* [PATCH] 2.5.39 s390 (13/26): preemption.
@ 2002-09-30 12:56 Martin Schwidefsky
0 siblings, 0 replies; only message in thread
From: Martin Schwidefsky @ 2002-09-30 12:56 UTC (permalink / raw)
To: linux-kernel, torvalds
Add support for kernel preemption on s390/s390x.
diff -urN linux-2.5.39/arch/s390/config.in linux-2.5.39-s390/arch/s390/config.in
--- linux-2.5.39/arch/s390/config.in Mon Sep 30 13:25:48 2002
+++ linux-2.5.39-s390/arch/s390/config.in Mon Sep 30 13:32:33 2002
@@ -30,6 +30,7 @@
fi
comment 'Misc'
+bool 'Preemptible Kernel' CONFIG_PREEMPT
bool 'Builtin IPL record support' CONFIG_IPL
if [ "$CONFIG_IPL" = "y" ]; then
choice 'IPL method generated into head.S' \
diff -urN linux-2.5.39/arch/s390/defconfig linux-2.5.39-s390/arch/s390/defconfig
--- linux-2.5.39/arch/s390/defconfig Mon Sep 30 13:25:48 2002
+++ linux-2.5.39-s390/arch/s390/defconfig Mon Sep 30 13:32:33 2002
@@ -50,6 +50,7 @@
#
# Misc
#
+# CONFIG_PREEMPT is not set
CONFIG_IPL=y
# CONFIG_IPL_TAPE is not set
CONFIG_IPL_VM=y
diff -urN linux-2.5.39/arch/s390/kernel/entry.S linux-2.5.39-s390/arch/s390/kernel/entry.S
--- linux-2.5.39/arch/s390/kernel/entry.S Mon Sep 30 13:25:30 2002
+++ linux-2.5.39-s390/arch/s390/kernel/entry.S Mon Sep 30 13:32:33 2002
@@ -49,7 +49,7 @@
SP_TRAP = (SP_ORIG_R2+GPR_SIZE)
SP_SIZE = (SP_TRAP+4)
-_TIF_WORK_MASK = (_TIF_NOTIFY_RESUME | _TIF_SIGPENDING | _TIF_NEED_RESCHED)
+_TIF_WORK_MASK = (_TIF_SIGPENDING | _TIF_NEED_RESCHED)
/*
* Base Address of this Module --- saved in __LC_ENTRY_BASE
@@ -199,33 +199,44 @@
RESTORE_ALL 1
#
-# One of the work bits _TIF_NOTIFY_RESUME, _TIF_SIGPENDING or
-# _TIF_NEED_RESCHED is on. Find out which one.
+# recheck if there is more work to do
+#
+sysc_work_loop:
+ stnsm 24(%r15),0xfc # disable I/O and ext. interrupts
+ GET_THREAD_INFO # load pointer to task_struct to R9
+ tm __TI_flags+3(%r9),_TIF_WORK_MASK
+ bz BASED(sysc_leave) # there is no work to do
+#
+# One of the work bits is on. Find out which one.
+# Checked are: _TIF_SIGPENDING and _TIF_NEED_RESCHED
#
sysc_work:
- tm SP_PSW+1(%r15),0x01 # returning to user ?
- bno BASED(sysc_leave) # no-> skip resched & signal
tm __TI_flags+3(%r9),_TIF_NEED_RESCHED
bo BASED(sysc_reschedule)
- # add a test for TIF_NOTIFY_RESUME here when it is used.
- # _TIF_SIGPENDING is the only flag left
-#
-# call do_signal before return
-#
-sysc_signal_return:
- la %r2,SP_PTREGS(%r15) # load pt_regs
- sr %r3,%r3 # clear *oldset
- l %r1,BASED(.Ldo_signal)
- la %r14,BASED(sysc_return)
- br %r1 # return point is sysc_return
+ tm __TI_flags+3(%r9),_TIF_SIGPENDING
+ bo BASED(sysc_sigpending)
+ b BASED(sysc_leave)
#
-# call schedule with sysc_return as return-address
-#
+# _TIF_NEED_RESCHED is set, call schedule
+#
sysc_reschedule:
+ stosm 24(%r15),0x03 # reenable interrupts
l %r1,BASED(.Lschedule)
- la %r14,BASED(sysc_return)
- br %r1 # call scheduler, return to sysc_return
+ la %r14,BASED(sysc_work_loop)
+ br %r1 # call scheduler
+
+#
+# _TIF_SIGPENDING is set, call do_signal
+#
+sysc_sigpending:
+ stosm 24(%r15),0x03 # reenable interrupts
+ la %r2,SP_PTREGS(%r15) # load pt_regs
+ sr %r3,%r3 # clear *oldset
+ l %r1,BASED(.Ldo_signal)
+ basr %r14,%r1 # call do_signal
+ stnsm 24(%r15),0xfc # disable I/O and ext. interrupts
+ b BASED(sysc_leave) # out of here, do NOT recheck
#
# call trace before and after sys_call
@@ -258,9 +269,7 @@
basr %r13,0
l %r13,.Lentry_base-.(%r13) # setup base pointer to &entry_base
GET_THREAD_INFO # load pointer to task_struct to R9
- sr %r0,%r0 # child returns 0
- st %r0,SP_R2(%r15) # store return value (change R2 on stack)
-#ifdef CONFIG_SMP
+#if CONFIG_SMP || CONFIG_PREEMPT
l %r1,BASED(.Lschedtail)
la %r14,BASED(sysc_return)
br %r1 # call schedule_tail, return to sysc_return
@@ -616,13 +625,15 @@
tm __LC_PGM_INT_CODE+1,0x80 # check whether we got a per exception
bnz BASED(pgm_per) # got per exception -> special case
SAVE_ALL __LC_PGM_OLD_PSW,1
+ la %r8,0x7f
+ l %r3,__LC_PGM_ILC # load program interruption code
l %r7,BASED(.Ljump_table)
- lh %r8,__LC_PGM_INT_CODE
+ nr %r8,%r3
sll %r8,2
GET_THREAD_INFO
+ stosm 24(%r15),0x03 # reenable interrupts
l %r7,0(%r8,%r7) # load address of handler routine
la %r2,SP_PTREGS(%r15) # address of register-save area
- l %r3,__LC_PGM_ILC # load program interruption code
la %r14,BASED(sysc_return)
br %r7 # branch to interrupt-handler
@@ -647,6 +658,7 @@
GET_THREAD_INFO
la %r4,0x7f
l %r3,__LC_PGM_ILC # load program interruption code
+ stosm 24(%r15),0x03 # reenable interrupts
nr %r4,%r3 # clear per-event-bit and ilc
be BASED(pgm_per_only) # only per or per+check ?
l %r1,BASED(.Ljump_table)
@@ -666,9 +678,9 @@
pgm_svcper:
SAVE_ALL __LC_SVC_OLD_PSW,1
GET_THREAD_INFO # load pointer to task_struct to R9
+ stosm 24(%r15),0x03 # reenable interrupts
lh %r8,0x8a # get svc number from lowcore
sll %r8,2
- stosm 24(%r15),0x03 # reenable interrupts
l %r8,sys_call_table-entry_base(%r8,%r13) # get system call addr.
tm __TI_flags+3(%r9),_TIF_SYSCALL_TRACE
bo BASED(pgm_tracesys)
@@ -732,59 +744,81 @@
basr %r14,%r1 # branch to standard irq handler
io_return:
-#
-# check, if bottom-half has to be done
-#
- l %r1,__TI_cpu(%r9)
- sll %r1,L1_CACHE_SHIFT
- al %r1,BASED(.Lirq_stat) # get address of irq_stat
- icm %r0,15,0(%r1) # test irq_stat[#cpu].__softirq_pending
- bnz BASED(io_handle_bottom_half)
-io_return_bh:
+ tm SP_PSW+1(%r15),0x01 # returning to user ?
+#ifdef CONFIG_PREEMPT
+ bno BASED(io_preempt) # no -> check for preemptive scheduling
+#else
+ bno BASED(io_leave) # no-> skip resched & signal
+#endif
tm __TI_flags+3(%r9),_TIF_WORK_MASK
bnz BASED(io_work) # there is work to do (signals etc.)
io_leave:
- stnsm 24(%r15),0xfc # disable I/O and ext. interrupts
RESTORE_ALL 0
+#ifdef CONFIG_PREEMPT
+io_preempt:
+ icm %r0,15,__TI_precount(%r9)
+ bnz BASED(io_leave)
+io_resume_loop:
+ tm __TI_flags+3(%r9),_TIF_NEED_RESCHED
+ bno BASED(io_leave)
+ mvc __TI_precount(4,%r9),.Lc_pactive
+ # hmpf, we are on the async. stack but to call schedule
+ # we have to move the interrupt frame to the process stack
+ l %r1,SP_R15(%r15)
+ s %r1,BASED(.Lc_spsize)
+ n %r1,BASED(.Lc0xfffffff8)
+ mvc SP_PTREGS(SP_SIZE-SP_PTREGS,%r1),SP_PTREGS(%r15)
+ xc 0(4,%r1),0(%r1) # clear back chain
+ lr %r15,%r1
+ stosm 24(%r15),0x03 # reenable interrupts
+ l %r1,BASED(.Lschedule)
+ basr %r14,%r1 # call schedule
+ stnsm 24(%r15),0xfc # disable I/O and ext. interrupts
+ GET_THREAD_INFO # load pointer to task_struct to R9
+ xc __TI_precount(4,%r9),__TI_precount(%r9)
+ b BASED(io_resume_loop)
+#endif
+
#
-# call do_softirq
+# recheck if there is more work to do
#
-io_handle_bottom_half:
- l %r1,BASED(.Ldo_softirq)
- la %r14,BASED(io_return_bh)
- br %r1 # call do_softirq
-
+io_work_loop:
+ stnsm 24(%r15),0xfc # disable I/O and ext. interrupts
+ GET_THREAD_INFO # load pointer to task_struct to R9
+ tm __TI_flags+3(%r9),_TIF_WORK_MASK
+ bz BASED(io_leave) # there is no work to do
#
-# One of the work bits _TIF_NOTIFY_RESUME, _TIF_SIGPENDING or
-# _TIF_NEED_RESCHED is on. Find out which one.
+# One of the work bits is on. Find out which one.
+# Checked are: _TIF_SIGPENDING and _TIF_NEED_RESCHED
#
io_work:
- tm SP_PSW+1(%r15),0x01 # returning to user ?
- bno BASED(io_leave) # no-> skip resched & signal
- stosm 24(%r15),0x03 # reenable interrupts
tm __TI_flags+3(%r9),_TIF_NEED_RESCHED
bo BASED(io_reschedule)
- # add a test for TIF_NOTIFY_RESUME here when it is used.
- # _TIF_SIGPENDING is the only flag left
+ tm __TI_flags+3(%r9),_TIF_SIGPENDING
+ bo BASED(io_sigpending)
+ b BASED(io_leave)
#
-# call do_signal before return
-#
-io_signal_return:
- la %r2,SP_PTREGS(%r15) # load pt_regs
- sr %r3,%r3 # clear *oldset
- l %r1,BASED(.Ldo_signal)
- la %r14,BASED(io_leave)
- br %r1 # return point is io_leave
+# _TIF_NEED_RESCHED is set, call schedule
+#
+io_reschedule:
+ stosm 24(%r15),0x03 # reenable interrupts
+ l %r1,BASED(.Lschedule)
+ la %r14,BASED(io_work_loop)
+ br %r1 # call scheduler
#
-# call schedule with io_return as return-address
+# _TIF_SIGPENDING is set, call do_signal
#
-io_reschedule:
- l %r1,BASED(.Lschedule)
- la %r14,BASED(io_return)
- br %r1 # call scheduler, return to io_return
+io_sigpending:
+ stosm 24(%r15),0x03 # reenable interrupts
+ la %r2,SP_PTREGS(%r15) # load pt_regs
+ sr %r3,%r3 # clear *oldset
+ l %r1,BASED(.Ldo_signal)
+ basr %r14,%r1 # call do_signal
+ stnsm 24(%r15),0xfc # disable I/O and ext. interrupts
+ b BASED(io_leave) # out of here, do NOT recheck
/*
* External interrupt handler routine
@@ -865,19 +899,12 @@
.align 4
.Lc0xfffffff8: .long -8 # to align stack pointer to 8
.Lc0xffffe000: .long -8192 # to round stack pointer to &task_struct
-.Lc8191: .long 8191
.Lc_spsize: .long SP_SIZE
.Lc_overhead: .long STACK_FRAME_OVERHEAD
.Lc_ac: .long 0,0,1
.Lc_ENOSYS: .long -ENOSYS
-.Lc4: .long 4
-.Lc20: .long 20
-.Lc0x1202: .long 0x1202
-.Lc0x1004: .long 0x1004
-.Lc0x2401: .long 0x2401
-.Lc0x4000: .long 0x4000
+.Lc_pactive: .long PREEMPT_ACTIVE
.Lc0xff: .long 0xff
-.Lc128: .long 128
.Lc256: .long 256
/*
@@ -890,7 +917,6 @@
.Lentry_base: .long entry_base
.Lext_hash: .long ext_int_hash
.Lhandle_per: .long handle_per_exception
-.Lirq_stat: .long irq_stat
.Ljump_table: .long pgm_check_table
.Lschedule: .long schedule
.Lclone: .long sys_clone
@@ -904,7 +930,7 @@
.Lsigaltstack: .long sys_sigaltstack
.Ltrace: .long syscall_trace
.Lvfork: .long sys_vfork
-#ifdef CONFIG_SMP
+#if CONFIG_SMP || CONFIG_PREEMPT
.Lschedtail: .long schedule_tail
#endif
diff -urN linux-2.5.39/arch/s390x/config.in linux-2.5.39-s390/arch/s390x/config.in
--- linux-2.5.39/arch/s390x/config.in Mon Sep 30 13:25:48 2002
+++ linux-2.5.39-s390/arch/s390x/config.in Mon Sep 30 13:32:33 2002
@@ -33,6 +33,7 @@
fi
comment 'Misc'
+bool 'Preemptible Kernel' CONFIG_PREEMPT
bool 'Builtin IPL record support' CONFIG_IPL
if [ "$CONFIG_IPL" = "y" ]; then
choice 'IPL method generated into head.S' \
diff -urN linux-2.5.39/arch/s390x/defconfig linux-2.5.39-s390/arch/s390x/defconfig
--- linux-2.5.39/arch/s390x/defconfig Mon Sep 30 13:25:48 2002
+++ linux-2.5.39-s390/arch/s390x/defconfig Mon Sep 30 13:32:33 2002
@@ -51,6 +51,7 @@
#
# Misc
#
+# CONFIG_PREEMPT is not set
CONFIG_IPL=y
# CONFIG_IPL_TAPE is not set
CONFIG_IPL_VM=y
diff -urN linux-2.5.39/arch/s390x/kernel/entry.S linux-2.5.39-s390/arch/s390x/kernel/entry.S
--- linux-2.5.39/arch/s390x/kernel/entry.S Mon Sep 30 13:25:30 2002
+++ linux-2.5.39-s390/arch/s390x/kernel/entry.S Mon Sep 30 13:32:33 2002
@@ -49,7 +49,7 @@
SP_TRAP = (SP_ORIG_R2+GPR_SIZE)
SP_SIZE = (SP_TRAP+4)
-_TIF_WORK_MASK = (_TIF_NOTIFY_RESUME | _TIF_SIGPENDING | _TIF_NEED_RESCHED)
+_TIF_WORK_MASK = (_TIF_SIGPENDING | _TIF_NEED_RESCHED)
/*
* Register usage in interrupt handlers:
@@ -185,32 +185,42 @@
RESTORE_ALL 1
#
-# One of the work bits _TIF_NOTIFY_RESUME, _TIF_SIGPENDING or
-# _TIF_NEED_RESCHED is on. Find out which one.
+# recheck if there is more work to do
+#
+sysc_work_loop:
+ stnsm 48(%r15),0xfc # disable I/O and ext. interrupts
+ GET_THREAD_INFO # load pointer to task_struct to R9
+ tm __TI_flags+7(%r9),_TIF_WORK_MASK
+ jz sysc_leave # there is no work to do
+#
+# One of the work bits is on. Find out which one.
+# Checked are: _TIF_SIGPENDING and _TIF_NEED_RESCHED
#
sysc_work:
- tm SP_PSW+1(%r15),0x01 # returning to user ?
- jno sysc_leave # no-> skip resched & signal
tm __TI_flags+7(%r9),_TIF_NEED_RESCHED
jo sysc_reschedule
- # add a test for TIF_NOTIFY_RESUME here when it is used.
- # _TIF_SIGPENDING is the only flag left
+ tm __TI_flags+7(%r9),_TIF_SIGPENDING
+ jo sysc_sigpending
+ j sysc_leave
#
-# call do_signal before return
-#
-sysc_signal_return:
- la %r2,SP_PTREGS(%r15) # load pt_regs
- sgr %r3,%r3 # clear *oldset
- larl %r14,sysc_return
- jg do_signal # return point is sysc_return
+# _TIF_NEED_RESCHED is set, call schedule
+#
+sysc_reschedule:
+ stosm 48(%r15),0x03 # reenable interrupts
+ larl %r14,sysc_work_loop
+ jg schedule # return point is sysc_return
#
-# call schedule with sysc_return as return-address
+# _TIF_SIGPENDING is set, call do_signal
#
-sysc_reschedule:
- larl %r14,sysc_return
- jg schedule # return point is sysc_return
+sysc_sigpending:
+ stosm 48(%r15),0x03 # reenable interrupts
+ la %r2,SP_PTREGS(%r15) # load pt_regs
+ sgr %r3,%r3 # clear *oldset
+ brasl %r14,do_signal # call do_signal
+ stnsm 48(%r15),0xfc # disable I/O and ext. interrupts
+ j sysc_leave # out of here, do NOT recheck
#
# call syscall_trace before and after system call
@@ -242,8 +252,7 @@
.globl ret_from_fork
ret_from_fork:
GET_THREAD_INFO # load pointer to task_struct to R9
- xc SP_R2(8,%r15),SP_R2(%r15) # child returns 0
-#ifdef CONFIG_SMP
+#if CONFIG_SMP || CONFIG_PREEMPT
larl %r14,sysc_return
jg schedule_tail # return to sysc_return
#else
@@ -551,8 +560,8 @@
.long SYSCALL(sys_rt_sigtimedwait,sys32_rt_sigtimedwait_wrapper)
.long SYSCALL(sys_rt_sigqueueinfo,sys32_rt_sigqueueinfo_wrapper)
.long SYSCALL(sys_rt_sigsuspend_glue,sys32_rt_sigsuspend_glue)
- .long SYSCALL(sys_pread64,sys32_pread_wrapper) /* 180 */
- .long SYSCALL(sys_pwrite64,sys32_pwrite_wrapper)
+ .long SYSCALL(sys_pread64,sys32_pread64_wrapper) /* 180 */
+ .long SYSCALL(sys_pwrite64,sys32_pwrite64_wrapper)
.long SYSCALL(sys_ni_syscall,sys32_chown16_wrapper) /* old chown16 syscall */
.long SYSCALL(sys_getcwd,sys32_getcwd_wrapper)
.long SYSCALL(sys_capget,sys32_capget_wrapper)
@@ -646,13 +655,15 @@
tm __LC_PGM_INT_CODE+1,0x80 # check whether we got a per exception
jnz pgm_per # got per exception -> special case
SAVE_ALL __LC_PGM_OLD_PSW,1
- llgh %r8,__LC_PGM_INT_CODE
+ lghi %r8,0x7f
+ lgf %r3,__LC_PGM_ILC # load program interruption code
+ ngr %r8,%r3
sll %r8,3
GET_THREAD_INFO
+ stosm 48(%r15),0x03 # reenable interrupts
larl %r1,pgm_check_table
lg %r1,0(%r8,%r1) # load address of handler routine
la %r2,SP_PTREGS(%r15) # address of register-save area
- lgf %r3,__LC_PGM_ILC # load program interruption code
larl %r14,sysc_return
br %r1 # branch to interrupt-handler
@@ -676,6 +687,7 @@
GET_THREAD_INFO
lghi %r4,0x7f
lgf %r3,__LC_PGM_ILC # load program interruption code
+ stosm 48(%r15),0x03 # reenable interrupts
nr %r4,%r3 # clear per-event-bit and ilc
je pgm_per_only # only per of per+check ?
sll %r4,3
@@ -759,57 +771,79 @@
brasl %r14,do_IRQ # call standard irq handler
io_return:
-#
-# check, if bottom-half has to be done
-#
- lgf %r1,__TI_cpu(%r9)
- larl %r2,irq_stat
- sll %r1,L1_CACHE_SHIFT
- la %r1,0(%r1,%r2)
- icm %r0,15,0(%r1) # test irq_stat[#cpu].__softirq_pending
- jnz io_handle_bottom_half
-io_return_bh:
+ tm SP_PSW+1(%r15),0x01 # returning to user ?
+#ifdef CONFIG_PREEMPT
+ jno io_preempt # no -> check for preemptive scheduling
+#else
+ jno io_leave # no-> skip resched & signal
+#endif
tm __TI_flags+7(%r9),_TIF_WORK_MASK
jnz io_work # there is work to do (signals etc.)
io_leave:
- stnsm 48(%r15),0xfc # disable I/O and ext. interrupts
RESTORE_ALL 0
+#ifdef CONFIG_PREEMPT
+io_preempt:
+ icm %r0,15,__TI_precount(%r9)
+ jnz io_leave
+io_resume_loop:
+ tm __TI_flags+7(%r9),_TIF_NEED_RESCHED
+ jno io_leave
+ larl %r1,.Lc_pactive
+ mvc __TI_precount(4,%r9),0(%r1)
+ # hmpf, we are on the async. stack but to call schedule
+ # we have to move the interrupt frame to the process stack
+ lg %r1,SP_R15(%r15)
+ aghi %r1,-SP_SIZE
+ nill %r1,0xfff8
+ mvc SP_PTREGS(SP_SIZE-SP_PTREGS,%r1),SP_PTREGS(%r15)
+ xc 0(8,%r1),0(%r1) # clear back chain
+ lgr %r15,%r1
+ stosm 48(%r15),0x03 # reenable interrupts
+ brasl %r14,schedule # call schedule
+ stnsm 48(%r15),0xfc # disable I/O and ext. interrupts
+ GET_THREAD_INFO # load pointer to task_struct to R9
+ xc __TI_precount(4,%r9),__TI_precount(%r9)
+ j io_resume_loop
+#endif
+
#
-# call do_softirq
+# recheck if there is more work to do
#
-io_handle_bottom_half:
- larl %r14,io_return_bh
- jg do_softirq # return point is io_return_bh
-
+io_work_loop:
+ stnsm 48(%r15),0xfc # disable I/O and ext. interrupts
+ GET_THREAD_INFO # load pointer to task_struct to R9
+ tm __TI_flags+7(%r9),_TIF_WORK_MASK
+ jz io_leave # there is no work to do
#
-# One of the work bits _TIF_NOTIFY_RESUME, _TIF_SIGPENDING or
-# _TIF_NEED_RESCHED is on. Find out which one.
+# One of the work bits is on. Find out which one.
+# Checked are: _TIF_SIGPENDING and _TIF_NEED_RESCHED
#
io_work:
- tm SP_PSW+1(%r15),0x01 # returning to user ?
- jno io_leave # no-> skip resched & signal
- stosm 48(%r15),0x03 # reenable interrupts
tm __TI_flags+7(%r9),_TIF_NEED_RESCHED
jo io_reschedule
- # add a test for TIF_NOTIFY_RESUME here when it is used.
- # _TIF_SIGPENDING is the only flag left
+ tm __TI_flags+7(%r9),_TIF_SIGPENDING
+ jo io_sigpending
+ j io_leave
#
-# call do_signal before return
-#
-io_signal_return:
- la %r2,SP_PTREGS(%r15) # load pt_regs
- slgr %r3,%r3 # clear *oldset
- larl %r14,io_leave
- jg do_signal # return point is io_leave
+# _TIF_NEED_RESCHED is set, call schedule
+#
+io_reschedule:
+ stosm 48(%r15),0x03 # reenable interrupts
+ larl %r14,io_work_loop
+ jg schedule # call scheduler
#
-# call schedule with io_return as return-address
+# _TIF_SIGPENDING is set, call do_signal
#
-io_reschedule:
- larl %r14,io_return
- jg schedule # call scheduler, return to io_return
+io_sigpending:
+ stosm 48(%r15),0x03 # reenable interrupts
+ la %r2,SP_PTREGS(%r15) # load pt_regs
+ slgr %r3,%r3 # clear *oldset
+ brasl %r14,do_signal # call do_signal
+ stnsm 48(%r15),0xfc # disable I/O and ext. interrupts
+ j sysc_leave # out of here, do NOT recheck
/*
* External interrupt handler routine
@@ -883,4 +917,5 @@
*/
.align 4
.Lc_ac: .long 0,0,1
+.Lc_pactive: .long PREEMPT_ACTIVE
.Lc256: .quad 256
diff -urN linux-2.5.39/include/asm-s390/hardirq.h linux-2.5.39-s390/include/asm-s390/hardirq.h
--- linux-2.5.39/include/asm-s390/hardirq.h Mon Sep 30 13:25:21 2002
+++ linux-2.5.39-s390/include/asm-s390/hardirq.h Mon Sep 30 13:32:33 2002
@@ -80,15 +80,21 @@
extern void do_call_softirq(void);
-#define in_atomic() (preempt_count() != 0)
-#define IRQ_EXIT_OFFSET HARDIRQ_OFFSET
+#if CONFIG_PREEMPT
+# define in_atomic() (in_interrupt() || preempt_count() == PREEMPT_ACTIVE)
+# define IRQ_EXIT_OFFSET (HARDIRQ_OFFSET-1)
+#else
+# define in_atomic() (preempt_count() != 0)
+# define IRQ_EXIT_OFFSET HARDIRQ_OFFSET
+#endif
#define irq_exit() \
do { \
- preempt_count() -= HARDIRQ_OFFSET; \
+ preempt_count() -= IRQ_EXIT_OFFSET; \
if (!in_interrupt() && softirq_pending(smp_processor_id())) \
/* Use the async. stack for softirq */ \
do_call_softirq(); \
+ preempt_enable_no_resched(); \
} while (0)
#ifndef CONFIG_SMP
diff -urN linux-2.5.39/include/asm-s390/softirq.h linux-2.5.39-s390/include/asm-s390/softirq.h
--- linux-2.5.39/include/asm-s390/softirq.h Mon Sep 30 13:25:21 2002
+++ linux-2.5.39-s390/include/asm-s390/softirq.h Mon Sep 30 13:32:33 2002
@@ -10,6 +10,7 @@
#define __ASM_SOFTIRQ_H
#include <linux/smp.h>
+#include <linux/preempt.h>
#include <asm/atomic.h>
#include <asm/hardirq.h>
@@ -28,6 +29,7 @@
if (!in_interrupt() && softirq_pending(smp_processor_id())) \
/* Use the async. stack for softirq */ \
do_call_softirq(); \
+ preempt_check_resched(); \
} while (0)
#endif /* __ASM_SOFTIRQ_H */
diff -urN linux-2.5.39/include/asm-s390/thread_info.h linux-2.5.39-s390/include/asm-s390/thread_info.h
--- linux-2.5.39/include/asm-s390/thread_info.h Fri Sep 27 23:50:23 2002
+++ linux-2.5.39-s390/include/asm-s390/thread_info.h Mon Sep 30 13:32:33 2002
@@ -25,11 +25,9 @@
struct exec_domain *exec_domain; /* execution domain */
unsigned long flags; /* low level flags */
unsigned int cpu; /* current CPU */
- int preempt_count; /* 0 => preemptable, <0 => BUG */
+ unsigned int preempt_count; /* 0 => preemptable */
};
-#define PREEMPT_ACTIVE 0x4000000
-
/*
* macros/functions for gaining access to the thread information structure
*/
@@ -84,4 +82,6 @@
#endif /* __KERNEL__ */
+#define PREEMPT_ACTIVE 0x4000000
+
#endif /* _ASM_THREAD_INFO_H */
diff -urN linux-2.5.39/include/asm-s390x/hardirq.h linux-2.5.39-s390/include/asm-s390x/hardirq.h
--- linux-2.5.39/include/asm-s390x/hardirq.h Mon Sep 30 13:25:21 2002
+++ linux-2.5.39-s390/include/asm-s390x/hardirq.h Mon Sep 30 13:32:33 2002
@@ -81,15 +81,21 @@
extern void do_call_softirq(void);
-#define in_atomic() (preempt_count() != 0)
-#define IRQ_EXIT_OFFSET HARDIRQ_OFFSET
+#if CONFIG_PREEMPT
+# define in_atomic() (in_interrupt() || preempt_count() == PREEMPT_ACTIVE)
+# define IRQ_EXIT_OFFSET (HARDIRQ_OFFSET-1)
+#else
+# define in_atomic() (preempt_count() != 0)
+# define IRQ_EXIT_OFFSET HARDIRQ_OFFSET
+#endif
#define irq_exit() \
do { \
- preempt_count() -= HARDIRQ_OFFSET; \
+ preempt_count() -= IRQ_EXIT_OFFSET; \
if (!in_interrupt() && softirq_pending(smp_processor_id())) \
/* Use the async. stack for softirq */ \
do_call_softirq(); \
+ preempt_enable_no_resched(); \
} while (0)
#ifndef CONFIG_SMP
diff -urN linux-2.5.39/include/asm-s390x/thread_info.h linux-2.5.39-s390/include/asm-s390x/thread_info.h
--- linux-2.5.39/include/asm-s390x/thread_info.h Fri Sep 27 23:50:26 2002
+++ linux-2.5.39-s390/include/asm-s390x/thread_info.h Mon Sep 30 13:32:33 2002
@@ -25,11 +25,9 @@
struct exec_domain *exec_domain; /* execution domain */
unsigned long flags; /* low level flags */
unsigned int cpu; /* current CPU */
- int preempt_count; /* 0 => preemptable, <0 => BUG */
+ unsigned int preempt_count; /* 0 => preemptable */
};
-#define PREEMPT_ACTIVE 0x4000000
-
/*
* macros/functions for gaining access to the thread information structure
*/
@@ -84,4 +82,6 @@
#endif /* __KERNEL__ */
+#define PREEMPT_ACTIVE 0x4000000
+
#endif /* _ASM_THREAD_INFO_H */
^ permalink raw reply [flat|nested] only message in thread
only message in thread, other threads:[~2002-09-30 14:11 UTC | newest]
Thread overview: (only message) (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2002-09-30 12:56 [PATCH] 2.5.39 s390 (13/26): preemption Martin Schwidefsky
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).