[v5,3/4] arm64: ftrace: Add direct call trampoline samples support
Commit Message
The ftrace samples need per-architecture trampoline implementations
to save and restore argument registers around the calls to
my_direct_func* and to restore polluted registers (eg: x30).
These samples also include <asm/asm-offsets.h> which, on arm64, is not
necessary and redefines previously defined macros (resulting in
warnings) so these includes are guarded by !CONFIG_ARM64.
Signed-off-by: Florent Revest <revest@chromium.org>
---
arch/arm64/Kconfig | 2 ++
samples/ftrace/ftrace-direct-modify.c | 34 ++++++++++++++++++
samples/ftrace/ftrace-direct-multi-modify.c | 38 +++++++++++++++++++++
samples/ftrace/ftrace-direct-multi.c | 23 +++++++++++++
samples/ftrace/ftrace-direct-too.c | 26 ++++++++++++++
samples/ftrace/ftrace-direct.c | 24 +++++++++++++
6 files changed, 147 insertions(+)
Comments
On Mon, Apr 03, 2023 at 01:35:51PM +0200, Florent Revest wrote:
> The ftrace samples need per-architecture trampoline implementations
> to save and restore argument registers around the calls to
> my_direct_func* and to restore polluted registers (eg: x30).
>
> These samples also include <asm/asm-offsets.h> which, on arm64, is not
> necessary and redefines previously defined macros (resulting in
> warnings) so these includes are guarded by !CONFIG_ARM64.
>
> Signed-off-by: Florent Revest <revest@chromium.org>
Overall this looks pretty good!
I spotted a few bugs below while testing, and I've suggested some fixups below.
w.r.t. the asm-offsets include guards. I took a look at fixing arm64's
asm-offsets.c to not be problematic, but it requires some invasive refactoring,
so I'd like to clean that up as a separate series. I don't think that should
block this series, and I think that the include guards are fine for now.
> ---
> arch/arm64/Kconfig | 2 ++
> samples/ftrace/ftrace-direct-modify.c | 34 ++++++++++++++++++
> samples/ftrace/ftrace-direct-multi-modify.c | 38 +++++++++++++++++++++
> samples/ftrace/ftrace-direct-multi.c | 23 +++++++++++++
> samples/ftrace/ftrace-direct-too.c | 26 ++++++++++++++
> samples/ftrace/ftrace-direct.c | 24 +++++++++++++
> 6 files changed, 147 insertions(+)
>
> diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
> index f3503d0cc1b8..c2bf28099abd 100644
> --- a/arch/arm64/Kconfig
> +++ b/arch/arm64/Kconfig
> @@ -194,6 +194,8 @@ config ARM64
> !CC_OPTIMIZE_FOR_SIZE)
> select FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY \
> if DYNAMIC_FTRACE_WITH_ARGS
> + select HAVE_SAMPLE_FTRACE_DIRECT
> + select HAVE_SAMPLE_FTRACE_DIRECT_MULTI
> select HAVE_EFFICIENT_UNALIGNED_ACCESS
> select HAVE_FAST_GUP
> select HAVE_FTRACE_MCOUNT_RECORD
> diff --git a/samples/ftrace/ftrace-direct-modify.c b/samples/ftrace/ftrace-direct-modify.c
> index 25fba66f61c0..98d1b7385f08 100644
> --- a/samples/ftrace/ftrace-direct-modify.c
> +++ b/samples/ftrace/ftrace-direct-modify.c
> @@ -2,7 +2,9 @@
> #include <linux/module.h>
> #include <linux/kthread.h>
> #include <linux/ftrace.h>
> +#ifndef CONFIG_ARM64
> #include <asm/asm-offsets.h>
> +#endif
>
> extern void my_direct_func1(void);
> extern void my_direct_func2(void);
> @@ -96,6 +98,38 @@ asm (
>
> #endif /* CONFIG_S390 */
>
> +#ifdef CONFIG_ARM64
> +
> +asm (
> +" .pushsection .text, \"ax\", @progbits\n"
> +" .type my_tramp1, @function\n"
> +" .globl my_tramp1\n"
> +" my_tramp1:"
> +" bti c\n"
> +" sub sp, sp, #16\n"
> +" stp x9, x30, [sp]\n"
> +" bl my_direct_func1\n"
> +" ldp x30, x9, [sp]\n"
> +" add sp, sp, #16\n"
> +" ret x9\n"
> +" .size my_tramp1, .-my_tramp1\n"
> +
> +" .type my_tramp2, @function\n"
> +" .globl my_tramp2\n"
> +" my_tramp2:"
> +" bti c\n"
> +" sub sp, sp, #16\n"
> +" stp x9, x30, [sp]\n"
> +" bl my_direct_func2\n"
> +" ldp x30, x9, [sp]\n"
> +" add sp, sp, #16\n"
> +" ret x9\n"
> +" .size my_tramp2, .-my_tramp2\n"
> +" .popsection\n"
> +);
> +
> +#endif /* CONFIG_ARM64 */
These looks functionally correct, given they'll only be attached to schedule()
and the direct funcs take no arguments, so there's no arguments to save/restore
and nothing to shuffle.
As an aside, I believe we'll need to rework the sequences when we add support
for RELIABLE_STACKTRACE so that the unwinder can reliably acquire the address
of the instrumented function and its caller, but I think for now it's
preferable to keep this simple and I'm happy to make that a problem for future
me.
> diff --git a/samples/ftrace/ftrace-direct-multi-modify.c b/samples/ftrace/ftrace-direct-multi-modify.c
> index f72623899602..e39108eb085d 100644
> --- a/samples/ftrace/ftrace-direct-multi-modify.c
> +++ b/samples/ftrace/ftrace-direct-multi-modify.c
> @@ -2,7 +2,9 @@
> #include <linux/module.h>
> #include <linux/kthread.h>
> #include <linux/ftrace.h>
> +#ifndef CONFIG_ARM64
> #include <asm/asm-offsets.h>
> +#endif
>
> extern void my_direct_func1(unsigned long ip);
> extern void my_direct_func2(unsigned long ip);
> @@ -103,6 +105,42 @@ asm (
>
> #endif /* CONFIG_S390 */
>
> +#ifdef CONFIG_ARM64
> +
> +asm (
> +" .pushsection .text, \"ax\", @progbits\n"
> +" .type my_tramp1, @function\n"
> +" .globl my_tramp1\n"
> +" my_tramp1:"
> +" bti c\n"
> +" sub sp, sp, #32\n"
> +" stp x9, x30, [sp]\n"
> +" str x0, [sp, #16]\n"
> +" bl my_direct_func1\n"
> +" ldp x30, x9, [sp]\n"
> +" ldr x0, [sp, #16]\n"
> +" add sp, sp, #32\n"
> +" ret x9\n"
> +" .size my_tramp1, .-my_tramp1\n"
> +
> +" .type my_tramp2, @function\n"
> +" .globl my_tramp2\n"
> +" my_tramp2:"
> +" bti c\n"
> +" sub sp, sp, #32\n"
> +" stp x9, x30, [sp]\n"
> +" str x0, [sp, #16]\n"
> +" bl my_direct_func2\n"
> +" ldp x30, x9, [sp]\n"
> +" ldr x0, [sp, #16]\n"
> +" add sp, sp, #32\n"
> +" ret x9\n"
> +" .size my_tramp2, .-my_tramp2\n"
> +" .popsection\n"
> +);
> +
> +#endif /* CONFIG_ARM64 */
For both of these trampolines we need to pass the trampoline's return address
(i.e. where we'll return to in the instrumented function) as the 'ip' argument
to my_direct_func{1,2}().
In both cases, just before the 'bl my_direct_func{1,2}' we'll need to add:
mov x0, x30
[...]
> diff --git a/samples/ftrace/ftrace-direct-multi.c b/samples/ftrace/ftrace-direct-multi.c
> index 1547c2c6be02..5a395d2d2e07 100644
> --- a/samples/ftrace/ftrace-direct-multi.c
> +++ b/samples/ftrace/ftrace-direct-multi.c
> @@ -4,7 +4,9 @@
> #include <linux/mm.h> /* for handle_mm_fault() */
> #include <linux/ftrace.h>
> #include <linux/sched/stat.h>
> +#ifndef CONFIG_ARM64
> #include <asm/asm-offsets.h>
> +#endif
>
> extern void my_direct_func(unsigned long ip);
>
> @@ -66,6 +68,27 @@ asm (
>
> #endif /* CONFIG_S390 */
>
> +#ifdef CONFIG_ARM64
> +
> +asm (
> +" .pushsection .text, \"ax\", @progbits\n"
> +" .type my_tramp, @function\n"
> +" .globl my_tramp\n"
> +" my_tramp:"
> +" bti c\n"
> +" sub sp, sp, #32\n"
> +" stp x9, x30, [sp]\n"
> +" str x0, [sp, #16]\n"
> +" bl my_direct_func\n"
> +" ldp x30, x9, [sp]\n"
> +" ldr x0, [sp, #16]\n"
> +" add sp, sp, #32\n"
> +" ret x9\n"
> +" .size my_tramp, .-my_tramp\n"
> +" .popsection\n"
> +);
> +
> +#endif /* CONFIG_ARM64 */
> static struct ftrace_ops direct;
As with ftrace-direct-multi-modify.c, we need to pass the return address of the
trampoline as the 'ip' argument to my_direct_func1(), so just before the 'bl
my_direct_func' we'll need to add:
mov x0, x30
[...]
> diff --git a/samples/ftrace/ftrace-direct-too.c b/samples/ftrace/ftrace-direct-too.c
> index f28e7b99840f..6e93c45fea86 100644
> --- a/samples/ftrace/ftrace-direct-too.c
> +++ b/samples/ftrace/ftrace-direct-too.c
> @@ -3,7 +3,9 @@
>
> #include <linux/mm.h> /* for handle_mm_fault() */
> #include <linux/ftrace.h>
> +#ifndef CONFIG_ARM64
> #include <asm/asm-offsets.h>
> +#endif
>
> extern void my_direct_func(struct vm_area_struct *vma,
> unsigned long address, unsigned int flags);
This gets attached to handle_mm_fault(), whose prototype is currently:
vm_fault_t handle_mm_fault(struct vm_area_struct *vma, unsigned long address,
unsigned int flags, struct pt_regs *regs)
i.e. it has 4 arguments, in x0 to x3.
> @@ -70,6 +72,30 @@ asm (
>
> #endif /* CONFIG_S390 */
>
> +#ifdef CONFIG_ARM64
> +
> +asm (
> +" .pushsection .text, \"ax\", @progbits\n"
> +" .type my_tramp, @function\n"
> +" .globl my_tramp\n"
> +" my_tramp:"
> +" bti c\n"
> +" sub sp, sp, #48\n"
> +" stp x9, x30, [sp]\n"
> +" stp x0, x1, [sp, #16]\n"
> +" str x2, [sp, #32]\n"
> +" bl my_direct_func\n"
> +" ldp x30, x9, [sp]\n"
> +" ldp x0, x1, [sp, #16]\n"
> +" ldr x2, [sp, #32]\n"
So here we need to save+restore x3 also.
We already have the space reserved, so that should just be a matter of using
stp/ldp for x2 and x3.
> +" add sp, sp, #48\n"
> +" ret x9\n"
> +" .size my_tramp, .-my_tramp\n"
> +" .popsection\n"
> +);
> +
> +#endif /* CONFIG_ARM64 */
> +
> static struct ftrace_ops direct;
>
> static int __init ftrace_direct_init(void)
> diff --git a/samples/ftrace/ftrace-direct.c b/samples/ftrace/ftrace-direct.c
> index d81a9473b585..e5312f9c15d3 100644
> --- a/samples/ftrace/ftrace-direct.c
> +++ b/samples/ftrace/ftrace-direct.c
> @@ -3,7 +3,9 @@
>
> #include <linux/sched.h> /* for wake_up_process() */
> #include <linux/ftrace.h>
> +#ifndef CONFIG_ARM64
> #include <asm/asm-offsets.h>
> +#endif
>
> extern void my_direct_func(struct task_struct *p);
>
> @@ -63,6 +65,28 @@ asm (
>
> #endif /* CONFIG_S390 */
>
> +#ifdef CONFIG_ARM64
> +
> +asm (
> +" .pushsection .text, \"ax\", @progbits\n"
> +" .type my_tramp, @function\n"
> +" .globl my_tramp\n"
> +" my_tramp:"
> +" bti c\n"
> +" sub sp, sp, #32\n"
> +" stp x9, x30, [sp]\n"
> +" str x0, [sp, #16]\n"
> +" bl my_direct_func\n"
> +" ldp x30, x9, [sp]\n"
> +" ldr x0, [sp, #16]\n"
> +" add sp, sp, #32\n"
> +" ret x9\n"
> +" .size my_tramp, .-my_tramp\n"
> +" .popsection\n"
> +);
This looks fine. Since my_direct_func() is attached to wake_up_process() and
expects its single argument, saving/restoring x0 is sufficient and we don't
need any additional register shuffling.
Thanks,
Mark.
On Mon, Apr 3, 2023 at 7:26 PM Mark Rutland <mark.rutland@arm.com> wrote:
>
> On Mon, Apr 03, 2023 at 01:35:51PM +0200, Florent Revest wrote:
> > The ftrace samples need per-architecture trampoline implementations
> > to save and restore argument registers around the calls to
> > my_direct_func* and to restore polluted registers (eg: x30).
> >
> > These samples also include <asm/asm-offsets.h> which, on arm64, is not
> > necessary and redefines previously defined macros (resulting in
> > warnings) so these includes are guarded by !CONFIG_ARM64.
> >
> > Signed-off-by: Florent Revest <revest@chromium.org>
>
> Overall this looks pretty good!
>
> I spotted a few bugs below while testing, and I've suggested some fixups below.
>
> w.r.t. the asm-offsets include guards. I took a look at fixing arm64's
> asm-offsets.c to not be problematic, but it requires some invasive refactoring,
> so I'd like to clean that up as a separate series. I don't think that should
> block this series, and I think that the include guards are fine for now.
Sounds great! Thank you Mark :)
> > ---
> > arch/arm64/Kconfig | 2 ++
> > samples/ftrace/ftrace-direct-modify.c | 34 ++++++++++++++++++
> > samples/ftrace/ftrace-direct-multi-modify.c | 38 +++++++++++++++++++++
> > samples/ftrace/ftrace-direct-multi.c | 23 +++++++++++++
> > samples/ftrace/ftrace-direct-too.c | 26 ++++++++++++++
> > samples/ftrace/ftrace-direct.c | 24 +++++++++++++
> > 6 files changed, 147 insertions(+)
> >
> > diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
> > index f3503d0cc1b8..c2bf28099abd 100644
> > --- a/arch/arm64/Kconfig
> > +++ b/arch/arm64/Kconfig
> > @@ -194,6 +194,8 @@ config ARM64
> > !CC_OPTIMIZE_FOR_SIZE)
> > select FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY \
> > if DYNAMIC_FTRACE_WITH_ARGS
> > + select HAVE_SAMPLE_FTRACE_DIRECT
> > + select HAVE_SAMPLE_FTRACE_DIRECT_MULTI
> > select HAVE_EFFICIENT_UNALIGNED_ACCESS
> > select HAVE_FAST_GUP
> > select HAVE_FTRACE_MCOUNT_RECORD
> > diff --git a/samples/ftrace/ftrace-direct-modify.c b/samples/ftrace/ftrace-direct-modify.c
> > index 25fba66f61c0..98d1b7385f08 100644
> > --- a/samples/ftrace/ftrace-direct-modify.c
> > +++ b/samples/ftrace/ftrace-direct-modify.c
> > @@ -2,7 +2,9 @@
> > #include <linux/module.h>
> > #include <linux/kthread.h>
> > #include <linux/ftrace.h>
> > +#ifndef CONFIG_ARM64
> > #include <asm/asm-offsets.h>
> > +#endif
> >
> > extern void my_direct_func1(void);
> > extern void my_direct_func2(void);
> > @@ -96,6 +98,38 @@ asm (
> >
> > #endif /* CONFIG_S390 */
> >
> > +#ifdef CONFIG_ARM64
> > +
> > +asm (
> > +" .pushsection .text, \"ax\", @progbits\n"
> > +" .type my_tramp1, @function\n"
> > +" .globl my_tramp1\n"
> > +" my_tramp1:"
> > +" bti c\n"
> > +" sub sp, sp, #16\n"
> > +" stp x9, x30, [sp]\n"
> > +" bl my_direct_func1\n"
> > +" ldp x30, x9, [sp]\n"
> > +" add sp, sp, #16\n"
> > +" ret x9\n"
> > +" .size my_tramp1, .-my_tramp1\n"
> > +
> > +" .type my_tramp2, @function\n"
> > +" .globl my_tramp2\n"
> > +" my_tramp2:"
> > +" bti c\n"
> > +" sub sp, sp, #16\n"
> > +" stp x9, x30, [sp]\n"
> > +" bl my_direct_func2\n"
> > +" ldp x30, x9, [sp]\n"
> > +" add sp, sp, #16\n"
> > +" ret x9\n"
> > +" .size my_tramp2, .-my_tramp2\n"
> > +" .popsection\n"
> > +);
> > +
> > +#endif /* CONFIG_ARM64 */
>
> These looks functionally correct, given they'll only be attached to schedule()
> and the direct funcs take no arguments, so there's no arguments to save/restore
> and nothing to shuffle.
>
> As an aside, I believe we'll need to rework the sequences when we add support
> for RELIABLE_STACKTRACE so that the unwinder can reliably acquire the address
> of the instrumented function and its caller, but I think for now it's
> preferable to keep this simple and I'm happy to make that a problem for future
> me.
Ah, interesting. I'd be happy to help when that time comes! :)
> > diff --git a/samples/ftrace/ftrace-direct-multi-modify.c b/samples/ftrace/ftrace-direct-multi-modify.c
> > index f72623899602..e39108eb085d 100644
> > --- a/samples/ftrace/ftrace-direct-multi-modify.c
> > +++ b/samples/ftrace/ftrace-direct-multi-modify.c
> > @@ -2,7 +2,9 @@
> > #include <linux/module.h>
> > #include <linux/kthread.h>
> > #include <linux/ftrace.h>
> > +#ifndef CONFIG_ARM64
> > #include <asm/asm-offsets.h>
> > +#endif
> >
> > extern void my_direct_func1(unsigned long ip);
> > extern void my_direct_func2(unsigned long ip);
> > @@ -103,6 +105,42 @@ asm (
> >
> > #endif /* CONFIG_S390 */
> >
> > +#ifdef CONFIG_ARM64
> > +
> > +asm (
> > +" .pushsection .text, \"ax\", @progbits\n"
> > +" .type my_tramp1, @function\n"
> > +" .globl my_tramp1\n"
> > +" my_tramp1:"
> > +" bti c\n"
> > +" sub sp, sp, #32\n"
> > +" stp x9, x30, [sp]\n"
> > +" str x0, [sp, #16]\n"
> > +" bl my_direct_func1\n"
> > +" ldp x30, x9, [sp]\n"
> > +" ldr x0, [sp, #16]\n"
> > +" add sp, sp, #32\n"
> > +" ret x9\n"
> > +" .size my_tramp1, .-my_tramp1\n"
> > +
> > +" .type my_tramp2, @function\n"
> > +" .globl my_tramp2\n"
> > +" my_tramp2:"
> > +" bti c\n"
> > +" sub sp, sp, #32\n"
> > +" stp x9, x30, [sp]\n"
> > +" str x0, [sp, #16]\n"
> > +" bl my_direct_func2\n"
> > +" ldp x30, x9, [sp]\n"
> > +" ldr x0, [sp, #16]\n"
> > +" add sp, sp, #32\n"
> > +" ret x9\n"
> > +" .size my_tramp2, .-my_tramp2\n"
> > +" .popsection\n"
> > +);
> > +
> > +#endif /* CONFIG_ARM64 */
>
> For both of these trampolines we need to pass the trampoline's return address
> (i.e. where we'll return to in the instrumented function) as the 'ip' argument
> to my_direct_func{1,2}().
>
> In both cases, just before the 'bl my_direct_func{1,2}' we'll need to add:
>
> mov x0, x30
Oopsie, yes! Very good catch!
> > diff --git a/samples/ftrace/ftrace-direct-multi.c b/samples/ftrace/ftrace-direct-multi.c
> > index 1547c2c6be02..5a395d2d2e07 100644
> > --- a/samples/ftrace/ftrace-direct-multi.c
> > +++ b/samples/ftrace/ftrace-direct-multi.c
> > @@ -4,7 +4,9 @@
> > #include <linux/mm.h> /* for handle_mm_fault() */
> > #include <linux/ftrace.h>
> > #include <linux/sched/stat.h>
> > +#ifndef CONFIG_ARM64
> > #include <asm/asm-offsets.h>
> > +#endif
> >
> > extern void my_direct_func(unsigned long ip);
> >
> > @@ -66,6 +68,27 @@ asm (
> >
> > #endif /* CONFIG_S390 */
> >
> > +#ifdef CONFIG_ARM64
> > +
> > +asm (
> > +" .pushsection .text, \"ax\", @progbits\n"
> > +" .type my_tramp, @function\n"
> > +" .globl my_tramp\n"
> > +" my_tramp:"
> > +" bti c\n"
> > +" sub sp, sp, #32\n"
> > +" stp x9, x30, [sp]\n"
> > +" str x0, [sp, #16]\n"
> > +" bl my_direct_func\n"
> > +" ldp x30, x9, [sp]\n"
> > +" ldr x0, [sp, #16]\n"
> > +" add sp, sp, #32\n"
> > +" ret x9\n"
> > +" .size my_tramp, .-my_tramp\n"
> > +" .popsection\n"
> > +);
> > +
> > +#endif /* CONFIG_ARM64 */
> > static struct ftrace_ops direct;
>
> As with ftrace-direct-multi-modify.c, we need to pass the return address of the
> trampoline as the 'ip' argument to my_direct_func1(), so just before the 'bl
> my_direct_func' we'll need to add:
>
> mov x0, x30
Will do :)
> > diff --git a/samples/ftrace/ftrace-direct-too.c b/samples/ftrace/ftrace-direct-too.c
> > index f28e7b99840f..6e93c45fea86 100644
> > --- a/samples/ftrace/ftrace-direct-too.c
> > +++ b/samples/ftrace/ftrace-direct-too.c
> > @@ -3,7 +3,9 @@
> >
> > #include <linux/mm.h> /* for handle_mm_fault() */
> > #include <linux/ftrace.h>
> > +#ifndef CONFIG_ARM64
> > #include <asm/asm-offsets.h>
> > +#endif
> >
> > extern void my_direct_func(struct vm_area_struct *vma,
> > unsigned long address, unsigned int flags);
>
> This gets attached to handle_mm_fault(), whose prototype is currently:
>
> vm_fault_t handle_mm_fault(struct vm_area_struct *vma, unsigned long address,
> unsigned int flags, struct pt_regs *regs)
>
> i.e. it has 4 arguments, in x0 to x3.
>
> > @@ -70,6 +72,30 @@ asm (
> >
> > #endif /* CONFIG_S390 */
> >
> > +#ifdef CONFIG_ARM64
> > +
> > +asm (
> > +" .pushsection .text, \"ax\", @progbits\n"
> > +" .type my_tramp, @function\n"
> > +" .globl my_tramp\n"
> > +" my_tramp:"
> > +" bti c\n"
> > +" sub sp, sp, #48\n"
> > +" stp x9, x30, [sp]\n"
> > +" stp x0, x1, [sp, #16]\n"
> > +" str x2, [sp, #32]\n"
> > +" bl my_direct_func\n"
> > +" ldp x30, x9, [sp]\n"
> > +" ldp x0, x1, [sp, #16]\n"
> > +" ldr x2, [sp, #32]\n"
>
> So here we need to save+restore x3 also.
>
> We already have the space reserved, so that should just be a matter of using
> stp/ldp for x2 and x3.
That's also a very good catch. It looks like it's an issue for the
sample trampoline on x86_64 as well, I'll fix it too in a separate
patch as part of v6. (if i understand s390 asm correctly, the stmg
already saves all arg registers in one instruction so s390 doesn't
need to change)
@@ -194,6 +194,8 @@ config ARM64
!CC_OPTIMIZE_FOR_SIZE)
select FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY \
if DYNAMIC_FTRACE_WITH_ARGS
+ select HAVE_SAMPLE_FTRACE_DIRECT
+ select HAVE_SAMPLE_FTRACE_DIRECT_MULTI
select HAVE_EFFICIENT_UNALIGNED_ACCESS
select HAVE_FAST_GUP
select HAVE_FTRACE_MCOUNT_RECORD
@@ -2,7 +2,9 @@
#include <linux/module.h>
#include <linux/kthread.h>
#include <linux/ftrace.h>
+#ifndef CONFIG_ARM64
#include <asm/asm-offsets.h>
+#endif
extern void my_direct_func1(void);
extern void my_direct_func2(void);
@@ -96,6 +98,38 @@ asm (
#endif /* CONFIG_S390 */
+#ifdef CONFIG_ARM64
+
+asm (
+" .pushsection .text, \"ax\", @progbits\n"
+" .type my_tramp1, @function\n"
+" .globl my_tramp1\n"
+" my_tramp1:"
+" bti c\n"
+" sub sp, sp, #16\n"
+" stp x9, x30, [sp]\n"
+" bl my_direct_func1\n"
+" ldp x30, x9, [sp]\n"
+" add sp, sp, #16\n"
+" ret x9\n"
+" .size my_tramp1, .-my_tramp1\n"
+
+" .type my_tramp2, @function\n"
+" .globl my_tramp2\n"
+" my_tramp2:"
+" bti c\n"
+" sub sp, sp, #16\n"
+" stp x9, x30, [sp]\n"
+" bl my_direct_func2\n"
+" ldp x30, x9, [sp]\n"
+" add sp, sp, #16\n"
+" ret x9\n"
+" .size my_tramp2, .-my_tramp2\n"
+" .popsection\n"
+);
+
+#endif /* CONFIG_ARM64 */
+
static struct ftrace_ops direct;
static unsigned long my_tramp = (unsigned long)my_tramp1;
@@ -2,7 +2,9 @@
#include <linux/module.h>
#include <linux/kthread.h>
#include <linux/ftrace.h>
+#ifndef CONFIG_ARM64
#include <asm/asm-offsets.h>
+#endif
extern void my_direct_func1(unsigned long ip);
extern void my_direct_func2(unsigned long ip);
@@ -103,6 +105,42 @@ asm (
#endif /* CONFIG_S390 */
+#ifdef CONFIG_ARM64
+
+asm (
+" .pushsection .text, \"ax\", @progbits\n"
+" .type my_tramp1, @function\n"
+" .globl my_tramp1\n"
+" my_tramp1:"
+" bti c\n"
+" sub sp, sp, #32\n"
+" stp x9, x30, [sp]\n"
+" str x0, [sp, #16]\n"
+" bl my_direct_func1\n"
+" ldp x30, x9, [sp]\n"
+" ldr x0, [sp, #16]\n"
+" add sp, sp, #32\n"
+" ret x9\n"
+" .size my_tramp1, .-my_tramp1\n"
+
+" .type my_tramp2, @function\n"
+" .globl my_tramp2\n"
+" my_tramp2:"
+" bti c\n"
+" sub sp, sp, #32\n"
+" stp x9, x30, [sp]\n"
+" str x0, [sp, #16]\n"
+" bl my_direct_func2\n"
+" ldp x30, x9, [sp]\n"
+" ldr x0, [sp, #16]\n"
+" add sp, sp, #32\n"
+" ret x9\n"
+" .size my_tramp2, .-my_tramp2\n"
+" .popsection\n"
+);
+
+#endif /* CONFIG_ARM64 */
+
static unsigned long my_tramp = (unsigned long)my_tramp1;
static unsigned long tramps[2] = {
(unsigned long)my_tramp1,
@@ -4,7 +4,9 @@
#include <linux/mm.h> /* for handle_mm_fault() */
#include <linux/ftrace.h>
#include <linux/sched/stat.h>
+#ifndef CONFIG_ARM64
#include <asm/asm-offsets.h>
+#endif
extern void my_direct_func(unsigned long ip);
@@ -66,6 +68,27 @@ asm (
#endif /* CONFIG_S390 */
+#ifdef CONFIG_ARM64
+
+asm (
+" .pushsection .text, \"ax\", @progbits\n"
+" .type my_tramp, @function\n"
+" .globl my_tramp\n"
+" my_tramp:"
+" bti c\n"
+" sub sp, sp, #32\n"
+" stp x9, x30, [sp]\n"
+" str x0, [sp, #16]\n"
+" bl my_direct_func\n"
+" ldp x30, x9, [sp]\n"
+" ldr x0, [sp, #16]\n"
+" add sp, sp, #32\n"
+" ret x9\n"
+" .size my_tramp, .-my_tramp\n"
+" .popsection\n"
+);
+
+#endif /* CONFIG_ARM64 */
static struct ftrace_ops direct;
static int __init ftrace_direct_multi_init(void)
@@ -3,7 +3,9 @@
#include <linux/mm.h> /* for handle_mm_fault() */
#include <linux/ftrace.h>
+#ifndef CONFIG_ARM64
#include <asm/asm-offsets.h>
+#endif
extern void my_direct_func(struct vm_area_struct *vma,
unsigned long address, unsigned int flags);
@@ -70,6 +72,30 @@ asm (
#endif /* CONFIG_S390 */
+#ifdef CONFIG_ARM64
+
+asm (
+" .pushsection .text, \"ax\", @progbits\n"
+" .type my_tramp, @function\n"
+" .globl my_tramp\n"
+" my_tramp:"
+" bti c\n"
+" sub sp, sp, #48\n"
+" stp x9, x30, [sp]\n"
+" stp x0, x1, [sp, #16]\n"
+" str x2, [sp, #32]\n"
+" bl my_direct_func\n"
+" ldp x30, x9, [sp]\n"
+" ldp x0, x1, [sp, #16]\n"
+" ldr x2, [sp, #32]\n"
+" add sp, sp, #48\n"
+" ret x9\n"
+" .size my_tramp, .-my_tramp\n"
+" .popsection\n"
+);
+
+#endif /* CONFIG_ARM64 */
+
static struct ftrace_ops direct;
static int __init ftrace_direct_init(void)
@@ -3,7 +3,9 @@
#include <linux/sched.h> /* for wake_up_process() */
#include <linux/ftrace.h>
+#ifndef CONFIG_ARM64
#include <asm/asm-offsets.h>
+#endif
extern void my_direct_func(struct task_struct *p);
@@ -63,6 +65,28 @@ asm (
#endif /* CONFIG_S390 */
+#ifdef CONFIG_ARM64
+
+asm (
+" .pushsection .text, \"ax\", @progbits\n"
+" .type my_tramp, @function\n"
+" .globl my_tramp\n"
+" my_tramp:"
+" bti c\n"
+" sub sp, sp, #32\n"
+" stp x9, x30, [sp]\n"
+" str x0, [sp, #16]\n"
+" bl my_direct_func\n"
+" ldp x30, x9, [sp]\n"
+" ldr x0, [sp, #16]\n"
+" add sp, sp, #32\n"
+" ret x9\n"
+" .size my_tramp, .-my_tramp\n"
+" .popsection\n"
+);
+
+#endif /* CONFIG_ARM64 */
+
static struct ftrace_ops direct;
static int __init ftrace_direct_init(void)