From: "Metzger, Markus T" <markus.t.metzger@intel.com>
To: Jan Kratochvil <jan.kratochvil@redhat.com>
Cc: "gdb-patches@sourceware.org" <gdb-patches@sourceware.org>
Subject: RE: [+rfc] Re: [patch v6 00/21] record-btrace: reverse
Date: Fri, 29 Nov 2013 14:27:00 -0000 [thread overview]
Message-ID: <A78C989F6D9628469189715575E55B230AA2E5A9@IRSMSX104.ger.corp.intel.com> (raw)
In-Reply-To: <20131128211623.GA16695@host2.jankratochvil.net>
> -----Original Message-----
> From: Jan Kratochvil [mailto:jan.kratochvil@redhat.com]
> Sent: Thursday, November 28, 2013 10:16 PM
Hello Jan,
> Rather than get_current_frame_nocheck I find safer to just temporarily
> switch
> off the executing flag. There are many other checks which make sense
> which
> were omitted.
>
> Calling set_step_info seems needlessly intrusive to me, there is no need to
> re-set tp->current_symtab + tp->current_line. Despite in the moment of
> record_btrace_start_replaying() I see step_frame_id should be the current
> frame id it does not have to be. Such as when we reverse-continue, it will be
> null_frame_id.
I implemented that based on your patches. It works fine, no regressions.
Thanks for helping make that less hacky.
> I still believe inferior should resume + wait if it changes its PC.
Here I still have problems with multi-threaded inferiors. When I switch to
a different thread and then "record goto", I get a "No more reverse-execution
history" error followed by a "Record goto failed" error.
I believe that "record goto" is resuming the wrong thread after I switch away
from the eventing thread. Curiously, this does not seem to be a problem if
I do not set tp->control.exception_resume_breapoint. This needs some
more debugging.
On a related topic, when we implement "record goto" via resume/wait, we will
trigger breakpoints at the target location. This might or might not be desired.
We do not trigger breakpoints on our way to the record goto target location.
Again, this might or might not be desired.
Record full's "record goto" command does not trigger breakpoints; neither at
the target location nor on its way. In fact, record full does not implement
"record goto" via resume/wait. Instead, it single-steps through its execution
history in a simple do-while loop, similar to what I am doing in record btrace.
Regards,
Markus.
Intel GmbH
Dornacher Strasse 1
85622 Feldkirchen/Muenchen, Deutschland
Sitz der Gesellschaft: Feldkirchen bei Muenchen
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next prev parent reply other threads:[~2013-11-29 14:00 UTC|newest]
Thread overview: 41+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-09-20 11:30 Markus Metzger
2013-09-20 11:30 ` [patch v6 06/21] btrace: increase buffer size Markus Metzger
2013-09-20 11:30 ` [patch v6 02/21] gdbarch: add instruction predicate methods Markus Metzger
2013-09-20 11:30 ` [patch v6 14/21] record-btrace: provide xfer_partial target method Markus Metzger
2013-09-20 11:30 ` [patch v6 15/21] record-btrace: add to_wait and to_resume target methods Markus Metzger
2013-09-20 11:30 ` [patch v6 16/21] record-btrace: provide target_find_new_threads method Markus Metzger
2013-09-20 11:30 ` [patch v6 10/21] target: add ops parameter to to_prepare_to_store method Markus Metzger
2013-09-20 11:30 ` [patch v6 12/21] frame, backtrace: allow targets to supply a frame unwinder Markus Metzger
2013-09-20 11:31 ` [patch v6 08/21] record-btrace: make ranges include begin and end Markus Metzger
2013-09-20 11:31 ` [patch v6 04/21] record-btrace: fix insn range in function call history Markus Metzger
2013-09-20 11:31 ` [patch v6 05/21] record-btrace: start counting at one Markus Metzger
2013-09-20 11:31 ` [patch v6 19/21] btrace, gdbserver: read branch trace incrementally Markus Metzger
2013-10-06 19:51 ` Jan Kratochvil
2013-09-20 11:31 ` [patch v6 13/21] record-btrace, frame: supply target-specific unwinder Markus Metzger
2013-09-20 11:31 ` [patch v6 18/21] record-btrace: extend unwinder Markus Metzger
2013-10-06 19:49 ` Jan Kratochvil
2013-11-06 13:45 ` Metzger, Markus T
2013-11-25 21:11 ` Jan Kratochvil
2013-09-20 11:31 ` [patch v6 03/21] btrace: change branch trace data structure Markus Metzger
2013-10-06 19:46 ` Jan Kratochvil
2013-09-20 11:31 ` [patch v6 01/21] btrace, linux: fix memory leak when reading branch trace Markus Metzger
2013-09-20 11:31 ` [patch v6 07/21] record-btrace: optionally indent function call history Markus Metzger
2013-10-06 19:47 ` Jan Kratochvil
2013-09-20 11:31 ` [patch v6 17/21] record-btrace: add record goto target methods Markus Metzger
2013-10-06 19:48 ` Jan Kratochvil
2013-09-20 11:31 ` [patch v6 09/21] btrace: add replay position to btrace thread info Markus Metzger
2013-09-20 11:31 ` [patch v6 11/21] record-btrace: supply register target methods Markus Metzger
2013-09-20 11:31 ` [patch v6 20/21] record-btrace: show trace from enable location Markus Metzger
2013-09-20 11:31 ` [patch v6 21/21] record-btrace: add (reverse-)stepping support Markus Metzger
2013-10-06 19:52 ` Jan Kratochvil
2013-11-06 15:06 ` Metzger, Markus T
2013-11-26 13:48 ` Jan Kratochvil
2013-09-26 19:16 ` v6 crash bugreport [Re: [patch v6 00/21] record-btrace: reverse] Jan Kratochvil
2013-09-27 6:37 ` Metzger, Markus T
2013-10-06 19:59 ` [+rfc] Re: [patch v6 00/21] record-btrace: reverse Jan Kratochvil
2013-11-07 15:44 ` Metzger, Markus T
2013-11-27 20:35 ` Jan Kratochvil
2013-11-28 10:54 ` Metzger, Markus T
2013-11-28 22:35 ` Jan Kratochvil
2013-11-29 14:27 ` Metzger, Markus T [this message]
2013-12-11 19:57 ` Jan Kratochvil
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