* Re: [PATCH v14 03/19] function_graph: Pass ftrace_regs to entryfunc
[not found] ` <172615372005.133222.15797801841635819220.stgit@devnote2>
@ 2024-09-15 8:56 ` Steven Rostedt
0 siblings, 0 replies; 3+ messages in thread
From: Steven Rostedt @ 2024-09-15 8:56 UTC (permalink / raw)
To: Paul Walmsley, Palmer Dabbelt, Albert Ou, linux-riscv
Cc: Masami Hiramatsu (Google), Florent Revest, linux-trace-kernel,
LKML, Alexei Starovoitov, Jiri Olsa, Arnaldo Carvalho de Melo,
Daniel Borkmann, Alan Maguire, Mark Rutland
Can I get an Acked-by from the RISC-V maintainers for this patch?
Thanks!
-- Steve
On Fri, 13 Sep 2024 00:08:40 +0900
"Masami Hiramatsu (Google)" <mhiramat@kernel.org> wrote:
> From: Masami Hiramatsu (Google) <mhiramat@kernel.org>
>
> Pass ftrace_regs to the fgraph_ops::entryfunc(). If ftrace_regs is not
> available, it passes a NULL instead. User callback function can access
> some registers (including return address) via this ftrace_regs.
>
> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
> ---
> Changes in v11:
> - Update for the latest for-next branch.
> Changes in v8:
> - Just pass ftrace_regs to the handler instead of adding a new
> entryregfunc.
> - Update riscv ftrace_graph_func().
> Changes in v3:
> - Update for new multiple fgraph.
> ---
> arch/arm64/kernel/ftrace.c | 20 +++++++++++-
> arch/loongarch/kernel/ftrace_dyn.c | 10 +++++-
> arch/powerpc/kernel/trace/ftrace.c | 2 +
> arch/powerpc/kernel/trace/ftrace_64_pg.c | 10 ++++--
> arch/riscv/kernel/ftrace.c | 17 ++++++++++
> arch/x86/kernel/ftrace.c | 50 +++++++++++++++++++++---------
> include/linux/ftrace.h | 18 ++++++++---
> kernel/trace/fgraph.c | 23 ++++++++------
> kernel/trace/ftrace.c | 3 +-
> kernel/trace/trace.h | 3 +-
> kernel/trace/trace_functions_graph.c | 3 +-
> kernel/trace/trace_irqsoff.c | 3 +-
> kernel/trace/trace_sched_wakeup.c | 3 +-
> kernel/trace/trace_selftest.c | 8 +++--
> 14 files changed, 128 insertions(+), 45 deletions(-)
>
> diff --git a/arch/arm64/kernel/ftrace.c b/arch/arm64/kernel/ftrace.c
> index a650f5e11fc5..bc647b725e6a 100644
> --- a/arch/arm64/kernel/ftrace.c
> +++ b/arch/arm64/kernel/ftrace.c
> @@ -481,7 +481,25 @@ void prepare_ftrace_return(unsigned long self_addr, unsigned long *parent,
> void ftrace_graph_func(unsigned long ip, unsigned long parent_ip,
> struct ftrace_ops *op, struct ftrace_regs *fregs)
> {
> - prepare_ftrace_return(ip, &fregs->lr, fregs->fp);
> + unsigned long return_hooker = (unsigned long)&return_to_handler;
> + unsigned long frame_pointer = fregs->fp;
> + unsigned long *parent = &fregs->lr;
> + unsigned long old;
> +
> + if (unlikely(atomic_read(¤t->tracing_graph_pause)))
> + return;
> +
> + /*
> + * Note:
> + * No protection against faulting at *parent, which may be seen
> + * on other archs. It's unlikely on AArch64.
> + */
> + old = *parent;
> +
> + if (!function_graph_enter_regs(old, ip, frame_pointer,
> + (void *)frame_pointer, fregs)) {
> + *parent = return_hooker;
> + }
> }
> #else
> /*
> diff --git a/arch/loongarch/kernel/ftrace_dyn.c b/arch/loongarch/kernel/ftrace_dyn.c
> index bff058317062..966e0f7f7aca 100644
> --- a/arch/loongarch/kernel/ftrace_dyn.c
> +++ b/arch/loongarch/kernel/ftrace_dyn.c
> @@ -243,8 +243,16 @@ void ftrace_graph_func(unsigned long ip, unsigned long parent_ip,
> {
> struct pt_regs *regs = &fregs->regs;
> unsigned long *parent = (unsigned long *)®s->regs[1];
> + unsigned long return_hooker = (unsigned long)&return_to_handler;
> + unsigned long old;
> +
> + if (unlikely(atomic_read(¤t->tracing_graph_pause)))
> + return;
> +
> + old = *parent;
>
> - prepare_ftrace_return(ip, (unsigned long *)parent);
> + if (!function_graph_enter_regs(old, ip, 0, parent, fregs))
> + *parent = return_hooker;
> }
> #else
> static int ftrace_modify_graph_caller(bool enable)
> diff --git a/arch/powerpc/kernel/trace/ftrace.c b/arch/powerpc/kernel/trace/ftrace.c
> index d8d6b4fd9a14..a1a0e0b57662 100644
> --- a/arch/powerpc/kernel/trace/ftrace.c
> +++ b/arch/powerpc/kernel/trace/ftrace.c
> @@ -434,7 +434,7 @@ void ftrace_graph_func(unsigned long ip, unsigned long parent_ip,
> if (bit < 0)
> goto out;
>
> - if (!function_graph_enter(parent_ip, ip, 0, (unsigned long *)sp))
> + if (!function_graph_enter_regs(parent_ip, ip, 0, (unsigned long *)sp, fregs))
> parent_ip = ppc_function_entry(return_to_handler);
>
> ftrace_test_recursion_unlock(bit);
> diff --git a/arch/powerpc/kernel/trace/ftrace_64_pg.c b/arch/powerpc/kernel/trace/ftrace_64_pg.c
> index 12fab1803bcf..4ae9eeb1c8f1 100644
> --- a/arch/powerpc/kernel/trace/ftrace_64_pg.c
> +++ b/arch/powerpc/kernel/trace/ftrace_64_pg.c
> @@ -800,7 +800,8 @@ int ftrace_disable_ftrace_graph_caller(void)
> * in current thread info. Return the address we want to divert to.
> */
> static unsigned long
> -__prepare_ftrace_return(unsigned long parent, unsigned long ip, unsigned long sp)
> +__prepare_ftrace_return(unsigned long parent, unsigned long ip, unsigned long sp,
> + struct ftrace_regs *fregs)
> {
> unsigned long return_hooker;
> int bit;
> @@ -817,7 +818,7 @@ __prepare_ftrace_return(unsigned long parent, unsigned long ip, unsigned long sp
>
> return_hooker = ppc_function_entry(return_to_handler);
>
> - if (!function_graph_enter(parent, ip, 0, (unsigned long *)sp))
> + if (!function_graph_enter_regs(parent, ip, 0, (unsigned long *)sp, fregs))
> parent = return_hooker;
>
> ftrace_test_recursion_unlock(bit);
> @@ -829,13 +830,14 @@ __prepare_ftrace_return(unsigned long parent, unsigned long ip, unsigned long sp
> void ftrace_graph_func(unsigned long ip, unsigned long parent_ip,
> struct ftrace_ops *op, struct ftrace_regs *fregs)
> {
> - fregs->regs.link = __prepare_ftrace_return(parent_ip, ip, fregs->regs.gpr[1]);
> + fregs->regs.link = __prepare_ftrace_return(parent_ip, ip,
> + fregs->regs.gpr[1], fregs);
> }
> #else
> unsigned long prepare_ftrace_return(unsigned long parent, unsigned long ip,
> unsigned long sp)
> {
> - return __prepare_ftrace_return(parent, ip, sp);
> + return __prepare_ftrace_return(parent, ip, sp, NULL);
> }
> #endif
> #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
> diff --git a/arch/riscv/kernel/ftrace.c b/arch/riscv/kernel/ftrace.c
> index 4b95c574fd04..f5c3b5a752b0 100644
> --- a/arch/riscv/kernel/ftrace.c
> +++ b/arch/riscv/kernel/ftrace.c
> @@ -214,7 +214,22 @@ void prepare_ftrace_return(unsigned long *parent, unsigned long self_addr,
> void ftrace_graph_func(unsigned long ip, unsigned long parent_ip,
> struct ftrace_ops *op, struct ftrace_regs *fregs)
> {
> - prepare_ftrace_return(&fregs->ra, ip, fregs->s0);
> + unsigned long return_hooker = (unsigned long)&return_to_handler;
> + unsigned long frame_pointer = fregs->s0;
> + unsigned long *parent = &fregs->ra;
> + unsigned long old;
> +
> + if (unlikely(atomic_read(¤t->tracing_graph_pause)))
> + return;
> +
> + /*
> + * We don't suffer access faults, so no extra fault-recovery assembly
> + * is needed here.
> + */
> + old = *parent;
> +
> + if (!function_graph_enter_regs(old, ip, frame_pointer, parent, fregs))
> + *parent = return_hooker;
> }
> #else /* CONFIG_DYNAMIC_FTRACE_WITH_ARGS */
> extern void ftrace_graph_call(void);
> diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c
> index 8da0e66ca22d..decf4c11dcf3 100644
> --- a/arch/x86/kernel/ftrace.c
> +++ b/arch/x86/kernel/ftrace.c
> @@ -605,16 +605,8 @@ int ftrace_disable_ftrace_graph_caller(void)
> }
> #endif /* CONFIG_DYNAMIC_FTRACE && !CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS */
>
> -/*
> - * Hook the return address and push it in the stack of return addrs
> - * in current thread info.
> - */
> -void prepare_ftrace_return(unsigned long ip, unsigned long *parent,
> - unsigned long frame_pointer)
> +static inline bool skip_ftrace_return(void)
> {
> - unsigned long return_hooker = (unsigned long)&return_to_handler;
> - int bit;
> -
> /*
> * When resuming from suspend-to-ram, this function can be indirectly
> * called from early CPU startup code while the CPU is in real mode,
> @@ -624,13 +616,28 @@ void prepare_ftrace_return(unsigned long ip, unsigned long *parent,
> * This check isn't as accurate as virt_addr_valid(), but it should be
> * good enough for this purpose, and it's fast.
> */
> - if (unlikely((long)__builtin_frame_address(0) >= 0))
> - return;
> + if ((long)__builtin_frame_address(0) >= 0)
> + return true;
>
> - if (unlikely(ftrace_graph_is_dead()))
> - return;
> + if (ftrace_graph_is_dead())
> + return true;
> +
> + if (atomic_read(¤t->tracing_graph_pause))
> + return true;
> + return false;
> +}
> +
> +/*
> + * Hook the return address and push it in the stack of return addrs
> + * in current thread info.
> + */
> +void prepare_ftrace_return(unsigned long ip, unsigned long *parent,
> + unsigned long frame_pointer)
> +{
> + unsigned long return_hooker = (unsigned long)&return_to_handler;
> + int bit;
>
> - if (unlikely(atomic_read(¤t->tracing_graph_pause)))
> + if (unlikely(skip_ftrace_return()))
> return;
>
> bit = ftrace_test_recursion_trylock(ip, *parent);
> @@ -649,8 +656,21 @@ void ftrace_graph_func(unsigned long ip, unsigned long parent_ip,
> {
> struct pt_regs *regs = &fregs->regs;
> unsigned long *stack = (unsigned long *)kernel_stack_pointer(regs);
> + unsigned long return_hooker = (unsigned long)&return_to_handler;
> + unsigned long *parent = (unsigned long *)stack;
> + int bit;
>
> - prepare_ftrace_return(ip, (unsigned long *)stack, 0);
> + if (unlikely(skip_ftrace_return()))
> + return;
> +
> + bit = ftrace_test_recursion_trylock(ip, *parent);
> + if (bit < 0)
> + return;
> +
> + if (!function_graph_enter_regs(*parent, ip, 0, parent, fregs))
> + *parent = return_hooker;
> +
> + ftrace_test_recursion_unlock(bit);
> }
> #endif
>
> diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h
> index f84fb9635fb0..1fe49a28de2d 100644
> --- a/include/linux/ftrace.h
> +++ b/include/linux/ftrace.h
> @@ -1063,9 +1063,12 @@ struct fgraph_ops;
> typedef void (*trace_func_graph_ret_t)(struct ftrace_graph_ret *,
> struct fgraph_ops *); /* return */
> typedef int (*trace_func_graph_ent_t)(struct ftrace_graph_ent *,
> - struct fgraph_ops *); /* entry */
> + struct fgraph_ops *,
> + struct ftrace_regs *); /* entry */
>
> -extern int ftrace_graph_entry_stub(struct ftrace_graph_ent *trace, struct fgraph_ops *gops);
> +extern int ftrace_graph_entry_stub(struct ftrace_graph_ent *trace,
> + struct fgraph_ops *gops,
> + struct ftrace_regs *fregs);
> bool ftrace_pids_enabled(struct ftrace_ops *ops);
>
> #ifdef CONFIG_FUNCTION_GRAPH_TRACER
> @@ -1108,8 +1111,15 @@ struct ftrace_ret_stack {
> extern void return_to_handler(void);
>
> extern int
> -function_graph_enter(unsigned long ret, unsigned long func,
> - unsigned long frame_pointer, unsigned long *retp);
> +function_graph_enter_regs(unsigned long ret, unsigned long func,
> + unsigned long frame_pointer, unsigned long *retp,
> + struct ftrace_regs *fregs);
> +
> +static inline int function_graph_enter(unsigned long ret, unsigned long func,
> + unsigned long fp, unsigned long *retp)
> +{
> + return function_graph_enter_regs(ret, func, fp, retp, NULL);
> +}
>
> struct ftrace_ret_stack *
> ftrace_graph_get_ret_stack(struct task_struct *task, int skip);
> diff --git a/kernel/trace/fgraph.c b/kernel/trace/fgraph.c
> index d7d4fb403f6f..0322c5723748 100644
> --- a/kernel/trace/fgraph.c
> +++ b/kernel/trace/fgraph.c
> @@ -290,7 +290,8 @@ static inline unsigned long make_data_type_val(int idx, int size, int offset)
> }
>
> /* ftrace_graph_entry set to this to tell some archs to run function graph */
> -static int entry_run(struct ftrace_graph_ent *trace, struct fgraph_ops *ops)
> +static int entry_run(struct ftrace_graph_ent *trace, struct fgraph_ops *ops,
> + struct ftrace_regs *fregs)
> {
> return 0;
> }
> @@ -484,7 +485,7 @@ int __weak ftrace_disable_ftrace_graph_caller(void)
> #endif
>
> int ftrace_graph_entry_stub(struct ftrace_graph_ent *trace,
> - struct fgraph_ops *gops)
> + struct fgraph_ops *gops, struct ftrace_regs *fregs)
> {
> return 0;
> }
> @@ -612,8 +613,9 @@ ftrace_push_return_trace(unsigned long ret, unsigned long func,
> #endif
>
> /* If the caller does not use ftrace, call this function. */
> -int function_graph_enter(unsigned long ret, unsigned long func,
> - unsigned long frame_pointer, unsigned long *retp)
> +int function_graph_enter_regs(unsigned long ret, unsigned long func,
> + unsigned long frame_pointer, unsigned long *retp,
> + struct ftrace_regs *fregs)
> {
> struct ftrace_graph_ent trace;
> unsigned long bitmap = 0;
> @@ -631,7 +633,7 @@ int function_graph_enter(unsigned long ret, unsigned long func,
> if (static_branch_likely(&fgraph_do_direct)) {
> int save_curr_ret_stack = current->curr_ret_stack;
>
> - if (static_call(fgraph_func)(&trace, fgraph_direct_gops))
> + if (static_call(fgraph_func)(&trace, fgraph_direct_gops, fregs))
> bitmap |= BIT(fgraph_direct_gops->idx);
> else
> /* Clear out any saved storage */
> @@ -649,7 +651,7 @@ int function_graph_enter(unsigned long ret, unsigned long func,
>
> save_curr_ret_stack = current->curr_ret_stack;
> if (ftrace_ops_test(&gops->ops, func, NULL) &&
> - gops->entryfunc(&trace, gops))
> + gops->entryfunc(&trace, gops, fregs))
> bitmap |= BIT(i);
> else
> /* Clear out any saved storage */
> @@ -925,7 +927,7 @@ unsigned long ftrace_graph_ret_addr(struct task_struct *task, int *idx,
>
> static struct ftrace_ops graph_ops = {
> .func = ftrace_graph_func,
> - .flags = FTRACE_OPS_GRAPH_STUB,
> + .flags = FTRACE_OPS_GRAPH_STUB | FTRACE_OPS_FL_SAVE_ARGS,
> #ifdef FTRACE_GRAPH_TRAMP_ADDR
> .trampoline = FTRACE_GRAPH_TRAMP_ADDR,
> /* trampoline_size is only needed for dynamically allocated tramps */
> @@ -935,7 +937,8 @@ static struct ftrace_ops graph_ops = {
> void fgraph_init_ops(struct ftrace_ops *dst_ops,
> struct ftrace_ops *src_ops)
> {
> - dst_ops->flags = FTRACE_OPS_FL_PID | FTRACE_OPS_GRAPH_STUB;
> + dst_ops->flags = FTRACE_OPS_FL_PID | FTRACE_OPS_GRAPH_STUB |
> + FTRACE_OPS_FL_SAVE_ARGS;
>
> #ifdef CONFIG_DYNAMIC_FTRACE
> if (src_ops) {
> @@ -1119,7 +1122,7 @@ void ftrace_graph_exit_task(struct task_struct *t)
>
> #ifdef CONFIG_DYNAMIC_FTRACE
> static int fgraph_pid_func(struct ftrace_graph_ent *trace,
> - struct fgraph_ops *gops)
> + struct fgraph_ops *gops, struct ftrace_regs *fregs)
> {
> struct trace_array *tr = gops->ops.private;
> int pid;
> @@ -1133,7 +1136,7 @@ static int fgraph_pid_func(struct ftrace_graph_ent *trace,
> return 0;
> }
>
> - return gops->saved_func(trace, gops);
> + return gops->saved_func(trace, gops, fregs);
> }
>
> void fgraph_update_pid_func(void)
> diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
> index 4c28dd177ca6..775040a9f541 100644
> --- a/kernel/trace/ftrace.c
> +++ b/kernel/trace/ftrace.c
> @@ -821,7 +821,8 @@ void ftrace_graph_graph_time_control(bool enable)
> }
>
> static int profile_graph_entry(struct ftrace_graph_ent *trace,
> - struct fgraph_ops *gops)
> + struct fgraph_ops *gops,
> + struct ftrace_regs *fregs)
> {
> struct ftrace_ret_stack *ret_stack;
>
> diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
> index bd3e3069300e..28d8ad5e31e6 100644
> --- a/kernel/trace/trace.h
> +++ b/kernel/trace/trace.h
> @@ -683,7 +683,8 @@ void trace_default_header(struct seq_file *m);
> void print_trace_header(struct seq_file *m, struct trace_iterator *iter);
>
> void trace_graph_return(struct ftrace_graph_ret *trace, struct fgraph_ops *gops);
> -int trace_graph_entry(struct ftrace_graph_ent *trace, struct fgraph_ops *gops);
> +int trace_graph_entry(struct ftrace_graph_ent *trace, struct fgraph_ops *gops,
> + struct ftrace_regs *fregs);
>
> void tracing_start_cmdline_record(void);
> void tracing_stop_cmdline_record(void);
> diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c
> index 13d0387ac6a6..b9785fc919c9 100644
> --- a/kernel/trace/trace_functions_graph.c
> +++ b/kernel/trace/trace_functions_graph.c
> @@ -128,7 +128,8 @@ static inline int ftrace_graph_ignore_irqs(void)
> }
>
> int trace_graph_entry(struct ftrace_graph_ent *trace,
> - struct fgraph_ops *gops)
> + struct fgraph_ops *gops,
> + struct ftrace_regs *fregs)
> {
> unsigned long *task_var = fgraph_get_task_var(gops);
> struct trace_array *tr = gops->private;
> diff --git a/kernel/trace/trace_irqsoff.c b/kernel/trace/trace_irqsoff.c
> index fce064e20570..ad739d76fc86 100644
> --- a/kernel/trace/trace_irqsoff.c
> +++ b/kernel/trace/trace_irqsoff.c
> @@ -176,7 +176,8 @@ static int irqsoff_display_graph(struct trace_array *tr, int set)
> }
>
> static int irqsoff_graph_entry(struct ftrace_graph_ent *trace,
> - struct fgraph_ops *gops)
> + struct fgraph_ops *gops,
> + struct ftrace_regs *fregs)
> {
> struct trace_array *tr = irqsoff_trace;
> struct trace_array_cpu *data;
> diff --git a/kernel/trace/trace_sched_wakeup.c b/kernel/trace/trace_sched_wakeup.c
> index 130ca7e7787e..23360a2700de 100644
> --- a/kernel/trace/trace_sched_wakeup.c
> +++ b/kernel/trace/trace_sched_wakeup.c
> @@ -113,7 +113,8 @@ static int wakeup_display_graph(struct trace_array *tr, int set)
> }
>
> static int wakeup_graph_entry(struct ftrace_graph_ent *trace,
> - struct fgraph_ops *gops)
> + struct fgraph_ops *gops,
> + struct ftrace_regs *fregs)
> {
> struct trace_array *tr = wakeup_trace;
> struct trace_array_cpu *data;
> diff --git a/kernel/trace/trace_selftest.c b/kernel/trace/trace_selftest.c
> index c4ad7cd7e778..89067f02094a 100644
> --- a/kernel/trace/trace_selftest.c
> +++ b/kernel/trace/trace_selftest.c
> @@ -773,7 +773,8 @@ struct fgraph_fixture {
> };
>
> static __init int store_entry(struct ftrace_graph_ent *trace,
> - struct fgraph_ops *gops)
> + struct fgraph_ops *gops,
> + struct ftrace_regs *fregs)
> {
> struct fgraph_fixture *fixture = container_of(gops, struct fgraph_fixture, gops);
> const char *type = fixture->store_type_name;
> @@ -1024,7 +1025,8 @@ static unsigned int graph_hang_thresh;
>
> /* Wrap the real function entry probe to avoid possible hanging */
> static int trace_graph_entry_watchdog(struct ftrace_graph_ent *trace,
> - struct fgraph_ops *gops)
> + struct fgraph_ops *gops,
> + struct ftrace_regs *fregs)
> {
> /* This is harmlessly racy, we want to approximately detect a hang */
> if (unlikely(++graph_hang_thresh > GRAPH_MAX_FUNC_TEST)) {
> @@ -1038,7 +1040,7 @@ static int trace_graph_entry_watchdog(struct ftrace_graph_ent *trace,
> return 0;
> }
>
> - return trace_graph_entry(trace, gops);
> + return trace_graph_entry(trace, gops, fregs);
> }
>
> static struct fgraph_ops fgraph_ops __initdata = {
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^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: [PATCH v14 05/19] function_graph: Pass ftrace_regs to retfunc
[not found] ` <172615374207.133222.13117574733580053025.stgit@devnote2>
@ 2024-09-15 8:57 ` Steven Rostedt
0 siblings, 0 replies; 3+ messages in thread
From: Steven Rostedt @ 2024-09-15 8:57 UTC (permalink / raw)
To: Paul Walmsley, Palmer Dabbelt, Albert Ou, linux-riscv
Cc: Masami Hiramatsu (Google), Florent Revest, linux-trace-kernel,
LKML, Alexei Starovoitov, Jiri Olsa, Arnaldo Carvalho de Melo,
Daniel Borkmann, Mark Rutland
Can I get an Acked-by from the RISC-V maintainers for this patch?
Thanks!
-- Steve
[ Note this is modifies the return side ]
On Fri, 13 Sep 2024 00:09:02 +0900
"Masami Hiramatsu (Google)" <mhiramat@kernel.org> wrote:
> From: Masami Hiramatsu (Google) <mhiramat@kernel.org>
>
> Pass ftrace_regs to the fgraph_ops::retfunc(). If ftrace_regs is not
> available, it passes a NULL instead. User callback function can access
> some registers (including return address) via this ftrace_regs.
>
> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
> ---
> Changes in v8:
> - Pass ftrace_regs to retfunc, instead of adding retregfunc.
> Changes in v6:
> - update to use ftrace_regs_get_return_value() because of reordering
> patches.
> Changes in v3:
> - Update for new multiple fgraph.
> - Save the return address to instruction pointer in ftrace_regs.
> ---
> include/linux/ftrace.h | 3 ++-
> kernel/trace/fgraph.c | 16 +++++++++++-----
> kernel/trace/ftrace.c | 3 ++-
> kernel/trace/trace.h | 3 ++-
> kernel/trace/trace_functions_graph.c | 7 ++++---
> kernel/trace/trace_irqsoff.c | 3 ++-
> kernel/trace/trace_sched_wakeup.c | 3 ++-
> kernel/trace/trace_selftest.c | 3 ++-
> 8 files changed, 27 insertions(+), 14 deletions(-)
>
> diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h
> index 13987cd63553..e7c41d9988e1 100644
> --- a/include/linux/ftrace.h
> +++ b/include/linux/ftrace.h
> @@ -1069,7 +1069,8 @@ struct fgraph_ops;
>
> /* Type of the callback handlers for tracing function graph*/
> typedef void (*trace_func_graph_ret_t)(struct ftrace_graph_ret *,
> - struct fgraph_ops *); /* return */
> + struct fgraph_ops *,
> + struct ftrace_regs *); /* return */
> typedef int (*trace_func_graph_ent_t)(struct ftrace_graph_ent *,
> struct fgraph_ops *,
> struct ftrace_regs *); /* entry */
> diff --git a/kernel/trace/fgraph.c b/kernel/trace/fgraph.c
> index 30bebe43607d..6a3e2db16aa4 100644
> --- a/kernel/trace/fgraph.c
> +++ b/kernel/trace/fgraph.c
> @@ -297,7 +297,8 @@ static int entry_run(struct ftrace_graph_ent *trace, struct fgraph_ops *ops,
> }
>
> /* ftrace_graph_return set to this to tell some archs to run function graph */
> -static void return_run(struct ftrace_graph_ret *trace, struct fgraph_ops *ops)
> +static void return_run(struct ftrace_graph_ret *trace, struct fgraph_ops *ops,
> + struct ftrace_regs *fregs)
> {
> }
>
> @@ -491,7 +492,8 @@ int ftrace_graph_entry_stub(struct ftrace_graph_ent *trace,
> }
>
> static void ftrace_graph_ret_stub(struct ftrace_graph_ret *trace,
> - struct fgraph_ops *gops)
> + struct fgraph_ops *gops,
> + struct ftrace_regs *fregs)
> {
> }
>
> @@ -787,6 +789,9 @@ __ftrace_return_to_handler(struct ftrace_regs *fregs, unsigned long frame_pointe
> }
>
> trace.rettime = trace_clock_local();
> + if (fregs)
> + ftrace_regs_set_instruction_pointer(fregs, ret);
> +
> #ifdef CONFIG_FUNCTION_GRAPH_RETVAL
> trace.retval = ftrace_regs_get_return_value(fregs);
> #endif
> @@ -796,7 +801,7 @@ __ftrace_return_to_handler(struct ftrace_regs *fregs, unsigned long frame_pointe
> #ifdef CONFIG_HAVE_STATIC_CALL
> if (static_branch_likely(&fgraph_do_direct)) {
> if (test_bit(fgraph_direct_gops->idx, &bitmap))
> - static_call(fgraph_retfunc)(&trace, fgraph_direct_gops);
> + static_call(fgraph_retfunc)(&trace, fgraph_direct_gops, fregs);
> } else
> #endif
> {
> @@ -806,7 +811,7 @@ __ftrace_return_to_handler(struct ftrace_regs *fregs, unsigned long frame_pointe
> if (gops == &fgraph_stub)
> continue;
>
> - gops->retfunc(&trace, gops);
> + gops->retfunc(&trace, gops, fregs);
> }
> }
>
> @@ -956,7 +961,8 @@ void ftrace_graph_sleep_time_control(bool enable)
> * Simply points to ftrace_stub, but with the proper protocol.
> * Defined by the linker script in linux/vmlinux.lds.h
> */
> -void ftrace_stub_graph(struct ftrace_graph_ret *trace, struct fgraph_ops *gops);
> +void ftrace_stub_graph(struct ftrace_graph_ret *trace, struct fgraph_ops *gops,
> + struct ftrace_regs *fregs);
>
> /* The callbacks that hook a function */
> trace_func_graph_ret_t ftrace_graph_return = ftrace_stub_graph;
> diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
> index 775040a9f541..fd6c5a50c5e5 100644
> --- a/kernel/trace/ftrace.c
> +++ b/kernel/trace/ftrace.c
> @@ -840,7 +840,8 @@ static int profile_graph_entry(struct ftrace_graph_ent *trace,
> }
>
> static void profile_graph_return(struct ftrace_graph_ret *trace,
> - struct fgraph_ops *gops)
> + struct fgraph_ops *gops,
> + struct ftrace_regs *fregs)
> {
> struct ftrace_ret_stack *ret_stack;
> struct ftrace_profile_stat *stat;
> diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
> index 28d8ad5e31e6..f4a3f75bd916 100644
> --- a/kernel/trace/trace.h
> +++ b/kernel/trace/trace.h
> @@ -682,7 +682,8 @@ void trace_latency_header(struct seq_file *m);
> void trace_default_header(struct seq_file *m);
> void print_trace_header(struct seq_file *m, struct trace_iterator *iter);
>
> -void trace_graph_return(struct ftrace_graph_ret *trace, struct fgraph_ops *gops);
> +void trace_graph_return(struct ftrace_graph_ret *trace, struct fgraph_ops *gops,
> + struct ftrace_regs *fregs);
> int trace_graph_entry(struct ftrace_graph_ent *trace, struct fgraph_ops *gops,
> struct ftrace_regs *fregs);
>
> diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c
> index b9785fc919c9..241407000109 100644
> --- a/kernel/trace/trace_functions_graph.c
> +++ b/kernel/trace/trace_functions_graph.c
> @@ -240,7 +240,7 @@ void __trace_graph_return(struct trace_array *tr,
> }
>
> void trace_graph_return(struct ftrace_graph_ret *trace,
> - struct fgraph_ops *gops)
> + struct fgraph_ops *gops, struct ftrace_regs *fregs)
> {
> unsigned long *task_var = fgraph_get_task_var(gops);
> struct trace_array *tr = gops->private;
> @@ -270,7 +270,8 @@ void trace_graph_return(struct ftrace_graph_ret *trace,
> }
>
> static void trace_graph_thresh_return(struct ftrace_graph_ret *trace,
> - struct fgraph_ops *gops)
> + struct fgraph_ops *gops,
> + struct ftrace_regs *fregs)
> {
> ftrace_graph_addr_finish(gops, trace);
>
> @@ -283,7 +284,7 @@ static void trace_graph_thresh_return(struct ftrace_graph_ret *trace,
> (trace->rettime - trace->calltime < tracing_thresh))
> return;
> else
> - trace_graph_return(trace, gops);
> + trace_graph_return(trace, gops, fregs);
> }
>
> static struct fgraph_ops funcgraph_ops = {
> diff --git a/kernel/trace/trace_irqsoff.c b/kernel/trace/trace_irqsoff.c
> index ad739d76fc86..504de7a05498 100644
> --- a/kernel/trace/trace_irqsoff.c
> +++ b/kernel/trace/trace_irqsoff.c
> @@ -208,7 +208,8 @@ static int irqsoff_graph_entry(struct ftrace_graph_ent *trace,
> }
>
> static void irqsoff_graph_return(struct ftrace_graph_ret *trace,
> - struct fgraph_ops *gops)
> + struct fgraph_ops *gops,
> + struct ftrace_regs *fregs)
> {
> struct trace_array *tr = irqsoff_trace;
> struct trace_array_cpu *data;
> diff --git a/kernel/trace/trace_sched_wakeup.c b/kernel/trace/trace_sched_wakeup.c
> index 23360a2700de..9ffbd9326898 100644
> --- a/kernel/trace/trace_sched_wakeup.c
> +++ b/kernel/trace/trace_sched_wakeup.c
> @@ -144,7 +144,8 @@ static int wakeup_graph_entry(struct ftrace_graph_ent *trace,
> }
>
> static void wakeup_graph_return(struct ftrace_graph_ret *trace,
> - struct fgraph_ops *gops)
> + struct fgraph_ops *gops,
> + struct ftrace_regs *fregs)
> {
> struct trace_array *tr = wakeup_trace;
> struct trace_array_cpu *data;
> diff --git a/kernel/trace/trace_selftest.c b/kernel/trace/trace_selftest.c
> index 89067f02094a..1ebd0899238f 100644
> --- a/kernel/trace/trace_selftest.c
> +++ b/kernel/trace/trace_selftest.c
> @@ -807,7 +807,8 @@ static __init int store_entry(struct ftrace_graph_ent *trace,
> }
>
> static __init void store_return(struct ftrace_graph_ret *trace,
> - struct fgraph_ops *gops)
> + struct fgraph_ops *gops,
> + struct ftrace_regs *fregs)
> {
> struct fgraph_fixture *fixture = container_of(gops, struct fgraph_fixture, gops);
> const char *type = fixture->store_type_name;
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^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: [PATCH v14 04/19] function_graph: Replace fgraph_ret_regs with ftrace_regs
[not found] ` <172615373091.133222.1812791604518973124.stgit@devnote2>
@ 2024-09-15 9:13 ` Steven Rostedt
0 siblings, 0 replies; 3+ messages in thread
From: Steven Rostedt @ 2024-09-15 9:13 UTC (permalink / raw)
To: Paul Walmsley, Palmer Dabbelt, Albert Ou, linux-riscv
Cc: Masami Hiramatsu (Google), Florent Revest, linux-trace-kernel,
LKML, Alexei Starovoitov, Jiri Olsa, Arnaldo Carvalho de Melo,
Daniel Borkmann, Mark Rutland
Can I get an Acked-by from the RISC-V maintainers for this patch?
Thanks!
-- Steve
On Fri, 13 Sep 2024 00:08:51 +0900
"Masami Hiramatsu (Google)" <mhiramat@kernel.org> wrote:
> From: Masami Hiramatsu (Google) <mhiramat@kernel.org>
>
> Use ftrace_regs instead of fgraph_ret_regs for tracing return value
> on function_graph tracer because of simplifying the callback interface.
>
> The CONFIG_HAVE_FUNCTION_GRAPH_RETVAL is also replaced by
> CONFIG_HAVE_FUNCTION_GRAPH_FREGS.
>
> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
> ---
> Changes in v8:
> - Newly added.
> ---
> arch/arm64/Kconfig | 1 +
> arch/arm64/include/asm/ftrace.h | 23 ++++++-----------------
> arch/arm64/kernel/asm-offsets.c | 12 ------------
> arch/arm64/kernel/entry-ftrace.S | 32 ++++++++++++++++++--------------
> arch/loongarch/Kconfig | 2 +-
> arch/loongarch/include/asm/ftrace.h | 24 ++----------------------
> arch/loongarch/kernel/asm-offsets.c | 12 ------------
> arch/loongarch/kernel/mcount.S | 17 ++++++++++-------
> arch/loongarch/kernel/mcount_dyn.S | 14 +++++++-------
> arch/riscv/Kconfig | 2 +-
> arch/riscv/include/asm/ftrace.h | 26 +++++---------------------
> arch/riscv/kernel/mcount.S | 24 +++++++++++++-----------
> arch/s390/Kconfig | 2 +-
> arch/s390/include/asm/ftrace.h | 26 +++++++++-----------------
> arch/s390/kernel/asm-offsets.c | 6 ------
> arch/s390/kernel/mcount.S | 9 +++++----
> arch/x86/Kconfig | 2 +-
> arch/x86/include/asm/ftrace.h | 22 ++--------------------
> arch/x86/kernel/ftrace_32.S | 15 +++++++++------
> arch/x86/kernel/ftrace_64.S | 17 +++++++++--------
> include/linux/ftrace.h | 14 +++++++++++---
> kernel/trace/Kconfig | 4 ++--
> kernel/trace/fgraph.c | 21 +++++++++------------
> 23 files changed, 122 insertions(+), 205 deletions(-)
>
> diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
> index a2f8ff354ca6..17947f625b06 100644
> --- a/arch/arm64/Kconfig
> +++ b/arch/arm64/Kconfig
> @@ -211,6 +211,7 @@ config ARM64
> select HAVE_FTRACE_MCOUNT_RECORD
> select HAVE_FUNCTION_TRACER
> select HAVE_FUNCTION_ERROR_INJECTION
> + select HAVE_FUNCTION_GRAPH_FREGS
> select HAVE_FUNCTION_GRAPH_TRACER
> select HAVE_FUNCTION_GRAPH_RETVAL
> select HAVE_GCC_PLUGINS
> diff --git a/arch/arm64/include/asm/ftrace.h b/arch/arm64/include/asm/ftrace.h
> index dc9cf0bd2a4c..dffaab3dd1f1 100644
> --- a/arch/arm64/include/asm/ftrace.h
> +++ b/arch/arm64/include/asm/ftrace.h
> @@ -126,6 +126,12 @@ ftrace_override_function_with_return(struct ftrace_regs *fregs)
> fregs->pc = fregs->lr;
> }
>
> +static __always_inline unsigned long
> +ftrace_regs_get_frame_pointer(const struct ftrace_regs *fregs)
> +{
> + return fregs->fp;
> +}
> +
> int ftrace_regs_query_register_offset(const char *name);
>
> int ftrace_init_nop(struct module *mod, struct dyn_ftrace *rec);
> @@ -183,23 +189,6 @@ static inline bool arch_syscall_match_sym_name(const char *sym,
>
> #ifndef __ASSEMBLY__
> #ifdef CONFIG_FUNCTION_GRAPH_TRACER
> -struct fgraph_ret_regs {
> - /* x0 - x7 */
> - unsigned long regs[8];
> -
> - unsigned long fp;
> - unsigned long __unused;
> -};
> -
> -static inline unsigned long fgraph_ret_regs_return_value(struct fgraph_ret_regs *ret_regs)
> -{
> - return ret_regs->regs[0];
> -}
> -
> -static inline unsigned long fgraph_ret_regs_frame_pointer(struct fgraph_ret_regs *ret_regs)
> -{
> - return ret_regs->fp;
> -}
>
> void prepare_ftrace_return(unsigned long self_addr, unsigned long *parent,
> unsigned long frame_pointer);
> diff --git a/arch/arm64/kernel/asm-offsets.c b/arch/arm64/kernel/asm-offsets.c
> index 27de1dddb0ab..9e03c9a7e5c3 100644
> --- a/arch/arm64/kernel/asm-offsets.c
> +++ b/arch/arm64/kernel/asm-offsets.c
> @@ -201,18 +201,6 @@ int main(void)
> DEFINE(FTRACE_OPS_FUNC, offsetof(struct ftrace_ops, func));
> #endif
> BLANK();
> -#ifdef CONFIG_FUNCTION_GRAPH_TRACER
> - DEFINE(FGRET_REGS_X0, offsetof(struct fgraph_ret_regs, regs[0]));
> - DEFINE(FGRET_REGS_X1, offsetof(struct fgraph_ret_regs, regs[1]));
> - DEFINE(FGRET_REGS_X2, offsetof(struct fgraph_ret_regs, regs[2]));
> - DEFINE(FGRET_REGS_X3, offsetof(struct fgraph_ret_regs, regs[3]));
> - DEFINE(FGRET_REGS_X4, offsetof(struct fgraph_ret_regs, regs[4]));
> - DEFINE(FGRET_REGS_X5, offsetof(struct fgraph_ret_regs, regs[5]));
> - DEFINE(FGRET_REGS_X6, offsetof(struct fgraph_ret_regs, regs[6]));
> - DEFINE(FGRET_REGS_X7, offsetof(struct fgraph_ret_regs, regs[7]));
> - DEFINE(FGRET_REGS_FP, offsetof(struct fgraph_ret_regs, fp));
> - DEFINE(FGRET_REGS_SIZE, sizeof(struct fgraph_ret_regs));
> -#endif
> #ifdef CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS
> DEFINE(FTRACE_OPS_DIRECT_CALL, offsetof(struct ftrace_ops, direct_call));
> #endif
> diff --git a/arch/arm64/kernel/entry-ftrace.S b/arch/arm64/kernel/entry-ftrace.S
> index f0c16640ef21..169ccf600066 100644
> --- a/arch/arm64/kernel/entry-ftrace.S
> +++ b/arch/arm64/kernel/entry-ftrace.S
> @@ -329,24 +329,28 @@ SYM_FUNC_END(ftrace_stub_graph)
> * @fp is checked against the value passed by ftrace_graph_caller().
> */
> SYM_CODE_START(return_to_handler)
> - /* save return value regs */
> - sub sp, sp, #FGRET_REGS_SIZE
> - stp x0, x1, [sp, #FGRET_REGS_X0]
> - stp x2, x3, [sp, #FGRET_REGS_X2]
> - stp x4, x5, [sp, #FGRET_REGS_X4]
> - stp x6, x7, [sp, #FGRET_REGS_X6]
> - str x29, [sp, #FGRET_REGS_FP] // parent's fp
> + /* Make room for ftrace_regs */
> + sub sp, sp, #FREGS_SIZE
> +
> + /* Save return value regs */
> + stp x0, x1, [sp, #FREGS_X0]
> + stp x2, x3, [sp, #FREGS_X2]
> + stp x4, x5, [sp, #FREGS_X4]
> + stp x6, x7, [sp, #FREGS_X6]
> +
> + /* Save the callsite's FP */
> + str x29, [sp, #FREGS_FP]
>
> mov x0, sp
> - bl ftrace_return_to_handler // addr = ftrace_return_to_hander(regs);
> + bl ftrace_return_to_handler // addr = ftrace_return_to_hander(fregs);
> mov x30, x0 // restore the original return address
>
> - /* restore return value regs */
> - ldp x0, x1, [sp, #FGRET_REGS_X0]
> - ldp x2, x3, [sp, #FGRET_REGS_X2]
> - ldp x4, x5, [sp, #FGRET_REGS_X4]
> - ldp x6, x7, [sp, #FGRET_REGS_X6]
> - add sp, sp, #FGRET_REGS_SIZE
> + /* Restore return value regs */
> + ldp x0, x1, [sp, #FREGS_X0]
> + ldp x2, x3, [sp, #FREGS_X2]
> + ldp x4, x5, [sp, #FREGS_X4]
> + ldp x6, x7, [sp, #FREGS_X6]
> + add sp, sp, #FREGS_SIZE
>
> ret
> SYM_CODE_END(return_to_handler)
> diff --git a/arch/loongarch/Kconfig b/arch/loongarch/Kconfig
> index 70f169210b52..974f08f65f63 100644
> --- a/arch/loongarch/Kconfig
> +++ b/arch/loongarch/Kconfig
> @@ -131,7 +131,7 @@ config LOONGARCH
> select HAVE_FTRACE_MCOUNT_RECORD
> select HAVE_FUNCTION_ARG_ACCESS_API
> select HAVE_FUNCTION_ERROR_INJECTION
> - select HAVE_FUNCTION_GRAPH_RETVAL if HAVE_FUNCTION_GRAPH_TRACER
> + select HAVE_FUNCTION_GRAPH_FREGS
> select HAVE_FUNCTION_GRAPH_TRACER
> select HAVE_FUNCTION_TRACER
> select HAVE_GCC_PLUGINS
> diff --git a/arch/loongarch/include/asm/ftrace.h b/arch/loongarch/include/asm/ftrace.h
> index 6f8517d59954..1a73f35ea9af 100644
> --- a/arch/loongarch/include/asm/ftrace.h
> +++ b/arch/loongarch/include/asm/ftrace.h
> @@ -77,6 +77,8 @@ ftrace_regs_set_instruction_pointer(struct ftrace_regs *fregs, unsigned long ip)
> override_function_with_return(&(fregs)->regs)
> #define ftrace_regs_query_register_offset(name) \
> regs_query_register_offset(name)
> +#define ftrace_regs_get_frame_pointer(fregs) \
> + ((fregs)->regs.regs[22])
>
> #define ftrace_graph_func ftrace_graph_func
> void ftrace_graph_func(unsigned long ip, unsigned long parent_ip,
> @@ -99,26 +101,4 @@ __arch_ftrace_set_direct_caller(struct pt_regs *regs, unsigned long addr)
>
> #endif /* CONFIG_FUNCTION_TRACER */
>
> -#ifndef __ASSEMBLY__
> -#ifdef CONFIG_FUNCTION_GRAPH_TRACER
> -struct fgraph_ret_regs {
> - /* a0 - a1 */
> - unsigned long regs[2];
> -
> - unsigned long fp;
> - unsigned long __unused;
> -};
> -
> -static inline unsigned long fgraph_ret_regs_return_value(struct fgraph_ret_regs *ret_regs)
> -{
> - return ret_regs->regs[0];
> -}
> -
> -static inline unsigned long fgraph_ret_regs_frame_pointer(struct fgraph_ret_regs *ret_regs)
> -{
> - return ret_regs->fp;
> -}
> -#endif /* ifdef CONFIG_FUNCTION_GRAPH_TRACER */
> -#endif
> -
> #endif /* _ASM_LOONGARCH_FTRACE_H */
> diff --git a/arch/loongarch/kernel/asm-offsets.c b/arch/loongarch/kernel/asm-offsets.c
> index bee9f7a3108f..714f5b5f1956 100644
> --- a/arch/loongarch/kernel/asm-offsets.c
> +++ b/arch/loongarch/kernel/asm-offsets.c
> @@ -279,18 +279,6 @@ static void __used output_pbe_defines(void)
> }
> #endif
>
> -#ifdef CONFIG_FUNCTION_GRAPH_TRACER
> -static void __used output_fgraph_ret_regs_defines(void)
> -{
> - COMMENT("LoongArch fgraph_ret_regs offsets.");
> - OFFSET(FGRET_REGS_A0, fgraph_ret_regs, regs[0]);
> - OFFSET(FGRET_REGS_A1, fgraph_ret_regs, regs[1]);
> - OFFSET(FGRET_REGS_FP, fgraph_ret_regs, fp);
> - DEFINE(FGRET_REGS_SIZE, sizeof(struct fgraph_ret_regs));
> - BLANK();
> -}
> -#endif
> -
> static void __used output_kvm_defines(void)
> {
> COMMENT("KVM/LoongArch Specific offsets.");
> diff --git a/arch/loongarch/kernel/mcount.S b/arch/loongarch/kernel/mcount.S
> index 3015896016a0..b6850503e061 100644
> --- a/arch/loongarch/kernel/mcount.S
> +++ b/arch/loongarch/kernel/mcount.S
> @@ -79,10 +79,11 @@ SYM_FUNC_START(ftrace_graph_caller)
> SYM_FUNC_END(ftrace_graph_caller)
>
> SYM_FUNC_START(return_to_handler)
> - PTR_ADDI sp, sp, -FGRET_REGS_SIZE
> - PTR_S a0, sp, FGRET_REGS_A0
> - PTR_S a1, sp, FGRET_REGS_A1
> - PTR_S zero, sp, FGRET_REGS_FP
> + /* Save return value regs */
> + PTR_ADDI sp, sp, -PT_SIZE
> + PTR_S a0, sp, PT_R4
> + PTR_S a1, sp, PT_R5
> + PTR_S zero, sp, PT_R22
>
> move a0, sp
> bl ftrace_return_to_handler
> @@ -90,9 +91,11 @@ SYM_FUNC_START(return_to_handler)
> /* Restore the real parent address: a0 -> ra */
> move ra, a0
>
> - PTR_L a0, sp, FGRET_REGS_A0
> - PTR_L a1, sp, FGRET_REGS_A1
> - PTR_ADDI sp, sp, FGRET_REGS_SIZE
> + /* Restore return value regs */
> + PTR_L a0, sp, PT_R4
> + PTR_L a1, sp, PT_R5
> + PTR_ADDI sp, sp, PT_SIZE
> +
> jr ra
> SYM_FUNC_END(return_to_handler)
> #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
> diff --git a/arch/loongarch/kernel/mcount_dyn.S b/arch/loongarch/kernel/mcount_dyn.S
> index 0c65cf09110c..d6b474ad1d5e 100644
> --- a/arch/loongarch/kernel/mcount_dyn.S
> +++ b/arch/loongarch/kernel/mcount_dyn.S
> @@ -140,19 +140,19 @@ SYM_CODE_END(ftrace_graph_caller)
> SYM_CODE_START(return_to_handler)
> UNWIND_HINT_UNDEFINED
> /* Save return value regs */
> - PTR_ADDI sp, sp, -FGRET_REGS_SIZE
> - PTR_S a0, sp, FGRET_REGS_A0
> - PTR_S a1, sp, FGRET_REGS_A1
> - PTR_S zero, sp, FGRET_REGS_FP
> + PTR_ADDI sp, sp, -PT_SIZE
> + PTR_S a0, sp, PT_R4
> + PTR_S a1, sp, PT_R5
> + PTR_S zero, sp, PT_R22
>
> move a0, sp
> bl ftrace_return_to_handler
> move ra, a0
>
> /* Restore return value regs */
> - PTR_L a0, sp, FGRET_REGS_A0
> - PTR_L a1, sp, FGRET_REGS_A1
> - PTR_ADDI sp, sp, FGRET_REGS_SIZE
> + PTR_L a0, sp, PT_R4
> + PTR_L a1, sp, PT_R5
> + PTR_ADDI sp, sp, PT_SIZE
>
> jr ra
> SYM_CODE_END(return_to_handler)
> diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
> index 0f3cd7c3a436..6e8422269ba4 100644
> --- a/arch/riscv/Kconfig
> +++ b/arch/riscv/Kconfig
> @@ -140,7 +140,7 @@ config RISCV
> select HAVE_DYNAMIC_FTRACE_WITH_ARGS if HAVE_DYNAMIC_FTRACE
> select HAVE_FTRACE_MCOUNT_RECORD if !XIP_KERNEL
> select HAVE_FUNCTION_GRAPH_TRACER
> - select HAVE_FUNCTION_GRAPH_RETVAL if HAVE_FUNCTION_GRAPH_TRACER
> + select HAVE_FUNCTION_GRAPH_FREGS
> select HAVE_FUNCTION_TRACER if !XIP_KERNEL && !PREEMPTION
> select HAVE_EBPF_JIT if MMU
> select HAVE_GUP_FAST if MMU
> diff --git a/arch/riscv/include/asm/ftrace.h b/arch/riscv/include/asm/ftrace.h
> index 2cddd79ff21b..e9f364ce9fe8 100644
> --- a/arch/riscv/include/asm/ftrace.h
> +++ b/arch/riscv/include/asm/ftrace.h
> @@ -164,6 +164,11 @@ static __always_inline unsigned long ftrace_regs_get_stack_pointer(const struct
> return fregs->sp;
> }
>
> +static __always_inline unsigned long ftrace_regs_get_frame_pointer(const struct ftrace_regs *fregs)
> +{
> + return fregs->s0;
> +}
> +
> static __always_inline unsigned long ftrace_regs_get_argument(struct ftrace_regs *fregs,
> unsigned int n)
> {
> @@ -204,25 +209,4 @@ static inline void arch_ftrace_set_direct_caller(struct ftrace_regs *fregs, unsi
>
> #endif /* CONFIG_DYNAMIC_FTRACE */
>
> -#ifndef __ASSEMBLY__
> -#ifdef CONFIG_FUNCTION_GRAPH_TRACER
> -struct fgraph_ret_regs {
> - unsigned long a1;
> - unsigned long a0;
> - unsigned long s0;
> - unsigned long ra;
> -};
> -
> -static inline unsigned long fgraph_ret_regs_return_value(struct fgraph_ret_regs *ret_regs)
> -{
> - return ret_regs->a0;
> -}
> -
> -static inline unsigned long fgraph_ret_regs_frame_pointer(struct fgraph_ret_regs *ret_regs)
> -{
> - return ret_regs->s0;
> -}
> -#endif /* ifdef CONFIG_FUNCTION_GRAPH_TRACER */
> -#endif
> -
> #endif /* _ASM_RISCV_FTRACE_H */
> diff --git a/arch/riscv/kernel/mcount.S b/arch/riscv/kernel/mcount.S
> index 3a42f6287909..068168046e0e 100644
> --- a/arch/riscv/kernel/mcount.S
> +++ b/arch/riscv/kernel/mcount.S
> @@ -12,6 +12,8 @@
> #include <asm/asm-offsets.h>
> #include <asm/ftrace.h>
>
> +#define ABI_SIZE_ON_STACK 80
> +
> .text
>
> .macro SAVE_ABI_STATE
> @@ -26,12 +28,12 @@
> * register if a0 was not saved.
> */
> .macro SAVE_RET_ABI_STATE
> - addi sp, sp, -4*SZREG
> - REG_S s0, 2*SZREG(sp)
> - REG_S ra, 3*SZREG(sp)
> - REG_S a0, 1*SZREG(sp)
> - REG_S a1, 0*SZREG(sp)
> - addi s0, sp, 4*SZREG
> + addi sp, sp, -ABI_SIZE_ON_STACK
> + REG_S ra, 1*SZREG(sp)
> + REG_S s0, 8*SZREG(sp)
> + REG_S a0, 10*SZREG(sp)
> + REG_S a1, 11*SZREG(sp)
> + addi s0, sp, ABI_SIZE_ON_STACK
> .endm
>
> .macro RESTORE_ABI_STATE
> @@ -41,11 +43,11 @@
> .endm
>
> .macro RESTORE_RET_ABI_STATE
> - REG_L ra, 3*SZREG(sp)
> - REG_L s0, 2*SZREG(sp)
> - REG_L a0, 1*SZREG(sp)
> - REG_L a1, 0*SZREG(sp)
> - addi sp, sp, 4*SZREG
> + REG_L ra, 1*SZREG(sp)
> + REG_L s0, 8*SZREG(sp)
> + REG_L a0, 10*SZREG(sp)
> + REG_L a1, 11*SZREG(sp)
> + addi sp, sp, ABI_SIZE_ON_STACK
> .endm
>
> SYM_TYPED_FUNC_START(ftrace_stub)
> diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
> index a822f952f64a..12e942cfbcde 100644
> --- a/arch/s390/Kconfig
> +++ b/arch/s390/Kconfig
> @@ -184,7 +184,7 @@ config S390
> select HAVE_FTRACE_MCOUNT_RECORD
> select HAVE_FUNCTION_ARG_ACCESS_API
> select HAVE_FUNCTION_ERROR_INJECTION
> - select HAVE_FUNCTION_GRAPH_RETVAL
> + select HAVE_FUNCTION_GRAPH_FREGS
> select HAVE_FUNCTION_GRAPH_TRACER
> select HAVE_FUNCTION_TRACER
> select HAVE_GCC_PLUGINS
> diff --git a/arch/s390/include/asm/ftrace.h b/arch/s390/include/asm/ftrace.h
> index de76c21eb4a3..9cdd48a46bf7 100644
> --- a/arch/s390/include/asm/ftrace.h
> +++ b/arch/s390/include/asm/ftrace.h
> @@ -49,23 +49,6 @@ static __always_inline struct pt_regs *arch_ftrace_get_regs(struct ftrace_regs *
> return NULL;
> }
>
> -#ifdef CONFIG_FUNCTION_GRAPH_TRACER
> -struct fgraph_ret_regs {
> - unsigned long gpr2;
> - unsigned long fp;
> -};
> -
> -static __always_inline unsigned long fgraph_ret_regs_return_value(struct fgraph_ret_regs *ret_regs)
> -{
> - return ret_regs->gpr2;
> -}
> -
> -static __always_inline unsigned long fgraph_ret_regs_frame_pointer(struct fgraph_ret_regs *ret_regs)
> -{
> - return ret_regs->fp;
> -}
> -#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
> -
> static __always_inline unsigned long
> ftrace_regs_get_instruction_pointer(const struct ftrace_regs *fregs)
> {
> @@ -92,6 +75,15 @@ ftrace_regs_set_instruction_pointer(struct ftrace_regs *fregs,
> #define ftrace_regs_query_register_offset(name) \
> regs_query_register_offset(name)
>
> +static __always_inline unsigned long
> +ftrace_regs_get_frame_pointer(struct ftrace_regs *fregs)
> +{
> + unsigned long *sp;
> +
> + sp = (void *)ftrace_regs_get_stack_pointer(fregs);
> + return sp[0]; /* return backchain */
> +}
> +
> #ifdef CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS
> /*
> * When an ftrace registered caller is tracing a function that is
> diff --git a/arch/s390/kernel/asm-offsets.c b/arch/s390/kernel/asm-offsets.c
> index ffa0dd2dbaac..d38ed80615d5 100644
> --- a/arch/s390/kernel/asm-offsets.c
> +++ b/arch/s390/kernel/asm-offsets.c
> @@ -179,12 +179,6 @@ int main(void)
> DEFINE(OLDMEM_SIZE, PARMAREA + offsetof(struct parmarea, oldmem_size));
> DEFINE(COMMAND_LINE, PARMAREA + offsetof(struct parmarea, command_line));
> DEFINE(MAX_COMMAND_LINE_SIZE, PARMAREA + offsetof(struct parmarea, max_command_line_size));
> -#ifdef CONFIG_FUNCTION_GRAPH_TRACER
> - /* function graph return value tracing */
> - OFFSET(__FGRAPH_RET_GPR2, fgraph_ret_regs, gpr2);
> - OFFSET(__FGRAPH_RET_FP, fgraph_ret_regs, fp);
> - DEFINE(__FGRAPH_RET_SIZE, sizeof(struct fgraph_ret_regs));
> -#endif
> OFFSET(__FTRACE_REGS_PT_REGS, ftrace_regs, regs);
> DEFINE(__FTRACE_REGS_SIZE, sizeof(struct ftrace_regs));
>
> diff --git a/arch/s390/kernel/mcount.S b/arch/s390/kernel/mcount.S
> index ae4d4fd9afcd..cda798b976de 100644
> --- a/arch/s390/kernel/mcount.S
> +++ b/arch/s390/kernel/mcount.S
> @@ -133,14 +133,15 @@ SYM_CODE_END(ftrace_common)
> SYM_FUNC_START(return_to_handler)
> stmg %r2,%r5,32(%r15)
> lgr %r1,%r15
> - aghi %r15,-(STACK_FRAME_OVERHEAD+__FGRAPH_RET_SIZE)
> +# Allocate ftrace_regs + backchain on the stack
> + aghi %r15,-STACK_FRAME_SIZE_FREGS
> stg %r1,__SF_BACKCHAIN(%r15)
> la %r3,STACK_FRAME_OVERHEAD(%r15)
> - stg %r1,__FGRAPH_RET_FP(%r3)
> - stg %r2,__FGRAPH_RET_GPR2(%r3)
> + stg %r2,(__SF_GPRS+2*8)(%r15)
> + stg %r15,(__SF_GPRS+15*8)(%r15)
> lgr %r2,%r3
> brasl %r14,ftrace_return_to_handler
> - aghi %r15,STACK_FRAME_OVERHEAD+__FGRAPH_RET_SIZE
> + aghi %r15,STACK_FRAME_SIZE_FREGS
> lgr %r14,%r2
> lmg %r2,%r5,32(%r15)
> BR_EX %r14
> diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
> index 007bab9f2a0e..047384e4d93a 100644
> --- a/arch/x86/Kconfig
> +++ b/arch/x86/Kconfig
> @@ -228,7 +228,7 @@ config X86
> select HAVE_GUP_FAST
> select HAVE_FENTRY if X86_64 || DYNAMIC_FTRACE
> select HAVE_FTRACE_MCOUNT_RECORD
> - select HAVE_FUNCTION_GRAPH_RETVAL if HAVE_FUNCTION_GRAPH_TRACER
> + select HAVE_FUNCTION_GRAPH_FREGS if HAVE_FUNCTION_GRAPH_TRACER
> select HAVE_FUNCTION_GRAPH_TRACER if X86_32 || (X86_64 && DYNAMIC_FTRACE)
> select HAVE_FUNCTION_TRACER
> select HAVE_GCC_PLUGINS
> diff --git a/arch/x86/include/asm/ftrace.h b/arch/x86/include/asm/ftrace.h
> index 78f6a200e15b..669771ef3b5b 100644
> --- a/arch/x86/include/asm/ftrace.h
> +++ b/arch/x86/include/asm/ftrace.h
> @@ -64,6 +64,8 @@ arch_ftrace_get_regs(struct ftrace_regs *fregs)
> override_function_with_return(&(fregs)->regs)
> #define ftrace_regs_query_register_offset(name) \
> regs_query_register_offset(name)
> +#define ftrace_regs_get_frame_pointer(fregs) \
> + frame_pointer(&(fregs)->regs)
>
> struct ftrace_ops;
> #define ftrace_graph_func ftrace_graph_func
> @@ -148,24 +150,4 @@ static inline bool arch_trace_is_compat_syscall(struct pt_regs *regs)
> #endif /* !COMPILE_OFFSETS */
> #endif /* !__ASSEMBLY__ */
>
> -#ifndef __ASSEMBLY__
> -#ifdef CONFIG_FUNCTION_GRAPH_TRACER
> -struct fgraph_ret_regs {
> - unsigned long ax;
> - unsigned long dx;
> - unsigned long bp;
> -};
> -
> -static inline unsigned long fgraph_ret_regs_return_value(struct fgraph_ret_regs *ret_regs)
> -{
> - return ret_regs->ax;
> -}
> -
> -static inline unsigned long fgraph_ret_regs_frame_pointer(struct fgraph_ret_regs *ret_regs)
> -{
> - return ret_regs->bp;
> -}
> -#endif /* ifdef CONFIG_FUNCTION_GRAPH_TRACER */
> -#endif
> -
> #endif /* _ASM_X86_FTRACE_H */
> diff --git a/arch/x86/kernel/ftrace_32.S b/arch/x86/kernel/ftrace_32.S
> index 58d9ed50fe61..4b265884d06c 100644
> --- a/arch/x86/kernel/ftrace_32.S
> +++ b/arch/x86/kernel/ftrace_32.S
> @@ -23,6 +23,8 @@ SYM_FUNC_START(__fentry__)
> SYM_FUNC_END(__fentry__)
> EXPORT_SYMBOL(__fentry__)
>
> +#define FRAME_SIZE PT_OLDSS+4
> +
> SYM_CODE_START(ftrace_caller)
>
> #ifdef CONFIG_FRAME_POINTER
> @@ -187,14 +189,15 @@ SYM_CODE_END(ftrace_graph_caller)
>
> .globl return_to_handler
> return_to_handler:
> - pushl $0
> - pushl %edx
> - pushl %eax
> + subl $(FRAME_SIZE), %esp
> + movl $0, PT_EBP(%esp)
> + movl %edx, PT_EDX(%esp)
> + movl %eax, PT_EAX(%esp)
> movl %esp, %eax
> call ftrace_return_to_handler
> movl %eax, %ecx
> - popl %eax
> - popl %edx
> - addl $4, %esp # skip ebp
> + movl %eax, PT_EAX(%esp)
> + movl %edx, PT_EDX(%esp)
> + addl $(FRAME_SIZE), %esp
> JMP_NOSPEC ecx
> #endif
> diff --git a/arch/x86/kernel/ftrace_64.S b/arch/x86/kernel/ftrace_64.S
> index 214f30e9f0c0..d51647228596 100644
> --- a/arch/x86/kernel/ftrace_64.S
> +++ b/arch/x86/kernel/ftrace_64.S
> @@ -348,21 +348,22 @@ STACK_FRAME_NON_STANDARD_FP(__fentry__)
> SYM_CODE_START(return_to_handler)
> UNWIND_HINT_UNDEFINED
> ANNOTATE_NOENDBR
> - subq $24, %rsp
>
> - /* Save the return values */
> - movq %rax, (%rsp)
> - movq %rdx, 8(%rsp)
> - movq %rbp, 16(%rsp)
> + /* Save ftrace_regs for function exit context */
> + subq $(FRAME_SIZE), %rsp
> +
> + movq %rax, RAX(%rsp)
> + movq %rdx, RDX(%rsp)
> + movq %rbp, RBP(%rsp)
> movq %rsp, %rdi
>
> call ftrace_return_to_handler
>
> movq %rax, %rdi
> - movq 8(%rsp), %rdx
> - movq (%rsp), %rax
> + movq RDX(%rsp), %rdx
> + movq RAX(%rsp), %rax
>
> - addq $24, %rsp
> + addq $(FRAME_SIZE), %rsp
> /*
> * Jump back to the old return address. This cannot be JMP_NOSPEC rdi
> * since IBT would demand that contain ENDBR, which simply isn't so for
> diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h
> index 1fe49a28de2d..13987cd63553 100644
> --- a/include/linux/ftrace.h
> +++ b/include/linux/ftrace.h
> @@ -43,9 +43,8 @@ struct dyn_ftrace;
>
> char *arch_ftrace_match_adjust(char *str, const char *search);
>
> -#ifdef CONFIG_HAVE_FUNCTION_GRAPH_RETVAL
> -struct fgraph_ret_regs;
> -unsigned long ftrace_return_to_handler(struct fgraph_ret_regs *ret_regs);
> +#ifdef CONFIG_HAVE_FUNCTION_GRAPH_FREGS
> +unsigned long ftrace_return_to_handler(struct ftrace_regs *fregs);
> #else
> unsigned long ftrace_return_to_handler(unsigned long frame_pointer);
> #endif
> @@ -134,6 +133,13 @@ extern int ftrace_enabled;
> * Also, architecture dependent fields can be used for internal process.
> * (e.g. orig_ax on x86_64)
> *
> + * Basically, ftrace_regs stores the registers related to the context.
> + * On function entry, registers for function parameters and hooking the
> + * function call are stored, and on function exit, registers for function
> + * return value and frame pointers are stored.
> + *
> + * And also, it dpends on the context that which registers are restored
> + * from the ftrace_regs.
> * On the function entry, those registers will be restored except for
> * the stack pointer, so that user can change the function parameters
> * and instruction pointer (e.g. live patching.)
> @@ -191,6 +197,8 @@ static __always_inline bool ftrace_regs_has_args(struct ftrace_regs *fregs)
> override_function_with_return(ftrace_get_regs(fregs))
> #define ftrace_regs_query_register_offset(name) \
> regs_query_register_offset(name)
> +#define ftrace_regs_get_frame_pointer(fregs) \
> + frame_pointer(&(fregs)->regs)
> #endif
>
> typedef void (*ftrace_func_t)(unsigned long ip, unsigned long parent_ip,
> diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig
> index 721c3b221048..ab277eff80dc 100644
> --- a/kernel/trace/Kconfig
> +++ b/kernel/trace/Kconfig
> @@ -31,7 +31,7 @@ config HAVE_FUNCTION_GRAPH_TRACER
> help
> See Documentation/trace/ftrace-design.rst
>
> -config HAVE_FUNCTION_GRAPH_RETVAL
> +config HAVE_FUNCTION_GRAPH_FREGS
> bool
>
> config HAVE_DYNAMIC_FTRACE
> @@ -232,7 +232,7 @@ config FUNCTION_GRAPH_TRACER
>
> config FUNCTION_GRAPH_RETVAL
> bool "Kernel Function Graph Return Value"
> - depends on HAVE_FUNCTION_GRAPH_RETVAL
> + depends on HAVE_FUNCTION_GRAPH_FREGS
> depends on FUNCTION_GRAPH_TRACER
> default n
> help
> diff --git a/kernel/trace/fgraph.c b/kernel/trace/fgraph.c
> index 0322c5723748..30bebe43607d 100644
> --- a/kernel/trace/fgraph.c
> +++ b/kernel/trace/fgraph.c
> @@ -763,15 +763,12 @@ static struct notifier_block ftrace_suspend_notifier = {
> .notifier_call = ftrace_suspend_notifier_call,
> };
>
> -/* fgraph_ret_regs is not defined without CONFIG_FUNCTION_GRAPH_RETVAL */
> -struct fgraph_ret_regs;
> -
> /*
> * Send the trace to the ring-buffer.
> * @return the original return address.
> */
> -static unsigned long __ftrace_return_to_handler(struct fgraph_ret_regs *ret_regs,
> - unsigned long frame_pointer)
> +static inline unsigned long
> +__ftrace_return_to_handler(struct ftrace_regs *fregs, unsigned long frame_pointer)
> {
> struct ftrace_ret_stack *ret_stack;
> struct ftrace_graph_ret trace;
> @@ -791,7 +788,7 @@ static unsigned long __ftrace_return_to_handler(struct fgraph_ret_regs *ret_regs
>
> trace.rettime = trace_clock_local();
> #ifdef CONFIG_FUNCTION_GRAPH_RETVAL
> - trace.retval = fgraph_ret_regs_return_value(ret_regs);
> + trace.retval = ftrace_regs_get_return_value(fregs);
> #endif
>
> bitmap = get_bitmap_bits(current, offset);
> @@ -826,14 +823,14 @@ static unsigned long __ftrace_return_to_handler(struct fgraph_ret_regs *ret_regs
> }
>
> /*
> - * After all architecures have selected HAVE_FUNCTION_GRAPH_RETVAL, we can
> - * leave only ftrace_return_to_handler(ret_regs).
> + * After all architecures have selected HAVE_FUNCTION_GRAPH_FREGS, we can
> + * leave only ftrace_return_to_handler(fregs).
> */
> -#ifdef CONFIG_HAVE_FUNCTION_GRAPH_RETVAL
> -unsigned long ftrace_return_to_handler(struct fgraph_ret_regs *ret_regs)
> +#ifdef CONFIG_HAVE_FUNCTION_GRAPH_FREGS
> +unsigned long ftrace_return_to_handler(struct ftrace_regs *fregs)
> {
> - return __ftrace_return_to_handler(ret_regs,
> - fgraph_ret_regs_frame_pointer(ret_regs));
> + return __ftrace_return_to_handler(fregs,
> + ftrace_regs_get_frame_pointer(fregs));
> }
> #else
> unsigned long ftrace_return_to_handler(unsigned long frame_pointer)
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2024-09-15 8:56 ` [PATCH v14 03/19] function_graph: Pass ftrace_regs to entryfunc Steven Rostedt
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