From 6a2df3a87276cdc08fd87070d09ea18d1fb9d622 Mon Sep 17 00:00:00 2001 From: Martin Schwidefsky 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 --- arch/s390/kernel/entry.S | 205 +++++++++++++++++++++-------------------------- 1 file changed, 91 insertions(+), 114 deletions(-) (limited to 'arch/s390/kernel/entry.S') diff --git a/arch/s390/kernel/entry.S b/arch/s390/kernel/entry.S index ffebfb64b913..07d849995dac 100644 --- a/arch/s390/kernel/entry.S +++ b/arch/s390/kernel/entry.S @@ -73,21 +73,24 @@ STACK_SIZE = 1 << STACK_SHIFT basr %r14,%r1 .endm - .macro TRACE_IRQS_CHECK - basr %r2,%r0 + .macro TRACE_IRQS_CHECK_ON tm SP_PSW(%r15),0x03 # irqs enabled? - jz 0f - l %r1,BASED(.Ltrace_irq_on_caller) - basr %r14,%r1 - j 1f -0: l %r1,BASED(.Ltrace_irq_off_caller) - basr %r14,%r1 -1: + bz BASED(0f) + TRACE_IRQS_ON +0: + .endm + + .macro TRACE_IRQS_CHECK_OFF + tm SP_PSW(%r15),0x03 # irqs enabled? + bz BASED(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 @@ -273,33 +276,14 @@ sysc_do_restart: st %r2,SP_R2(%r15) # store return value (change R2 on stack) sysc_return: + LOCKDEP_SYS_EXIT +sysc_tif: tm __TI_flags+3(%r9),_TIF_WORK_SVC bnz BASED(sysc_work) # there is work to do (signals etc.) sysc_restore: -#ifdef CONFIG_TRACE_IRQFLAGS - la %r1,BASED(sysc_restore_trace_psw_addr) - l %r1,0(%r1) - lpsw 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 -sysc_restore_trace_psw_addr: - .long sysc_restore_trace_psw - - .section .data,"aw",@progbits - .align 8 - .globl sysc_restore_trace_psw -sysc_restore_trace_psw: - .long 0, sysc_restore_trace + 0x80000000 - .previous -#endif - # # There is work to do, but first we need to check if we return to userspace. # @@ -310,7 +294,7 @@ sysc_work: # # One of the work bits is on. Find out which one. # -sysc_work_loop: +sysc_work_tif: tm __TI_flags+3(%r9),_TIF_MCCK_PENDING bo BASED(sysc_mcck_pending) tm __TI_flags+3(%r9),_TIF_NEED_RESCHED @@ -330,7 +314,7 @@ sysc_work_loop: # sysc_reschedule: l %r1,BASED(.Lschedule) - la %r14,BASED(sysc_work_loop) + la %r14,BASED(sysc_return) br %r1 # call scheduler # @@ -338,7 +322,7 @@ sysc_reschedule: # sysc_mcck_pending: l %r1,BASED(.Ls390_handle_mcck) - la %r14,BASED(sysc_work_loop) + la %r14,BASED(sysc_return) br %r1 # TIF bit will be cleared by handler # @@ -353,7 +337,7 @@ sysc_sigpending: bo BASED(sysc_restart) tm __TI_flags+3(%r9),_TIF_SINGLE_STEP bo BASED(sysc_singlestep) - b BASED(sysc_work_loop) + b BASED(sysc_return) # # _TIF_NOTIFY_RESUME is set, call do_notify_resume @@ -361,7 +345,7 @@ sysc_sigpending: sysc_notify_resume: la %r2,SP_PTREGS(%r15) # load pt_regs l %r1,BASED(.Ldo_notify_resume) - la %r14,BASED(sysc_work_loop) + la %r14,BASED(sysc_return) br %r1 # call do_notify_resume @@ -384,7 +368,7 @@ sysc_singlestep: mvi SP_SVCNR+1(%r15),0xff la %r2,SP_PTREGS(%r15) # address of register-save area l %r1,BASED(.Lhandle_per) # load adr. of per handler - la %r14,BASED(sysc_work_loop) # load adr. of system return + la %r14,BASED(sysc_return) # load adr. of system return br %r1 # branch to do_single_step # @@ -456,11 +440,13 @@ kernel_execve: br %r14 # execve succeeded. 0: stnsm __SF_EMPTY(%r15),0xfc # disable interrupts + TRACE_IRQS_OFF l %r15,__LC_KERNEL_STACK # load ksp s %r15,BASED(.Lc_spsize) # make room for registers & psw l %r9,__LC_THREAD_INFO mvc SP_PTREGS(__PT_SIZE,%r15),0(%r12) # copy pt_regs xc __SF_BACKCHAIN(4,%r15),__SF_BACKCHAIN(%r15) + TRACE_IRQS_ON stosm __SF_EMPTY(%r15),0x03 # reenable interrupts l %r1,BASED(.Lexecve_tail) basr %r14,%r1 @@ -497,8 +483,8 @@ 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 l %r9,__LC_THREAD_INFO # load pointer to thread_info struct - TRACE_IRQS_OFF l %r3,__LC_PGM_ILC # load program interruption code la %r8,0x7f nr %r8,%r3 @@ -507,8 +493,10 @@ pgm_do_call: sll %r8,2 l %r7,0(%r8,%r7) # load address of handler routine la %r2,SP_PTREGS(%r15) # address of register-save area - la %r14,BASED(sysc_return) - br %r7 # branch to interrupt-handler + basr %r14,%r7 # branch to interrupt-handler +pgm_exit: + TRACE_IRQS_CHECK_ON + b BASED(sysc_return) # # handle per exception @@ -535,19 +523,19 @@ 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 l %r9,__LC_THREAD_INFO # load pointer to thread_info struct - TRACE_IRQS_OFF l %r1,__TI_task(%r9) + tm SP_PSW+1(%r15),0x01 # kernel per event ? + bz BASED(kernel_per) mvc __THREAD_per+__PER_atmid(2,%r1),__LC_PER_ATMID mvc __THREAD_per+__PER_address(4,%r1),__LC_PER_ADDRESS mvc __THREAD_per+__PER_access_id(1,%r1),__LC_PER_ACCESS_ID oi __TI_flags+3(%r9),_TIF_SINGLE_STEP # set TIF_SINGLE_STEP - tm SP_PSW+1(%r15),0x01 # kernel per event ? - bz BASED(kernel_per) l %r3,__LC_PGM_ILC # load program interruption code la %r8,0x7f nr %r8,%r3 # clear per-event-bit and ilc - be BASED(sysc_return) # only per or per+check ? + be BASED(pgm_exit) # only per or per+check ? b BASED(pgm_do_call) # @@ -568,8 +556,8 @@ pgm_svcper: mvc __THREAD_per+__PER_access_id(1,%r8),__LC_PER_ACCESS_ID oi __TI_flags+3(%r9),_TIF_SINGLE_STEP # set TIF_SINGLE_STEP TRACE_IRQS_ON - lm %r2,%r6,SP_R2(%r15) # load svc arguments stosm __SF_EMPTY(%r15),0x03 # reenable interrupts + lm %r2,%r6,SP_R2(%r15) # load svc arguments b BASED(sysc_do_svc) # @@ -580,8 +568,8 @@ kernel_per: mvi SP_SVCNR+1(%r15),0xff la %r2,SP_PTREGS(%r15) # address of register-save area l %r1,BASED(.Lhandle_per) # load adr. of per handler - la %r14,BASED(sysc_restore)# load adr. of system return - br %r1 # branch to do_single_step + basr %r14,%r1 # branch to do_single_step + b BASED(pgm_exit) /* * IO interrupt handler routine @@ -600,39 +588,21 @@ io_int_handler: UPDATE_VTIME __LC_LAST_UPDATE_TIMER,__LC_EXIT_TIMER,__LC_SYSTEM_TIMER mvc __LC_LAST_UPDATE_TIMER(8),__LC_ASYNC_ENTER_TIMER io_no_vtime: - l %r9,__LC_THREAD_INFO # load pointer to thread_info struct TRACE_IRQS_OFF + l %r9,__LC_THREAD_INFO # load pointer to thread_info struct l %r1,BASED(.Ldo_IRQ) # load address of do_IRQ la %r2,SP_PTREGS(%r15) # address of register-save area basr %r14,%r1 # branch to standard irq handler io_return: + LOCKDEP_SYS_EXIT + TRACE_IRQS_ON +io_tif: tm __TI_flags+3(%r9),_TIF_WORK_INT bnz BASED(io_work) # there is work to do (signals etc.) io_restore: -#ifdef CONFIG_TRACE_IRQFLAGS - la %r1,BASED(io_restore_trace_psw_addr) - l %r1,0(%r1) - lpsw 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 -io_restore_trace_psw_addr: - .long io_restore_trace_psw - - .section .data,"aw",@progbits - .align 8 - .globl io_restore_trace_psw -io_restore_trace_psw: - .long 0, io_restore_trace + 0x80000000 - .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 @@ -647,19 +617,23 @@ io_work: # check for preemptive scheduling icm %r0,15,__TI_precount(%r9) bnz BASED(io_restore) # preemption disabled + tm __TI_flags+3(%r9),_TIF_NEED_RESCHED + bno BASED(io_restore) # switch to kernel stack l %r1,SP_R15(%r15) s %r1,BASED(.Lc_spsize) mvc SP_PTREGS(__PT_SIZE,%r1),SP_PTREGS(%r15) xc __SF_BACKCHAIN(4,%r1),__SF_BACKCHAIN(%r1) # clear back chain lr %r15,%r1 -io_resume_loop: + # TRACE_IRQS_ON already done at io_return, call + # TRACE_IRQS_OFF to keep things symmetrical + TRACE_IRQS_OFF l %r1,BASED(.Lpreempt_schedule_irq) - la %r14,BASED(io_resume_loop) - tm __TI_flags+3(%r9),_TIF_NEED_RESCHED - bor %r1 # call preempt_schedule_irq -#endif + basr %r14,%r1 # call preempt_schedule_irq + b BASED(io_return) +#else b BASED(io_restore) +#endif # # Need to do work before returning to userspace, switch to kernel stack @@ -670,12 +644,13 @@ io_work_user: mvc SP_PTREGS(__PT_SIZE,%r1),SP_PTREGS(%r15) xc __SF_BACKCHAIN(4,%r1),__SF_BACKCHAIN(%r1) # clear back chain lr %r15,%r1 + # # One of the work bits is on. Find out which one. # Checked are: _TIF_SIGPENDING, _TIF_NOTIFY_RESUME, _TIF_NEED_RESCHED # and _TIF_MCCK_PENDING # -io_work_loop: +io_work_tif: tm __TI_flags+3(%r9),_TIF_MCCK_PENDING bo BASED(io_mcck_pending) tm __TI_flags+3(%r9),_TIF_NEED_RESCHED @@ -690,47 +665,49 @@ io_work_loop: # _TIF_MCCK_PENDING is set, call handler # io_mcck_pending: + # TRACE_IRQS_ON already done at io_return l %r1,BASED(.Ls390_handle_mcck) basr %r14,%r1 # TIF bit will be cleared by handler - b BASED(io_work_loop) + TRACE_IRQS_OFF + b BASED(io_return) # # _TIF_NEED_RESCHED is set, call schedule # io_reschedule: - TRACE_IRQS_ON + # TRACE_IRQS_ON already done at io_return l %r1,BASED(.Lschedule) stosm __SF_EMPTY(%r15),0x03 # reenable interrupts basr %r14,%r1 # call scheduler stnsm __SF_EMPTY(%r15),0xfc # disable I/O and ext. interrupts TRACE_IRQS_OFF - b BASED(io_work_loop) + b BASED(io_return) # # _TIF_SIGPENDING 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 l %r1,BASED(.Ldo_signal) basr %r14,%r1 # call do_signal stnsm __SF_EMPTY(%r15),0xfc # disable I/O and ext. interrupts TRACE_IRQS_OFF - b BASED(io_work_loop) + b BASED(io_return) # # _TIF_SIGPENDING is set, call do_signal # 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 l %r1,BASED(.Ldo_notify_resume) basr %r14,%r1 # call do_signal stnsm __SF_EMPTY(%r15),0xfc # disable I/O and ext. interrupts TRACE_IRQS_OFF - b BASED(io_work_loop) + b BASED(io_return) /* * External interrupt handler routine @@ -918,14 +895,14 @@ stack_overflow: cleanup_table_system_call: .long system_call + 0x80000000, sysc_do_svc + 0x80000000 -cleanup_table_sysc_return: - .long sysc_return + 0x80000000, sysc_leave + 0x80000000 -cleanup_table_sysc_leave: - .long sysc_leave + 0x80000000, sysc_done + 0x80000000 -cleanup_table_io_return: - .long io_return + 0x80000000, io_leave + 0x80000000 -cleanup_table_io_leave: - .long io_leave + 0x80000000, io_done + 0x80000000 +cleanup_table_sysc_tif: + .long sysc_tif + 0x80000000, sysc_restore + 0x80000000 +cleanup_table_sysc_restore: + .long sysc_restore + 0x80000000, sysc_done + 0x80000000 +cleanup_table_io_tif: + .long io_tif + 0x80000000, io_restore + 0x80000000 +cleanup_table_io_restore: + .long io_restore + 0x80000000, io_done + 0x80000000 cleanup_critical: clc 4(4,%r12),BASED(cleanup_table_system_call) @@ -933,25 +910,25 @@ cleanup_critical: clc 4(4,%r12),BASED(cleanup_table_system_call+4) bl BASED(cleanup_system_call) 0: - clc 4(4,%r12),BASED(cleanup_table_sysc_return) + clc 4(4,%r12),BASED(cleanup_table_sysc_tif) bl BASED(0f) - clc 4(4,%r12),BASED(cleanup_table_sysc_return+4) - bl BASED(cleanup_sysc_return) + clc 4(4,%r12),BASED(cleanup_table_sysc_tif+4) + bl BASED(cleanup_sysc_tif) 0: - clc 4(4,%r12),BASED(cleanup_table_sysc_leave) + clc 4(4,%r12),BASED(cleanup_table_sysc_restore) bl BASED(0f) - clc 4(4,%r12),BASED(cleanup_table_sysc_leave+4) - bl BASED(cleanup_sysc_leave) + clc 4(4,%r12),BASED(cleanup_table_sysc_restore+4) + bl BASED(cleanup_sysc_restore) 0: - clc 4(4,%r12),BASED(cleanup_table_io_return) + clc 4(4,%r12),BASED(cleanup_table_io_tif) bl BASED(0f) - clc 4(4,%r12),BASED(cleanup_table_io_return+4) - bl BASED(cleanup_io_return) + clc 4(4,%r12),BASED(cleanup_table_io_tif+4) + bl BASED(cleanup_io_tif) 0: - clc 4(4,%r12),BASED(cleanup_table_io_leave) + clc 4(4,%r12),BASED(cleanup_table_io_restore) bl BASED(0f) - clc 4(4,%r12),BASED(cleanup_table_io_leave+4) - bl BASED(cleanup_io_leave) + clc 4(4,%r12),BASED(cleanup_table_io_restore+4) + bl BASED(cleanup_io_restore) 0: br %r14 @@ -998,17 +975,17 @@ cleanup_system_call_insn: .long sysc_stime + 0x80000000 .long sysc_update + 0x80000000 -cleanup_sysc_return: +cleanup_sysc_tif: mvc __LC_RETURN_PSW(4),0(%r12) - mvc __LC_RETURN_PSW+4(4),BASED(cleanup_table_sysc_return) + mvc __LC_RETURN_PSW+4(4),BASED(cleanup_table_sysc_tif) la %r12,__LC_RETURN_PSW br %r14 -cleanup_sysc_leave: - clc 4(4,%r12),BASED(cleanup_sysc_leave_insn) +cleanup_sysc_restore: + clc 4(4,%r12),BASED(cleanup_sysc_restore_insn) be BASED(2f) mvc __LC_EXIT_TIMER(8),__LC_ASYNC_ENTER_TIMER - clc 4(4,%r12),BASED(cleanup_sysc_leave_insn+4) + clc 4(4,%r12),BASED(cleanup_sysc_restore_insn+4) be BASED(2f) mvc __LC_RETURN_PSW(8),SP_PSW(%r15) c %r12,BASED(.Lmck_old_psw) @@ -1020,21 +997,21 @@ cleanup_sysc_leave: l %r15,SP_R15(%r15) 2: la %r12,__LC_RETURN_PSW br %r14 -cleanup_sysc_leave_insn: +cleanup_sysc_restore_insn: .long sysc_done - 4 + 0x80000000 .long sysc_done - 8 + 0x80000000 -cleanup_io_return: +cleanup_io_tif: mvc __LC_RETURN_PSW(4),0(%r12) - mvc __LC_RETURN_PSW+4(4),BASED(cleanup_table_io_return) + mvc __LC_RETURN_PSW+4(4),BASED(cleanup_table_io_tif) la %r12,__LC_RETURN_PSW br %r14 -cleanup_io_leave: - clc 4(4,%r12),BASED(cleanup_io_leave_insn) +cleanup_io_restore: + clc 4(4,%r12),BASED(cleanup_io_restore_insn) be BASED(2f) mvc __LC_EXIT_TIMER(8),__LC_ASYNC_ENTER_TIMER - clc 4(4,%r12),BASED(cleanup_io_leave_insn+4) + clc 4(4,%r12),BASED(cleanup_io_restore_insn+4) be BASED(2f) mvc __LC_RETURN_PSW(8),SP_PSW(%r15) c %r12,BASED(.Lmck_old_psw) @@ -1046,7 +1023,7 @@ cleanup_io_leave: l %r15,SP_R15(%r15) 2: la %r12,__LC_RETURN_PSW br %r14 -cleanup_io_leave_insn: +cleanup_io_restore_insn: .long io_done - 4 + 0x80000000 .long io_done - 8 + 0x80000000 -- cgit 1.4.1