From: Martin Schwidefsky Date: Tue, 10 Jul 2007 09:24:18 +0000 (+0200) Subject: [S390] system call optimization. X-Git-Tag: v2.6.23-rc1~1155^2~4 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=987ad70a4d90cf0e70dba43ece02c2e2219e092c;p=linux-2.6 [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: Martin Schwidefsky --- diff --git a/arch/s390/kernel/entry.S b/arch/s390/kernel/entry.S index 6234c6978a..bc7ff3658c 100644 --- a/arch/s390/kernel/entry.S +++ b/arch/s390/kernel/entry.S @@ -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 diff --git a/arch/s390/kernel/entry64.S b/arch/s390/kernel/entry64.S index 685f11faa4..2a7b130441 100644 --- a/arch/s390/kernel/entry64.S +++ b/arch/s390/kernel/entry64.S @@ -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