From 6a2df3a87276cdc08fd87070d09ea18d1fb9d622 Mon Sep 17 00:00:00 2001 From: Martin Schwidefsky <schwidefsky@de.ibm.com> Date: Mon, 17 May 2010 10:00:02 +0200 Subject: [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> --- arch/s390/kernel/entry64.S | 197 +++++++++++++++++++++------------------------ 1 file changed, 92 insertions(+), 105 deletions(-) (limited to 'arch/s390/kernel/entry64.S') diff --git a/arch/s390/kernel/entry64.S b/arch/s390/kernel/entry64.S index ca02b10a2c32..860cea1d1c8a 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 -- cgit v1.2.3