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authorMartin Schwidefsky <schwidefsky@de.ibm.com>2010-05-17 10:00:02 +0200
committerMartin Schwidefsky <sky@mschwide.boeblingen.de.ibm.com>2010-05-17 10:00:15 +0200
commit6a2df3a87276cdc08fd87070d09ea18d1fb9d622 (patch)
tree384b646d0a826ab5c2bafa63e9bea4a057815fe2 /arch/s390/kernel/entry64.S
parent43d399d2ab7e96cb8d952d0ba4e9131587b7c8b9 (diff)
downloadop-kernel-dev-6a2df3a87276cdc08fd87070d09ea18d1fb9d622.zip
op-kernel-dev-6a2df3a87276cdc08fd87070d09ea18d1fb9d622.tar.gz
[S390] improve irq tracing code in entry[64].S
The system call path in entry[64].S is run with interrupts enabled. Remove the irq tracing check from the system call exit code. If a program check interrupted a context enabled for interrupts do a call to trace_irq_off_caller in the program check handler before branching to the system call exit code. Restructure the system call and io interrupt return code to avoid avoid the lpsw[e] to disable machine checks. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Diffstat (limited to 'arch/s390/kernel/entry64.S')
-rw-r--r--arch/s390/kernel/entry64.S197
1 files changed, 92 insertions, 105 deletions
diff --git a/arch/s390/kernel/entry64.S b/arch/s390/kernel/entry64.S
index ca02b10..860cea1 100644
--- a/arch/s390/kernel/entry64.S
+++ b/arch/s390/kernel/entry64.S
@@ -61,28 +61,33 @@ _TIF_SYSCALL = (_TIF_SYSCALL_TRACE>>8 | _TIF_SYSCALL_AUDIT>>8 | \
#ifdef CONFIG_TRACE_IRQFLAGS
.macro TRACE_IRQS_ON
- basr %r2,%r0
- brasl %r14,trace_hardirqs_on_caller
+ basr %r2,%r0
+ brasl %r14,trace_hardirqs_on_caller
.endm
.macro TRACE_IRQS_OFF
- basr %r2,%r0
- brasl %r14,trace_hardirqs_off_caller
+ basr %r2,%r0
+ brasl %r14,trace_hardirqs_off_caller
.endm
- .macro TRACE_IRQS_CHECK
- basr %r2,%r0
+ .macro TRACE_IRQS_CHECK_ON
tm SP_PSW(%r15),0x03 # irqs enabled?
jz 0f
- brasl %r14,trace_hardirqs_on_caller
- j 1f
-0: brasl %r14,trace_hardirqs_off_caller
-1:
+ TRACE_IRQS_ON
+0:
+ .endm
+
+ .macro TRACE_IRQS_CHECK_OFF
+ tm SP_PSW(%r15),0x03 # irqs enabled?
+ jz 0f
+ TRACE_IRQS_OFF
+0:
.endm
#else
#define TRACE_IRQS_ON
#define TRACE_IRQS_OFF
-#define TRACE_IRQS_CHECK
+#define TRACE_IRQS_CHECK_ON
+#define TRACE_IRQS_CHECK_OFF
#endif
#ifdef CONFIG_LOCKDEP
@@ -267,29 +272,14 @@ sysc_noemu:
stg %r2,SP_R2(%r15) # store return value (change R2 on stack)
sysc_return:
+ LOCKDEP_SYS_EXIT
+sysc_tif:
tm __TI_flags+7(%r9),_TIF_WORK_SVC
jnz sysc_work # there is work to do (signals etc.)
sysc_restore:
-#ifdef CONFIG_TRACE_IRQFLAGS
- larl %r1,sysc_restore_trace_psw
- lpswe 0(%r1)
-sysc_restore_trace:
- TRACE_IRQS_CHECK
- LOCKDEP_SYS_EXIT
-#endif
-sysc_leave:
RESTORE_ALL __LC_RETURN_PSW,1
sysc_done:
-#ifdef CONFIG_TRACE_IRQFLAGS
- .section .data,"aw",@progbits
- .align 8
- .globl sysc_restore_trace_psw
-sysc_restore_trace_psw:
- .quad 0, sysc_restore_trace
- .previous
-#endif
-
#
# There is work to do, but first we need to check if we return to userspace.
#
@@ -300,7 +290,7 @@ sysc_work:
#
# One of the work bits is on. Find out which one.
#
-sysc_work_loop:
+sysc_work_tif:
tm __TI_flags+7(%r9),_TIF_MCCK_PENDING
jo sysc_mcck_pending
tm __TI_flags+7(%r9),_TIF_NEED_RESCHED
@@ -319,14 +309,14 @@ sysc_work_loop:
# _TIF_NEED_RESCHED is set, call schedule
#
sysc_reschedule:
- larl %r14,sysc_work_loop
- jg schedule # return point is sysc_work_loop
+ larl %r14,sysc_return
+ jg schedule # return point is sysc_return
#
# _TIF_MCCK_PENDING is set, call handler
#
sysc_mcck_pending:
- larl %r14,sysc_work_loop
+ larl %r14,sysc_return
jg s390_handle_mcck # TIF bit will be cleared by handler
#
@@ -340,14 +330,14 @@ sysc_sigpending:
jo sysc_restart
tm __TI_flags+7(%r9),_TIF_SINGLE_STEP
jo sysc_singlestep
- j sysc_work_loop
+ j sysc_return
#
# _TIF_NOTIFY_RESUME is set, call do_notify_resume
#
sysc_notify_resume:
la %r2,SP_PTREGS(%r15) # load pt_regs
- larl %r14,sysc_work_loop
+ larl %r14,sysc_return
jg do_notify_resume # call do_notify_resume
#
@@ -367,7 +357,7 @@ sysc_singlestep:
ni __TI_flags+7(%r9),255-_TIF_SINGLE_STEP # clear TIF_SINGLE_STEP
xc SP_SVCNR(2,%r15),SP_SVCNR(%r15) # clear svc number
la %r2,SP_PTREGS(%r15) # address of register-save area
- larl %r14,sysc_work_loop # load adr. of system return
+ larl %r14,sysc_return # load adr. of system return
jg do_single_step # branch to do_sigtrap
#
@@ -433,12 +423,14 @@ kernel_execve:
br %r14
# execve succeeded.
0: stnsm __SF_EMPTY(%r15),0xfc # disable interrupts
+# TRACE_IRQS_OFF
lg %r15,__LC_KERNEL_STACK # load ksp
aghi %r15,-SP_SIZE # make room for registers & psw
lg %r13,__LC_SVC_NEW_PSW+8
lg %r9,__LC_THREAD_INFO
mvc SP_PTREGS(__PT_SIZE,%r15),0(%r12) # copy pt_regs
xc __SF_BACKCHAIN(8,%r15),__SF_BACKCHAIN(%r15)
+# TRACE_IRQS_ON
stosm __SF_EMPTY(%r15),0x03 # reenable interrupts
brasl %r14,execve_tail
j sysc_return
@@ -474,9 +466,9 @@ pgm_check_handler:
UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
mvc __LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
pgm_no_vtime:
+ TRACE_IRQS_CHECK_OFF
lg %r9,__LC_THREAD_INFO # load pointer to thread_info struct
mvc SP_ARGS(8,%r15),__LC_LAST_BREAK
- TRACE_IRQS_OFF
lgf %r3,__LC_PGM_ILC # load program interruption code
lghi %r8,0x7f
ngr %r8,%r3
@@ -485,8 +477,10 @@ pgm_do_call:
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
- larl %r14,sysc_return
- br %r1 # branch to interrupt-handler
+ basr %r14,%r1 # branch to interrupt-handler
+pgm_exit:
+ TRACE_IRQS_CHECK_ON
+ j sysc_return
#
# handle per exception
@@ -513,8 +507,8 @@ pgm_per_std:
UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER
mvc __LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
pgm_no_vtime2:
+ TRACE_IRQS_CHECK_OFF
lg %r9,__LC_THREAD_INFO # load pointer to thread_info struct
- TRACE_IRQS_OFF
lg %r1,__TI_task(%r9)
tm SP_PSW+1(%r15),0x01 # kernel per event ?
jz kernel_per
@@ -525,7 +519,7 @@ pgm_no_vtime2:
lgf %r3,__LC_PGM_ILC # load program interruption code
lghi %r8,0x7f
ngr %r8,%r3 # clear per-event-bit and ilc
- je sysc_return
+ je pgm_exit
j pgm_do_call
#
@@ -539,14 +533,15 @@ pgm_svcper:
mvc __LC_LAST_UPDATE_TIMER(8),__LC_SYNC_ENTER_TIMER
llgh %r7,__LC_SVC_INT_CODE # get svc number from lowcore
lg %r9,__LC_THREAD_INFO # load pointer to thread_info struct
+ TRACE_IRQS_OFF
lg %r8,__TI_task(%r9)
mvc __THREAD_per+__PER_atmid(2,%r8),__LC_PER_ATMID
mvc __THREAD_per+__PER_address(8,%r8),__LC_PER_ADDRESS
mvc __THREAD_per+__PER_access_id(1,%r8),__LC_PER_ACCESS_ID
oi __TI_flags+7(%r9),_TIF_SINGLE_STEP # set TIF_SINGLE_STEP
TRACE_IRQS_ON
- lmg %r2,%r6,SP_R2(%r15) # load svc arguments
stosm __SF_EMPTY(%r15),0x03 # reenable interrupts
+ lmg %r2,%r6,SP_R2(%r15) # load svc arguments
j sysc_do_svc
#
@@ -555,8 +550,8 @@ pgm_svcper:
kernel_per:
xc SP_SVCNR(2,%r15),SP_SVCNR(%r15) # clear svc number
la %r2,SP_PTREGS(%r15) # address of register-save area
- larl %r14,sysc_restore # load adr. of system ret, no work
- jg do_single_step # branch to do_single_step
+ brasl %r14,do_single_step
+ j pgm_exit
/*
* IO interrupt handler routine
@@ -579,29 +574,15 @@ io_no_vtime:
la %r2,SP_PTREGS(%r15) # address of register-save area
brasl %r14,do_IRQ # call standard irq handler
io_return:
+ LOCKDEP_SYS_EXIT
+ TRACE_IRQS_ON
+io_tif:
tm __TI_flags+7(%r9),_TIF_WORK_INT
jnz io_work # there is work to do (signals etc.)
io_restore:
-#ifdef CONFIG_TRACE_IRQFLAGS
- larl %r1,io_restore_trace_psw
- lpswe 0(%r1)
-io_restore_trace:
- TRACE_IRQS_CHECK
- LOCKDEP_SYS_EXIT
-#endif
-io_leave:
RESTORE_ALL __LC_RETURN_PSW,0
io_done:
-#ifdef CONFIG_TRACE_IRQFLAGS
- .section .data,"aw",@progbits
- .align 8
- .globl io_restore_trace_psw
-io_restore_trace_psw:
- .quad 0, io_restore_trace
- .previous
-#endif
-
#
# There is work todo, find out in which context we have been interrupted:
# 1) if we return to user space we can do all _TIF_WORK_INT work
@@ -627,18 +608,22 @@ io_work:
# check for preemptive scheduling
icm %r0,15,__TI_precount(%r9)
jnz io_restore # preemption is disabled
+ tm __TI_flags+7(%r12),_TIF_NEED_RESCHED
+ jno io_restore
# switch to kernel stack
lg %r1,SP_R15(%r15)
aghi %r1,-SP_SIZE
mvc SP_PTREGS(__PT_SIZE,%r1),SP_PTREGS(%r15)
xc __SF_BACKCHAIN(8,%r1),__SF_BACKCHAIN(%r1) # clear back chain
lgr %r15,%r1
-io_resume_loop:
- larl %r14,io_resume_loop
- tm __TI_flags+7(%r12),_TIF_NEED_RESCHED
- jgo preempt_schedule_irq
-#endif
+ # TRACE_IRQS_ON already done at io_return, call
+ # TRACE_IRQS_OFF to keep things symmetrical
+ TRACE_IRQS_OFF
+ brasl %r14,preempt_schedule_irq
+ j io_return
+#else
j io_restore
+#endif
#
# Need to do work before returning to userspace, switch to kernel stack
@@ -655,7 +640,7 @@ io_work_user:
# Checked are: _TIF_SIGPENDING, _TIF_NOTIFY_RESUME, _TIF_NEED_RESCHED
# and _TIF_MCCK_PENDING
#
-io_work_loop:
+io_work_tif:
tm __TI_flags+7(%r9),_TIF_MCCK_PENDING
jo io_mcck_pending
tm __TI_flags+7(%r9),_TIF_NEED_RESCHED
@@ -670,43 +655,45 @@ io_work_loop:
# _TIF_MCCK_PENDING is set, call handler
#
io_mcck_pending:
+ # TRACE_IRQS_ON already done at io_return
brasl %r14,s390_handle_mcck # TIF bit will be cleared by handler
- j io_work_loop
+ TRACE_IRQS_OFF
+ j io_return
#
# _TIF_NEED_RESCHED is set, call schedule
#
io_reschedule:
- TRACE_IRQS_ON
+ # TRACE_IRQS_ON already done at io_return
stosm __SF_EMPTY(%r15),0x03 # reenable interrupts
brasl %r14,schedule # call scheduler
stnsm __SF_EMPTY(%r15),0xfc # disable I/O and ext. interrupts
TRACE_IRQS_OFF
- j io_work_loop
+ j io_return
#
# _TIF_SIGPENDING or is set, call do_signal
#
io_sigpending:
- TRACE_IRQS_ON
+ # TRACE_IRQS_ON already done at io_return
stosm __SF_EMPTY(%r15),0x03 # reenable interrupts
la %r2,SP_PTREGS(%r15) # load pt_regs
brasl %r14,do_signal # call do_signal
stnsm __SF_EMPTY(%r15),0xfc # disable I/O and ext. interrupts
TRACE_IRQS_OFF
- j io_work_loop
+ j io_return
#
# _TIF_NOTIFY_RESUME or is set, call do_notify_resume
#
io_notify_resume:
- TRACE_IRQS_ON
+ # TRACE_IRQS_ON already done at io_return
stosm __SF_EMPTY(%r15),0x03 # reenable interrupts
la %r2,SP_PTREGS(%r15) # load pt_regs
brasl %r14,do_notify_resume # call do_notify_resume
stnsm __SF_EMPTY(%r15),0xfc # disable I/O and ext. interrupts
TRACE_IRQS_OFF
- j io_work_loop
+ j io_return
/*
* External interrupt handler routine
@@ -883,14 +870,14 @@ stack_overflow:
cleanup_table_system_call:
.quad system_call, sysc_do_svc
-cleanup_table_sysc_return:
- .quad sysc_return, sysc_leave
-cleanup_table_sysc_leave:
- .quad sysc_leave, sysc_done
-cleanup_table_io_return:
- .quad io_return, io_leave
-cleanup_table_io_leave:
- .quad io_leave, io_done
+cleanup_table_sysc_tif:
+ .quad sysc_tif, sysc_restore
+cleanup_table_sysc_restore:
+ .quad sysc_restore, sysc_done
+cleanup_table_io_tif:
+ .quad io_tif, io_restore
+cleanup_table_io_restore:
+ .quad io_restore, io_done
cleanup_critical:
clc 8(8,%r12),BASED(cleanup_table_system_call)
@@ -898,25 +885,25 @@ cleanup_critical:
clc 8(8,%r12),BASED(cleanup_table_system_call+8)
jl cleanup_system_call
0:
- clc 8(8,%r12),BASED(cleanup_table_sysc_return)
+ clc 8(8,%r12),BASED(cleanup_table_sysc_tif)
jl 0f
- clc 8(8,%r12),BASED(cleanup_table_sysc_return+8)
- jl cleanup_sysc_return
+ clc 8(8,%r12),BASED(cleanup_table_sysc_tif+8)
+ jl cleanup_sysc_tif
0:
- clc 8(8,%r12),BASED(cleanup_table_sysc_leave)
+ clc 8(8,%r12),BASED(cleanup_table_sysc_restore)
jl 0f
- clc 8(8,%r12),BASED(cleanup_table_sysc_leave+8)
- jl cleanup_sysc_leave
+ clc 8(8,%r12),BASED(cleanup_table_sysc_restore+8)
+ jl cleanup_sysc_restore
0:
- clc 8(8,%r12),BASED(cleanup_table_io_return)
+ clc 8(8,%r12),BASED(cleanup_table_io_tif)
jl 0f
- clc 8(8,%r12),BASED(cleanup_table_io_return+8)
- jl cleanup_io_return
+ clc 8(8,%r12),BASED(cleanup_table_io_tif+8)
+ jl cleanup_io_tif
0:
- clc 8(8,%r12),BASED(cleanup_table_io_leave)
+ clc 8(8,%r12),BASED(cleanup_table_io_restore)
jl 0f
- clc 8(8,%r12),BASED(cleanup_table_io_leave+8)
- jl cleanup_io_leave
+ clc 8(8,%r12),BASED(cleanup_table_io_restore+8)
+ jl cleanup_io_restore
0:
br %r14
@@ -963,16 +950,16 @@ cleanup_system_call_insn:
.quad sysc_stime
.quad sysc_update
-cleanup_sysc_return:
+cleanup_sysc_tif:
mvc __LC_RETURN_PSW(8),0(%r12)
- mvc __LC_RETURN_PSW+8(8),BASED(cleanup_table_sysc_return)
+ mvc __LC_RETURN_PSW+8(8),BASED(cleanup_table_sysc_tif)
la %r12,__LC_RETURN_PSW
br %r14
-cleanup_sysc_leave:
- clc 8(8,%r12),BASED(cleanup_sysc_leave_insn)
+cleanup_sysc_restore:
+ clc 8(8,%r12),BASED(cleanup_sysc_restore_insn)
je 3f
- clc 8(8,%r12),BASED(cleanup_sysc_leave_insn+8)
+ clc 8(8,%r12),BASED(cleanup_sysc_restore_insn+8)
jhe 0f
mvc __LC_EXIT_TIMER(8),__LC_ASYNC_ENTER_TIMER
0: mvc __LC_RETURN_PSW(16),SP_PSW(%r15)
@@ -985,20 +972,20 @@ cleanup_sysc_leave:
lg %r15,SP_R15(%r15)
3: la %r12,__LC_RETURN_PSW
br %r14
-cleanup_sysc_leave_insn:
+cleanup_sysc_restore_insn:
.quad sysc_done - 4
.quad sysc_done - 16
-cleanup_io_return:
+cleanup_io_tif:
mvc __LC_RETURN_PSW(8),0(%r12)
- mvc __LC_RETURN_PSW+8(8),BASED(cleanup_table_io_return)
+ mvc __LC_RETURN_PSW+8(8),BASED(cleanup_table_io_tif)
la %r12,__LC_RETURN_PSW
br %r14
-cleanup_io_leave:
- clc 8(8,%r12),BASED(cleanup_io_leave_insn)
+cleanup_io_restore:
+ clc 8(8,%r12),BASED(cleanup_io_restore_insn)
je 3f
- clc 8(8,%r12),BASED(cleanup_io_leave_insn+8)
+ clc 8(8,%r12),BASED(cleanup_io_restore_insn+8)
jhe 0f
mvc __LC_EXIT_TIMER(8),__LC_ASYNC_ENTER_TIMER
0: mvc __LC_RETURN_PSW(16),SP_PSW(%r15)
@@ -1011,7 +998,7 @@ cleanup_io_leave:
lg %r15,SP_R15(%r15)
3: la %r12,__LC_RETURN_PSW
br %r14
-cleanup_io_leave_insn:
+cleanup_io_restore_insn:
.quad io_done - 4
.quad io_done - 16
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