Patch "riscv: Add tracepoints for SBI calls and returns" has been added to the 6.10-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    riscv: Add tracepoints for SBI calls and returns

to the 6.10-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     riscv-add-tracepoints-for-sbi-calls-and-returns.patch
and it can be found in the queue-6.10 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit ac9399cdf90e8e8f81e08b798c8d49612709c238
Author: Samuel Holland <samuel.holland@xxxxxxxxxx>
Date:   Thu Mar 21 16:01:25 2024 -0700

    riscv: Add tracepoints for SBI calls and returns
    
    [ Upstream commit 56c1c1a09ab93c7b7c957860f01f8600d6c03143 ]
    
    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: Andrew Jones <ajones@xxxxxxxxxxxxxxxx>
    Signed-off-by: Samuel Holland <samuel.holland@xxxxxxxxxx>
    Link: https://lore.kernel.org/r/20240321230131.1838105-1-samuel.holland@xxxxxxxxxx
    Signed-off-by: Palmer Dabbelt <palmer@xxxxxxxxxxxx>
    Stable-dep-of: 1ff95eb2bebd ("riscv: Fix RISCV_ALTERNATIVE_EARLY")
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/arch/riscv/include/asm/trace.h b/arch/riscv/include/asm/trace.h
new file mode 100644
index 000000000000..6151cee5450c
--- /dev/null
+++ b/arch/riscv/include/asm/trace.h
@@ -0,0 +1,54 @@
+/* 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>
diff --git a/arch/riscv/kernel/sbi.c b/arch/riscv/kernel/sbi.c
index e66e0999a800..a1d21d8f5293 100644
--- a/arch/riscv/kernel/sbi.c
+++ b/arch/riscv/kernel/sbi.c
@@ -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);