tracing/treewide: Remove second parameter of __assign_str()

With the rework of how the __string() handles dynamic strings where it
saves off the source string in field in the helper structure[1], th

tracing/treewide: Remove second parameter of __assign_str()

With the rework of how the __string() handles dynamic strings where it
saves off the source string in field in the helper structure[1], the
assignment of that value to the trace event field is stored in the helper
value and does not need to be passed in again.

This means that with:

__string(field, mystring)

Which use to be assigned with __assign_str(field, mystring), no longer
needs the second parameter and it is unused. With this, __assign_str()
will now only get a single parameter.

There's over 700 users of __assign_str() and because coccinelle does not
handle the TRACE_EVENT() macro I ended up using the following sed script:

git grep -l __assign_str | while read a ; do
sed -e 's/\(__assign_str([^,]*[^ ,]\) *,[^;]*/\1)/' $a > /tmp/test-file;
mv /tmp/test-file $a;
done

I then searched for __assign_str() that did not end with ';' as those
were multi line assignments that the sed script above would fail to catch.

Note, the same updates will need to be done for:

__assign_str_len()
__assign_rel_str()
__assign_rel_str_len()

I tested this with both an allmodconfig and an allyesconfig (build only for both).

[1] https://lore.kernel.org/linux-trace-kernel/[email protected]/

Link: https://lore.kernel.org/linux-trace-kernel/[email protected]

Cc: Masami Hiramatsu <[email protected]>
Cc: Mathieu Desnoyers <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Julia Lawall <[email protected]>
Signed-off-by: Steven Rostedt (Google) <[email protected]>
Acked-by: Jani Nikula <[email protected]>
Acked-by: Christian König <[email protected]> for the amdgpu parts.
Acked-by: Thomas Hellström <[email protected]> #for
Acked-by: Rafael J. Wysocki <[email protected]> # for thermal
Acked-by: Takashi Iwai <[email protected]>
Acked-by: Darrick J. Wong <[email protected]> # xfs
Tested-by: Guenter Roeck <[email protected]>

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tracing: initcall: Ordered comparison of function pointers

Using initcall_t in the __field macro generates the following warning
with clang version 6.0:

include/trace/events/initcall.h:34:3: warnin

tracing: initcall: Ordered comparison of function pointers

Using initcall_t in the __field macro generates the following warning
with clang version 6.0:

include/trace/events/initcall.h:34:3: warning: ordered comparison of
function pointers ('initcall_t' (aka 'int (*)(void)') and 'initcall_t')

__field macro expands to __field_ext macro which does is_signed_type
check on the type argument. Since initcall_t is defined as a function
pointer, using it as the type in the __field macro, leads to an ordered
comparison of function pointer warning, inside the check. Using
__field_struct macro avoids the issue.

Link: http://lkml.kernel.org/r/[email protected]

Signed-off-by: Rishabh Bhatnagar <[email protected]>
[ Added comment to why we are using field_struct() ]
Signed-off-by: Steven Rostedt (VMware) <[email protected]>

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init, tracing: Add initcall trace events

Being able to trace the start and stop of initcalls is useful to see where
the timings are an issue. There is already an "initcall_debug" parameter,
but that

init, tracing: Add initcall trace events

Being able to trace the start and stop of initcalls is useful to see where
the timings are an issue. There is already an "initcall_debug" parameter,
but that can cause a large overhead itself, as the printing of the
information may take longer than the initcall functions.

Adding in a start and finish trace event around the initcall functions, as
well as a trace event that records the level of the initcalls, one can get a
much finer measurement of the times and interactions of the initcalls
themselves, as trace events are much lighter than printk()s.

Suggested-by: Abderrahmane Benbachir <[email protected]>
Signed-off-by: Steven Rostedt (VMware) <[email protected]>

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