Re: [Qemu-devel] [PATCH0/6] trace: Per-vCPU tracing states

From: "Lluís Vilanova" <vilanova@ac.upc.edu>
To: qemu-devel@nongnu.org
Cc: Eduardo Habkost <ehabkost@redhat.com>,
	Stefan Hajnoczi <stefanha@redhat.com>
Subject: Re: [Qemu-devel] [PATCH0/6] trace: Per-vCPU tracing states
Date: Mon, 07 Mar 2016 20:35:46 +0100	[thread overview]
Message-ID: <87mvqat71p.fsf@fimbulvetr.bsc.es> (raw)
In-Reply-To: <145641255678.30097.2919142707547689749.stgit@localhost> (=?utf-8?Q?=22Llu=C3=ADs?= Vilanova"'s message of "Thu, 25 Feb 2016 16:02:41 +0100")

There was not much discussion about this before the soft-freeze, but I'm pinging
just in case (feel free to ignore until next window opens).

Thanks,
  Lluis

Lluís Vilanova writes:

> NOTE: This series applies on top of "trace: Show vCPU info in guest code events"

> Provides per-vCPU dynamic controls of the tracing state of events with the
> "vcpu" property.

> A later series proposes an optimization where tracing code can be elided for
> dynamically disabled events (it uses multiple virtual TB caches optimized for
> the current tracing state of the executing vCPU).

> Changes in v1
> =============

> * Rebase on 1b16240.
> * Split from v4 of "trace: Per-vCPU tracing states".
> * Simplify event state initialization.
> * Simplify logic deciding which events are treated by this patch (previously,
>   execution-time events with 'tcg' and 'vcpu' properties; now it's simply events
>   with the 'vcpu' property).
> * Make tracing backends comply with the per-vCPU tracing state.

> Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
> ---

> Lluís Vilanova (6):
>       trace: Identify events with the 'vcpu' property
>       disas: Remove unused macro '_'
>       [trivial] trace: Cosmetic changes on fast-path tracing
>       trace: Add per-vCPU tracing states for events with the 'vcpu' property
>       trace: Conditionally trace events based on their per-vCPU state
>       trace: Add QAPI/QMP interfaces to query and control per-vCPU tracing state

>  Makefile.objs                        |    1 
>  bsd-user/main.c                      |    2 
>  disas/i386.c                         |    2 
>  include/disas/bfd.h                  |    1 
>  include/qom/cpu.h                    |   12 +++
>  linux-user/main.c                    |    2 
>  monitor.c                            |    4 -
>  qapi/trace.json                      |   20 ++++-
>  qmp-commands.hx                      |   18 ++++
>  qom/cpu.c                            |    1 
>  scripts/tracetool/backend/dtrace.py  |    4 -
>  scripts/tracetool/backend/ftrace.py  |   20 ++---
>  scripts/tracetool/backend/log.py     |   26 ++++--
>  scripts/tracetool/backend/simple.py  |   13 ++-
>  scripts/tracetool/backend/ust.py     |    4 -
>  scripts/tracetool/format/events_c.py |   11 ++-
>  scripts/tracetool/format/events_h.py |   12 +++
>  scripts/tracetool/format/h.py        |   18 ++++
>  trace/Makefile.objs                  |   26 ++++++
>  trace/control-internal.h             |   51 ++++++++++--
>  trace/control-stub.c                 |   29 +++++++
>  trace/control-target.c               |   58 ++++++++++++++
>  trace/control.c                      |   25 +++++-
>  trace/control.h                      |   78 ++++++++++++++++++-
>  trace/event-internal.h               |    4 +
>  trace/qmp.c                          |  143 +++++++++++++++++++++++++++-------
>  vl.c                                 |    1 
>  27 files changed, 501 insertions(+), 85 deletions(-)
>  create mode 100644 trace/control-stub.c
>  create mode 100644 trace/control-target.c

> To: qemu-devel@nongnu.org
> Cc: Stefan Hajnoczi <stefanha@redhat.com>
> Cc: Eduardo Habkost <ehabkost@redhat.com>
> Cc: Eric Blake <eblake@redhat.com>