WSL2-Linux-Kernel/arch/alpha/lib/ev6-memset.S

606 строки
16 KiB
ArmAsm
Исходник Обычный вид История

License cleanup: add SPDX GPL-2.0 license identifier to files with no license Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-01 17:07:57 +03:00
/* SPDX-License-Identifier: GPL-2.0 */
/*
* arch/alpha/lib/ev6-memset.S
*
* This is an efficient (and relatively small) implementation of the C library
* "memset()" function for the 21264 implementation of Alpha.
*
* 21264 version contributed by Rick Gorton <rick.gorton@alpha-processor.com>
*
* Much of the information about 21264 scheduling/coding comes from:
* Compiler Writer's Guide for the Alpha 21264
* abbreviated as 'CWG' in other comments here
* ftp.digital.com/pub/Digital/info/semiconductor/literature/dsc-library.html
* Scheduling notation:
* E - either cluster
* U - upper subcluster; U0 - subcluster U0; U1 - subcluster U1
* L - lower subcluster; L0 - subcluster L0; L1 - subcluster L1
* The algorithm for the leading and trailing quadwords remains the same,
* however the loop has been unrolled to enable better memory throughput,
* and the code has been replicated for each of the entry points: __memset
* and __memset16 to permit better scheduling to eliminate the stalling
* encountered during the mask replication.
* A future enhancement might be to put in a byte store loop for really
* small (say < 32 bytes) memset()s. Whether or not that change would be
* a win in the kernel would depend upon the contextual usage.
* WARNING: Maintaining this is going to be more work than the above version,
* as fixes will need to be made in multiple places. The performance gain
* is worth it.
*/
#include <asm/export.h>
.set noat
.set noreorder
.text
.globl memset
.globl __memset
.globl ___memset
.globl __memset16
.globl __constant_c_memset
.ent ___memset
.align 5
___memset:
.frame $30,0,$26,0
.prologue 0
/*
* Serious stalling happens. The only way to mitigate this is to
* undertake a major re-write to interleave the constant materialization
* with other parts of the fall-through code. This is important, even
* though it makes maintenance tougher.
* Do this later.
*/
and $17,255,$1 # E : 00000000000000ch
insbl $17,1,$2 # U : 000000000000ch00
bis $16,$16,$0 # E : return value
ble $18,end_b # U : zero length requested?
addq $18,$16,$6 # E : max address to write to
bis $1,$2,$17 # E : 000000000000chch
insbl $1,2,$3 # U : 0000000000ch0000
insbl $1,3,$4 # U : 00000000ch000000
or $3,$4,$3 # E : 00000000chch0000
inswl $17,4,$5 # U : 0000chch00000000
xor $16,$6,$1 # E : will complete write be within one quadword?
inswl $17,6,$2 # U : chch000000000000
or $17,$3,$17 # E : 00000000chchchch
or $2,$5,$2 # E : chchchch00000000
bic $1,7,$1 # E : fit within a single quadword?
and $16,7,$3 # E : Target addr misalignment
or $17,$2,$17 # E : chchchchchchchch
beq $1,within_quad_b # U :
nop # E :
beq $3,aligned_b # U : target is 0mod8
/*
* Target address is misaligned, and won't fit within a quadword
*/
ldq_u $4,0($16) # L : Fetch first partial
bis $16,$16,$5 # E : Save the address
insql $17,$16,$2 # U : Insert new bytes
subq $3,8,$3 # E : Invert (for addressing uses)
addq $18,$3,$18 # E : $18 is new count ($3 is negative)
mskql $4,$16,$4 # U : clear relevant parts of the quad
subq $16,$3,$16 # E : $16 is new aligned destination
bis $2,$4,$1 # E : Final bytes
nop
stq_u $1,0($5) # L : Store result
nop
nop
.align 4
aligned_b:
/*
* We are now guaranteed to be quad aligned, with at least
* one partial quad to write.
*/
sra $18,3,$3 # U : Number of remaining quads to write
and $18,7,$18 # E : Number of trailing bytes to write
bis $16,$16,$5 # E : Save dest address
beq $3,no_quad_b # U : tail stuff only
/*
* it's worth the effort to unroll this and use wh64 if possible
* Lifted a bunch of code from clear_user.S
* At this point, entry values are:
* $16 Current destination address
* $5 A copy of $16
* $6 The max quadword address to write to
* $18 Number trailer bytes
* $3 Number quads to write
*/
and $16, 0x3f, $2 # E : Forward work (only useful for unrolled loop)
subq $3, 16, $4 # E : Only try to unroll if > 128 bytes
subq $2, 0x40, $1 # E : bias counter (aligning stuff 0mod64)
blt $4, loop_b # U :
/*
* We know we've got at least 16 quads, minimum of one trip
* through unrolled loop. Do a quad at a time to get us 0mod64
* aligned.
*/
nop # E :
nop # E :
nop # E :
beq $1, $bigalign_b # U :
$alignmod64_b:
stq $17, 0($5) # L :
subq $3, 1, $3 # E : For consistency later
addq $1, 8, $1 # E : Increment towards zero for alignment
addq $5, 8, $4 # E : Initial wh64 address (filler instruction)
nop
nop
addq $5, 8, $5 # E : Inc address
blt $1, $alignmod64_b # U :
$bigalign_b:
/*
* $3 - number quads left to go
* $5 - target address (aligned 0mod64)
* $17 - mask of stuff to store
* Scratch registers available: $7, $2, $4, $1
* we know that we'll be taking a minimum of one trip through
* CWG Section 3.7.6: do not expect a sustained store rate of > 1/cycle
* Assumes the wh64 needs to be for 2 trips through the loop in the future
* The wh64 is issued on for the starting destination address for trip +2
* through the loop, and if there are less than two trips left, the target
* address will be for the current trip.
*/
$do_wh64_b:
wh64 ($4) # L1 : memory subsystem write hint
subq $3, 24, $2 # E : For determining future wh64 addresses
stq $17, 0($5) # L :
nop # E :
addq $5, 128, $4 # E : speculative target of next wh64
stq $17, 8($5) # L :
stq $17, 16($5) # L :
addq $5, 64, $7 # E : Fallback address for wh64 (== next trip addr)
stq $17, 24($5) # L :
stq $17, 32($5) # L :
cmovlt $2, $7, $4 # E : Latency 2, extra mapping cycle
nop
stq $17, 40($5) # L :
stq $17, 48($5) # L :
subq $3, 16, $2 # E : Repeat the loop at least once more?
nop
stq $17, 56($5) # L :
addq $5, 64, $5 # E :
subq $3, 8, $3 # E :
bge $2, $do_wh64_b # U :
nop
nop
nop
beq $3, no_quad_b # U : Might have finished already
.align 4
/*
* Simple loop for trailing quadwords, or for small amounts
* of data (where we can't use an unrolled loop and wh64)
*/
loop_b:
stq $17,0($5) # L :
subq $3,1,$3 # E : Decrement number quads left
addq $5,8,$5 # E : Inc address
bne $3,loop_b # U : more?
no_quad_b:
/*
* Write 0..7 trailing bytes.
*/
nop # E :
beq $18,end_b # U : All done?
ldq $7,0($5) # L :
mskqh $7,$6,$2 # U : Mask final quad
insqh $17,$6,$4 # U : New bits
bis $2,$4,$1 # E : Put it all together
stq $1,0($5) # L : And back to memory
ret $31,($26),1 # L0 :
within_quad_b:
ldq_u $1,0($16) # L :
insql $17,$16,$2 # U : New bits
mskql $1,$16,$4 # U : Clear old
bis $2,$4,$2 # E : New result
mskql $2,$6,$4 # U :
mskqh $1,$6,$2 # U :
bis $2,$4,$1 # E :
stq_u $1,0($16) # L :
end_b:
nop
nop
nop
ret $31,($26),1 # L0 :
.end ___memset
EXPORT_SYMBOL(___memset)
/*
* This is the original body of code, prior to replication and
* rescheduling. Leave it here, as there may be calls to this
* entry point.
*/
.align 4
.ent __constant_c_memset
__constant_c_memset:
.frame $30,0,$26,0
.prologue 0
addq $18,$16,$6 # E : max address to write to
bis $16,$16,$0 # E : return value
xor $16,$6,$1 # E : will complete write be within one quadword?
ble $18,end # U : zero length requested?
bic $1,7,$1 # E : fit within a single quadword
beq $1,within_one_quad # U :
and $16,7,$3 # E : Target addr misalignment
beq $3,aligned # U : target is 0mod8
/*
* Target address is misaligned, and won't fit within a quadword
*/
ldq_u $4,0($16) # L : Fetch first partial
bis $16,$16,$5 # E : Save the address
insql $17,$16,$2 # U : Insert new bytes
subq $3,8,$3 # E : Invert (for addressing uses)
addq $18,$3,$18 # E : $18 is new count ($3 is negative)
mskql $4,$16,$4 # U : clear relevant parts of the quad
subq $16,$3,$16 # E : $16 is new aligned destination
bis $2,$4,$1 # E : Final bytes
nop
stq_u $1,0($5) # L : Store result
nop
nop
.align 4
aligned:
/*
* We are now guaranteed to be quad aligned, with at least
* one partial quad to write.
*/
sra $18,3,$3 # U : Number of remaining quads to write
and $18,7,$18 # E : Number of trailing bytes to write
bis $16,$16,$5 # E : Save dest address
beq $3,no_quad # U : tail stuff only
/*
* it's worth the effort to unroll this and use wh64 if possible
* Lifted a bunch of code from clear_user.S
* At this point, entry values are:
* $16 Current destination address
* $5 A copy of $16
* $6 The max quadword address to write to
* $18 Number trailer bytes
* $3 Number quads to write
*/
and $16, 0x3f, $2 # E : Forward work (only useful for unrolled loop)
subq $3, 16, $4 # E : Only try to unroll if > 128 bytes
subq $2, 0x40, $1 # E : bias counter (aligning stuff 0mod64)
blt $4, loop # U :
/*
* We know we've got at least 16 quads, minimum of one trip
* through unrolled loop. Do a quad at a time to get us 0mod64
* aligned.
*/
nop # E :
nop # E :
nop # E :
beq $1, $bigalign # U :
$alignmod64:
stq $17, 0($5) # L :
subq $3, 1, $3 # E : For consistency later
addq $1, 8, $1 # E : Increment towards zero for alignment
addq $5, 8, $4 # E : Initial wh64 address (filler instruction)
nop
nop
addq $5, 8, $5 # E : Inc address
blt $1, $alignmod64 # U :
$bigalign:
/*
* $3 - number quads left to go
* $5 - target address (aligned 0mod64)
* $17 - mask of stuff to store
* Scratch registers available: $7, $2, $4, $1
* we know that we'll be taking a minimum of one trip through
* CWG Section 3.7.6: do not expect a sustained store rate of > 1/cycle
* Assumes the wh64 needs to be for 2 trips through the loop in the future
* The wh64 is issued on for the starting destination address for trip +2
* through the loop, and if there are less than two trips left, the target
* address will be for the current trip.
*/
$do_wh64:
wh64 ($4) # L1 : memory subsystem write hint
subq $3, 24, $2 # E : For determining future wh64 addresses
stq $17, 0($5) # L :
nop # E :
addq $5, 128, $4 # E : speculative target of next wh64
stq $17, 8($5) # L :
stq $17, 16($5) # L :
addq $5, 64, $7 # E : Fallback address for wh64 (== next trip addr)
stq $17, 24($5) # L :
stq $17, 32($5) # L :
cmovlt $2, $7, $4 # E : Latency 2, extra mapping cycle
nop
stq $17, 40($5) # L :
stq $17, 48($5) # L :
subq $3, 16, $2 # E : Repeat the loop at least once more?
nop
stq $17, 56($5) # L :
addq $5, 64, $5 # E :
subq $3, 8, $3 # E :
bge $2, $do_wh64 # U :
nop
nop
nop
beq $3, no_quad # U : Might have finished already
.align 4
/*
* Simple loop for trailing quadwords, or for small amounts
* of data (where we can't use an unrolled loop and wh64)
*/
loop:
stq $17,0($5) # L :
subq $3,1,$3 # E : Decrement number quads left
addq $5,8,$5 # E : Inc address
bne $3,loop # U : more?
no_quad:
/*
* Write 0..7 trailing bytes.
*/
nop # E :
beq $18,end # U : All done?
ldq $7,0($5) # L :
mskqh $7,$6,$2 # U : Mask final quad
insqh $17,$6,$4 # U : New bits
bis $2,$4,$1 # E : Put it all together
stq $1,0($5) # L : And back to memory
ret $31,($26),1 # L0 :
within_one_quad:
ldq_u $1,0($16) # L :
insql $17,$16,$2 # U : New bits
mskql $1,$16,$4 # U : Clear old
bis $2,$4,$2 # E : New result
mskql $2,$6,$4 # U :
mskqh $1,$6,$2 # U :
bis $2,$4,$1 # E :
stq_u $1,0($16) # L :
end:
nop
nop
nop
ret $31,($26),1 # L0 :
.end __constant_c_memset
EXPORT_SYMBOL(__constant_c_memset)
/*
* This is a replicant of the __constant_c_memset code, rescheduled
* to mask stalls. Note that entry point names also had to change
*/
.align 5
.ent __memset16
__memset16:
.frame $30,0,$26,0
.prologue 0
inswl $17,0,$5 # U : 000000000000c1c2
inswl $17,2,$2 # U : 00000000c1c20000
bis $16,$16,$0 # E : return value
addq $18,$16,$6 # E : max address to write to
ble $18, end_w # U : zero length requested?
inswl $17,4,$3 # U : 0000c1c200000000
inswl $17,6,$4 # U : c1c2000000000000
xor $16,$6,$1 # E : will complete write be within one quadword?
or $2,$5,$2 # E : 00000000c1c2c1c2
or $3,$4,$17 # E : c1c2c1c200000000
bic $1,7,$1 # E : fit within a single quadword
and $16,7,$3 # E : Target addr misalignment
or $17,$2,$17 # E : c1c2c1c2c1c2c1c2
beq $1,within_quad_w # U :
nop
beq $3,aligned_w # U : target is 0mod8
/*
* Target address is misaligned, and won't fit within a quadword
*/
ldq_u $4,0($16) # L : Fetch first partial
bis $16,$16,$5 # E : Save the address
insql $17,$16,$2 # U : Insert new bytes
subq $3,8,$3 # E : Invert (for addressing uses)
addq $18,$3,$18 # E : $18 is new count ($3 is negative)
mskql $4,$16,$4 # U : clear relevant parts of the quad
subq $16,$3,$16 # E : $16 is new aligned destination
bis $2,$4,$1 # E : Final bytes
nop
stq_u $1,0($5) # L : Store result
nop
nop
.align 4
aligned_w:
/*
* We are now guaranteed to be quad aligned, with at least
* one partial quad to write.
*/
sra $18,3,$3 # U : Number of remaining quads to write
and $18,7,$18 # E : Number of trailing bytes to write
bis $16,$16,$5 # E : Save dest address
beq $3,no_quad_w # U : tail stuff only
/*
* it's worth the effort to unroll this and use wh64 if possible
* Lifted a bunch of code from clear_user.S
* At this point, entry values are:
* $16 Current destination address
* $5 A copy of $16
* $6 The max quadword address to write to
* $18 Number trailer bytes
* $3 Number quads to write
*/
and $16, 0x3f, $2 # E : Forward work (only useful for unrolled loop)
subq $3, 16, $4 # E : Only try to unroll if > 128 bytes
subq $2, 0x40, $1 # E : bias counter (aligning stuff 0mod64)
blt $4, loop_w # U :
/*
* We know we've got at least 16 quads, minimum of one trip
* through unrolled loop. Do a quad at a time to get us 0mod64
* aligned.
*/
nop # E :
nop # E :
nop # E :
beq $1, $bigalign_w # U :
$alignmod64_w:
stq $17, 0($5) # L :
subq $3, 1, $3 # E : For consistency later
addq $1, 8, $1 # E : Increment towards zero for alignment
addq $5, 8, $4 # E : Initial wh64 address (filler instruction)
nop
nop
addq $5, 8, $5 # E : Inc address
blt $1, $alignmod64_w # U :
$bigalign_w:
/*
* $3 - number quads left to go
* $5 - target address (aligned 0mod64)
* $17 - mask of stuff to store
* Scratch registers available: $7, $2, $4, $1
* we know that we'll be taking a minimum of one trip through
* CWG Section 3.7.6: do not expect a sustained store rate of > 1/cycle
* Assumes the wh64 needs to be for 2 trips through the loop in the future
* The wh64 is issued on for the starting destination address for trip +2
* through the loop, and if there are less than two trips left, the target
* address will be for the current trip.
*/
$do_wh64_w:
wh64 ($4) # L1 : memory subsystem write hint
subq $3, 24, $2 # E : For determining future wh64 addresses
stq $17, 0($5) # L :
nop # E :
addq $5, 128, $4 # E : speculative target of next wh64
stq $17, 8($5) # L :
stq $17, 16($5) # L :
addq $5, 64, $7 # E : Fallback address for wh64 (== next trip addr)
stq $17, 24($5) # L :
stq $17, 32($5) # L :
cmovlt $2, $7, $4 # E : Latency 2, extra mapping cycle
nop
stq $17, 40($5) # L :
stq $17, 48($5) # L :
subq $3, 16, $2 # E : Repeat the loop at least once more?
nop
stq $17, 56($5) # L :
addq $5, 64, $5 # E :
subq $3, 8, $3 # E :
bge $2, $do_wh64_w # U :
nop
nop
nop
beq $3, no_quad_w # U : Might have finished already
.align 4
/*
* Simple loop for trailing quadwords, or for small amounts
* of data (where we can't use an unrolled loop and wh64)
*/
loop_w:
stq $17,0($5) # L :
subq $3,1,$3 # E : Decrement number quads left
addq $5,8,$5 # E : Inc address
bne $3,loop_w # U : more?
no_quad_w:
/*
* Write 0..7 trailing bytes.
*/
nop # E :
beq $18,end_w # U : All done?
ldq $7,0($5) # L :
mskqh $7,$6,$2 # U : Mask final quad
insqh $17,$6,$4 # U : New bits
bis $2,$4,$1 # E : Put it all together
stq $1,0($5) # L : And back to memory
ret $31,($26),1 # L0 :
within_quad_w:
ldq_u $1,0($16) # L :
insql $17,$16,$2 # U : New bits
mskql $1,$16,$4 # U : Clear old
bis $2,$4,$2 # E : New result
mskql $2,$6,$4 # U :
mskqh $1,$6,$2 # U :
bis $2,$4,$1 # E :
stq_u $1,0($16) # L :
end_w:
nop
nop
nop
ret $31,($26),1 # L0 :
.end __memset16
EXPORT_SYMBOL(__memset16)
memset = ___memset
__memset = ___memset
EXPORT_SYMBOL(memset)
EXPORT_SYMBOL(__memset)