Commit 987ad70a authored by Martin Schwidefsky's avatar Martin Schwidefsky

[S390] system call optimization.

After the in-kernel system call has been remove the system call path
can be optimized. The problem state bit of the old psw is always set
between system_call and sysc_do_svc. SAVE_ALL_SVC uses this information
to avoid two instructions.
Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
parent 3d62149f
......@@ -107,6 +107,11 @@ STACK_SIZE = 1 << STACK_SHIFT
l %r13,__LC_SVC_NEW_PSW+4 # load &system_call to %r13
.endm
.macro SAVE_ALL_SVC psworg,savearea
la %r12,\psworg
l %r15,__LC_KERNEL_STACK # problem state -> load ksp
.endm
.macro SAVE_ALL_SYNC psworg,savearea
la %r12,\psworg
tm \psworg+1,0x01 # test problem state bit
......@@ -218,7 +223,7 @@ system_call:
STORE_TIMER __LC_SYNC_ENTER_TIMER
sysc_saveall:
SAVE_ALL_BASE __LC_SAVE_AREA
SAVE_ALL_SYNC __LC_SVC_OLD_PSW,__LC_SAVE_AREA
SAVE_ALL_SVC __LC_SVC_OLD_PSW,__LC_SAVE_AREA
CREATE_STACK_FRAME __LC_SVC_OLD_PSW,__LC_SAVE_AREA
lh %r7,0x8a # get svc number from lowcore
#ifdef CONFIG_VIRT_CPU_ACCOUNTING
......
......@@ -99,6 +99,11 @@ _TIF_WORK_INT = (_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK | _TIF_NEED_RESCHED | \
larl %r13,system_call
.endm
.macro SAVE_ALL_SVC psworg,savearea
la %r12,\psworg
lg %r15,__LC_KERNEL_STACK # problem state -> load ksp
.endm
.macro SAVE_ALL_SYNC psworg,savearea
la %r12,\psworg
tm \psworg+1,0x01 # test problem state bit
......@@ -207,7 +212,7 @@ system_call:
STORE_TIMER __LC_SYNC_ENTER_TIMER
sysc_saveall:
SAVE_ALL_BASE __LC_SAVE_AREA
SAVE_ALL_SYNC __LC_SVC_OLD_PSW,__LC_SAVE_AREA
SAVE_ALL_SVC __LC_SVC_OLD_PSW,__LC_SAVE_AREA
CREATE_STACK_FRAME __LC_SVC_OLD_PSW,__LC_SAVE_AREA
llgh %r7,__LC_SVC_INT_CODE # get svc number from lowcore
#ifdef CONFIG_VIRT_CPU_ACCOUNTING
......
Markdown is supported
0% or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment