From 3a51d50f426cbb65add424baebe511dcf5ac45cc Mon Sep 17 00:00:00 2001 From: Vineet Gupta Date: Wed, 10 Jul 2013 16:03:45 +0200 Subject: ARC: Make arc_unwind_core accessible externally The arc unwinder can also be used for perf callchains. Signed-off-by: Mischa Jonker Signed-off-by: Vineet Gupta --- arch/arc/kernel/stacktrace.c | 15 ++++++++++++++- 1 file changed, 14 insertions(+), 1 deletion(-) (limited to 'arch/arc/kernel') diff --git a/arch/arc/kernel/stacktrace.c b/arch/arc/kernel/stacktrace.c index 9ce47cfe2303..6492507a3d74 100644 --- a/arch/arc/kernel/stacktrace.c +++ b/arch/arc/kernel/stacktrace.c @@ -43,6 +43,10 @@ static void seed_unwind_frame_info(struct task_struct *tsk, struct pt_regs *regs, struct unwind_frame_info *frame_info) { + /* + * synchronous unwinding (e.g. dump_stack) + * - uses current values of SP and friends + */ if (tsk == NULL && regs == NULL) { unsigned long fp, sp, blink, ret; frame_info->task = current; @@ -61,6 +65,11 @@ static void seed_unwind_frame_info(struct task_struct *tsk, frame_info->regs.r63 = ret; frame_info->call_frame = 0; } else if (regs == NULL) { + /* + * Asynchronous unwinding of sleeping task + * - Gets SP etc from task's pt_regs (saved bottom of kernel + * mode stack of task) + */ frame_info->task = tsk; @@ -83,6 +92,10 @@ static void seed_unwind_frame_info(struct task_struct *tsk, frame_info->call_frame = 0; } else { + /* + * Asynchronous unwinding of intr/exception + * - Just uses the pt_regs passed + */ frame_info->task = tsk; frame_info->regs.r27 = regs->fp; @@ -95,7 +108,7 @@ static void seed_unwind_frame_info(struct task_struct *tsk, #endif -static noinline unsigned int +notrace noinline unsigned int arc_unwind_core(struct task_struct *tsk, struct pt_regs *regs, int (*consumer_fn) (unsigned int, void *), void *arg) { -- cgit v1.2.3 From ceed97ab4ff76cb5b1d616a810e941f8837dc440 Mon Sep 17 00:00:00 2001 From: Vineet Gupta Date: Thu, 2 Oct 2014 12:30:42 +0530 Subject: ARC: perf: Enable generic software events Signed-off-by: Vineet Gupta --- arch/arc/kernel/unaligned.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'arch/arc/kernel') diff --git a/arch/arc/kernel/unaligned.c b/arch/arc/kernel/unaligned.c index 7ff5b5c183bb..74db59b6f392 100644 --- a/arch/arc/kernel/unaligned.c +++ b/arch/arc/kernel/unaligned.c @@ -12,6 +12,7 @@ */ #include +#include #include #include #include @@ -253,6 +254,7 @@ int misaligned_fixup(unsigned long address, struct pt_regs *regs, } } + perf_sw_event(PERF_COUNT_SW_ALIGNMENT_FAULTS, 1, regs, address); return 0; fault: -- cgit v1.2.3 From 13648b0118a24f4fc76c34e6c7b6ccf447e46a2a Mon Sep 17 00:00:00 2001 From: Vineet Gupta Date: Fri, 27 Feb 2015 10:39:17 +0530 Subject: ARC: Fix KSTK_ESP() /proc//maps currently don't annotate stack vma with "[stack]" This is because KSTK_ESP ie expected to return usermode SP of tsk while currently it returns the kernel mode SP of a sleeping tsk. While the fix is trivial, we also need to adjust the ARC kernel stack unwinder to not use KSTK_SP and friends any more. Cc: Reported-and-suggested-by: Alexey Brodkin Signed-off-by: Vineet Gupta --- arch/arc/kernel/stacktrace.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'arch/arc/kernel') diff --git a/arch/arc/kernel/stacktrace.c b/arch/arc/kernel/stacktrace.c index 6492507a3d74..92320d6f737c 100644 --- a/arch/arc/kernel/stacktrace.c +++ b/arch/arc/kernel/stacktrace.c @@ -73,9 +73,9 @@ static void seed_unwind_frame_info(struct task_struct *tsk, frame_info->task = tsk; - frame_info->regs.r27 = KSTK_FP(tsk); - frame_info->regs.r28 = KSTK_ESP(tsk); - frame_info->regs.r31 = KSTK_BLINK(tsk); + frame_info->regs.r27 = TSK_K_FP(tsk); + frame_info->regs.r28 = TSK_K_ESP(tsk); + frame_info->regs.r31 = TSK_K_BLINK(tsk); frame_info->regs.r63 = (unsigned int)__switch_to; /* In the prologue of __switch_to, first FP is saved on stack -- cgit v1.2.3 From 3240dd57e533da94998029af6e17008a1806c665 Mon Sep 17 00:00:00 2001 From: Vineet Gupta Date: Fri, 27 Feb 2015 10:59:31 +0530 Subject: ARC: Fix thread_saved_pc() The old implementation assumed that SP at the time of __switch_to() is right above pt_regs which is almost certainly not the case as there will be some stack build up between entry into kernel and leading up to __switch_to Signed-off-by: Vineet Gupta --- arch/arc/kernel/process.c | 23 ----------------------- 1 file changed, 23 deletions(-) (limited to 'arch/arc/kernel') diff --git a/arch/arc/kernel/process.c b/arch/arc/kernel/process.c index fdd89715d2d3..98c00a2d4dd9 100644 --- a/arch/arc/kernel/process.c +++ b/arch/arc/kernel/process.c @@ -192,29 +192,6 @@ int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fpu) return 0; } -/* - * API: expected by schedular Code: If thread is sleeping where is that. - * What is this good for? it will be always the scheduler or ret_from_fork. - * So we hard code that anyways. - */ -unsigned long thread_saved_pc(struct task_struct *t) -{ - struct pt_regs *regs = task_pt_regs(t); - unsigned long blink = 0; - - /* - * If the thread being queried for in not itself calling this, then it - * implies it is not executing, which in turn implies it is sleeping, - * which in turn implies it got switched OUT by the schedular. - * In that case, it's kernel mode blink can reliably retrieved as per - * the picture above (right above pt_regs). - */ - if (t != current && t->state != TASK_RUNNING) - blink = *((unsigned int *)regs - 1); - - return blink; -} - int elf_check_arch(const struct elf32_hdr *x) { unsigned int eflags; -- cgit v1.2.3