diff options
| author | Florent Revest <revest@chromium.org> | 2023-04-27 16:06:59 +0200 |
|---|---|---|
| committer | Steven Rostedt (Google) <rostedt@goodmis.org> | 2023-07-10 17:50:41 -0400 |
| commit | 8564c315876ab86fcaf8e7f558d6a84cb2ce5590 (patch) | |
| tree | 7d6c788c680d1b841316b896ab60690c0b489cef /samples | |
| parent | 06c2afb862f9da8dc5efa4b6076a0e48c3fbaaa5 (diff) | |
samples: ftrace: Save required argument registers in sample trampolines
The ftrace-direct-too sample traces the handle_mm_fault function whose
signature changed since the introduction of the sample. Since:
commit bce617edecad ("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: bce617edecad ("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>
Diffstat (limited to 'samples')
| -rw-r--r-- | samples/ftrace/ftrace-direct-too.c | 14 |
1 files changed, 8 insertions, 6 deletions
diff --git a/samples/ftrace/ftrace-direct-too.c b/samples/ftrace/ftrace-direct-too.c index a05bc2cc2261..7986033887f6 100644 --- a/samples/ftrace/ftrace-direct-too.c +++ b/samples/ftrace/ftrace-direct-too.c @@ -5,14 +5,14 @@ #include <linux/ftrace.h> #include <asm/asm-offsets.h> -extern void my_direct_func(struct vm_area_struct *vma, - unsigned long address, unsigned int flags); +extern void my_direct_func(struct vm_area_struct *vma, unsigned long address, + unsigned int flags, struct pt_regs *regs); -void my_direct_func(struct vm_area_struct *vma, - unsigned long address, unsigned int flags) +void my_direct_func(struct vm_area_struct *vma, unsigned long address, + unsigned int flags, struct pt_regs *regs) { - trace_printk("handle mm fault vma=%p address=%lx flags=%x\n", - vma, address, flags); + trace_printk("handle mm fault vma=%p address=%lx flags=%x regs=%p\n", + vma, address, flags, regs); } extern void my_tramp(void *); @@ -34,7 +34,9 @@ asm ( " pushq %rdi\n" " pushq %rsi\n" " pushq %rdx\n" +" pushq %rcx\n" " call my_direct_func\n" +" popq %rcx\n" " popq %rdx\n" " popq %rsi\n" " popq %rdi\n" |