5efe9688f9
The pid filtering test will set the pid filters and make sure that both
function and function_graph tracing honors the filters. But the
function_graph tracer test was failing because the PID was not being
filtered properly. That's because the funcgraph-proc option wasn't getting
set. Without that option the PID is not shown.
Instead we get:
+ cat trace
# tracer: function_graph
#
# CPU DURATION FUNCTION CALLS
# | | | | | | |
3) ! 143.685 us | kernel_clone();
3) ! 127.055 us | kernel_clone();
1) ! 127.170 us | kernel_clone();
3) ! 126.840 us | kernel_clone();
When we should be getting:
+ cat trace
# tracer: function_graph
#
# CPU TASK/PID DURATION FUNCTION CALLS
# | | | | | | | | |
4) bash-939 | # 1070.009 us | kernel_clone();
4) bash-939 | # 1116.903 us | kernel_clone();
5) bash-939 | ! 976.133 us | kernel_clone();
5) bash-939 | ! 954.012 us | kernel_clone();
The test looks for the pids it is filtering and will fail if it can not
find them. Without fungraph-proc option set, it will not be displayed and
the test will fail.
Link: https://lore.kernel.org/all/Zl9JFnzKGuUM10X2@J2N7QTR9R3/
Link: https://lore.kernel.org/linux-trace-kernel/20240604152550.0c01d7cd@gandalf.local.home
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Fixes: 35b944a997 ("selftests/ftrace: Add function_graph tracer to func-filter-pid test")
Reported-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the reStructuredText markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.