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-rw-r--r--arch/s390/kernel/perf_regs.c68
1 files changed, 68 insertions, 0 deletions
diff --git a/arch/s390/kernel/perf_regs.c b/arch/s390/kernel/perf_regs.c
new file mode 100644
index 000000000..6e9e5d5e9
--- /dev/null
+++ b/arch/s390/kernel/perf_regs.c
@@ -0,0 +1,68 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/perf_event.h>
+#include <linux/perf_regs.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/bug.h>
+#include <asm/ptrace.h>
+#include <asm/fpu/api.h>
+#include <asm/fpu/types.h>
+
+u64 perf_reg_value(struct pt_regs *regs, int idx)
+{
+ freg_t fp;
+
+ if (idx >= PERF_REG_S390_R0 && idx <= PERF_REG_S390_R15)
+ return regs->gprs[idx];
+
+ if (idx >= PERF_REG_S390_FP0 && idx <= PERF_REG_S390_FP15) {
+ if (!user_mode(regs))
+ return 0;
+
+ idx -= PERF_REG_S390_FP0;
+ fp = MACHINE_HAS_VX ? *(freg_t *)(current->thread.fpu.vxrs + idx)
+ : current->thread.fpu.fprs[idx];
+ return fp.ui;
+ }
+
+ if (idx == PERF_REG_S390_MASK)
+ return regs->psw.mask;
+ if (idx == PERF_REG_S390_PC)
+ return regs->psw.addr;
+
+ WARN_ON_ONCE((u32)idx >= PERF_REG_S390_MAX);
+ return 0;
+}
+
+#define REG_RESERVED (~((1UL << PERF_REG_S390_MAX) - 1))
+
+int perf_reg_validate(u64 mask)
+{
+ if (!mask || mask & REG_RESERVED)
+ return -EINVAL;
+
+ return 0;
+}
+
+u64 perf_reg_abi(struct task_struct *task)
+{
+ if (test_tsk_thread_flag(task, TIF_31BIT))
+ return PERF_SAMPLE_REGS_ABI_32;
+
+ return PERF_SAMPLE_REGS_ABI_64;
+}
+
+void perf_get_regs_user(struct perf_regs *regs_user,
+ struct pt_regs *regs)
+{
+ /*
+ * Use the regs from the first interruption and let
+ * perf_sample_regs_intr() handle interrupts (regs == get_irq_regs()).
+ *
+ * Also save FPU registers for user-space tasks only.
+ */
+ regs_user->regs = task_pt_regs(current);
+ if (user_mode(regs_user->regs))
+ save_fpu_regs();
+ regs_user->abi = perf_reg_abi(current);
+}