[PULL 0/2] Tracing patches

[PULL 0/2] Tracing patches

[Stefan Hajnoczi]

The following changes since commit 8f3f329f5e0117bd1a23a79ab751f8a7d3471e4b:

  Merge tag 'migration-20240311-pull-request' of https://gitlab.com/peterx/qemu into staging (2024-03-12 11:35:41 +0000)

are available in the Git repository at:

  https://gitlab.com/stefanha/qemu.git tags/tracing-pull-request

for you to fetch changes up to 2b608e16ca00017509fa2a211b7b49aacdedb760:

  meson: generate .stp files for tools too (2024-03-12 14:52:07 -0400)

----------------------------------------------------------------
Pull request

----------------------------------------------------------------

Daniel P. Berrangé (2):
  tracetool: remove redundant --target-type / --target-name args
  meson: generate .stp files for tools too

 docs/devel/tracing.rst |  3 +-
 meson.build            | 63 +++++++++++++++++++++++++++---------------
 scripts/tracetool.py   | 24 ++++------------
 3 files changed, 46 insertions(+), 44 deletions(-)

-- 
2.44.0

[PULL 1/2] tracetool: remove redundant --target-type / --target-name args

[Stefan Hajnoczi]

From: Daniel P. Berrangé <berrange@redhat.com>

The --target-type and --target-name args are used to construct
the default probe prefix if '--probe-prefix' is not given. The
meson.build will always pass '--probe-prefix', so the other args
are effectively redundant.

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Message-id: 20240108171356.1037059-2-berrange@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 docs/devel/tracing.rst |  3 +--
 meson.build            |  2 --
 scripts/tracetool.py   | 24 +++++-------------------
 3 files changed, 6 insertions(+), 23 deletions(-)

diff --git a/docs/devel/tracing.rst b/docs/devel/tracing.rst
index d288480db1..043bed7fd0 100644
--- a/docs/devel/tracing.rst
+++ b/docs/devel/tracing.rst
@@ -357,8 +357,7 @@ probes::
 
     scripts/tracetool.py --backends=dtrace --format=stap \
                          --binary path/to/qemu-binary \
-                         --target-type system \
-                         --target-name x86_64 \
+                         --probe-prefix qemu.system.x86_64 \
                          --group=all \
                          trace-events-all \
                          qemu.stp
diff --git a/meson.build b/meson.build
index f9dbe7634e..b8d40d7c0a 100644
--- a/meson.build
+++ b/meson.build
@@ -3991,8 +3991,6 @@ foreach target : target_dirs
                       command: [
                         tracetool, '--group=all', '--format=' + stp['fmt'],
                         '--binary=' + stp['bin'],
-                        '--target-name=' + target_name,
-                        '--target-type=' + target_type,
                         '--probe-prefix=qemu.' + target_type + '.' + target_name,
                         '@INPUT@', '@OUTPUT@'
                       ],
diff --git a/scripts/tracetool.py b/scripts/tracetool.py
index ab7653a5ce..5de9ce96d3 100755
--- a/scripts/tracetool.py
+++ b/scripts/tracetool.py
@@ -44,12 +44,9 @@ def error_opt(msg = None):
     --help                   This help message.
     --list-backends          Print list of available backends.
     --check-backends         Check if the given backend is valid.
-    --binary <path>          Full path to QEMU binary.
-    --target-type <type>     QEMU emulator target type ('system' or 'user').
-    --target-name <name>     QEMU emulator target name.
-    --group <name>           Name of the event group
-    --probe-prefix <prefix>  Prefix for dtrace probe names
-                             (default: qemu-<target-type>-<target-name>).\
+    --binary <path>          Full path to QEMU binary (required for 'stap' backend).
+    --group <name>           Name of the event group.
+    --probe-prefix <prefix>  Prefix for dtrace probe names (required for 'stap' backend).
 """ % {
             "script" : _SCRIPT,
             "backends" : backend_descr,
@@ -67,7 +64,7 @@ def main(args):
 
     long_opts = ["backends=", "format=", "help", "list-backends",
                  "check-backends", "group="]
-    long_opts += ["binary=", "target-type=", "target-name=", "probe-prefix="]
+    long_opts += ["binary=", "probe-prefix="]
 
     try:
         opts, args = getopt.getopt(args[1:], "", long_opts)
@@ -79,8 +76,6 @@ def main(args):
     arg_format = ""
     arg_group = None
     binary = None
-    target_type = None
-    target_name = None
     probe_prefix = None
     for opt, arg in opts:
         if opt == "--help":
@@ -102,10 +97,6 @@ def main(args):
 
         elif opt == "--binary":
             binary = arg
-        elif opt == '--target-type':
-            target_type = arg
-        elif opt == '--target-name':
-            target_name = arg
         elif opt == '--probe-prefix':
             probe_prefix = arg
 
@@ -127,13 +118,8 @@ def main(args):
     if arg_format == "stap":
         if binary is None:
             error_opt("--binary is required for SystemTAP tapset generator")
-        if probe_prefix is None and target_type is None:
-            error_opt("--target-type is required for SystemTAP tapset generator")
-        if probe_prefix is None and target_name is None:
-            error_opt("--target-name is required for SystemTAP tapset generator")
-
         if probe_prefix is None:
-            probe_prefix = ".".join(["qemu", target_type, target_name])
+            error_opt("--probe-prefix is required for SystemTAP tapset generator")
 
     if len(args) < 2:
         error_opt("missing trace-events and output filepaths")
-- 
2.44.0

[PULL 2/2] meson: generate .stp files for tools too

[Stefan Hajnoczi]

From: Daniel P. Berrangé <berrange@redhat.com>

The qemu-img, qemu-io, qemu-nbd, qemu-storage-daemon tools all have
support for systemtap tracing built-in, so should be given corresponding
.stp files to define their probes.

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20240108171356.1037059-3-berrange@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 meson.build | 61 +++++++++++++++++++++++++++++++++++------------------
 1 file changed, 40 insertions(+), 21 deletions(-)

diff --git a/meson.build b/meson.build
index b8d40d7c0a..520f862d7b 100644
--- a/meson.build
+++ b/meson.build
@@ -3808,6 +3808,7 @@ if host_os == 'darwin'
   entitlement = find_program('scripts/entitlement.sh')
 endif
 
+traceable = []
 emulators = {}
 foreach target : target_dirs
   config_target = config_target_mak[target]
@@ -3976,27 +3977,11 @@ foreach target : target_dirs
       emulators += {exe['name']: emulator}
     endif
 
-    if stap.found()
-      foreach stp: [
-        {'ext': '.stp-build', 'fmt': 'stap', 'bin': meson.current_build_dir() / exe['name'], 'install': false},
-        {'ext': '.stp', 'fmt': 'stap', 'bin': get_option('prefix') / get_option('bindir') / exe['name'], 'install': true},
-        {'ext': '-simpletrace.stp', 'fmt': 'simpletrace-stap', 'bin': '', 'install': true},
-        {'ext': '-log.stp', 'fmt': 'log-stap', 'bin': '', 'install': true},
-      ]
-        custom_target(exe['name'] + stp['ext'],
-                      input: trace_events_all,
-                      output: exe['name'] + stp['ext'],
-                      install: stp['install'],
-                      install_dir: get_option('datadir') / 'systemtap/tapset',
-                      command: [
-                        tracetool, '--group=all', '--format=' + stp['fmt'],
-                        '--binary=' + stp['bin'],
-                        '--probe-prefix=qemu.' + target_type + '.' + target_name,
-                        '@INPUT@', '@OUTPUT@'
-                      ],
-                      depend_files: tracetool_depends)
-      endforeach
-    endif
+    traceable += [{
+      'exe': exe['name'],
+      'probe-prefix': 'qemu.' + target_type + '.' + target_name,
+    }]
+
   endforeach
 endforeach
 
@@ -4031,6 +4016,14 @@ if have_tools
                install: true)
 
   subdir('storage-daemon')
+
+  foreach exe: [ 'qemu-img', 'qemu-io', 'qemu-nbd', 'qemu-storage-daemon']
+    traceable += [{
+      'exe': exe,
+      'probe-prefix': 'qemu.' + exe.substring(5).replace('-', '_')
+    }]
+  endforeach
+
   subdir('contrib/rdmacm-mux')
   subdir('contrib/elf2dmp')
 
@@ -4063,6 +4056,32 @@ if have_tools
   endif
 endif
 
+if stap.found()
+  foreach t: traceable
+    foreach stp: [
+      {'ext': '.stp-build', 'fmt': 'stap', 'bin': meson.current_build_dir() / t['exe'], 'install': false},
+      {'ext': '.stp', 'fmt': 'stap', 'bin': get_option('prefix') / get_option('bindir') / t['exe'], 'install': true},
+      {'ext': '-simpletrace.stp', 'fmt': 'simpletrace-stap', 'bin': '', 'install': true},
+      {'ext': '-log.stp', 'fmt': 'log-stap', 'bin': '', 'install': true},
+    ]
+      cmd = [
+        tracetool, '--group=all', '--format=' + stp['fmt'],
+        '--binary=' + stp['bin'],
+        '--probe-prefix=' + t['probe-prefix'],
+        '@INPUT@', '@OUTPUT@'
+      ]
+
+      custom_target(t['exe'] + stp['ext'],
+                    input: trace_events_all,
+                    output: t['exe'] + stp['ext'],
+                    install: stp['install'],
+                    install_dir: get_option('datadir') / 'systemtap/tapset',
+                    command: cmd,
+                    depend_files: tracetool_depends)
+    endforeach
+  endforeach
+endif
+
 subdir('scripts')
 subdir('tools')
 subdir('pc-bios')
-- 
2.44.0

Re: [PULL 0/2] Tracing patches

[Peter Maydell]

On Tue, 12 Mar 2024 at 19:04, Stefan Hajnoczi <stefanha@redhat.com> wrote:
>
> The following changes since commit 8f3f329f5e0117bd1a23a79ab751f8a7d3471e4b:
>
>   Merge tag 'migration-20240311-pull-request' of https://gitlab.com/peterx/qemu into staging (2024-03-12 11:35:41 +0000)
>
> are available in the Git repository at:
>
>   https://gitlab.com/stefanha/qemu.git tags/tracing-pull-request
>
> for you to fetch changes up to 2b608e16ca00017509fa2a211b7b49aacdedb760:
>
>   meson: generate .stp files for tools too (2024-03-12 14:52:07 -0400)
>
> ----------------------------------------------------------------
> Pull request
>


Applied, thanks.

Please update the changelog at https://wiki.qemu.org/ChangeLog/9.0
for any user-visible changes.

-- PMM