arch/arm64/kernel/perf_regs.c

   1 #include <linux/errno.h>
   2 #include <linux/kernel.h>
   3 #include <linux/perf_event.h>
   4 #include <linux/bug.h>
   5 #include <asm/perf_regs.h>
   6 #include <asm/ptrace.h>
   7
   8 u64 perf_reg_value(struct pt_regs *regs, int idx)
   9 {
  10         if (WARN_ON_ONCE((u32)idx >= PERF_REG_ARM64_MAX))
  11                 return 0;
  12
  13         /*
  14          * Compat (i.e. 32 bit) mode:
  15          * - PC has been set in the pt_regs struct in kernel_entry,
  16          * - Handle SP and LR here.
  17          */
  18         if (compat_user_mode(regs)) {
  19                 if ((u32)idx == PERF_REG_ARM64_SP)
  20                         return regs->compat_sp;
  21                 if ((u32)idx == PERF_REG_ARM64_LR)
  22                         return regs->compat_lr;
  23         }
  24
  25         return regs->regs[idx];
  26 }
  27
  28 #define REG_RESERVED (~((1ULL << PERF_REG_ARM64_MAX) - 1))
  29
  30 int perf_reg_validate(u64 mask)
  31 {
  32         if (!mask || mask & REG_RESERVED)
  33                 return -EINVAL;
  34
  35         return 0;
  36 }
  37
  38 u64 perf_reg_abi(struct task_struct *task)
  39 {
  40         if (is_compat_thread(task_thread_info(task)))
  41                 return PERF_SAMPLE_REGS_ABI_32;
  42         else
  43                 return PERF_SAMPLE_REGS_ABI_64;
  44 }