linux/samples/ftrace
Florent Revest b763e63424 samples: ftrace: Save required argument registers in sample trampolines
commit 8564c31587 upstream.

The ftrace-direct-too sample traces the handle_mm_fault function whose
signature changed since the introduction of the sample. Since:
commit bce617edec ("mm: do page fault accounting in handle_mm_fault")
handle_mm_fault now has 4 arguments. Therefore, the sample trampoline
should save 4 argument registers.

s390 saves all argument registers already so it does not need a change
but x86_64 needs an extra push and pop.

This also evolves the signature of the tracing function to make it
mirror the signature of the traced function.

Link: https://lkml.kernel.org/r/20230427140700.625241-2-revest@chromium.org

Cc: stable@vger.kernel.org
Fixes: bce617edec ("mm: do page fault accounting in handle_mm_fault")
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Florent Revest <revest@chromium.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-07-23 13:47:55 +02:00
..
ftrace-direct-modify.c x86: Prepare inline-asm for straight-line-speculation 2022-05-15 20:18:50 +02:00
ftrace-direct-too.c samples: ftrace: Save required argument registers in sample trampolines 2023-07-23 13:47:55 +02:00
ftrace-direct.c x86: Prepare inline-asm for straight-line-speculation 2022-05-15 20:18:50 +02:00
Makefile tracing: Sample module to demonstrate kernel access to Ftrace instances. 2019-11-22 19:41:08 -05:00
sample-trace-array.c sample-trace-array: Remove trace_array 'sample-instance' 2020-06-16 21:21:02 -04:00
sample-trace-array.h tracing: Sample module to demonstrate kernel access to Ftrace instances. 2019-11-22 19:41:08 -05:00