diff options
Diffstat (limited to 'arch/s390')
-rw-r--r-- | arch/s390/Kconfig | 8 | ||||
-rw-r--r-- | arch/s390/Kconfig.debug | 4 | ||||
-rw-r--r-- | arch/s390/Makefile | 5 | ||||
-rw-r--r-- | arch/s390/kernel/Makefile | 1 | ||||
-rw-r--r-- | arch/s390/kernel/entry.S | 29 | ||||
-rw-r--r-- | arch/s390/kernel/entry64.S | 21 | ||||
-rw-r--r-- | arch/s390/kernel/irq.c | 8 | ||||
-rw-r--r-- | arch/s390/kernel/process.c | 1 | ||||
-rw-r--r-- | arch/s390/kernel/stacktrace.c | 90 |
9 files changed, 158 insertions, 9 deletions
diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig index 821a141889de..224fbff79969 100644 --- a/arch/s390/Kconfig +++ b/arch/s390/Kconfig @@ -7,6 +7,14 @@ config MMU bool default y +config LOCKDEP_SUPPORT + bool + default y + +config STACKTRACE_SUPPORT + bool + default y + config RWSEM_GENERIC_SPINLOCK bool diff --git a/arch/s390/Kconfig.debug b/arch/s390/Kconfig.debug index f53b6d5300e5..2283933a9a93 100644 --- a/arch/s390/Kconfig.debug +++ b/arch/s390/Kconfig.debug @@ -1,5 +1,9 @@ menu "Kernel hacking" +config TRACE_IRQFLAGS_SUPPORT + bool + default y + source "lib/Kconfig.debug" endmenu diff --git a/arch/s390/Makefile b/arch/s390/Makefile index b3791fb094a8..74ef57dcfa60 100644 --- a/arch/s390/Makefile +++ b/arch/s390/Makefile @@ -34,6 +34,11 @@ cflags-$(CONFIG_MARCH_G5) += $(call cc-option,-march=g5) cflags-$(CONFIG_MARCH_Z900) += $(call cc-option,-march=z900) cflags-$(CONFIG_MARCH_Z990) += $(call cc-option,-march=z990) +# +# Prevent tail-call optimizations, to get clearer backtraces: +# +cflags-$(CONFIG_FRAME_POINTER) += -fno-optimize-sibling-calls + # old style option for packed stacks ifeq ($(call cc-option-yn,-mkernel-backchain),y) cflags-$(CONFIG_PACK_STACK) += -mkernel-backchain -D__PACK_STACK diff --git a/arch/s390/kernel/Makefile b/arch/s390/kernel/Makefile index 9269b5788fac..eabf00a6f770 100644 --- a/arch/s390/kernel/Makefile +++ b/arch/s390/kernel/Makefile @@ -21,6 +21,7 @@ obj-$(CONFIG_COMPAT) += compat_linux.o compat_signal.o \ obj-$(CONFIG_BINFMT_ELF32) += binfmt_elf32.o obj-$(CONFIG_VIRT_TIMER) += vtime.o +obj-$(CONFIG_STACKTRACE) += stacktrace.o # Kexec part S390_KEXEC_OBJS := machine_kexec.o crash.o diff --git a/arch/s390/kernel/entry.S b/arch/s390/kernel/entry.S index d8948c342caf..5b5799ac8f83 100644 --- a/arch/s390/kernel/entry.S +++ b/arch/s390/kernel/entry.S @@ -58,6 +58,21 @@ STACK_SIZE = 1 << STACK_SHIFT #define BASED(name) name-system_call(%r13) +#ifdef CONFIG_TRACE_IRQFLAGS + .macro TRACE_IRQS_ON + l %r1,BASED(.Ltrace_irq_on) + basr %r14,%r1 + .endm + + .macro TRACE_IRQS_OFF + l %r1,BASED(.Ltrace_irq_off) + basr %r14,%r1 + .endm +#else +#define TRACE_IRQS_ON +#define TRACE_IRQS_OFF +#endif + /* * Register usage in interrupt handlers: * R9 - pointer to current task structure @@ -361,6 +376,7 @@ ret_from_fork: st %r15,SP_R15(%r15) # store stack pointer for new kthread 0: l %r1,BASED(.Lschedtail) basr %r14,%r1 + TRACE_IRQS_ON stosm __SF_EMPTY(%r15),0x03 # reenable interrupts b BASED(sysc_return) @@ -516,6 +532,7 @@ pgm_no_vtime3: 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 + TRACE_IRQS_ON stosm __SF_EMPTY(%r15),0x03 # reenable interrupts b BASED(sysc_do_svc) @@ -539,9 +556,11 @@ io_int_handler: io_no_vtime: #endif l %r9,__LC_THREAD_INFO # load pointer to thread_info struct + TRACE_IRQS_OFF 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 + TRACE_IRQS_ON io_return: tm SP_PSW+1(%r15),0x01 # returning to user ? @@ -651,10 +670,12 @@ ext_int_handler: ext_no_vtime: #endif l %r9,__LC_THREAD_INFO # load pointer to thread_info struct + TRACE_IRQS_OFF la %r2,SP_PTREGS(%r15) # address of register-save area lh %r3,__LC_EXT_INT_CODE # get interruption code l %r1,BASED(.Ldo_extint) basr %r14,%r1 + TRACE_IRQS_ON b BASED(io_return) __critical_end: @@ -731,8 +752,10 @@ mcck_no_vtime: stosm __SF_EMPTY(%r15),0x04 # turn dat on tm __TI_flags+3(%r9),_TIF_MCCK_PENDING bno BASED(mcck_return) + TRACE_IRQS_OFF l %r1,BASED(.Ls390_handle_mcck) basr %r14,%r1 # call machine check handler + TRACE_IRQS_ON mcck_return: mvc __LC_RETURN_MCCK_PSW(8),SP_PSW(%r15) # move return PSW ni __LC_RETURN_MCCK_PSW+1,0xfd # clear wait state bit @@ -1012,7 +1035,11 @@ cleanup_io_leave_insn: .Lvfork: .long sys_vfork .Lschedtail: .long schedule_tail .Lsysc_table: .long sys_call_table - +#ifdef CONFIG_TRACE_IRQFLAGS +.Ltrace_irq_on:.long trace_hardirqs_on +.Ltrace_irq_off: + .long trace_hardirqs_off +#endif .Lcritical_start: .long __critical_start + 0x80000000 .Lcritical_end: diff --git a/arch/s390/kernel/entry64.S b/arch/s390/kernel/entry64.S index 1ca499fa54b4..56f5f613b868 100644 --- a/arch/s390/kernel/entry64.S +++ b/arch/s390/kernel/entry64.S @@ -58,6 +58,19 @@ _TIF_WORK_INT = (_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK | _TIF_NEED_RESCHED | \ #define BASED(name) name-system_call(%r13) +#ifdef CONFIG_TRACE_IRQFLAGS + .macro TRACE_IRQS_ON + brasl %r14,trace_hardirqs_on + .endm + + .macro TRACE_IRQS_OFF + brasl %r14,trace_hardirqs_off + .endm +#else +#define TRACE_IRQS_ON +#define TRACE_IRQS_OFF +#endif + .macro STORE_TIMER lc_offset #ifdef CONFIG_VIRT_CPU_ACCOUNTING stpt \lc_offset @@ -354,6 +367,7 @@ ret_from_fork: jo 0f stg %r15,SP_R15(%r15) # store stack pointer for new kthread 0: brasl %r14,schedule_tail + TRACE_IRQS_ON stosm 24(%r15),0x03 # reenable interrupts j sysc_return @@ -535,6 +549,7 @@ pgm_no_vtime3: mvc __THREAD_per+__PER_address(8,%r1),__LC_PER_ADDRESS mvc __THREAD_per+__PER_access_id(1,%r1),__LC_PER_ACCESS_ID oi __TI_flags+7(%r9),_TIF_SINGLE_STEP # set TIF_SINGLE_STEP + TRACE_IRQS_ON stosm __SF_EMPTY(%r15),0x03 # reenable interrupts j sysc_do_svc @@ -557,8 +572,10 @@ io_int_handler: io_no_vtime: #endif lg %r9,__LC_THREAD_INFO # load pointer to thread_info struct + TRACE_IRQS_OFF la %r2,SP_PTREGS(%r15) # address of register-save area brasl %r14,do_IRQ # call standard irq handler + TRACE_IRQS_ON io_return: tm SP_PSW+1(%r15),0x01 # returning to user ? @@ -665,9 +682,11 @@ ext_int_handler: ext_no_vtime: #endif lg %r9,__LC_THREAD_INFO # load pointer to thread_info struct + TRACE_IRQS_OFF la %r2,SP_PTREGS(%r15) # address of register-save area llgh %r3,__LC_EXT_INT_CODE # get interruption code brasl %r14,do_extint + TRACE_IRQS_ON j io_return __critical_end: @@ -743,7 +762,9 @@ mcck_no_vtime: stosm __SF_EMPTY(%r15),0x04 # turn dat on tm __TI_flags+7(%r9),_TIF_MCCK_PENDING jno mcck_return + TRACE_IRQS_OFF brasl %r14,s390_handle_mcck + TRACE_IRQS_ON mcck_return: mvc __LC_RETURN_MCCK_PSW(16),SP_PSW(%r15) # move return PSW ni __LC_RETURN_MCCK_PSW+1,0xfd # clear wait state bit diff --git a/arch/s390/kernel/irq.c b/arch/s390/kernel/irq.c index 480b6a5fef3a..1eef50918615 100644 --- a/arch/s390/kernel/irq.c +++ b/arch/s390/kernel/irq.c @@ -69,10 +69,6 @@ asmlinkage void do_softirq(void) local_irq_save(flags); - account_system_vtime(current); - - local_bh_disable(); - if (local_softirq_pending()) { /* Get current stack pointer. */ asm volatile("la %0,0(15)" : "=a" (old)); @@ -95,10 +91,6 @@ asmlinkage void do_softirq(void) __do_softirq(); } - account_system_vtime(current); - - __local_bh_enable(); - local_irq_restore(flags); } diff --git a/arch/s390/kernel/process.c b/arch/s390/kernel/process.c index 1f9399191794..78c8e5548caf 100644 --- a/arch/s390/kernel/process.c +++ b/arch/s390/kernel/process.c @@ -142,6 +142,7 @@ static void default_idle(void) return; } + trace_hardirqs_on(); /* Wait for external, I/O or machine check interrupt. */ __load_psw_mask(PSW_KERNEL_BITS | PSW_MASK_WAIT | PSW_MASK_IO | PSW_MASK_EXT); diff --git a/arch/s390/kernel/stacktrace.c b/arch/s390/kernel/stacktrace.c new file mode 100644 index 000000000000..de83f38288d0 --- /dev/null +++ b/arch/s390/kernel/stacktrace.c @@ -0,0 +1,90 @@ +/* + * arch/s390/kernel/stacktrace.c + * + * Stack trace management functions + * + * Copyright (C) IBM Corp. 2006 + * Author(s): Heiko Carstens <heiko.carstens@de.ibm.com> + */ + +#include <linux/sched.h> +#include <linux/stacktrace.h> +#include <linux/kallsyms.h> + +static inline unsigned long save_context_stack(struct stack_trace *trace, + unsigned int *skip, + unsigned long sp, + unsigned long low, + unsigned long high) +{ + struct stack_frame *sf; + struct pt_regs *regs; + unsigned long addr; + + while(1) { + sp &= PSW_ADDR_INSN; + if (sp < low || sp > high) + return sp; + sf = (struct stack_frame *)sp; + while(1) { + addr = sf->gprs[8] & PSW_ADDR_INSN; + if (!(*skip)) + trace->entries[trace->nr_entries++] = addr; + else + (*skip)--; + if (trace->nr_entries >= trace->max_entries) + return sp; + low = sp; + sp = sf->back_chain & PSW_ADDR_INSN; + if (!sp) + break; + if (sp <= low || sp > high - sizeof(*sf)) + return sp; + sf = (struct stack_frame *)sp; + } + /* Zero backchain detected, check for interrupt frame. */ + sp = (unsigned long)(sf + 1); + if (sp <= low || sp > high - sizeof(*regs)) + return sp; + regs = (struct pt_regs *)sp; + addr = regs->psw.addr & PSW_ADDR_INSN; + if (!(*skip)) + trace->entries[trace->nr_entries++] = addr; + else + (*skip)--; + if (trace->nr_entries >= trace->max_entries) + return sp; + low = sp; + sp = regs->gprs[15]; + } +} + +void save_stack_trace(struct stack_trace *trace, + struct task_struct *task, int all_contexts, + unsigned int skip) +{ + register unsigned long sp asm ("15"); + unsigned long orig_sp; + + sp &= PSW_ADDR_INSN; + orig_sp = sp; + + sp = save_context_stack(trace, &skip, sp, + S390_lowcore.panic_stack - PAGE_SIZE, + S390_lowcore.panic_stack); + if ((sp != orig_sp) && !all_contexts) + return; + sp = save_context_stack(trace, &skip, sp, + S390_lowcore.async_stack - ASYNC_SIZE, + S390_lowcore.async_stack); + if ((sp != orig_sp) && !all_contexts) + return; + if (task) + save_context_stack(trace, &skip, sp, + (unsigned long) task_stack_page(task), + (unsigned long) task_stack_page(task) + THREAD_SIZE); + else + save_context_stack(trace, &skip, sp, S390_lowcore.thread_info, + S390_lowcore.thread_info + THREAD_SIZE); + return; +} |