| Message ID | 20111208224807.21668.94467.stgit@ginnungagap.bsc.es |
|---|---|
| State | New |
| Headers | show |
This series must be updated to apply on top of the patch recently accepted by Stefan into the tracing tree [1]. [1] http://lists.gnu.org/archive/html/qemu-devel/2011-12/msg00763.html Lluis Lluís Vilanova writes: > Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu> > --- > docs/tracing.txt | 22 ++++++++++++++++------ > 1 files changed, 16 insertions(+), 6 deletions(-) > diff --git a/docs/tracing.txt b/docs/tracing.txt > index ea29f2c..853cbf8 100644 > --- a/docs/tracing.txt > +++ b/docs/tracing.txt > @@ -98,12 +98,6 @@ respectively. This ensures portability between 32- and 64-bit platforms. > 4. Name trace events after their function. If there are multiple trace events > in one function, append a unique distinguisher at the end of the name. > -5. If specific trace events are going to be called a huge number of times, this > - might have a noticeable performance impact even when the trace events are > - programmatically disabled. In this case you should declare the trace event > - with the "disable" property, which will effectively disable it at compile > - time (using the "nop" backend). > - > == Generic interface and monitor commands == > You can programmatically query and control the dynamic state of trace events > @@ -234,3 +228,19 @@ probes: > --target-type system \ > --target-arch x86_64 \ > <trace-events >qemu.stp > + > +== Trace event properties == > + > +Each event in the "trace-events" file can be prefixed with a space-separated > +list of zero or more of the following event properties. > + > +=== "disable" === > + > +If a specific trace event is going to be invoked a huge number of times, this > +might have a noticeable performance impact even when the event is > +programmatically disabled. > + > +In this case you should declare such event with the "disable" property. This > +will effectively disable the event at compile time (by using the "nop" backend), > +thus having no performance impact at all on regular builds (i.e., unless you > +edit the "trace-events" file).
diff --git a/docs/tracing.txt b/docs/tracing.txt index ea29f2c..853cbf8 100644 --- a/docs/tracing.txt +++ b/docs/tracing.txt @@ -98,12 +98,6 @@ respectively. This ensures portability between 32- and 64-bit platforms. 4. Name trace events after their function. If there are multiple trace events in one function, append a unique distinguisher at the end of the name. -5. If specific trace events are going to be called a huge number of times, this - might have a noticeable performance impact even when the trace events are - programmatically disabled. In this case you should declare the trace event - with the "disable" property, which will effectively disable it at compile - time (using the "nop" backend). - == Generic interface and monitor commands == You can programmatically query and control the dynamic state of trace events @@ -234,3 +228,19 @@ probes: --target-type system \ --target-arch x86_64 \ <trace-events >qemu.stp + +== Trace event properties == + +Each event in the "trace-events" file can be prefixed with a space-separated +list of zero or more of the following event properties. + +=== "disable" === + +If a specific trace event is going to be invoked a huge number of times, this +might have a noticeable performance impact even when the event is +programmatically disabled. + +In this case you should declare such event with the "disable" property. This +will effectively disable the event at compile time (by using the "nop" backend), +thus having no performance impact at all on regular builds (i.e., unless you +edit the "trace-events" file).
Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu> --- docs/tracing.txt | 22 ++++++++++++++++------ 1 files changed, 16 insertions(+), 6 deletions(-)