提交 a2eddc7c 编写于 作者: D David Howells 提交者: Al Viro

FRV: Optimise the system call exit path in entry.S [ver #2]

Optimise the system call exit path in entry.S by packing some instructions.
Suggested-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
上级 1e5ef915
......@@ -905,18 +905,19 @@ __syscall_call:
__syscall_exit:
LEDS 0x6300
sti gr8,@(gr28,#REG_GR(8)) ; save return value
# keep current PSR in GR23
movsg psr,gr23
# rebuild saved psr - execve will change it for init/main.c
ldi @(gr28,#REG_PSR),gr22
sti.p gr8,@(gr28,#REG_GR(8)) ; save return value
# rebuild saved psr - execve will change it for init/main.c
srli gr22,#1,gr5
andi.p gr22,#~PSR_PS,gr22
andi gr5,#PSR_PS,gr5
or gr5,gr22,gr22
ori gr22,#PSR_S,gr22
# keep current PSR in GR23
movsg psr,gr23
ori.p gr22,#PSR_S,gr22
# make sure we don't miss an interrupt setting need_resched or sigpending between
# sampling and the RETT
......
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