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Commit b2a749f0 authored by Martin Schwidefsky's avatar Martin Schwidefsky Committed by Linus Torvalds
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[PATCH] s390 update (13/27): preemption support. 

Add support for kernel preemption on s390/s390x.
parent 6e701a16
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Showing with 221 additions and 142 deletions
arch/s390/config.in
View file @ b2a749f0
...@@ -30,6 +30,7 @@ if [ "$CONFIG_QDIO" != "n" ]; then ...@@ -30,6 +30,7 @@ if [ "$CONFIG_QDIO" != "n" ]; then
fi fi
comment 'Misc' comment 'Misc'
bool 'Preemptible Kernel' CONFIG_PREEMPT
bool 'Builtin IPL record support' CONFIG_IPL bool 'Builtin IPL record support' CONFIG_IPL
if [ "$CONFIG_IPL" = "y" ]; then if [ "$CONFIG_IPL" = "y" ]; then
choice 'IPL method generated into head.S' \ choice 'IPL method generated into head.S' \
......
arch/s390/defconfig
View file @ b2a749f0
...@@ -50,6 +50,7 @@ CONFIG_QDIO=m ...@@ -50,6 +50,7 @@ CONFIG_QDIO=m
# #
# Misc # Misc
# #
# CONFIG_PREEMPT is not set
CONFIG_IPL=y CONFIG_IPL=y
# CONFIG_IPL_TAPE is not set # CONFIG_IPL_TAPE is not set
CONFIG_IPL_VM=y CONFIG_IPL_VM=y
......
arch/s390/kernel/entry.S
View file @ b2a749f0
...@@ -48,7 +48,7 @@ SP_ORIG_R2 = STACK_FRAME_OVERHEAD + PT_ORIGGPR2 ...@@ -48,7 +48,7 @@ SP_ORIG_R2 = STACK_FRAME_OVERHEAD + PT_ORIGGPR2
SP_TRAP = (SP_ORIG_R2+GPR_SIZE) SP_TRAP = (SP_ORIG_R2+GPR_SIZE)
SP_SIZE = (SP_TRAP+4) 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 * Base Address of this Module --- saved in __LC_ENTRY_BASE
...@@ -198,33 +198,44 @@ sysc_leave: ...@@ -198,33 +198,44 @@ sysc_leave:
RESTORE_ALL 1 RESTORE_ALL 1
# #
# One of the work bits _TIF_NOTIFY_RESUME, _TIF_SIGPENDING or # recheck if there is more work to do
# _TIF_NEED_RESCHED is on. Find out which one. #
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: 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 tm __TI_flags+3(%r9),_TIF_NEED_RESCHED
bo BASED(sysc_reschedule) bo BASED(sysc_reschedule)
# add a test for TIF_NOTIFY_RESUME here when it is used. tm __TI_flags+3(%r9),_TIF_SIGPENDING
# _TIF_SIGPENDING is the only flag left bo BASED(sysc_sigpending)
# b BASED(sysc_leave)
# 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
# #
# call schedule with sysc_return as return-address # _TIF_NEED_RESCHED is set, call schedule
# #
sysc_reschedule: sysc_reschedule:
stosm 24(%r15),0x03 # reenable interrupts
l %r1,BASED(.Lschedule) l %r1,BASED(.Lschedule)
la %r14,BASED(sysc_return) la %r14,BASED(sysc_work_loop)
br %r1 # call scheduler, return to sysc_return 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 # call trace before and after sys_call
...@@ -257,9 +268,7 @@ ret_from_fork: ...@@ -257,9 +268,7 @@ ret_from_fork:
basr %r13,0 basr %r13,0
l %r13,.Lentry_base-.(%r13) # setup base pointer to &entry_base l %r13,.Lentry_base-.(%r13) # setup base pointer to &entry_base
GET_THREAD_INFO # load pointer to task_struct to R9 GET_THREAD_INFO # load pointer to task_struct to R9
sr %r0,%r0 # child returns 0 #if CONFIG_SMP || CONFIG_PREEMPT
st %r0,SP_R2(%r15) # store return value (change R2 on stack)
#ifdef CONFIG_SMP
l %r1,BASED(.Lschedtail) l %r1,BASED(.Lschedtail)
la %r14,BASED(sysc_return) la %r14,BASED(sysc_return)
br %r1 # call schedule_tail, return to sysc_return br %r1 # call schedule_tail, return to sysc_return
...@@ -615,13 +624,15 @@ pgm_check_handler: ...@@ -615,13 +624,15 @@ pgm_check_handler:
tm __LC_PGM_INT_CODE+1,0x80 # check whether we got a per exception tm __LC_PGM_INT_CODE+1,0x80 # check whether we got a per exception
bnz BASED(pgm_per) # got per exception -> special case bnz BASED(pgm_per) # got per exception -> special case
SAVE_ALL __LC_PGM_OLD_PSW,1 SAVE_ALL __LC_PGM_OLD_PSW,1
la %r8,0x7f
l %r3,__LC_PGM_ILC # load program interruption code
l %r7,BASED(.Ljump_table) l %r7,BASED(.Ljump_table)
lh %r8,__LC_PGM_INT_CODE nr %r8,%r3
sll %r8,2 sll %r8,2
GET_THREAD_INFO GET_THREAD_INFO
stosm 24(%r15),0x03 # reenable interrupts
l %r7,0(%r8,%r7) # load address of handler routine l %r7,0(%r8,%r7) # load address of handler routine
la %r2,SP_PTREGS(%r15) # address of register-save area la %r2,SP_PTREGS(%r15) # address of register-save area
l %r3,__LC_PGM_ILC # load program interruption code
la %r14,BASED(sysc_return) la %r14,BASED(sysc_return)
br %r7 # branch to interrupt-handler br %r7 # branch to interrupt-handler
...@@ -646,6 +657,7 @@ pgm_per_std: ...@@ -646,6 +657,7 @@ pgm_per_std:
GET_THREAD_INFO GET_THREAD_INFO
la %r4,0x7f la %r4,0x7f
l %r3,__LC_PGM_ILC # load program interruption code l %r3,__LC_PGM_ILC # load program interruption code
stosm 24(%r15),0x03 # reenable interrupts
nr %r4,%r3 # clear per-event-bit and ilc nr %r4,%r3 # clear per-event-bit and ilc
be BASED(pgm_per_only) # only per or per+check ? be BASED(pgm_per_only) # only per or per+check ?
l %r1,BASED(.Ljump_table) l %r1,BASED(.Ljump_table)
...@@ -665,9 +677,9 @@ pgm_per_only: ...@@ -665,9 +677,9 @@ pgm_per_only:
pgm_svcper: pgm_svcper:
SAVE_ALL __LC_SVC_OLD_PSW,1 SAVE_ALL __LC_SVC_OLD_PSW,1
GET_THREAD_INFO # load pointer to task_struct to R9 GET_THREAD_INFO # load pointer to task_struct to R9
stosm 24(%r15),0x03 # reenable interrupts
lh %r8,0x8a # get svc number from lowcore lh %r8,0x8a # get svc number from lowcore
sll %r8,2 sll %r8,2
stosm 24(%r15),0x03 # reenable interrupts
l %r8,sys_call_table-entry_base(%r8,%r13) # get system call addr. l %r8,sys_call_table-entry_base(%r8,%r13) # get system call addr.
tm __TI_flags+3(%r9),_TIF_SYSCALL_TRACE tm __TI_flags+3(%r9),_TIF_SYSCALL_TRACE
bo BASED(pgm_tracesys) bo BASED(pgm_tracesys)
...@@ -731,59 +743,81 @@ io_int_handler: ...@@ -731,59 +743,81 @@ io_int_handler:
basr %r14,%r1 # branch to standard irq handler basr %r14,%r1 # branch to standard irq handler
io_return: io_return:
# tm SP_PSW+1(%r15),0x01 # returning to user ?
# check, if bottom-half has to be done #ifdef CONFIG_PREEMPT
# bno BASED(io_preempt) # no -> check for preemptive scheduling
l %r1,__TI_cpu(%r9) #else
sll %r1,L1_CACHE_SHIFT bno BASED(io_leave) # no-> skip resched & signal
al %r1,BASED(.Lirq_stat) # get address of irq_stat #endif
icm %r0,15,0(%r1) # test irq_stat[#cpu].__softirq_pending
bnz BASED(io_handle_bottom_half)
io_return_bh:
tm __TI_flags+3(%r9),_TIF_WORK_MASK tm __TI_flags+3(%r9),_TIF_WORK_MASK
bnz BASED(io_work) # there is work to do (signals etc.) bnz BASED(io_work) # there is work to do (signals etc.)
io_leave: io_leave:
stnsm 24(%r15),0xfc # disable I/O and ext. interrupts
RESTORE_ALL 0 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: io_work_loop:
l %r1,BASED(.Ldo_softirq) stnsm 24(%r15),0xfc # disable I/O and ext. interrupts
la %r14,BASED(io_return_bh) GET_THREAD_INFO # load pointer to task_struct to R9
br %r1 # call do_softirq 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 # One of the work bits is on. Find out which one.
# _TIF_NEED_RESCHED is on. Find out which one. # Checked are: _TIF_SIGPENDING and _TIF_NEED_RESCHED
# #
io_work: 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 tm __TI_flags+3(%r9),_TIF_NEED_RESCHED
bo BASED(io_reschedule) bo BASED(io_reschedule)
# add a test for TIF_NOTIFY_RESUME here when it is used. tm __TI_flags+3(%r9),_TIF_SIGPENDING
# _TIF_SIGPENDING is the only flag left bo BASED(io_sigpending)
b BASED(io_leave)
# #
# call do_signal before return # _TIF_NEED_RESCHED is set, call schedule
# #
io_signal_return: io_reschedule:
la %r2,SP_PTREGS(%r15) # load pt_regs stosm 24(%r15),0x03 # reenable interrupts
sr %r3,%r3 # clear *oldset l %r1,BASED(.Lschedule)
l %r1,BASED(.Ldo_signal) la %r14,BASED(io_work_loop)
la %r14,BASED(io_leave) br %r1 # call scheduler
br %r1 # return point is io_leave
# #
# call schedule with io_return as return-address # _TIF_SIGPENDING is set, call do_signal
# #
io_reschedule: io_sigpending:
l %r1,BASED(.Lschedule) stosm 24(%r15),0x03 # reenable interrupts
la %r14,BASED(io_return) la %r2,SP_PTREGS(%r15) # load pt_regs
br %r1 # call scheduler, return to io_return 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 * External interrupt handler routine
...@@ -864,19 +898,12 @@ restart_go: ...@@ -864,19 +898,12 @@ restart_go:
.align 4 .align 4
.Lc0xfffffff8: .long -8 # to align stack pointer to 8 .Lc0xfffffff8: .long -8 # to align stack pointer to 8
.Lc0xffffe000: .long -8192 # to round stack pointer to &task_struct .Lc0xffffe000: .long -8192 # to round stack pointer to &task_struct
.Lc8191: .long 8191
.Lc_spsize: .long SP_SIZE .Lc_spsize: .long SP_SIZE
.Lc_overhead: .long STACK_FRAME_OVERHEAD .Lc_overhead: .long STACK_FRAME_OVERHEAD
.Lc_ac: .long 0,0,1 .Lc_ac: .long 0,0,1
.Lc_ENOSYS: .long -ENOSYS .Lc_ENOSYS: .long -ENOSYS
.Lc4: .long 4 .Lc_pactive: .long PREEMPT_ACTIVE
.Lc20: .long 20
.Lc0x1202: .long 0x1202
.Lc0x1004: .long 0x1004
.Lc0x2401: .long 0x2401
.Lc0x4000: .long 0x4000
.Lc0xff: .long 0xff .Lc0xff: .long 0xff
.Lc128: .long 128
.Lc256: .long 256 .Lc256: .long 256
/* /*
...@@ -889,7 +916,6 @@ restart_go: ...@@ -889,7 +916,6 @@ restart_go:
.Lentry_base: .long entry_base .Lentry_base: .long entry_base
.Lext_hash: .long ext_int_hash .Lext_hash: .long ext_int_hash
.Lhandle_per: .long handle_per_exception .Lhandle_per: .long handle_per_exception
.Lirq_stat: .long irq_stat
.Ljump_table: .long pgm_check_table .Ljump_table: .long pgm_check_table
.Lschedule: .long schedule .Lschedule: .long schedule
.Lclone: .long sys_clone .Lclone: .long sys_clone
...@@ -903,7 +929,7 @@ restart_go: ...@@ -903,7 +929,7 @@ restart_go:
.Lsigaltstack: .long sys_sigaltstack .Lsigaltstack: .long sys_sigaltstack
.Ltrace: .long syscall_trace .Ltrace: .long syscall_trace
.Lvfork: .long sys_vfork .Lvfork: .long sys_vfork
#ifdef CONFIG_SMP #if CONFIG_SMP || CONFIG_PREEMPT
.Lschedtail: .long schedule_tail .Lschedtail: .long schedule_tail
#endif #endif
......
arch/s390x/config.in
View file @ b2a749f0
...@@ -33,6 +33,7 @@ if [ "$CONFIG_QDIO" != "n" ]; then ...@@ -33,6 +33,7 @@ if [ "$CONFIG_QDIO" != "n" ]; then
fi fi
comment 'Misc' comment 'Misc'
bool 'Preemptible Kernel' CONFIG_PREEMPT
bool 'Builtin IPL record support' CONFIG_IPL bool 'Builtin IPL record support' CONFIG_IPL
if [ "$CONFIG_IPL" = "y" ]; then if [ "$CONFIG_IPL" = "y" ]; then
choice 'IPL method generated into head.S' \ choice 'IPL method generated into head.S' \
......
arch/s390x/defconfig
View file @ b2a749f0
...@@ -51,6 +51,7 @@ CONFIG_QDIO=y ...@@ -51,6 +51,7 @@ CONFIG_QDIO=y
# #
# Misc # Misc
# #
# CONFIG_PREEMPT is not set
CONFIG_IPL=y CONFIG_IPL=y
# CONFIG_IPL_TAPE is not set # CONFIG_IPL_TAPE is not set
CONFIG_IPL_VM=y CONFIG_IPL_VM=y
......
arch/s390x/kernel/entry.S
View file @ b2a749f0
...@@ -48,7 +48,7 @@ SP_ORIG_R2 = STACK_FRAME_OVERHEAD + PT_ORIGGPR2 ...@@ -48,7 +48,7 @@ SP_ORIG_R2 = STACK_FRAME_OVERHEAD + PT_ORIGGPR2
SP_TRAP = (SP_ORIG_R2+GPR_SIZE) SP_TRAP = (SP_ORIG_R2+GPR_SIZE)
SP_SIZE = (SP_TRAP+4) 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: * Register usage in interrupt handlers:
...@@ -184,32 +184,42 @@ sysc_leave: ...@@ -184,32 +184,42 @@ sysc_leave:
RESTORE_ALL 1 RESTORE_ALL 1
# #
# One of the work bits _TIF_NOTIFY_RESUME, _TIF_SIGPENDING or # recheck if there is more work to do
# _TIF_NEED_RESCHED is on. Find out which one. #
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: 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 tm __TI_flags+7(%r9),_TIF_NEED_RESCHED
jo sysc_reschedule jo sysc_reschedule
# add a test for TIF_NOTIFY_RESUME here when it is used. tm __TI_flags+7(%r9),_TIF_SIGPENDING
# _TIF_SIGPENDING is the only flag left jo sysc_sigpending
j sysc_leave
# #
# call do_signal before return # _TIF_NEED_RESCHED is set, call schedule
# #
sysc_signal_return: sysc_reschedule:
la %r2,SP_PTREGS(%r15) # load pt_regs stosm 48(%r15),0x03 # reenable interrupts
sgr %r3,%r3 # clear *oldset larl %r14,sysc_work_loop
larl %r14,sysc_return jg schedule # return point is sysc_return
jg do_signal # return point is sysc_return
# #
# call schedule with sysc_return as return-address # _TIF_SIGPENDING is set, call do_signal
# #
sysc_reschedule: sysc_sigpending:
larl %r14,sysc_return stosm 48(%r15),0x03 # reenable interrupts
jg schedule # return point is sysc_return 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 # call syscall_trace before and after system call
...@@ -241,8 +251,7 @@ sysc_tracego: ...@@ -241,8 +251,7 @@ sysc_tracego:
.globl ret_from_fork .globl ret_from_fork
ret_from_fork: ret_from_fork:
GET_THREAD_INFO # load pointer to task_struct to R9 GET_THREAD_INFO # load pointer to task_struct to R9
xc SP_R2(8,%r15),SP_R2(%r15) # child returns 0 #if CONFIG_SMP || CONFIG_PREEMPT
#ifdef CONFIG_SMP
larl %r14,sysc_return larl %r14,sysc_return
jg schedule_tail # return to sysc_return jg schedule_tail # return to sysc_return
#else #else
...@@ -550,8 +559,8 @@ sys_call_table: ...@@ -550,8 +559,8 @@ sys_call_table:
.long SYSCALL(sys_rt_sigtimedwait,sys32_rt_sigtimedwait_wrapper) .long SYSCALL(sys_rt_sigtimedwait,sys32_rt_sigtimedwait_wrapper)
.long SYSCALL(sys_rt_sigqueueinfo,sys32_rt_sigqueueinfo_wrapper) .long SYSCALL(sys_rt_sigqueueinfo,sys32_rt_sigqueueinfo_wrapper)
.long SYSCALL(sys_rt_sigsuspend_glue,sys32_rt_sigsuspend_glue) .long SYSCALL(sys_rt_sigsuspend_glue,sys32_rt_sigsuspend_glue)
.long SYSCALL(sys_pread64,sys32_pread_wrapper) /* 180 */ .long SYSCALL(sys_pread64,sys32_pread64_wrapper) /* 180 */
.long SYSCALL(sys_pwrite64,sys32_pwrite_wrapper) .long SYSCALL(sys_pwrite64,sys32_pwrite64_wrapper)
.long SYSCALL(sys_ni_syscall,sys32_chown16_wrapper) /* old chown16 syscall */ .long SYSCALL(sys_ni_syscall,sys32_chown16_wrapper) /* old chown16 syscall */
.long SYSCALL(sys_getcwd,sys32_getcwd_wrapper) .long SYSCALL(sys_getcwd,sys32_getcwd_wrapper)
.long SYSCALL(sys_capget,sys32_capget_wrapper) .long SYSCALL(sys_capget,sys32_capget_wrapper)
...@@ -645,13 +654,15 @@ pgm_check_handler: ...@@ -645,13 +654,15 @@ pgm_check_handler:
tm __LC_PGM_INT_CODE+1,0x80 # check whether we got a per exception tm __LC_PGM_INT_CODE+1,0x80 # check whether we got a per exception
jnz pgm_per # got per exception -> special case jnz pgm_per # got per exception -> special case
SAVE_ALL __LC_PGM_OLD_PSW,1 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 sll %r8,3
GET_THREAD_INFO GET_THREAD_INFO
stosm 48(%r15),0x03 # reenable interrupts
larl %r1,pgm_check_table larl %r1,pgm_check_table
lg %r1,0(%r8,%r1) # load address of handler routine lg %r1,0(%r8,%r1) # load address of handler routine
la %r2,SP_PTREGS(%r15) # address of register-save area la %r2,SP_PTREGS(%r15) # address of register-save area
lgf %r3,__LC_PGM_ILC # load program interruption code
larl %r14,sysc_return larl %r14,sysc_return
br %r1 # branch to interrupt-handler br %r1 # branch to interrupt-handler
...@@ -675,6 +686,7 @@ pgm_per_std: ...@@ -675,6 +686,7 @@ pgm_per_std:
GET_THREAD_INFO GET_THREAD_INFO
lghi %r4,0x7f lghi %r4,0x7f
lgf %r3,__LC_PGM_ILC # load program interruption code lgf %r3,__LC_PGM_ILC # load program interruption code
stosm 48(%r15),0x03 # reenable interrupts
nr %r4,%r3 # clear per-event-bit and ilc nr %r4,%r3 # clear per-event-bit and ilc
je pgm_per_only # only per of per+check ? je pgm_per_only # only per of per+check ?
sll %r4,3 sll %r4,3
...@@ -758,57 +770,79 @@ io_int_handler: ...@@ -758,57 +770,79 @@ io_int_handler:
brasl %r14,do_IRQ # call standard irq handler brasl %r14,do_IRQ # call standard irq handler
io_return: io_return:
# tm SP_PSW+1(%r15),0x01 # returning to user ?
# check, if bottom-half has to be done #ifdef CONFIG_PREEMPT
# jno io_preempt # no -> check for preemptive scheduling
lgf %r1,__TI_cpu(%r9) #else
larl %r2,irq_stat jno io_leave # no-> skip resched & signal
sll %r1,L1_CACHE_SHIFT #endif
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 __TI_flags+7(%r9),_TIF_WORK_MASK tm __TI_flags+7(%r9),_TIF_WORK_MASK
jnz io_work # there is work to do (signals etc.) jnz io_work # there is work to do (signals etc.)
io_leave: io_leave:
stnsm 48(%r15),0xfc # disable I/O and ext. interrupts
RESTORE_ALL 0 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: io_work_loop:
larl %r14,io_return_bh stnsm 48(%r15),0xfc # disable I/O and ext. interrupts
jg do_softirq # return point is io_return_bh 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 # One of the work bits is on. Find out which one.
# _TIF_NEED_RESCHED is on. Find out which one. # Checked are: _TIF_SIGPENDING and _TIF_NEED_RESCHED
# #
io_work: 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 tm __TI_flags+7(%r9),_TIF_NEED_RESCHED
jo io_reschedule jo io_reschedule
# add a test for TIF_NOTIFY_RESUME here when it is used. tm __TI_flags+7(%r9),_TIF_SIGPENDING
# _TIF_SIGPENDING is the only flag left jo io_sigpending
j io_leave
# #
# call do_signal before return # _TIF_NEED_RESCHED is set, call schedule
# #
io_signal_return: io_reschedule:
la %r2,SP_PTREGS(%r15) # load pt_regs stosm 48(%r15),0x03 # reenable interrupts
slgr %r3,%r3 # clear *oldset larl %r14,io_work_loop
larl %r14,io_leave jg schedule # call scheduler
jg do_signal # return point is io_leave
# #
# call schedule with io_return as return-address # _TIF_SIGPENDING is set, call do_signal
# #
io_reschedule: io_sigpending:
larl %r14,io_return stosm 48(%r15),0x03 # reenable interrupts
jg schedule # call scheduler, return to io_return 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 * External interrupt handler routine
...@@ -882,4 +916,5 @@ restart_go: ...@@ -882,4 +916,5 @@ restart_go:
*/ */
.align 4 .align 4
.Lc_ac: .long 0,0,1 .Lc_ac: .long 0,0,1
.Lc_pactive: .long PREEMPT_ACTIVE
.Lc256: .quad 256 .Lc256: .quad 256
include/asm-s390/hardirq.h
View file @ b2a749f0
...@@ -80,15 +80,21 @@ typedef struct { ...@@ -80,15 +80,21 @@ typedef struct {
extern void do_call_softirq(void); extern void do_call_softirq(void);
#define in_atomic() (preempt_count() != 0) #if CONFIG_PREEMPT
#define IRQ_EXIT_OFFSET HARDIRQ_OFFSET # 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() \ #define irq_exit() \
do { \ do { \
preempt_count() -= HARDIRQ_OFFSET; \ preempt_count() -= IRQ_EXIT_OFFSET; \
if (!in_interrupt() && softirq_pending(smp_processor_id())) \ if (!in_interrupt() && softirq_pending(smp_processor_id())) \
/* Use the async. stack for softirq */ \ /* Use the async. stack for softirq */ \
do_call_softirq(); \ do_call_softirq(); \
preempt_enable_no_resched(); \
} while (0) } while (0)
#ifndef CONFIG_SMP #ifndef CONFIG_SMP
......
include/asm-s390/softirq.h
View file @ b2a749f0
...@@ -10,6 +10,7 @@ ...@@ -10,6 +10,7 @@
#define __ASM_SOFTIRQ_H #define __ASM_SOFTIRQ_H
#include <linux/smp.h> #include <linux/smp.h>
#include <linux/preempt.h>
#include <asm/atomic.h> #include <asm/atomic.h>
#include <asm/hardirq.h> #include <asm/hardirq.h>
...@@ -28,6 +29,7 @@ do { \ ...@@ -28,6 +29,7 @@ do { \
if (!in_interrupt() && softirq_pending(smp_processor_id())) \ if (!in_interrupt() && softirq_pending(smp_processor_id())) \
/* Use the async. stack for softirq */ \ /* Use the async. stack for softirq */ \
do_call_softirq(); \ do_call_softirq(); \
preempt_check_resched(); \
} while (0) } while (0)
#endif /* __ASM_SOFTIRQ_H */ #endif /* __ASM_SOFTIRQ_H */
......
include/asm-s390/thread_info.h
View file @ b2a749f0
...@@ -25,11 +25,9 @@ struct thread_info { ...@@ -25,11 +25,9 @@ struct thread_info {
struct exec_domain *exec_domain; /* execution domain */ struct exec_domain *exec_domain; /* execution domain */
unsigned long flags; /* low level flags */ unsigned long flags; /* low level flags */
unsigned int cpu; /* current CPU */ 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 * macros/functions for gaining access to the thread information structure
*/ */
...@@ -84,4 +82,6 @@ static inline struct thread_info *current_thread_info(void) ...@@ -84,4 +82,6 @@ static inline struct thread_info *current_thread_info(void)
#endif /* __KERNEL__ */ #endif /* __KERNEL__ */
#define PREEMPT_ACTIVE 0x4000000
#endif /* _ASM_THREAD_INFO_H */ #endif /* _ASM_THREAD_INFO_H */
include/asm-s390x/hardirq.h
View file @ b2a749f0
...@@ -81,15 +81,21 @@ typedef struct { ...@@ -81,15 +81,21 @@ typedef struct {
extern void do_call_softirq(void); extern void do_call_softirq(void);
#define in_atomic() (preempt_count() != 0) #if CONFIG_PREEMPT
#define IRQ_EXIT_OFFSET HARDIRQ_OFFSET # 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() \ #define irq_exit() \
do { \ do { \
preempt_count() -= HARDIRQ_OFFSET; \ preempt_count() -= IRQ_EXIT_OFFSET; \
if (!in_interrupt() && softirq_pending(smp_processor_id())) \ if (!in_interrupt() && softirq_pending(smp_processor_id())) \
/* Use the async. stack for softirq */ \ /* Use the async. stack for softirq */ \
do_call_softirq(); \ do_call_softirq(); \
preempt_enable_no_resched(); \
} while (0) } while (0)
#ifndef CONFIG_SMP #ifndef CONFIG_SMP
......
include/asm-s390x/thread_info.h
View file @ b2a749f0
...@@ -25,11 +25,9 @@ struct thread_info { ...@@ -25,11 +25,9 @@ struct thread_info {
struct exec_domain *exec_domain; /* execution domain */ struct exec_domain *exec_domain; /* execution domain */
unsigned long flags; /* low level flags */ unsigned long flags; /* low level flags */
unsigned int cpu; /* current CPU */ 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 * macros/functions for gaining access to the thread information structure
*/ */
...@@ -84,4 +82,6 @@ static inline struct thread_info *current_thread_info(void) ...@@ -84,4 +82,6 @@ static inline struct thread_info *current_thread_info(void)
#endif /* __KERNEL__ */ #endif /* __KERNEL__ */
#define PREEMPT_ACTIVE 0x4000000
#endif /* _ASM_THREAD_INFO_H */ #endif /* _ASM_THREAD_INFO_H */
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