diff options
author | Daniel Vetter <daniel.vetter@ffwll.ch> | 2016-10-25 10:06:04 +0200 |
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committer | Daniel Vetter <daniel.vetter@ffwll.ch> | 2016-10-25 10:06:04 +0200 |
commit | 0fc4f78f44e6c6148cee32456f0d0023ec1c1fd8 (patch) | |
tree | 71c906207227dd8753a0191db9304035ec3471a4 /arch/x86/kernel/unwind_guess.c | |
parent | 78010cd9736ec571796f4404524ed575b81238b9 (diff) | |
parent | 5481e27f6fd06b7cb902072e81d6b083db8155eb (diff) |
Merge remote-tracking branch 'airlied/drm-next' into topic/drm-misc
Backmerge latest drm-next to have a baseline for the
s/fence/dma_fence/ patch from Chris.
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Diffstat (limited to 'arch/x86/kernel/unwind_guess.c')
-rw-r--r-- | arch/x86/kernel/unwind_guess.c | 53 |
1 files changed, 53 insertions, 0 deletions
diff --git a/arch/x86/kernel/unwind_guess.c b/arch/x86/kernel/unwind_guess.c new file mode 100644 index 000000000000..9298993dc8b7 --- /dev/null +++ b/arch/x86/kernel/unwind_guess.c @@ -0,0 +1,53 @@ +#include <linux/sched.h> +#include <linux/ftrace.h> +#include <asm/ptrace.h> +#include <asm/bitops.h> +#include <asm/stacktrace.h> +#include <asm/unwind.h> + +unsigned long unwind_get_return_address(struct unwind_state *state) +{ + if (unwind_done(state)) + return 0; + + return ftrace_graph_ret_addr(state->task, &state->graph_idx, + *state->sp, state->sp); +} +EXPORT_SYMBOL_GPL(unwind_get_return_address); + +bool unwind_next_frame(struct unwind_state *state) +{ + struct stack_info *info = &state->stack_info; + + if (unwind_done(state)) + return false; + + do { + for (state->sp++; state->sp < info->end; state->sp++) + if (__kernel_text_address(*state->sp)) + return true; + + state->sp = info->next_sp; + + } while (!get_stack_info(state->sp, state->task, info, + &state->stack_mask)); + + return false; +} +EXPORT_SYMBOL_GPL(unwind_next_frame); + +void __unwind_start(struct unwind_state *state, struct task_struct *task, + struct pt_regs *regs, unsigned long *first_frame) +{ + memset(state, 0, sizeof(*state)); + + state->task = task; + state->sp = first_frame; + + get_stack_info(first_frame, state->task, &state->stack_info, + &state->stack_mask); + + if (!__kernel_text_address(*first_frame)) + unwind_next_frame(state); +} +EXPORT_SYMBOL_GPL(__unwind_start); |