When both "dest" and "src" are aligned, copying the data in chunks
(grub_addr_t) is more efficient than a byte-by-byte copy.
Also tweak '__aeabi_memcpy()', '__aeabi_memcpy4()', and
'__aeabi_memcpy8()', since 'grub_memcpy()' is not inline anymore.
Optimization for unaligned buffers was omitted to maintain code
simplicity and readability. The current chunk-copy optimization
for aligned buffers already provides a noticeable performance
improvement(*) for Argon2 keyslot decryption.
(*) On my system, for a LUKS2 keyslot configured with a 1 GB Argon2
memory requirement, this patch reduces the decryption time from 22
seconds to 12 seconds.
Signed-off-by: Gary Lin <[email protected]>
---
grub-core/kern/compiler-rt.c | 8 ++++----
grub-core/kern/misc.c | 31 +++++++++++++++++++++++++++++++
include/grub/misc.h | 8 +-------
3 files changed, 36 insertions(+), 11 deletions(-)
diff --git a/grub-core/kern/compiler-rt.c b/grub-core/kern/compiler-rt.c
index eda689a0c..8f3865e95 100644
--- a/grub-core/kern/compiler-rt.c
+++ b/grub-core/kern/compiler-rt.c
@@ -24,7 +24,7 @@
void * GRUB_BUILTIN_ATTR
memcpy (void *dest, const void *src, grub_size_t n)
{
- return grub_memmove (dest, src, n);
+ return grub_memcpy (dest, src, n);
}
void * GRUB_BUILTIN_ATTR
memmove (void *dest, const void *src, grub_size_t n)
@@ -372,11 +372,11 @@ grub_int32_t
__aeabi_idiv (grub_int32_t a, grub_int32_t b)
__attribute__ ((alias ("__divsi3")));
void *__aeabi_memcpy (void *dest, const void *src, grub_size_t n)
- __attribute__ ((alias ("grub_memcpy")));
+ __attribute__ ((alias ("memcpy")));
void *__aeabi_memcpy4 (void *dest, const void *src, grub_size_t n)
- __attribute__ ((alias ("grub_memcpy")));
+ __attribute__ ((alias ("memcpy")));
void *__aeabi_memcpy8 (void *dest, const void *src, grub_size_t n)
- __attribute__ ((alias ("grub_memcpy")));
+ __attribute__ ((alias ("memcpy")));
void *__aeabi_memset (void *s, int c, grub_size_t n)
__attribute__ ((alias ("memset")));
diff --git a/grub-core/kern/misc.c b/grub-core/kern/misc.c
index b9ac86c18..db9623224 100644
--- a/grub-core/kern/misc.c
+++ b/grub-core/kern/misc.c
@@ -99,6 +99,37 @@ grub_memmove (void *dest, const void *src, grub_size_t n)
return dest;
}
+static void *
+__memcpy_aligned (void *dest, const void *src, grub_size_t n)
+{
+ grub_addr_t *dw = (grub_addr_t *) dest;
+ const grub_addr_t *sw = (const grub_addr_t *) src;
+ grub_uint8_t *d;
+ const grub_uint8_t *s;
+
+ for (; n >= sizeof (grub_addr_t); n -= sizeof (grub_addr_t))
+ *dw++ = *sw++;
+
+ d = (grub_uint8_t *) dw;
+ s = (const grub_uint8_t *) sw;
+ for (; n > 0; n--)
+ *d++ = *s++;
+
+ return dest;
+}
+
+void *
+grub_memcpy (void *dest, const void *src, grub_size_t n)
+{
+ /* Check if 'dest' and 'src' are aligned */
+ if (((grub_addr_t) dest & (sizeof (grub_addr_t) - 1)) == 0 &&
+ ((grub_addr_t) src & (sizeof (grub_addr_t) - 1)) == 0 &&
+ n >= sizeof (grub_addr_t))
+ return __memcpy_aligned (dest, src, n);
+
+ return grub_memmove (dest, src, n);
+}
+
char *
grub_strcpy (char *dest, const char *src)
{
diff --git a/include/grub/misc.h b/include/grub/misc.h
index 0d2bab7dd..1bb63231a 100644
--- a/include/grub/misc.h
+++ b/include/grub/misc.h
@@ -38,6 +38,7 @@
#define grub_dprintf(condition, ...) grub_real_dprintf(GRUB_FILE,
__FUNCTION__, __LINE__, condition, __VA_ARGS__)
void *EXPORT_FUNC(grub_memmove) (void *dest, const void *src, grub_size_t n);
+void *EXPORT_FUNC(grub_memcpy) (void *dest, const void *src, grub_size_t n);
char *EXPORT_FUNC(grub_strcpy) (char *dest, const char *src);
static inline char *
@@ -103,13 +104,6 @@ grub_strlcpy (char *dest, const char *src, grub_size_t
size)
return res;
}
-/* XXX: If grub_memmove is too slow, we must implement grub_memcpy. */
-static inline void *
-grub_memcpy (void *dest, const void *src, grub_size_t n)
-{
- return grub_memmove (dest, src, n);
-}
-
#if defined(__x86_64__) && !defined (GRUB_UTIL)
#if defined (__MINGW32__) || defined (__CYGWIN__) || defined (__MINGW64__)
#define GRUB_ASM_ATTR __attribute__ ((sysv_abi))
--
2.51.0
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