arch/s390/kernel/perf_regs.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 #include <linux/perf_event.h>
   3 #include <linux/perf_regs.h>
   4 #include <linux/kernel.h>
   5 #include <linux/errno.h>
   6 #include <linux/bug.h>
   7 #include <asm/ptrace.h>
   8 #include <asm/fpu/api.h>
   9 #include <asm/fpu/types.h>
  10
  11 u64 perf_reg_value(struct pt_regs *regs, int idx)
  12 {
  13         freg_t fp;
  14
  15         if (WARN_ON_ONCE((u32)idx >= PERF_REG_S390_MAX))
  16                 return 0;
  17
  18         if (idx >= PERF_REG_S390_R0 && idx <= PERF_REG_S390_R15)
  19                 return regs->gprs[idx];
  20
  21         if (idx >= PERF_REG_S390_FP0 && idx <= PERF_REG_S390_FP15) {
  22                 if (!user_mode(regs))
  23                         return 0;
  24
  25                 idx -= PERF_REG_S390_FP0;
  26                 fp = MACHINE_HAS_VX ? *(freg_t *)(current->thread.fpu.vxrs + idx)
  27                                     : current->thread.fpu.fprs[idx];
  28                 return fp.ui;
  29         }
  30
  31         if (idx == PERF_REG_S390_MASK)
  32                 return regs->psw.mask;
  33         if (idx == PERF_REG_S390_PC)
  34                 return regs->psw.addr;
  35
  36         return regs->gprs[idx];
  37 }
  38
  39 #define REG_RESERVED (~((1UL << PERF_REG_S390_MAX) - 1))
  40
  41 int perf_reg_validate(u64 mask)
  42 {
  43         if (!mask || mask & REG_RESERVED)
  44                 return -EINVAL;
  45
  46         return 0;
  47 }
  48
  49 u64 perf_reg_abi(struct task_struct *task)
  50 {
  51         if (test_tsk_thread_flag(task, TIF_31BIT))
  52                 return PERF_SAMPLE_REGS_ABI_32;
  53
  54         return PERF_SAMPLE_REGS_ABI_64;
  55 }
  56
  57 void perf_get_regs_user(struct perf_regs *regs_user,
  58                         struct pt_regs *regs,
  59                         struct pt_regs *regs_user_copy)
  60 {
  61         /*
  62          * Use the regs from the first interruption and let
  63          * perf_sample_regs_intr() handle interrupts (regs == get_irq_regs()).
  64          *
  65          * Also save FPU registers for user-space tasks only.
  66          */
  67         regs_user->regs = task_pt_regs(current);
  68         if (user_mode(regs_user->regs))
  69                 save_fpu_regs();
  70         regs_user->abi = perf_reg_abi(current);
  71 }