diff options
Diffstat (limited to 'arch/csky/kernel')
-rw-r--r-- | arch/csky/kernel/Makefile | 2 | ||||
-rw-r--r-- | arch/csky/kernel/asm-offsets.c | 3 | ||||
-rw-r--r-- | arch/csky/kernel/dumpstack.c | 49 | ||||
-rw-r--r-- | arch/csky/kernel/entry.S | 129 | ||||
-rw-r--r-- | arch/csky/kernel/ftrace.c | 2 | ||||
-rw-r--r-- | arch/csky/kernel/perf_callchain.c | 9 | ||||
-rw-r--r-- | arch/csky/kernel/probes/uprobes.c | 5 | ||||
-rw-r--r-- | arch/csky/kernel/process.c | 37 | ||||
-rw-r--r-- | arch/csky/kernel/ptrace.c | 6 | ||||
-rw-r--r-- | arch/csky/kernel/setup.c | 26 | ||||
-rw-r--r-- | arch/csky/kernel/stacktrace.c | 176 |
11 files changed, 235 insertions, 209 deletions
diff --git a/arch/csky/kernel/Makefile b/arch/csky/kernel/Makefile index fd6d9dc8b7f3..37f37c0e934a 100644 --- a/arch/csky/kernel/Makefile +++ b/arch/csky/kernel/Makefile @@ -3,7 +3,7 @@ extra-y := head.o vmlinux.lds obj-y += entry.o atomic.o signal.o traps.o irq.o time.o vdso.o obj-y += power.o syscall.o syscall_table.o setup.o -obj-y += process.o cpu-probe.o ptrace.o dumpstack.o +obj-y += process.o cpu-probe.o ptrace.o stacktrace.o obj-y += probes/ obj-$(CONFIG_MODULES) += module.o diff --git a/arch/csky/kernel/asm-offsets.c b/arch/csky/kernel/asm-offsets.c index f8be348df9e4..17479860d43d 100644 --- a/arch/csky/kernel/asm-offsets.c +++ b/arch/csky/kernel/asm-offsets.c @@ -18,8 +18,7 @@ int main(void) DEFINE(TASK_ACTIVE_MM, offsetof(struct task_struct, active_mm)); /* offsets into the thread struct */ - DEFINE(THREAD_KSP, offsetof(struct thread_struct, ksp)); - DEFINE(THREAD_SR, offsetof(struct thread_struct, sr)); + DEFINE(THREAD_KSP, offsetof(struct thread_struct, sp)); DEFINE(THREAD_FESR, offsetof(struct thread_struct, user_fp.fesr)); DEFINE(THREAD_FCR, offsetof(struct thread_struct, user_fp.fcr)); DEFINE(THREAD_FPREG, offsetof(struct thread_struct, user_fp.vr)); diff --git a/arch/csky/kernel/dumpstack.c b/arch/csky/kernel/dumpstack.c deleted file mode 100644 index d67f9777cfd9..000000000000 --- a/arch/csky/kernel/dumpstack.c +++ /dev/null @@ -1,49 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0 -// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd. - -#include <linux/ptrace.h> - -int kstack_depth_to_print = 48; - -void show_trace(unsigned long *stack) -{ - unsigned long *stack_end; - unsigned long *stack_start; - unsigned long *fp; - unsigned long addr; - - addr = (unsigned long) stack & THREAD_MASK; - stack_start = (unsigned long *) addr; - stack_end = (unsigned long *) (addr + THREAD_SIZE); - - fp = stack; - pr_info("\nCall Trace:"); - - while (fp > stack_start && fp < stack_end) { -#ifdef CONFIG_STACKTRACE - addr = fp[1]; - fp = (unsigned long *) fp[0]; -#else - addr = *fp++; -#endif - if (__kernel_text_address(addr)) - pr_cont("\n[<%08lx>] %pS", addr, (void *)addr); - } - pr_cont("\n"); -} - -void show_stack(struct task_struct *task, unsigned long *stack) -{ - if (!stack) { - if (task) - stack = (unsigned long *)thread_saved_fp(task); - else -#ifdef CONFIG_STACKTRACE - asm volatile("mov %0, r8\n":"=r"(stack)::"memory"); -#else - stack = (unsigned long *)&stack; -#endif - } - - show_trace(stack); -} diff --git a/arch/csky/kernel/entry.S b/arch/csky/kernel/entry.S index 364819536f2e..f13800383a19 100644 --- a/arch/csky/kernel/entry.S +++ b/arch/csky/kernel/entry.S @@ -128,39 +128,41 @@ tlbop_end 1 ENTRY(csky_systemcall) SAVE_ALL TRAP0_SIZE zero_fp -#ifdef CONFIG_RSEQ_DEBUG - mov a0, sp - jbsr rseq_syscall -#endif psrset ee, ie - lrw r11, __NR_syscalls - cmphs syscallid, r11 /* Check nr of syscall */ - bt ret_from_exception + lrw r9, __NR_syscalls + cmphs syscallid, r9 /* Check nr of syscall */ + bt 1f - lrw r13, sys_call_table - ixw r13, syscallid - ldw r11, (r13) - cmpnei r11, 0 + lrw r9, sys_call_table + ixw r9, syscallid + ldw syscallid, (r9) + cmpnei syscallid, 0 bf ret_from_exception mov r9, sp bmaski r10, THREAD_SHIFT andn r9, r10 - ldw r12, (r9, TINFO_FLAGS) - ANDI_R3 r12, (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_TRACEPOINT | _TIF_SYSCALL_AUDIT) - cmpnei r12, 0 + ldw r10, (r9, TINFO_FLAGS) + lrw r9, _TIF_SYSCALL_WORK + and r10, r9 + cmpnei r10, 0 bt csky_syscall_trace #if defined(__CSKYABIV2__) subi sp, 8 stw r5, (sp, 0x4) stw r4, (sp, 0x0) - jsr r11 /* Do system call */ + jsr syscallid /* Do system call */ addi sp, 8 #else - jsr r11 + jsr syscallid #endif stw a0, (sp, LSAVE_A0) /* Save return value */ +1: +#ifdef CONFIG_DEBUG_RSEQ + mov a0, sp + jbsr rseq_syscall +#endif jmpi ret_from_exception csky_syscall_trace: @@ -173,18 +175,23 @@ csky_syscall_trace: ldw a3, (sp, LSAVE_A3) #if defined(__CSKYABIV2__) subi sp, 8 - stw r5, (sp, 0x4) - stw r4, (sp, 0x0) + ldw r9, (sp, LSAVE_A4) + stw r9, (sp, 0x0) + ldw r9, (sp, LSAVE_A5) + stw r9, (sp, 0x4) + jsr syscallid /* Do system call */ + addi sp, 8 #else ldw r6, (sp, LSAVE_A4) ldw r7, (sp, LSAVE_A5) -#endif - jsr r11 /* Do system call */ -#if defined(__CSKYABIV2__) - addi sp, 8 + jsr syscallid /* Do system call */ #endif stw a0, (sp, LSAVE_A0) /* Save return value */ +#ifdef CONFIG_DEBUG_RSEQ + mov a0, sp + jbsr rseq_syscall +#endif mov a0, sp /* right now, sp --> pt_regs */ jbsr syscall_trace_exit br ret_from_exception @@ -200,18 +207,20 @@ ENTRY(ret_from_fork) mov r9, sp bmaski r10, THREAD_SHIFT andn r9, r10 - ldw r12, (r9, TINFO_FLAGS) - ANDI_R3 r12, (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_TRACEPOINT | _TIF_SYSCALL_AUDIT) - cmpnei r12, 0 + ldw r10, (r9, TINFO_FLAGS) + lrw r9, _TIF_SYSCALL_WORK + and r10, r9 + cmpnei r10, 0 bf ret_from_exception mov a0, sp /* sp = pt_regs pointer */ jbsr syscall_trace_exit ret_from_exception: - ld syscallid, (sp, LSAVE_PSR) - btsti syscallid, 31 - bt 1f + psrclr ie + ld r9, (sp, LSAVE_PSR) + btsti r9, 31 + bt 1f /* * Load address of current->thread_info, Then get address of task_struct * Get task_needreshed in task_struct @@ -220,11 +229,24 @@ ret_from_exception: bmaski r10, THREAD_SHIFT andn r9, r10 - ldw r12, (r9, TINFO_FLAGS) - andi r12, (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_NEED_RESCHED | _TIF_UPROBE) - cmpnei r12, 0 + ldw r10, (r9, TINFO_FLAGS) + lrw r9, _TIF_WORK_MASK + and r10, r9 + cmpnei r10, 0 bt exit_work 1: +#ifdef CONFIG_PREEMPTION + mov r9, sp + bmaski r10, THREAD_SHIFT + andn r9, r10 + + ldw r10, (r9, TINFO_PREEMPT) + cmpnei r10, 0 + bt 2f + jbsr preempt_schedule_irq /* irq en/disable is done inside */ +2: +#endif + #ifdef CONFIG_TRACE_IRQFLAGS ld r10, (sp, LSAVE_PSR) btsti r10, 6 @@ -235,14 +257,15 @@ ret_from_exception: RESTORE_ALL exit_work: - lrw syscallid, ret_from_exception - mov lr, syscallid + lrw r9, ret_from_exception + mov lr, r9 - btsti r12, TIF_NEED_RESCHED + btsti r10, TIF_NEED_RESCHED bt work_resched + psrset ie mov a0, sp - mov a1, r12 + mov a1, r10 jmpi do_notify_resume work_resched: @@ -291,34 +314,10 @@ ENTRY(csky_irq) jbsr trace_hardirqs_off #endif -#ifdef CONFIG_PREEMPTION - mov r9, sp /* Get current stack pointer */ - bmaski r10, THREAD_SHIFT - andn r9, r10 /* Get thread_info */ - - /* - * Get task_struct->stack.preempt_count for current, - * and increase 1. - */ - ldw r12, (r9, TINFO_PREEMPT) - addi r12, 1 - stw r12, (r9, TINFO_PREEMPT) -#endif mov a0, sp jbsr csky_do_IRQ -#ifdef CONFIG_PREEMPTION - subi r12, 1 - stw r12, (r9, TINFO_PREEMPT) - cmpnei r12, 0 - bt 2f - ldw r12, (r9, TINFO_FLAGS) - btsti r12, TIF_NEED_RESCHED - bf 2f - jbsr preempt_schedule_irq /* irq en/disable is done inside */ -#endif -2: jmpi ret_from_exception /* @@ -330,11 +329,6 @@ ENTRY(__switch_to) lrw a3, TASK_THREAD addu a3, a0 - mfcr a2, psr /* Save PSR value */ - stw a2, (a3, THREAD_SR) /* Save PSR in task struct */ - bclri a2, 6 /* Disable interrupts */ - mtcr a2, psr - SAVE_SWITCH_STACK stw sp, (a3, THREAD_KSP) @@ -345,12 +339,9 @@ ENTRY(__switch_to) ldw sp, (a3, THREAD_KSP) /* Set next kernel sp */ - ldw a2, (a3, THREAD_SR) /* Set next PSR */ - mtcr a2, psr - #if defined(__CSKYABIV2__) - addi r7, a1, TASK_THREAD_INFO - ldw tls, (r7, TINFO_TP_VALUE) + addi a3, a1, TASK_THREAD_INFO + ldw tls, (a3, TINFO_TP_VALUE) #endif RESTORE_SWITCH_STACK diff --git a/arch/csky/kernel/ftrace.c b/arch/csky/kernel/ftrace.c index 44628e3f7fa6..3c425b84e3be 100644 --- a/arch/csky/kernel/ftrace.c +++ b/arch/csky/kernel/ftrace.c @@ -202,6 +202,7 @@ int ftrace_disable_ftrace_graph_caller(void) #endif /* CONFIG_DYNAMIC_FTRACE */ #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ +#ifdef CONFIG_DYNAMIC_FTRACE #ifndef CONFIG_CPU_HAS_ICACHE_INS struct ftrace_modify_param { int command; @@ -231,6 +232,7 @@ void arch_ftrace_update_code(int command) stop_machine(__ftrace_modify_code, ¶m, cpu_online_mask); } #endif +#endif /* CONFIG_DYNAMIC_FTRACE */ /* _mcount is defined in abi's mcount.S */ EXPORT_SYMBOL(_mcount); diff --git a/arch/csky/kernel/perf_callchain.c b/arch/csky/kernel/perf_callchain.c index e68ff375c8f8..ab55e98ee8f6 100644 --- a/arch/csky/kernel/perf_callchain.c +++ b/arch/csky/kernel/perf_callchain.c @@ -12,12 +12,17 @@ struct stackframe { static int unwind_frame_kernel(struct stackframe *frame) { - if (kstack_end((void *)frame->fp)) + unsigned long low = (unsigned long)task_stack_page(current); + unsigned long high = low + THREAD_SIZE; + + if (unlikely(frame->fp < low || frame->fp > high)) return -EPERM; - if (frame->fp & 0x3 || frame->fp < TASK_SIZE) + + if (kstack_end((void *)frame->fp) || frame->fp & 0x3) return -EPERM; *frame = *(struct stackframe *)frame->fp; + if (__kernel_text_address(frame->lr)) { int graph = 0; diff --git a/arch/csky/kernel/probes/uprobes.c b/arch/csky/kernel/probes/uprobes.c index b3a56c260e3e..1a9e0961b2b5 100644 --- a/arch/csky/kernel/probes/uprobes.c +++ b/arch/csky/kernel/probes/uprobes.c @@ -11,6 +11,11 @@ #define UPROBE_TRAP_NR UINT_MAX +bool is_swbp_insn(uprobe_opcode_t *insn) +{ + return (*insn & 0xffff) == UPROBE_SWBP_INSN; +} + unsigned long uprobe_get_swbp_addr(struct pt_regs *regs) { return instruction_pointer(regs); diff --git a/arch/csky/kernel/process.c b/arch/csky/kernel/process.c index f7b231ca269a..8b3fad062ab2 100644 --- a/arch/csky/kernel/process.c +++ b/arch/csky/kernel/process.c @@ -35,7 +35,7 @@ void flush_thread(void){} */ unsigned long thread_saved_pc(struct task_struct *tsk) { - struct switch_stack *sw = (struct switch_stack *)tsk->thread.ksp; + struct switch_stack *sw = (struct switch_stack *)tsk->thread.sp; return sw->r15; } @@ -56,8 +56,8 @@ int copy_thread_tls(unsigned long clone_flags, childstack = ((struct switch_stack *) childregs) - 1; memset(childstack, 0, sizeof(struct switch_stack)); - /* setup ksp for switch_to !!! */ - p->thread.ksp = (unsigned long)childstack; + /* setup thread.sp for switch_to !!! */ + p->thread.sp = (unsigned long)childstack; if (unlikely(p->flags & PF_KTHREAD)) { memset(childregs, 0, sizeof(struct pt_regs)); @@ -98,37 +98,6 @@ int dump_task_regs(struct task_struct *tsk, elf_gregset_t *pr_regs) return 1; } -unsigned long get_wchan(struct task_struct *p) -{ - unsigned long lr; - unsigned long *fp, *stack_start, *stack_end; - int count = 0; - - if (!p || p == current || p->state == TASK_RUNNING) - return 0; - - stack_start = (unsigned long *)end_of_stack(p); - stack_end = (unsigned long *)(task_stack_page(p) + THREAD_SIZE); - - fp = (unsigned long *) thread_saved_fp(p); - do { - if (fp < stack_start || fp > stack_end) - return 0; -#ifdef CONFIG_STACKTRACE - lr = fp[1]; - fp = (unsigned long *)fp[0]; -#else - lr = *fp++; -#endif - if (!in_sched_functions(lr) && - __kernel_text_address(lr)) - return lr; - } while (count++ < 16); - - return 0; -} -EXPORT_SYMBOL(get_wchan); - #ifndef CONFIG_CPU_PM_NONE void arch_cpu_idle(void) { diff --git a/arch/csky/kernel/ptrace.c b/arch/csky/kernel/ptrace.c index 21ac2608f205..5a82230bddf9 100644 --- a/arch/csky/kernel/ptrace.c +++ b/arch/csky/kernel/ptrace.c @@ -41,6 +41,9 @@ static void singlestep_disable(struct task_struct *tsk) regs = task_pt_regs(tsk); regs->sr = (regs->sr & TRACE_MODE_MASK) | TRACE_MODE_RUN; + + /* Enable irq */ + regs->sr |= BIT(6); } static void singlestep_enable(struct task_struct *tsk) @@ -49,6 +52,9 @@ static void singlestep_enable(struct task_struct *tsk) regs = task_pt_regs(tsk); regs->sr = (regs->sr & TRACE_MODE_MASK) | TRACE_MODE_SI; + + /* Disable irq */ + regs->sr &= ~BIT(6); } /* diff --git a/arch/csky/kernel/setup.c b/arch/csky/kernel/setup.c index 819a9a7bf786..0481f4e34538 100644 --- a/arch/csky/kernel/setup.c +++ b/arch/csky/kernel/setup.c @@ -26,7 +26,9 @@ struct screen_info screen_info = { static void __init csky_memblock_init(void) { - unsigned long zone_size[MAX_NR_ZONES]; + unsigned long lowmem_size = PFN_DOWN(LOWMEM_LIMIT - PHYS_OFFSET_OFFSET); + unsigned long sseg_size = PFN_DOWN(SSEG_SIZE - PHYS_OFFSET_OFFSET); + unsigned long max_zone_pfn[MAX_NR_ZONES] = { 0 }; signed long size; memblock_reserve(__pa(_stext), _end - _stext); @@ -36,28 +38,22 @@ static void __init csky_memblock_init(void) memblock_dump_all(); - memset(zone_size, 0, sizeof(zone_size)); - min_low_pfn = PFN_UP(memblock_start_of_DRAM()); max_low_pfn = max_pfn = PFN_DOWN(memblock_end_of_DRAM()); size = max_pfn - min_low_pfn; - if (size <= PFN_DOWN(SSEG_SIZE - PHYS_OFFSET_OFFSET)) - zone_size[ZONE_NORMAL] = size; - else if (size < PFN_DOWN(LOWMEM_LIMIT - PHYS_OFFSET_OFFSET)) { - zone_size[ZONE_NORMAL] = - PFN_DOWN(SSEG_SIZE - PHYS_OFFSET_OFFSET); - max_low_pfn = min_low_pfn + zone_size[ZONE_NORMAL]; - } else { - zone_size[ZONE_NORMAL] = - PFN_DOWN(LOWMEM_LIMIT - PHYS_OFFSET_OFFSET); - max_low_pfn = min_low_pfn + zone_size[ZONE_NORMAL]; + if (size >= lowmem_size) { + max_low_pfn = min_low_pfn + lowmem_size; write_mmu_msa1(read_mmu_msa0() + SSEG_SIZE); + } else if (size > sseg_size) { + max_low_pfn = min_low_pfn + sseg_size; } + max_zone_pfn[ZONE_NORMAL] = max_low_pfn; + #ifdef CONFIG_HIGHMEM - zone_size[ZONE_HIGHMEM] = max_pfn - max_low_pfn; + max_zone_pfn[ZONE_HIGHMEM] = max_pfn; highstart_pfn = max_low_pfn; highend_pfn = max_pfn; @@ -66,7 +62,7 @@ static void __init csky_memblock_init(void) dma_contiguous_reserve(0); - free_area_init_node(0, zone_size, min_low_pfn, NULL); + free_area_init(max_zone_pfn); } void __init setup_arch(char **cmdline_p) diff --git a/arch/csky/kernel/stacktrace.c b/arch/csky/kernel/stacktrace.c index fec777a643f1..92809e1da723 100644 --- a/arch/csky/kernel/stacktrace.c +++ b/arch/csky/kernel/stacktrace.c @@ -1,57 +1,159 @@ // SPDX-License-Identifier: GPL-2.0 -/* Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd. */ #include <linux/sched/debug.h> #include <linux/sched/task_stack.h> #include <linux/stacktrace.h> #include <linux/ftrace.h> +#include <linux/ptrace.h> -void save_stack_trace(struct stack_trace *trace) +#ifdef CONFIG_FRAME_POINTER + +struct stackframe { + unsigned long fp; + unsigned long ra; +}; + +void notrace walk_stackframe(struct task_struct *task, struct pt_regs *regs, + bool (*fn)(unsigned long, void *), void *arg) { - save_stack_trace_tsk(current, trace); + unsigned long fp, sp, pc; + + if (regs) { + fp = frame_pointer(regs); + sp = user_stack_pointer(regs); + pc = instruction_pointer(regs); + } else if (task == NULL || task == current) { + const register unsigned long current_sp __asm__ ("sp"); + const register unsigned long current_fp __asm__ ("r8"); + fp = current_fp; + sp = current_sp; + pc = (unsigned long)walk_stackframe; + } else { + /* task blocked in __switch_to */ + fp = thread_saved_fp(task); + sp = thread_saved_sp(task); + pc = thread_saved_lr(task); + } + + for (;;) { + unsigned long low, high; + struct stackframe *frame; + + if (unlikely(!__kernel_text_address(pc) || fn(pc, arg))) + break; + + /* Validate frame pointer */ + low = sp; + high = ALIGN(sp, THREAD_SIZE); + if (unlikely(fp < low || fp > high || fp & 0x3)) + break; + /* Unwind stack frame */ + frame = (struct stackframe *)fp; + sp = fp; + fp = frame->fp; + pc = ftrace_graph_ret_addr(current, NULL, frame->ra, + (unsigned long *)(fp - 8)); + } } -EXPORT_SYMBOL_GPL(save_stack_trace); -void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace) +#else /* !CONFIG_FRAME_POINTER */ + +static void notrace walk_stackframe(struct task_struct *task, + struct pt_regs *regs, bool (*fn)(unsigned long, void *), void *arg) { - unsigned long *fp, *stack_start, *stack_end; - unsigned long addr; - int skip = trace->skip; - int savesched; - int graph_idx = 0; + unsigned long sp, pc; + unsigned long *ksp; - if (tsk == current) { - asm volatile("mov %0, r8\n":"=r"(fp)); - savesched = 1; + if (regs) { + sp = user_stack_pointer(regs); + pc = instruction_pointer(regs); + } else if (task == NULL || task == current) { + const register unsigned long current_sp __asm__ ("sp"); + sp = current_sp; + pc = (unsigned long)walk_stackframe; } else { - fp = (unsigned long *)thread_saved_fp(tsk); - savesched = 0; + /* task blocked in __switch_to */ + sp = thread_saved_sp(task); + pc = thread_saved_lr(task); } - addr = (unsigned long) fp & THREAD_MASK; - stack_start = (unsigned long *) addr; - stack_end = (unsigned long *) (addr + THREAD_SIZE); - - while (fp > stack_start && fp < stack_end) { - unsigned long lpp, fpp; + if (unlikely(sp & 0x3)) + return; - fpp = fp[0]; - lpp = fp[1]; - if (!__kernel_text_address(lpp)) + ksp = (unsigned long *)sp; + while (!kstack_end(ksp)) { + if (__kernel_text_address(pc) && unlikely(fn(pc, arg))) break; - else - lpp = ftrace_graph_ret_addr(tsk, &graph_idx, lpp, NULL); - - if (savesched || !in_sched_functions(lpp)) { - if (skip) { - skip--; - } else { - trace->entries[trace->nr_entries++] = lpp; - if (trace->nr_entries >= trace->max_entries) - break; - } - } - fp = (unsigned long *)fpp; + pc = (*ksp++) - 0x4; } } +#endif /* CONFIG_FRAME_POINTER */ + +static bool print_trace_address(unsigned long pc, void *arg) +{ + print_ip_sym(pc); + return false; +} + +void show_stack(struct task_struct *task, unsigned long *sp) +{ + pr_cont("Call Trace:\n"); + walk_stackframe(task, NULL, print_trace_address, NULL); +} + +static bool save_wchan(unsigned long pc, void *arg) +{ + if (!in_sched_functions(pc)) { + unsigned long *p = arg; + *p = pc; + return true; + } + return false; +} + +unsigned long get_wchan(struct task_struct *task) +{ + unsigned long pc = 0; + + if (likely(task && task != current && task->state != TASK_RUNNING)) + walk_stackframe(task, NULL, save_wchan, &pc); + return pc; +} + +#ifdef CONFIG_STACKTRACE +static bool __save_trace(unsigned long pc, void *arg, bool nosched) +{ + struct stack_trace *trace = arg; + + if (unlikely(nosched && in_sched_functions(pc))) + return false; + if (unlikely(trace->skip > 0)) { + trace->skip--; + return false; + } + + trace->entries[trace->nr_entries++] = pc; + return (trace->nr_entries >= trace->max_entries); +} + +static bool save_trace(unsigned long pc, void *arg) +{ + return __save_trace(pc, arg, false); +} + +/* + * Save stack-backtrace addresses into a stack_trace buffer. + */ +void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace) +{ + walk_stackframe(tsk, NULL, save_trace, trace); +} EXPORT_SYMBOL_GPL(save_stack_trace_tsk); + +void save_stack_trace(struct stack_trace *trace) +{ + save_stack_trace_tsk(NULL, trace); +} +EXPORT_SYMBOL_GPL(save_stack_trace); + +#endif /* CONFIG_STACKTRACE */ |