Unverified Commit 56c1c1a0 authored by Samuel Holland's avatar Samuel Holland Committed by Palmer Dabbelt
Browse files

riscv: Add tracepoints for SBI calls and returns 



These are useful for measuring the latency of SBI calls. The SBI HSM
extension is excluded because those functions are called from contexts
such as cpuidle where instrumentation is not allowed.

Reviewed-by: default avatarAndrew Jones <ajones@ventanamicro.com>
Signed-off-by: default avatarSamuel Holland <samuel.holland@sifive.com>
Link: https://lore.kernel.org/r/20240321230131.1838105-1-samuel.holland@sifive.com


Signed-off-by: default avatarPalmer Dabbelt <palmer@rivosinc.com>
parent a43fe27d

arch/riscv/include/asm/trace.h

0 → 100644
+54 −0
Original line number Diff line number Diff line 
/* SPDX-License-Identifier: GPL-2.0 */

#undef TRACE_SYSTEM

#define TRACE_SYSTEM riscv



#if !defined(_TRACE_RISCV_H) || defined(TRACE_HEADER_MULTI_READ)

#define _TRACE_RISCV_H



#include <linux/tracepoint.h>



TRACE_EVENT_CONDITION(sbi_call,

	TP_PROTO(int ext, int fid),

	TP_ARGS(ext, fid),

	TP_CONDITION(ext != SBI_EXT_HSM),



	TP_STRUCT__entry(

		__field(int, ext)

		__field(int, fid)

	),



	TP_fast_assign(

		__entry->ext = ext;

		__entry->fid = fid;

	),



	TP_printk("ext=0x%x fid=%d", __entry->ext, __entry->fid)

);



TRACE_EVENT_CONDITION(sbi_return,

	TP_PROTO(int ext, long error, long value),

	TP_ARGS(ext, error, value),

	TP_CONDITION(ext != SBI_EXT_HSM),



	TP_STRUCT__entry(

		__field(long, error)

		__field(long, value)

	),



	TP_fast_assign(

		__entry->error = error;

		__entry->value = value;

	),



	TP_printk("error=%ld value=0x%lx", __entry->error, __entry->value)

);



#endif /* _TRACE_RISCV_H */



#undef TRACE_INCLUDE_PATH

#undef TRACE_INCLUDE_FILE



#define TRACE_INCLUDE_PATH asm

#define TRACE_INCLUDE_FILE trace



#include <trace/define_trace.h>

arch/riscv/kernel/sbi.c

+7 −0
Original line number Diff line number Diff line
@@ -14,6 +14,9 @@ 
#include <asm/smp.h>

#include <asm/tlbflush.h>



#define CREATE_TRACE_POINTS

#include <asm/trace.h>



/* default SBI version is 0.1 */

unsigned long sbi_spec_version __ro_after_init = SBI_SPEC_VERSION_DEFAULT;

EXPORT_SYMBOL(sbi_spec_version);
@@ -31,6 +34,8 @@ struct sbiret sbi_ecall(int ext, int fid, unsigned long arg0, 
{

	struct sbiret ret;



	trace_sbi_call(ext, fid);



	register uintptr_t a0 asm ("a0") = (uintptr_t)(arg0);

	register uintptr_t a1 asm ("a1") = (uintptr_t)(arg1);

	register uintptr_t a2 asm ("a2") = (uintptr_t)(arg2);
@@ -46,6 +51,8 @@ struct sbiret sbi_ecall(int ext, int fid, unsigned long arg0, 
	ret.error = a0;

	ret.value = a1;



	trace_sbi_return(ext, ret.error, ret.value);



	return ret;

}

EXPORT_SYMBOL(sbi_ecall);