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| author | Heiko Carstens <hca@linux.ibm.com> | 2024-09-19 14:40:10 +0200 |
|---|---|---|
| committer | Vasily Gorbik <gor@linux.ibm.com> | 2024-09-23 17:57:04 +0200 |
| commit | d714abee5fb64c4817dce477bd7f2bd1bb4fe814 (patch) | |
| tree | 4c7918ca2e019d145f80a862caf0b585d4ff7eea /arch/s390 | |
| parent | c902b578eebfe0739e8ec491b60f2f37dfeb09c0 (diff) | |
| download | lwn-d714abee5fb64c4817dce477bd7f2bd1bb4fe814.tar.gz lwn-d714abee5fb64c4817dce477bd7f2bd1bb4fe814.zip | |
s390/vdso: Use one large alternative instead of an alternative branch
Replace the alternative branch with a larger alternative that contains
both paths. That way the two paths are closer together and it is easier
to change both paths if the need should arise.
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Reviewed-by: Jens Remus <jremus@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Diffstat (limited to 'arch/s390')
| -rw-r--r-- | arch/s390/kernel/vdso64/vgetrandom-chacha.S | 35 |
1 files changed, 16 insertions, 19 deletions
diff --git a/arch/s390/kernel/vdso64/vgetrandom-chacha.S b/arch/s390/kernel/vdso64/vgetrandom-chacha.S index 4c52ba78e060..09c034c2f853 100644 --- a/arch/s390/kernel/vdso64/vgetrandom-chacha.S +++ b/arch/s390/kernel/vdso64/vgetrandom-chacha.S @@ -130,16 +130,22 @@ SYM_FUNC_START(__arch_chacha20_blocks_nostack) /* OUTPUT3 = STATE3 + COPY3 */ VAF STATE3,STATE3,COPY3 - /* - * 32 bit wise little endian store to OUTPUT. If the vector - * enhancement facility 2 is not installed use the slow path. - */ - ALTERNATIVE "brc 0xf,.Lstoreslow", "nop", ALT_FACILITY(148) - VSTBRF STATE0,0,,%r2 - VSTBRF STATE1,16,,%r2 - VSTBRF STATE2,32,,%r2 - VSTBRF STATE3,48,,%r2 -.Lstoredone: + ALTERNATIVE \ + __stringify( \ + /* Convert STATE to little endian and store to OUTPUT */\ + VPERM TMP0,STATE0,STATE0,BEPERM; \ + VPERM TMP1,STATE1,STATE1,BEPERM; \ + VPERM TMP2,STATE2,STATE2,BEPERM; \ + VPERM TMP3,STATE3,STATE3,BEPERM; \ + VSTM TMP0,TMP3,0,%r2), \ + __stringify( \ + /* 32 bit wise little endian store to OUTPUT */ \ + VSTBRF STATE0,0,,%r2; \ + VSTBRF STATE1,16,,%r2; \ + VSTBRF STATE2,32,,%r2; \ + VSTBRF STATE3,48,,%r2; \ + brcl 0,0), \ + ALT_FACILITY(148) /* ++COPY3.COUNTER */ /* alsih %r3,1 */ @@ -171,14 +177,5 @@ SYM_FUNC_START(__arch_chacha20_blocks_nostack) VZERO TMP3 br %r14 - -.Lstoreslow: - /* Convert STATE to little endian format and store to OUTPUT */ - VPERM TMP0,STATE0,STATE0,BEPERM - VPERM TMP1,STATE1,STATE1,BEPERM - VPERM TMP2,STATE2,STATE2,BEPERM - VPERM TMP3,STATE3,STATE3,BEPERM - VSTM TMP0,TMP3,0,%r2 - j .Lstoredone CFI_ENDPROC SYM_FUNC_END(__arch_chacha20_blocks_nostack) |