[PATCH 19/25] xor: avoid indirect calls for arm64-optimized ops

From: Christoph Hellwig

Date: Thu Feb 26 2026 - 10:44:05 EST


Remove the inner xor_block_templates, and instead have two separate
actual template that call into the neon-enabled compilation unit.

Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
arch/arm64/include/asm/xor.h | 13 ++--
lib/raid/xor/arm64/xor-neon-glue.c | 95 +++++++++++++++---------------
lib/raid/xor/arm64/xor-neon.c | 73 +++++++++--------------
lib/raid/xor/arm64/xor-neon.h | 30 ++++++++++
4 files changed, 114 insertions(+), 97 deletions(-)
create mode 100644 lib/raid/xor/arm64/xor-neon.h

diff --git a/arch/arm64/include/asm/xor.h b/arch/arm64/include/asm/xor.h
index 81718f010761..4782c760bcac 100644
--- a/arch/arm64/include/asm/xor.h
+++ b/arch/arm64/include/asm/xor.h
@@ -7,15 +7,18 @@
#include <asm-generic/xor.h>
#include <asm/simd.h>

-extern struct xor_block_template xor_block_arm64;
-void __init xor_neon_init(void);
+extern struct xor_block_template xor_block_neon;
+extern struct xor_block_template xor_block_eor3;

#define arch_xor_init arch_xor_init
static __always_inline void __init arch_xor_init(void)
{
- xor_neon_init();
xor_register(&xor_block_8regs);
xor_register(&xor_block_32regs);
- if (cpu_has_neon())
- xor_register(&xor_block_arm64);
+ if (cpu_has_neon()) {
+ if (cpu_have_named_feature(SHA3))
+ xor_register(&xor_block_eor3);
+ else
+ xor_register(&xor_block_neon);
+ }
}
diff --git a/lib/raid/xor/arm64/xor-neon-glue.c b/lib/raid/xor/arm64/xor-neon-glue.c
index 067a2095659a..08c3e3573388 100644
--- a/lib/raid/xor/arm64/xor-neon-glue.c
+++ b/lib/raid/xor/arm64/xor-neon-glue.c
@@ -7,51 +7,54 @@
#include <linux/raid/xor_impl.h>
#include <asm/simd.h>
#include <asm/xor.h>
+#include "xor-neon.h"

-extern struct xor_block_template const xor_block_inner_neon;
-
-static void
-xor_neon_2(unsigned long bytes, unsigned long * __restrict p1,
- const unsigned long * __restrict p2)
-{
- scoped_ksimd()
- xor_block_inner_neon.do_2(bytes, p1, p2);
-}
-
-static void
-xor_neon_3(unsigned long bytes, unsigned long * __restrict p1,
- const unsigned long * __restrict p2,
- const unsigned long * __restrict p3)
-{
- scoped_ksimd()
- xor_block_inner_neon.do_3(bytes, p1, p2, p3);
-}
-
-static void
-xor_neon_4(unsigned long bytes, unsigned long * __restrict p1,
- const unsigned long * __restrict p2,
- const unsigned long * __restrict p3,
- const unsigned long * __restrict p4)
-{
- scoped_ksimd()
- xor_block_inner_neon.do_4(bytes, p1, p2, p3, p4);
-}
-
-static void
-xor_neon_5(unsigned long bytes, unsigned long * __restrict p1,
- const unsigned long * __restrict p2,
- const unsigned long * __restrict p3,
- const unsigned long * __restrict p4,
- const unsigned long * __restrict p5)
-{
- scoped_ksimd()
- xor_block_inner_neon.do_5(bytes, p1, p2, p3, p4, p5);
-}
-
-struct xor_block_template xor_block_arm64 = {
- .name = "arm64_neon",
- .do_2 = xor_neon_2,
- .do_3 = xor_neon_3,
- .do_4 = xor_neon_4,
- .do_5 = xor_neon_5
+#define XOR_TEMPLATE(_name) \
+static void \
+xor_##_name##_2(unsigned long bytes, unsigned long * __restrict p1, \
+ const unsigned long * __restrict p2) \
+{ \
+ scoped_ksimd() \
+ __xor_##_name##_2(bytes, p1, p2); \
+} \
+ \
+static void \
+xor_##_name##_3(unsigned long bytes, unsigned long * __restrict p1, \
+ const unsigned long * __restrict p2, \
+ const unsigned long * __restrict p3) \
+{ \
+ scoped_ksimd() \
+ __xor_##_name##_3(bytes, p1, p2, p3); \
+} \
+ \
+static void \
+xor_##_name##_4(unsigned long bytes, unsigned long * __restrict p1, \
+ const unsigned long * __restrict p2, \
+ const unsigned long * __restrict p3, \
+ const unsigned long * __restrict p4) \
+{ \
+ scoped_ksimd() \
+ __xor_##_name##_4(bytes, p1, p2, p3, p4); \
+} \
+ \
+static void \
+xor_##_name##_5(unsigned long bytes, unsigned long * __restrict p1, \
+ const unsigned long * __restrict p2, \
+ const unsigned long * __restrict p3, \
+ const unsigned long * __restrict p4, \
+ const unsigned long * __restrict p5) \
+{ \
+ scoped_ksimd() \
+ __xor_##_name##_5(bytes, p1, p2, p3, p4, p5); \
+} \
+ \
+struct xor_block_template xor_block_##_name = { \
+ .name = __stringify(_name), \
+ .do_2 = xor_##_name##_2, \
+ .do_3 = xor_##_name##_3, \
+ .do_4 = xor_##_name##_4, \
+ .do_5 = xor_##_name##_5 \
};
+
+XOR_TEMPLATE(neon);
+XOR_TEMPLATE(eor3);
diff --git a/lib/raid/xor/arm64/xor-neon.c b/lib/raid/xor/arm64/xor-neon.c
index 8d2d185090db..61194c292917 100644
--- a/lib/raid/xor/arm64/xor-neon.c
+++ b/lib/raid/xor/arm64/xor-neon.c
@@ -8,9 +8,10 @@
#include <linux/cache.h>
#include <asm/neon-intrinsics.h>
#include <asm/xor.h>
+#include "xor-neon.h"

-static void xor_arm64_neon_2(unsigned long bytes, unsigned long * __restrict p1,
- const unsigned long * __restrict p2)
+void __xor_neon_2(unsigned long bytes, unsigned long * __restrict p1,
+ const unsigned long * __restrict p2)
{
uint64_t *dp1 = (uint64_t *)p1;
uint64_t *dp2 = (uint64_t *)p2;
@@ -36,9 +37,9 @@ static void xor_arm64_neon_2(unsigned long bytes, unsigned long * __restrict p1,
} while (--lines > 0);
}

-static void xor_arm64_neon_3(unsigned long bytes, unsigned long * __restrict p1,
- const unsigned long * __restrict p2,
- const unsigned long * __restrict p3)
+void __xor_neon_3(unsigned long bytes, unsigned long * __restrict p1,
+ const unsigned long * __restrict p2,
+ const unsigned long * __restrict p3)
{
uint64_t *dp1 = (uint64_t *)p1;
uint64_t *dp2 = (uint64_t *)p2;
@@ -72,10 +73,10 @@ static void xor_arm64_neon_3(unsigned long bytes, unsigned long * __restrict p1,
} while (--lines > 0);
}

-static void xor_arm64_neon_4(unsigned long bytes, unsigned long * __restrict p1,
- const unsigned long * __restrict p2,
- const unsigned long * __restrict p3,
- const unsigned long * __restrict p4)
+void __xor_neon_4(unsigned long bytes, unsigned long * __restrict p1,
+ const unsigned long * __restrict p2,
+ const unsigned long * __restrict p3,
+ const unsigned long * __restrict p4)
{
uint64_t *dp1 = (uint64_t *)p1;
uint64_t *dp2 = (uint64_t *)p2;
@@ -117,11 +118,11 @@ static void xor_arm64_neon_4(unsigned long bytes, unsigned long * __restrict p1,
} while (--lines > 0);
}

-static void xor_arm64_neon_5(unsigned long bytes, unsigned long * __restrict p1,
- const unsigned long * __restrict p2,
- const unsigned long * __restrict p3,
- const unsigned long * __restrict p4,
- const unsigned long * __restrict p5)
+void __xor_neon_5(unsigned long bytes, unsigned long * __restrict p1,
+ const unsigned long * __restrict p2,
+ const unsigned long * __restrict p3,
+ const unsigned long * __restrict p4,
+ const unsigned long * __restrict p5)
{
uint64_t *dp1 = (uint64_t *)p1;
uint64_t *dp2 = (uint64_t *)p2;
@@ -171,14 +172,6 @@ static void xor_arm64_neon_5(unsigned long bytes, unsigned long * __restrict p1,
} while (--lines > 0);
}

-struct xor_block_template xor_block_inner_neon __ro_after_init = {
- .name = "__inner_neon__",
- .do_2 = xor_arm64_neon_2,
- .do_3 = xor_arm64_neon_3,
- .do_4 = xor_arm64_neon_4,
- .do_5 = xor_arm64_neon_5,
-};
-
static inline uint64x2_t eor3(uint64x2_t p, uint64x2_t q, uint64x2_t r)
{
uint64x2_t res;
@@ -189,10 +182,9 @@ static inline uint64x2_t eor3(uint64x2_t p, uint64x2_t q, uint64x2_t r)
return res;
}

-static void xor_arm64_eor3_3(unsigned long bytes,
- unsigned long * __restrict p1,
- const unsigned long * __restrict p2,
- const unsigned long * __restrict p3)
+void __xor_eor3_3(unsigned long bytes, unsigned long * __restrict p1,
+ const unsigned long * __restrict p2,
+ const unsigned long * __restrict p3)
{
uint64_t *dp1 = (uint64_t *)p1;
uint64_t *dp2 = (uint64_t *)p2;
@@ -224,11 +216,10 @@ static void xor_arm64_eor3_3(unsigned long bytes,
} while (--lines > 0);
}

-static void xor_arm64_eor3_4(unsigned long bytes,
- unsigned long * __restrict p1,
- const unsigned long * __restrict p2,
- const unsigned long * __restrict p3,
- const unsigned long * __restrict p4)
+void __xor_eor3_4(unsigned long bytes, unsigned long * __restrict p1,
+ const unsigned long * __restrict p2,
+ const unsigned long * __restrict p3,
+ const unsigned long * __restrict p4)
{
uint64_t *dp1 = (uint64_t *)p1;
uint64_t *dp2 = (uint64_t *)p2;
@@ -268,12 +259,11 @@ static void xor_arm64_eor3_4(unsigned long bytes,
} while (--lines > 0);
}

-static void xor_arm64_eor3_5(unsigned long bytes,
- unsigned long * __restrict p1,
- const unsigned long * __restrict p2,
- const unsigned long * __restrict p3,
- const unsigned long * __restrict p4,
- const unsigned long * __restrict p5)
+void __xor_eor3_5(unsigned long bytes, unsigned long * __restrict p1,
+ const unsigned long * __restrict p2,
+ const unsigned long * __restrict p3,
+ const unsigned long * __restrict p4,
+ const unsigned long * __restrict p5)
{
uint64_t *dp1 = (uint64_t *)p1;
uint64_t *dp2 = (uint64_t *)p2;
@@ -314,12 +304,3 @@ static void xor_arm64_eor3_5(unsigned long bytes,
dp5 += 8;
} while (--lines > 0);
}
-
-void __init xor_neon_init(void)
-{
- if (cpu_have_named_feature(SHA3)) {
- xor_block_inner_neon.do_3 = xor_arm64_eor3_3;
- xor_block_inner_neon.do_4 = xor_arm64_eor3_4;
- xor_block_inner_neon.do_5 = xor_arm64_eor3_5;
- }
-}
diff --git a/lib/raid/xor/arm64/xor-neon.h b/lib/raid/xor/arm64/xor-neon.h
new file mode 100644
index 000000000000..cec0ac846fea
--- /dev/null
+++ b/lib/raid/xor/arm64/xor-neon.h
@@ -0,0 +1,30 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+void __xor_neon_2(unsigned long bytes, unsigned long * __restrict p1,
+ const unsigned long * __restrict p2);
+void __xor_neon_3(unsigned long bytes, unsigned long * __restrict p1,
+ const unsigned long * __restrict p2,
+ const unsigned long * __restrict p3);
+void __xor_neon_4(unsigned long bytes, unsigned long * __restrict p1,
+ const unsigned long * __restrict p2,
+ const unsigned long * __restrict p3,
+ const unsigned long * __restrict p4);
+void __xor_neon_5(unsigned long bytes, unsigned long * __restrict p1,
+ const unsigned long * __restrict p2,
+ const unsigned long * __restrict p3,
+ const unsigned long * __restrict p4,
+ const unsigned long * __restrict p5);
+
+#define __xor_eor3_2 __xor_neon_2
+void __xor_eor3_3(unsigned long bytes, unsigned long * __restrict p1,
+ const unsigned long * __restrict p2,
+ const unsigned long * __restrict p3);
+void __xor_eor3_4(unsigned long bytes, unsigned long * __restrict p1,
+ const unsigned long * __restrict p2,
+ const unsigned long * __restrict p3,
+ const unsigned long * __restrict p4);
+void __xor_eor3_5(unsigned long bytes, unsigned long * __restrict p1,
+ const unsigned long * __restrict p2,
+ const unsigned long * __restrict p3,
+ const unsigned long * __restrict p4,
+ const unsigned long * __restrict p5);
--
2.47.3