aboutsummaryrefslogtreecommitdiffstats
path: root/arch/s390/kernel/perf_regs.c
diff options
context:
space:
mode:
authorHeiko Carstens <heiko.carstens@de.ibm.com>2015-06-06 12:44:25 +0200
committerMartin Schwidefsky <schwidefsky@de.ibm.com>2017-11-16 15:06:11 +0100
commitc33eff600584ed493adfb42e3f130a6335f97750 (patch)
treee717a41af2f054a88ebd3617d1ae8da2dc8c03c0 /arch/s390/kernel/perf_regs.c
parent9232c3c741200167e44ae9d0e434092657ab4534 (diff)
s390/perf: add perf_regs support and user stack dump
Add s390 support to dump user stack to user space for DWARF stack unwinding. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Reviewed-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com> Reviewed-and-tested-by: Thomas Richter <tmricht@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Diffstat (limited to 'arch/s390/kernel/perf_regs.c')
-rw-r--r--arch/s390/kernel/perf_regs.c49
1 files changed, 49 insertions, 0 deletions
diff --git a/arch/s390/kernel/perf_regs.c b/arch/s390/kernel/perf_regs.c
new file mode 100644
index 000000000000..e883e6a2146a
--- /dev/null
+++ b/arch/s390/kernel/perf_regs.c
@@ -0,0 +1,49 @@
+#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>
+
+u64 perf_reg_value(struct pt_regs *regs, int idx)
+{
+ if (WARN_ON_ONCE((u32)idx >= PERF_REG_S390_MAX))
+ return 0;
+
+ if (idx == PERF_REG_S390_MASK)
+ return regs->psw.mask;
+ if (idx == PERF_REG_S390_PC)
+ return regs->psw.addr;
+
+ return regs->gprs[idx];
+}
+
+#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,
+ struct pt_regs *regs_user_copy)
+{
+ /*
+ * Use the regs from the first interruption and let
+ * perf_sample_regs_intr() handle interrupts (regs == get_irq_regs()).
+ */
+ regs_user->regs = task_pt_regs(current);
+ regs_user->abi = perf_reg_abi(current);
+}

Privacy Policy