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Diffstat (limited to 'arch/arm64/kernel/perf_callchain.c')
-rw-r--r--arch/arm64/kernel/perf_callchain.c118
1 files changed, 4 insertions, 114 deletions
diff --git a/arch/arm64/kernel/perf_callchain.c b/arch/arm64/kernel/perf_callchain.c
index 6d157f3218..e8ed5673f4 100644
--- a/arch/arm64/kernel/perf_callchain.c
+++ b/arch/arm64/kernel/perf_callchain.c
@@ -10,94 +10,12 @@
#include <asm/pointer_auth.h>
-struct frame_tail {
- struct frame_tail __user *fp;
- unsigned long lr;
-} __attribute__((packed));
-
-/*
- * Get the return address for a single stackframe and return a pointer to the
- * next frame tail.
- */
-static struct frame_tail __user *
-user_backtrace(struct frame_tail __user *tail,
- struct perf_callchain_entry_ctx *entry)
-{
- struct frame_tail buftail;
- unsigned long err;
- unsigned long lr;
-
- /* Also check accessibility of one struct frame_tail beyond */
- if (!access_ok(tail, sizeof(buftail)))
- return NULL;
-
- pagefault_disable();
- err = __copy_from_user_inatomic(&buftail, tail, sizeof(buftail));
- pagefault_enable();
-
- if (err)
- return NULL;
-
- lr = ptrauth_strip_user_insn_pac(buftail.lr);
-
- perf_callchain_store(entry, lr);
-
- /*
- * Frame pointers should strictly progress back up the stack
- * (towards higher addresses).
- */
- if (tail >= buftail.fp)
- return NULL;
-
- return buftail.fp;
-}
-
-#ifdef CONFIG_COMPAT
-/*
- * The registers we're interested in are at the end of the variable
- * length saved register structure. The fp points at the end of this
- * structure so the address of this struct is:
- * (struct compat_frame_tail *)(xxx->fp)-1
- *
- * This code has been adapted from the ARM OProfile support.
- */
-struct compat_frame_tail {
- compat_uptr_t fp; /* a (struct compat_frame_tail *) in compat mode */
- u32 sp;
- u32 lr;
-} __attribute__((packed));
-
-static struct compat_frame_tail __user *
-compat_user_backtrace(struct compat_frame_tail __user *tail,
- struct perf_callchain_entry_ctx *entry)
+static bool callchain_trace(void *data, unsigned long pc)
{
- struct compat_frame_tail buftail;
- unsigned long err;
-
- /* Also check accessibility of one struct frame_tail beyond */
- if (!access_ok(tail, sizeof(buftail)))
- return NULL;
-
- pagefault_disable();
- err = __copy_from_user_inatomic(&buftail, tail, sizeof(buftail));
- pagefault_enable();
-
- if (err)
- return NULL;
-
- perf_callchain_store(entry, buftail.lr);
-
- /*
- * Frame pointers should strictly progress back up the stack
- * (towards higher addresses).
- */
- if (tail + 1 >= (struct compat_frame_tail __user *)
- compat_ptr(buftail.fp))
- return NULL;
+ struct perf_callchain_entry_ctx *entry = data;
- return (struct compat_frame_tail __user *)compat_ptr(buftail.fp) - 1;
+ return perf_callchain_store(entry, pc) == 0;
}
-#endif /* CONFIG_COMPAT */
void perf_callchain_user(struct perf_callchain_entry_ctx *entry,
struct pt_regs *regs)
@@ -107,35 +25,7 @@ void perf_callchain_user(struct perf_callchain_entry_ctx *entry,
return;
}
- perf_callchain_store(entry, regs->pc);
-
- if (!compat_user_mode(regs)) {
- /* AARCH64 mode */
- struct frame_tail __user *tail;
-
- tail = (struct frame_tail __user *)regs->regs[29];
-
- while (entry->nr < entry->max_stack &&
- tail && !((unsigned long)tail & 0x7))
- tail = user_backtrace(tail, entry);
- } else {
-#ifdef CONFIG_COMPAT
- /* AARCH32 compat mode */
- struct compat_frame_tail __user *tail;
-
- tail = (struct compat_frame_tail __user *)regs->compat_fp - 1;
-
- while ((entry->nr < entry->max_stack) &&
- tail && !((unsigned long)tail & 0x3))
- tail = compat_user_backtrace(tail, entry);
-#endif
- }
-}
-
-static bool callchain_trace(void *data, unsigned long pc)
-{
- struct perf_callchain_entry_ctx *entry = data;
- return perf_callchain_store(entry, pc) == 0;
+ arch_stack_walk_user(callchain_trace, entry, regs);
}
void perf_callchain_kernel(struct perf_callchain_entry_ctx *entry,