Re: [Qemu-devel] [PATCH v4 00/11] simplify usage of tracepoints, and connect them to logging

["Denis V. Lunev" <den@openvz.org>]

On 01/07/2016 04:55 PM, Denis V. Lunev wrote:
> This series does three things:
>
> 1) add a "-trace [enable=]foo" option to enable one or more trace
> events, and a "-trace help" option to show the list of tracepoints
> (patches 4-5)
>
> 2) change the stderr tracing backend so that it prints to the
> -D log file, and enable it by default.  "-trace file=..." is
> now a synonym of -D if the log backend is enabled (patches 7-8)
>
> 3) add a "-d trace:foo" option that is a synonym for "-trace foo";
> this makes the new functionality more discoverable to people used
> to "-d", makes it available for user-mode emulation (which does
> not have -trace), and is somewhat nice if you want to enable both
> tracepoints and some other "-d" flag (patch 9).  When globbing
> it is also less susceptible to unwanted shell expansion.
>
> For example, you can trace block device I/O and save the result
> to a file just by adding "-trace bdrv_aio_*,file=trace.txt", or
> correlate it to guest PCs with "-d exec,nochain,trace:bdrv_aio_*".
>
> Opinions?  I would like to have this in 2.5 if there is agreement.
>
> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
> Signed-off-by: Denis V. Lunev <den@openvz.org>
>
> Changes from v3:
> - fixed compilation of target-arm/translate-a64.c (patch 7)
> - this warning is not observed in my environment
>        /aarch64/qom/xlnx-ep108:
>      WARNING: RAM size 8000000 is small for EP108OK
> - this warning after patch 10 is seen
>        /microblaze/qom/petalogix-s3adsp1800:
>      Invalid MicroBlaze version number: (null)
>      OK
>    though the problem is here even before any patch of the set. It is
>    just hidden as log is not enabled
> - no problem for Win32 compilation with
>      COLLECT_GCC=x86_64-w64-mingw32-gcc
>      COLLECT_LTO_WRAPPER=/usr/lib/gcc/x86_64-w64-mingw32/4.9-win32/lto-wrapper
>      Target: x86_64-w64-mingw32
>      Configured with: ../../src/configure --build=x86_64-linux-gnu --prefix=/usr --includedir='/usr/include' --mandir='/usr/share/man' --infodir='/usr/share/info' --sysconfdir=/etc --localstatedir=/var --disable-silent-rules --libexecdir='/usr/lib/gcc-mingw-w64' --disable-maintainer-mode --disable-dependency-tracking --prefix=/usr --enable-shared --enable-static --disable-multilib --with-system-zlib --libexecdir=/usr/lib --without-included-gettext --libdir=/usr/lib --enable-libstdcxx-time=yes --with-tune=generic --enable-version-specific-runtime-libs --enable-fully-dynamic-string --enable-libgomp --enable-languages=c,c++,fortran,objc,obj-c++ --enable-lto --with-plugin-ld --enable-threads=win32 --program-suffix=-win32 --program-prefix=x86_64-w64-mingw32- --target=x86_64-w64-mingw32 --with-as=/usr/bin/x86_64-w64-mingw32-as --with-ld=/usr/bin/x86_64-w64-mingw32-ld
>      Thread model: win32
>      gcc version 4.9.2 (GCC)
>
> Changes from v2:
> - compilation fix was extended to patch 2 and 3
> - replaced Reviewed-by with Acked-by by request from Christian
>
> Changes from v1:
> - small cleanup to vl.c is added as patch (4)
> - compilation is fixed in patch (2)
> - moved qemu-log.c to util/log.c to fix linking of qemu-io/qemu-nbd
>
> Denis V. Lunev (2):
>    trace: no need to call trace_backend_init in different branches now
>    log: move qemu-log.c into util/ directory
>
> Paolo Bonzini (9):
>    trace: fix documentation
>    trace: split trace_init_events out of trace_init_backends
>    trace: split trace_init_file out of trace_init_backends
>    trace: add "-trace enable=..."
>    trace: add "-trace help"
>    log: do not unnecessarily include qom/cpu.h
>    trace: convert stderr backend to log
>    trace: switch default backend to "log"
>    log: add "-d trace:PATTERN"
>
>   Makefile.objs                                   |  1 -
>   bsd-user/main.c                                 |  1 +
>   configure                                       |  6 +-
>   cpu-exec.c                                      |  1 +
>   exec.c                                          |  1 +
>   hw/acpi/cpu_hotplug.c                           |  1 +
>   hw/timer/a9gtimer.c                             |  1 +
>   include/exec/log.h                              | 60 ++++++++++++++++
>   include/qemu/log.h                              | 60 +---------------
>   linux-user/main.c                               |  1 +
>   qemu-io.c                                       |  2 +-
>   qemu-options.hx                                 | 22 ++++--
>   qom/cpu.c                                       |  1 +
>   scripts/tracetool/backend/{stderr.py => log.py} |  9 +--
>   target-alpha/translate.c                        |  1 +
>   target-arm/translate-a64.c                      |  1 +
>   target-arm/translate.c                          |  1 +
>   target-cris/translate.c                         |  1 +
>   target-i386/seg_helper.c                        |  1 +
>   target-i386/smm_helper.c                        |  1 +
>   target-i386/translate.c                         |  1 +
>   target-lm32/helper.c                            |  1 +
>   target-lm32/translate.c                         |  1 +
>   target-m68k/translate.c                         |  1 +
>   target-microblaze/helper.c                      |  1 +
>   target-microblaze/translate.c                   |  1 +
>   target-mips/helper.c                            |  1 +
>   target-mips/translate.c                         |  1 +
>   target-moxie/translate.c                        |  1 +
>   target-openrisc/translate.c                     |  1 +
>   target-ppc/mmu-hash32.c                         |  1 +
>   target-ppc/mmu-hash64.c                         |  1 +
>   target-ppc/mmu_helper.c                         |  1 +
>   target-ppc/translate.c                          |  1 +
>   target-s390x/translate.c                        |  1 +
>   target-sh4/helper.c                             |  1 +
>   target-sh4/translate.c                          |  1 +
>   target-sparc/int32_helper.c                     |  1 +
>   target-sparc/int64_helper.c                     |  1 +
>   target-sparc/translate.c                        |  1 +
>   target-tilegx/translate.c                       |  1 +
>   target-tricore/translate.c                      |  1 +
>   target-unicore32/translate.c                    |  1 +
>   target-xtensa/translate.c                       |  1 +
>   tcg/tcg.c                                       |  1 +
>   trace/control.c                                 | 95 ++++++++++++++++++-------
>   trace/control.h                                 | 42 ++++++++++-
>   trace/simple.c                                  |  6 +-
>   trace/simple.h                                  |  4 +-
>   translate-all.c                                 |  1 +
>   util/Makefile.objs                              |  1 +
>   qemu-log.c => util/log.c                        | 19 ++++-
>   vl.c                                            | 38 +++++-----
>   53 files changed, 275 insertions(+), 129 deletions(-)
>   create mode 100644 include/exec/log.h
>   rename scripts/tracetool/backend/{stderr.py => log.py} (78%)
>   rename qemu-log.c => util/log.c (90%)
>
ping