diff mbox series

[v11,5/8] riscv: ftrace: Enable HAVE_FUNCTION_GRAPH_RETVAL

Message ID a8d71b12259f90e7e63d0ea654fcac95b0232bbc.1680954589.git.pengdonglin@sangfor.com.cn (mailing list archive)
State Accepted
Commit b97aec082b51a0728adc9f69494826d32e0d1f8f
Headers show
Series function_graph: Support recording and printing the return value of function | expand

Commit Message

pengdonglin April 8, 2023, 12:42 p.m. UTC 
The previous patch ("function_graph: Support recording and printing
the return value of function") has laid the groundwork for the for
the funcgraph-retval, and this modification makes it available on
the RISC-V platform.

We introduce a new structure called fgraph_ret_regs for the RISC-V
platform to hold return registers and the frame pointer. We then
fill its content in the return_to_handler and pass its address to
the function ftrace_return_to_handler to record the return value.

Signed-off-by: Donglin Peng <pengdonglin@sangfor.com.cn>
---
v10:
 - Use CONFIG_FUNCTION_GRAPH_TRACER to control fgraph_ret_regs definition

v9:
 - Update the commit message

v8:
 - Modify the control range of CONFIG_HAVE_FUNCTION_GRAPH_RETVAL
---
 arch/riscv/Kconfig              |  1 +
 arch/riscv/include/asm/ftrace.h | 21 +++++++++++++++++++++
 arch/riscv/kernel/mcount.S      |  7 +------
 3 files changed, 23 insertions(+), 6 deletions(-)

Comments

Steven Rostedt June 9, 2023, 1:58 a.m. UTC | #1 
Can I get an ack from a RISC-V maintainer?

-- Steve


On Sat,  8 Apr 2023 05:42:19 -0700
Donglin Peng <pengdonglin@sangfor.com.cn> wrote:

> The previous patch ("function_graph: Support recording and printing
> the return value of function") has laid the groundwork for the for
> the funcgraph-retval, and this modification makes it available on
> the RISC-V platform.
> 
> We introduce a new structure called fgraph_ret_regs for the RISC-V
> platform to hold return registers and the frame pointer. We then
> fill its content in the return_to_handler and pass its address to
> the function ftrace_return_to_handler to record the return value.
> 
> Signed-off-by: Donglin Peng <pengdonglin@sangfor.com.cn>
> ---
> v10:
>  - Use CONFIG_FUNCTION_GRAPH_TRACER to control fgraph_ret_regs definition
> 
> v9:
>  - Update the commit message
> 
> v8:
>  - Modify the control range of CONFIG_HAVE_FUNCTION_GRAPH_RETVAL
> ---
>  arch/riscv/Kconfig              |  1 +
>  arch/riscv/include/asm/ftrace.h | 21 +++++++++++++++++++++
>  arch/riscv/kernel/mcount.S      |  7 +------
>  3 files changed, 23 insertions(+), 6 deletions(-)
> 
> diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
> index eb7f29a412f8..108538815309 100644
> --- a/arch/riscv/Kconfig
> +++ b/arch/riscv/Kconfig
> @@ -139,6 +139,7 @@ config RISCV
>  	select HAVE_DYNAMIC_FTRACE if !XIP_KERNEL && MMU && $(cc-option,-fpatchable-function-entry=8)
>  	select HAVE_DYNAMIC_FTRACE_WITH_REGS if HAVE_DYNAMIC_FTRACE
>  	select HAVE_FTRACE_MCOUNT_RECORD if !XIP_KERNEL
> +	select HAVE_FUNCTION_GRAPH_RETVAL if HAVE_FUNCTION_GRAPH_TRACER
>  	select HAVE_FUNCTION_GRAPH_TRACER
>  	select HAVE_FUNCTION_TRACER if !XIP_KERNEL && !PREEMPTION
>  
> diff --git a/arch/riscv/include/asm/ftrace.h b/arch/riscv/include/asm/ftrace.h
> index d47d87c2d7e3..740a979171e5 100644
> --- a/arch/riscv/include/asm/ftrace.h
> +++ b/arch/riscv/include/asm/ftrace.h
> @@ -111,4 +111,25 @@ int ftrace_init_nop(struct module *mod, struct dyn_ftrace *rec);
>  
>  #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 30102aadc4d7..8a6e5a9e842a 100644
> --- a/arch/riscv/kernel/mcount.S
> +++ b/arch/riscv/kernel/mcount.S
> @@ -65,13 +65,8 @@ ENTRY(return_to_handler)
>   * So alternatively we check the *old* frame pointer position, that is, the
>   * value stored in -16(s0) on entry, and the s0 on return.
>   */
> -#ifdef HAVE_FUNCTION_GRAPH_FP_TEST
> -	mv	t6, s0
> -#endif
>  	SAVE_RET_ABI_STATE
> -#ifdef HAVE_FUNCTION_GRAPH_FP_TEST
> -	mv	a0, t6
> -#endif
> +	mv	a0, sp
>  	call	ftrace_return_to_handler
>  	mv	a2, a0
>  	RESTORE_RET_ABI_STATE
Palmer Dabbelt June 20, 2023, 7:54 p.m. UTC | #2 
On Thu, 08 Jun 2023 18:58:34 PDT (-0700), rostedt@goodmis.org wrote:
>
> Can I get an ack from a RISC-V maintainer?

Sorry I missed this.

Acked-by: Palmer Dabbelt <palmer@rivosinc.com>

>
> -- Steve
>
>
> On Sat,  8 Apr 2023 05:42:19 -0700
> Donglin Peng <pengdonglin@sangfor.com.cn> wrote:
>
>> The previous patch ("function_graph: Support recording and printing
>> the return value of function") has laid the groundwork for the for
>> the funcgraph-retval, and this modification makes it available on
>> the RISC-V platform.
>>
>> We introduce a new structure called fgraph_ret_regs for the RISC-V
>> platform to hold return registers and the frame pointer. We then
>> fill its content in the return_to_handler and pass its address to
>> the function ftrace_return_to_handler to record the return value.
>>
>> Signed-off-by: Donglin Peng <pengdonglin@sangfor.com.cn>
>> ---
>> v10:
>>  - Use CONFIG_FUNCTION_GRAPH_TRACER to control fgraph_ret_regs definition
>>
>> v9:
>>  - Update the commit message
>>
>> v8:
>>  - Modify the control range of CONFIG_HAVE_FUNCTION_GRAPH_RETVAL
>> ---
>>  arch/riscv/Kconfig              |  1 +
>>  arch/riscv/include/asm/ftrace.h | 21 +++++++++++++++++++++
>>  arch/riscv/kernel/mcount.S      |  7 +------
>>  3 files changed, 23 insertions(+), 6 deletions(-)
>>
>> diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
>> index eb7f29a412f8..108538815309 100644
>> --- a/arch/riscv/Kconfig
>> +++ b/arch/riscv/Kconfig
>> @@ -139,6 +139,7 @@ config RISCV
>>  	select HAVE_DYNAMIC_FTRACE if !XIP_KERNEL && MMU && $(cc-option,-fpatchable-function-entry=8)
>>  	select HAVE_DYNAMIC_FTRACE_WITH_REGS if HAVE_DYNAMIC_FTRACE
>>  	select HAVE_FTRACE_MCOUNT_RECORD if !XIP_KERNEL
>> +	select HAVE_FUNCTION_GRAPH_RETVAL if HAVE_FUNCTION_GRAPH_TRACER
>>  	select HAVE_FUNCTION_GRAPH_TRACER
>>  	select HAVE_FUNCTION_TRACER if !XIP_KERNEL && !PREEMPTION
>>
>> diff --git a/arch/riscv/include/asm/ftrace.h b/arch/riscv/include/asm/ftrace.h
>> index d47d87c2d7e3..740a979171e5 100644
>> --- a/arch/riscv/include/asm/ftrace.h
>> +++ b/arch/riscv/include/asm/ftrace.h
>> @@ -111,4 +111,25 @@ int ftrace_init_nop(struct module *mod, struct dyn_ftrace *rec);
>>
>>  #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 30102aadc4d7..8a6e5a9e842a 100644
>> --- a/arch/riscv/kernel/mcount.S
>> +++ b/arch/riscv/kernel/mcount.S
>> @@ -65,13 +65,8 @@ ENTRY(return_to_handler)
>>   * So alternatively we check the *old* frame pointer position, that is, the
>>   * value stored in -16(s0) on entry, and the s0 on return.
>>   */
>> -#ifdef HAVE_FUNCTION_GRAPH_FP_TEST
>> -	mv	t6, s0
>> -#endif
>>  	SAVE_RET_ABI_STATE
>> -#ifdef HAVE_FUNCTION_GRAPH_FP_TEST
>> -	mv	a0, t6
>> -#endif
>> +	mv	a0, sp
>>  	call	ftrace_return_to_handler
>>  	mv	a2, a0
>>  	RESTORE_RET_ABI_STATE
diff mbox series

Patch

diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
index eb7f29a412f8..108538815309 100644
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig
@@ -139,6 +139,7 @@  config RISCV
 	select HAVE_DYNAMIC_FTRACE if !XIP_KERNEL && MMU && $(cc-option,-fpatchable-function-entry=8)
 	select HAVE_DYNAMIC_FTRACE_WITH_REGS if HAVE_DYNAMIC_FTRACE
 	select HAVE_FTRACE_MCOUNT_RECORD if !XIP_KERNEL
+	select HAVE_FUNCTION_GRAPH_RETVAL if HAVE_FUNCTION_GRAPH_TRACER
 	select HAVE_FUNCTION_GRAPH_TRACER
 	select HAVE_FUNCTION_TRACER if !XIP_KERNEL && !PREEMPTION
 
diff --git a/arch/riscv/include/asm/ftrace.h b/arch/riscv/include/asm/ftrace.h
index d47d87c2d7e3..740a979171e5 100644
--- a/arch/riscv/include/asm/ftrace.h
+++ b/arch/riscv/include/asm/ftrace.h
@@ -111,4 +111,25 @@  int ftrace_init_nop(struct module *mod, struct dyn_ftrace *rec);
 
 #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 30102aadc4d7..8a6e5a9e842a 100644
--- a/arch/riscv/kernel/mcount.S
+++ b/arch/riscv/kernel/mcount.S
@@ -65,13 +65,8 @@  ENTRY(return_to_handler)
  * So alternatively we check the *old* frame pointer position, that is, the
  * value stored in -16(s0) on entry, and the s0 on return.
  */
-#ifdef HAVE_FUNCTION_GRAPH_FP_TEST
-	mv	t6, s0
-#endif
 	SAVE_RET_ABI_STATE
-#ifdef HAVE_FUNCTION_GRAPH_FP_TEST
-	mv	a0, t6
-#endif
+	mv	a0, sp
 	call	ftrace_return_to_handler
 	mv	a2, a0
 	RESTORE_RET_ABI_STATE