <hch@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>,
Peter Zijlstra <peterz@infradead.org>,
Ingo Molnar <mingo@elte.hu>, Steven Rostedt <rostedt@goodmis.org>,
Linux-mm <linux-mm@kvack.org>,
Arnaldo Carvalho de Melo <acme@infradead.org>,
Linus Torvalds <torvalds@linux-foundation.org>,
Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>,
Hugh Dickins <hughd@google.com>, Andi Kleen <andi@firstfloor.org>,
Thomas Gleixner <tglx@linutronix.de>,
Jonathan Corbet <corbet@lwn.net>, Oleg Nesterov <oleg@redhat.com>,
Andrew Morton <akpm@linux-foundation.org>,
Jim Keniston <jkenisto@linux.vnet.ibm.com>,
Roland McGrath <roland@hack.frob.com>,
Ananth N Mavinakayanahalli <ananth@in.ibm.com>,
LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v5 3.1.0-rc4-tip 8/26] x86: analyze instruction and determine fixups.
Date: Tue, 20 Sep 2011 21:53:17 +0100 [thread overview]
Message-ID: <20110920205317.GA1508@stefanha-thinkpad.localdomain> (raw)
In-Reply-To: <20110920181225.GA5149@infradead.org>
On Tue, Sep 20, 2011 at 02:12:25PM -0400, Christoph Hellwig wrote:
> On Tue, Sep 20, 2011 at 06:13:10PM +0100, Stefan Hajnoczi wrote:
> > You've probably thought of this but it would be nice to skip XOL for
> > nops. This would be a common case with static probes (e.g. sdt.h) where
> > the probe template includes a nop where we can easily plant int $0x3.
>
> Do we now have sdt.h support for uprobes? That's one of the killer
> features that always seemed to get postponed.
Not yet but it's a question of doing roughly what SystemTap does to
parse the appropriate ELF sections and then putting those probes into
uprobes.
Masami looked at this and found that SystemTap sdt.h currently requires
an extra userspace memory store in order to activate probes. Each probe
has a "semaphore" 16-bit counter which applications may test before
hitting the probe itself. This is used to avoid overhead in
applications that do expensive argument processing (e.g. creating
strings) for probes.
But this should be solvable so it would be possible to use perf-probe(1)
on a std.h-enabled binary. Some distros already ship such binaries!
Stefan
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>
next prev parent reply other threads:[~2011-09-20 20:53 UTC|newest]
Thread overview: 160+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-09-20 11:59 [PATCH v5 3.1.0-rc4-tip 0/26] Uprobes patchset with perf probe support Srikar Dronamraju
2011-09-20 11:59 ` [PATCH v5 3.1.0-rc4-tip 1/26] uprobes: Auxillary routines to insert, find, delete uprobes Srikar Dronamraju
2011-09-20 15:42 ` Stefan Hajnoczi
2011-09-26 11:18 ` Peter Zijlstra
2011-09-26 11:59 ` Srikar Dronamraju
2011-09-26 11:18 ` Peter Zijlstra
2011-09-26 12:02 ` Srikar Dronamraju
2011-09-26 13:35 ` Peter Zijlstra
2011-09-26 16:19 ` Srikar Dronamraju
2011-09-20 12:00 ` [PATCH v5 3.1.0-rc4-tip 2/26] Uprobes: Allow multiple consumers for an uprobe Srikar Dronamraju
2011-09-26 12:29 ` Peter Zijlstra
2011-09-20 12:00 ` [PATCH v5 3.1.0-rc4-tip 3/26] Uprobes: register/unregister probes Srikar Dronamraju
2011-09-20 16:50 ` Stefan Hajnoczi
2011-09-21 4:07 ` Srikar Dronamraju
2011-09-26 13:15 ` Peter Zijlstra
2011-09-26 13:23 ` Srikar Dronamraju
2011-10-03 12:46 ` Oleg Nesterov
2011-10-05 17:04 ` Srikar Dronamraju
2011-10-05 18:50 ` Oleg Nesterov
2011-10-06 6:51 ` Srikar Dronamraju
2011-10-07 17:03 ` Oleg Nesterov
2011-09-20 12:00 ` [PATCH v5 3.1.0-rc4-tip 4/26] uprobes: Define hooks for mmap/munmap Srikar Dronamraju
2011-09-20 17:03 ` Stefan Hajnoczi
2011-09-21 4:03 ` Srikar Dronamraju
2011-09-26 13:53 ` Peter Zijlstra
2011-09-26 15:44 ` Srikar Dronamraju
2011-09-27 11:37 ` Peter Zijlstra
2011-09-27 13:08 ` Srikar Dronamraju
2011-09-27 11:41 ` Peter Zijlstra
2011-09-27 12:59 ` Srikar Dronamraju
2011-09-27 11:42 ` Peter Zijlstra
2011-10-03 13:37 ` Oleg Nesterov
2011-10-06 11:05 ` Srikar Dronamraju
2011-10-07 17:36 ` Oleg Nesterov
2011-10-10 12:31 ` Srikar Dronamraju
2011-09-20 12:00 ` [PATCH v5 3.1.0-rc4-tip 5/26] Uprobes: copy of the original instruction Srikar Dronamraju
2011-10-03 16:29 ` Oleg Nesterov
2011-10-05 10:52 ` Srikar Dronamraju
2011-10-05 15:11 ` Oleg Nesterov
2011-10-05 16:09 ` Srikar Dronamraju
2011-10-05 17:53 ` Oleg Nesterov
2011-09-20 12:01 ` [PATCH v5 3.1.0-rc4-tip 6/26] Uprobes: define fixups Srikar Dronamraju
2011-09-20 12:01 ` [PATCH v5 3.1.0-rc4-tip 7/26] Uprobes: uprobes arch info Srikar Dronamraju
2011-09-20 12:01 ` [PATCH v5 3.1.0-rc4-tip 8/26] x86: analyze instruction and determine fixups Srikar Dronamraju
2011-09-20 17:13 ` Stefan Hajnoczi
2011-09-20 18:12 ` Christoph Hellwig
2011-09-20 20:53 ` Stefan Hajnoczi [this message]
2011-09-23 11:53 ` Masami Hiramatsu
2011-09-23 16:51 ` Stefan Hajnoczi
2011-09-26 19:59 ` Josh Stone
2011-09-27 1:32 ` Masami Hiramatsu
2011-09-27 2:59 ` Josh Stone
2011-09-27 7:08 ` Stefan Hajnoczi
2011-09-22 1:05 ` Josh Stone
2011-10-05 15:48 ` Oleg Nesterov
2011-10-05 16:12 ` Srikar Dronamraju
2011-09-20 12:01 ` [PATCH v5 3.1.0-rc4-tip 9/26] Uprobes: Background page replacement Srikar Dronamraju
2011-10-05 16:19 ` Oleg Nesterov
2011-10-06 6:53 ` Srikar Dronamraju
2011-09-20 12:01 ` [PATCH v5 3.1.0-rc4-tip 10/26] x86: Set instruction pointer Srikar Dronamraju
2011-10-05 16:29 ` Oleg Nesterov
2011-09-20 12:02 ` [PATCH v5 3.1.0-rc4-tip 11/26] x86: Introduce TIF_UPROBE FLAG Srikar Dronamraju
2011-09-20 12:02 ` [PATCH v5 3.1.0-rc4-tip 12/26] Uprobes: Handle breakpoint and Singlestep Srikar Dronamraju
2011-09-26 13:59 ` Peter Zijlstra
2011-09-26 16:01 ` Srikar Dronamraju
2011-09-26 16:25 ` Peter Zijlstra
2011-10-05 17:48 ` Oleg Nesterov
2011-09-26 14:02 ` Peter Zijlstra
2011-10-07 18:28 ` Oleg Nesterov
2011-10-09 13:31 ` Oleg Nesterov
2011-09-20 12:02 ` [PATCH v5 3.1.0-rc4-tip 13/26] x86: define a x86 specific exception notifier Srikar Dronamraju
2011-09-26 14:19 ` Peter Zijlstra
2011-09-26 15:52 ` Srikar Dronamraju
2011-09-27 11:46 ` Peter Zijlstra
2011-10-07 18:31 ` Oleg Nesterov
2011-09-20 12:02 ` [PATCH v5 3.1.0-rc4-tip 14/26] uprobe: register " Srikar Dronamraju
2011-09-20 12:03 ` [PATCH v5 3.1.0-rc4-tip 15/26] x86: Define x86_64 specific uprobe_task_arch_info structure Srikar Dronamraju
2011-09-20 12:03 ` [PATCH v5 3.1.0-rc4-tip 16/26] uprobes: Introduce " Srikar Dronamraju
2011-09-20 12:03 ` [PATCH v5 3.1.0-rc4-tip 17/26] x86: arch specific hooks for pre/post singlestep handling Srikar Dronamraju
2011-09-26 14:23 ` Peter Zijlstra
2011-09-26 16:34 ` Srikar Dronamraju
2011-09-27 11:44 ` Peter Zijlstra
2011-09-20 12:03 ` [PATCH v5 3.1.0-rc4-tip 18/26] uprobes: slot allocation Srikar Dronamraju
2011-09-27 11:49 ` Peter Zijlstra
2011-09-27 12:32 ` Srikar Dronamraju
2011-09-27 12:59 ` Peter Zijlstra
2011-09-27 12:18 ` Peter Zijlstra
2011-09-27 12:45 ` Srikar Dronamraju
2011-09-27 12:36 ` Peter Zijlstra
2011-09-27 12:37 ` Peter Zijlstra
2011-09-27 12:50 ` Srikar Dronamraju
2011-09-27 12:50 ` Peter Zijlstra
2011-09-27 12:55 ` Peter Zijlstra
2011-10-07 18:37 ` Oleg Nesterov
2011-10-09 11:47 ` Srikar Dronamraju
2011-09-20 12:03 ` [PATCH v5 3.1.0-rc4-tip 19/26] tracing: Extract out common code for kprobes/uprobes traceevents Srikar Dronamraju
2011-09-28 5:04 ` Masami Hiramatsu
2011-09-20 12:04 ` [PATCH v5 3.1.0-rc4-tip 20/26] tracing: uprobes trace_event interface Srikar Dronamraju
2011-09-20 12:04 ` [PATCH v5 3.1.0-rc4-tip 21/26] tracing: uprobes Documentation Srikar Dronamraju
2011-09-20 12:04 ` [PATCH v5 3.1.0-rc4-tip 22/26] perf: rename target_module to target Srikar Dronamraju
2011-09-20 12:04 ` [PATCH v5 3.1.0-rc4-tip 23/26] perf: perf interface for uprobes Srikar Dronamraju
2011-09-20 12:04 ` [PATCH v5 3.1.0-rc4-tip 24/26] perf: show possible probes in a given executable file or library Srikar Dronamraju
2011-09-20 12:05 ` [PATCH v5 3.1.0-rc4-tip 25/26] perf: Documentation for perf uprobes Srikar Dronamraju
2011-09-28 9:20 ` Masami Hiramatsu
2011-09-20 12:05 ` [PATCH v5 3.1.0-rc4-tip 26/26] uprobes: queue signals while thread is singlestepping Srikar Dronamraju
2011-09-27 13:03 ` Peter Zijlstra
2011-09-27 13:12 ` Srikar Dronamraju
2011-10-05 18:01 ` Oleg Nesterov
2011-10-06 5:47 ` Srikar Dronamraju
2011-10-07 16:58 ` Oleg Nesterov
2011-10-10 12:25 ` Srikar Dronamraju
2011-10-10 18:25 ` Oleg Nesterov
2011-10-11 17:24 ` Oleg Nesterov
2011-10-11 17:38 ` Srikar Dronamraju
2011-10-11 17:26 ` Srikar Dronamraju
2011-10-11 18:56 ` Oleg Nesterov
2011-10-12 12:01 ` Srikar Dronamraju
2011-10-12 19:34 ` Oleg Nesterov
2011-10-12 19:59 ` Oleg Nesterov
2011-09-20 13:34 ` [PATCH v5 3.1.0-rc4-tip 0/26] Uprobes patchset with perf probe support Christoph Hellwig
2011-09-20 14:12 ` Srikar Dronamraju
2011-09-20 14:28 ` Christoph Hellwig
2011-09-20 15:19 ` Srikar Dronamraju
2011-10-15 19:00 ` [PATCH 0/X] (Was: Uprobes patchset with perf probe support) Oleg Nesterov
2011-10-15 19:00 ` [PATCH 1/X] uprobes: write_opcode: the new page needs PG_uptodate Oleg Nesterov
2011-10-17 10:59 ` Srikar Dronamraju
2011-10-15 19:00 ` [PATCH 2/X] uprobes: write_opcode() needs put_page(new_page) unconditionally Oleg Nesterov
2011-10-18 16:47 ` Srikar Dronamraju
2011-10-15 19:01 ` [PATCH 3/X] uprobes: xol_add_vma: fix ->uprobes_xol_area initialization Oleg Nesterov
2011-10-15 19:01 ` [PATCH 4/X] uprobes: xol_add_vma: misc cleanups Oleg Nesterov
2011-10-15 19:01 ` [PATCH 5/X] uprobes: xol_alloc_area() needs memory barriers Oleg Nesterov
2011-10-16 16:13 ` [PATCH 6/X] uprobes: reimplement xol_add_vma() via install_special_mapping() Oleg Nesterov
2011-10-17 10:50 ` Srikar Dronamraju
2011-10-17 13:34 ` Stephen Smalley
2011-10-17 18:55 ` Oleg Nesterov
2011-10-16 16:14 ` [PATCH 7/X] uprobes: xol_add_vma: simply use TASK_SIZE as a hint Oleg Nesterov
2011-10-19 21:51 ` [PATCH 8-14/X] (Was: Uprobes patchset with perf probe support) Oleg Nesterov
2011-10-19 21:52 ` [PATCH 8/X] uprobes: kill sstep_complete() Oleg Nesterov
2011-10-19 21:52 ` [PATCH 9/X] uprobes: introduce UTASK_SSTEP_ACK state Oleg Nesterov
2011-10-19 21:52 ` [PATCH 10/X] uprobes: introduce uprobe_deny_signal() Oleg Nesterov
2011-10-19 21:53 ` [PATCH 11/X] uprobes: x86: introduce xol_was_trapped() Oleg Nesterov
2011-10-24 14:55 ` Srikar Dronamraju
2011-10-24 16:07 ` Oleg Nesterov
2011-10-19 21:53 ` [PATCH 12/X] uprobes: x86: introduce abort_xol() Oleg Nesterov
2011-10-21 14:42 ` Srikar Dronamraju
2011-10-21 16:22 ` Oleg Nesterov
2011-10-21 16:26 ` Ananth N Mavinakayanahalli
2011-10-21 16:42 ` Oleg Nesterov
2011-10-21 17:59 ` test-case (Was: [PATCH 12/X] uprobes: x86: introduce abort_xol()) Oleg Nesterov
2011-10-25 14:06 ` Srikar Dronamraju
2011-10-25 15:49 ` Oleg Nesterov
2011-10-22 7:09 ` [PATCH 12/X] uprobes: x86: introduce abort_xol() Ananth N Mavinakayanahalli
2011-10-19 21:53 ` [PATCH 13/X] uprobes: introduce UTASK_SSTEP_TRAPPED logic Oleg Nesterov
2011-10-22 7:20 ` Ananth N Mavinakayanahalli
2011-10-24 14:41 ` Oleg Nesterov
2011-10-24 15:16 ` Ananth N Mavinakayanahalli
2011-10-24 16:13 ` Oleg Nesterov
2011-10-25 6:01 ` Ananth N Mavinakayanahalli
2011-10-25 14:30 ` Oleg Nesterov
2011-10-19 21:54 ` [PATCH 14/X] uprobes: uprobe_deny_signal: check __fatal_signal_pending() Oleg Nesterov
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20110920205317.GA1508@stefanha-thinkpad.localdomain \
--to=stefanha@linux.vnet.ibm.com \
--cc=acme@infradead.org \
--cc=akpm@linux-foundation.org \
--cc=ananth@in.ibm.com \
--cc=andi@firstfloor.org \
--cc=corbet@lwn.net \
--cc=hch@infradead.org \
--cc=hughd@google.com \
--cc=jkenisto@linux.vnet.ibm.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=masami.hiramatsu.pt@hitachi.com \
--cc=mingo@elte.hu \
--cc=oleg@redhat.com \
--cc=peterz@infradead.org \
--cc=roland@hack.frob.com \
--cc=rostedt@goodmis.org \
--cc=srikar@linux.vnet.ibm.com \
--cc=tglx@linutronix.de \
--cc=torvalds@linux-foundation.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).