aboutsummaryrefslogtreecommitdiffstats
path: root/arch/arc/lib/memset-archs.S
diff options
context:
space:
mode:
authorMauro Carvalho Chehab <mchehab+samsung@kernel.org>2019-02-18 10:12:12 -0500
committerMauro Carvalho Chehab <mchehab+samsung@kernel.org>2019-02-18 10:12:12 -0500
commit5f09bc8cc4010a3ea17c5881a62fc45192ebe7b0 (patch)
treec8e30ba4eaf357699ef97a786bf56661f4591be8 /arch/arc/lib/memset-archs.S
parentmedia: vimc: fill in bus_info in media_device_info (diff)
parentLinux 5.0-rc7 (diff)
downloadlinux-dev-5f09bc8cc4010a3ea17c5881a62fc45192ebe7b0.tar.xz
linux-dev-5f09bc8cc4010a3ea17c5881a62fc45192ebe7b0.zip
Merge tag 'v5.0-rc7' into patchwork
Linux 5.0-rc7 * tag 'v5.0-rc7': (1667 commits) Linux 5.0-rc7 Input: elan_i2c - add ACPI ID for touchpad in Lenovo V330-15ISK Input: st-keyscan - fix potential zalloc NULL dereference Input: apanel - switch to using brightness_set_blocking() powerpc/64s: Fix possible corruption on big endian due to pgd/pud_present() efi/arm: Revert "Defer persistent reservations until after paging_init()" arm64, mm, efi: Account for GICv3 LPI tables in static memblock reserve table sunrpc: fix 4 more call sites that were using stack memory with a scatterlist include/linux/module.h: copy __init/__exit attrs to init/cleanup_module Compiler Attributes: add support for __copy (gcc >= 9) lib/crc32.c: mark crc32_le_base/__crc32c_le_base aliases as __pure auxdisplay: ht16k33: fix potential user-after-free on module unload x86/platform/UV: Use efi_runtime_lock to serialise BIOS calls i2c: bcm2835: Clear current buffer pointers and counts after a transfer i2c: cadence: Fix the hold bit setting drm: Use array_size() when creating lease dm thin: fix bug where bio that overwrites thin block ignores FUA Revert "exec: load_script: don't blindly truncate shebang string" Revert "gfs2: read journal in large chunks to locate the head" net: ethernet: freescale: set FEC ethtool regs version ... Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Diffstat (limited to 'arch/arc/lib/memset-archs.S')
-rw-r--r--arch/arc/lib/memset-archs.S40
1 files changed, 32 insertions, 8 deletions
diff --git a/arch/arc/lib/memset-archs.S b/arch/arc/lib/memset-archs.S
index 62ad4bcb841a..f230bb7092fd 100644
--- a/arch/arc/lib/memset-archs.S
+++ b/arch/arc/lib/memset-archs.S
@@ -7,11 +7,39 @@
*/
#include <linux/linkage.h>
+#include <asm/cache.h>
-#undef PREALLOC_NOT_AVAIL
+/*
+ * The memset implementation below is optimized to use prefetchw and prealloc
+ * instruction in case of CPU with 64B L1 data cache line (L1_CACHE_SHIFT == 6)
+ * If you want to implement optimized memset for other possible L1 data cache
+ * line lengths (32B and 128B) you should rewrite code carefully checking
+ * we don't call any prefetchw/prealloc instruction for L1 cache lines which
+ * don't belongs to memset area.
+ */
+
+#if L1_CACHE_SHIFT == 6
+
+.macro PREALLOC_INSTR reg, off
+ prealloc [\reg, \off]
+.endm
+
+.macro PREFETCHW_INSTR reg, off
+ prefetchw [\reg, \off]
+.endm
+
+#else
+
+.macro PREALLOC_INSTR
+.endm
+
+.macro PREFETCHW_INSTR
+.endm
+
+#endif
ENTRY_CFI(memset)
- prefetchw [r0] ; Prefetch the write location
+ PREFETCHW_INSTR r0, 0 ; Prefetch the first write location
mov.f 0, r2
;;; if size is zero
jz.d [blink]
@@ -48,11 +76,8 @@ ENTRY_CFI(memset)
lpnz @.Lset64bytes
;; LOOP START
-#ifdef PREALLOC_NOT_AVAIL
- prefetchw [r3, 64] ;Prefetch the next write location
-#else
- prealloc [r3, 64]
-#endif
+ PREALLOC_INSTR r3, 64 ; alloc next line w/o fetching
+
#ifdef CONFIG_ARC_HAS_LL64
std.ab r4, [r3, 8]
std.ab r4, [r3, 8]
@@ -85,7 +110,6 @@ ENTRY_CFI(memset)
lsr.f lp_count, r2, 5 ;Last remaining max 124 bytes
lpnz .Lset32bytes
;; LOOP START
- prefetchw [r3, 32] ;Prefetch the next write location
#ifdef CONFIG_ARC_HAS_LL64
std.ab r4, [r3, 8]
std.ab r4, [r3, 8]