summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorJean Pihet <jean.pihet@linaro.org>2014-02-03 18:18:27 (GMT)
committerChanho Park <chanho61.park@samsung.com>2014-04-16 12:36:49 (GMT)
commitf6c1b855f6bc378672328f353bc36aa2310ad05b (patch)
tree7b753f68fad20f1d71024a843b86116e0aa4261d
parent5321cdf5d023df4a51d55d651384fe526387d2f8 (diff)
downloadlinux-3.10-f6c1b855f6bc378672328f353bc36aa2310ad05b.zip
linux-3.10-f6c1b855f6bc378672328f353bc36aa2310ad05b.tar.gz
linux-3.10-f6c1b855f6bc378672328f353bc36aa2310ad05b.tar.bz2
ARM64: perf: add support for perf registers API
This patch implements the functions required for the perf registers API, allowing the perf tool to interface kernel register dumps with libunwind in order to provide userspace backtracing. Compat mode is also supported. Only the general purpose user space registers are exported, i.e.: PERF_REG_ARM_X0, ... PERF_REG_ARM_X28, PERF_REG_ARM_FP, PERF_REG_ARM_LR, PERF_REG_ARM_SP, PERF_REG_ARM_PC and not the PERF_REG_ARM_V* registers. Signed-off-by: Jean Pihet <jean.pihet@linaro.org> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
-rw-r--r--arch/arm64/Kconfig2
-rw-r--r--arch/arm64/include/asm/ptrace.h1
-rw-r--r--arch/arm64/include/uapi/asm/Kbuild1
-rw-r--r--arch/arm64/include/uapi/asm/perf_regs.h40
-rw-r--r--arch/arm64/kernel/Makefile3
-rw-r--r--arch/arm64/kernel/perf_regs.c44
6 files changed, 90 insertions, 1 deletions
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 79065a5..8761193 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -40,6 +40,8 @@ config ARM64
select HAVE_MEMBLOCK
select HAVE_PATA_PLATFORM
select HAVE_PERF_EVENTS
+ select HAVE_PERF_REGS
+ select HAVE_PERF_USER_STACK_DUMP
select IRQ_DOMAIN
select MODULES_USE_ELF_RELA
select NO_BOOTMEM
diff --git a/arch/arm64/include/asm/ptrace.h b/arch/arm64/include/asm/ptrace.h
index 5233966..35ff2f9 100644
--- a/arch/arm64/include/asm/ptrace.h
+++ b/arch/arm64/include/asm/ptrace.h
@@ -68,6 +68,7 @@
/* Architecturally defined mapping between AArch32 and AArch64 registers */
#define compat_usr(x) regs[(x)]
+#define compat_fp regs[11]
#define compat_sp regs[13]
#define compat_lr regs[14]
#define compat_sp_hyp regs[15]
diff --git a/arch/arm64/include/uapi/asm/Kbuild b/arch/arm64/include/uapi/asm/Kbuild
index e4b78bd..942376d 100644
--- a/arch/arm64/include/uapi/asm/Kbuild
+++ b/arch/arm64/include/uapi/asm/Kbuild
@@ -9,6 +9,7 @@ header-y += byteorder.h
header-y += fcntl.h
header-y += hwcap.h
header-y += kvm_para.h
+header-y += perf_regs.h
header-y += param.h
header-y += ptrace.h
header-y += setup.h
diff --git a/arch/arm64/include/uapi/asm/perf_regs.h b/arch/arm64/include/uapi/asm/perf_regs.h
new file mode 100644
index 0000000..172b831
--- /dev/null
+++ b/arch/arm64/include/uapi/asm/perf_regs.h
@@ -0,0 +1,40 @@
+#ifndef _ASM_ARM64_PERF_REGS_H
+#define _ASM_ARM64_PERF_REGS_H
+
+enum perf_event_arm_regs {
+ PERF_REG_ARM64_X0,
+ PERF_REG_ARM64_X1,
+ PERF_REG_ARM64_X2,
+ PERF_REG_ARM64_X3,
+ PERF_REG_ARM64_X4,
+ PERF_REG_ARM64_X5,
+ PERF_REG_ARM64_X6,
+ PERF_REG_ARM64_X7,
+ PERF_REG_ARM64_X8,
+ PERF_REG_ARM64_X9,
+ PERF_REG_ARM64_X10,
+ PERF_REG_ARM64_X11,
+ PERF_REG_ARM64_X12,
+ PERF_REG_ARM64_X13,
+ PERF_REG_ARM64_X14,
+ PERF_REG_ARM64_X15,
+ PERF_REG_ARM64_X16,
+ PERF_REG_ARM64_X17,
+ PERF_REG_ARM64_X18,
+ PERF_REG_ARM64_X19,
+ PERF_REG_ARM64_X20,
+ PERF_REG_ARM64_X21,
+ PERF_REG_ARM64_X22,
+ PERF_REG_ARM64_X23,
+ PERF_REG_ARM64_X24,
+ PERF_REG_ARM64_X25,
+ PERF_REG_ARM64_X26,
+ PERF_REG_ARM64_X27,
+ PERF_REG_ARM64_X28,
+ PERF_REG_ARM64_X29,
+ PERF_REG_ARM64_LR,
+ PERF_REG_ARM64_SP,
+ PERF_REG_ARM64_PC,
+ PERF_REG_ARM64_MAX,
+};
+#endif /* _ASM_ARM64_PERF_REGS_H */
diff --git a/arch/arm64/kernel/Makefile b/arch/arm64/kernel/Makefile
index cfee827..7d811d9 100644
--- a/arch/arm64/kernel/Makefile
+++ b/arch/arm64/kernel/Makefile
@@ -15,8 +15,9 @@ arm64-obj-$(CONFIG_COMPAT) += sys32.o kuser32.o signal32.o \
sys_compat.o
arm64-obj-$(CONFIG_MODULES) += arm64ksyms.o module.o
arm64-obj-$(CONFIG_SMP) += smp.o smp_spin_table.o topology.o
+arm64-obj-$(CONFIG_PERF_EVENTS) += perf_regs.o
arm64-obj-$(CONFIG_HW_PERF_EVENTS) += perf_event.o
-arm64-obj-$(CONFIG_HAVE_HW_BREAKPOINT)+= hw_breakpoint.o
+arm64-obj-$(CONFIG_HAVE_HW_BREAKPOINT) += hw_breakpoint.o
arm64-obj-$(CONFIG_EARLY_PRINTK) += early_printk.o
arm64-obj-$(CONFIG_ARM64_CPU_SUSPEND) += sleep.o suspend.o
arm64-obj-$(CONFIG_JUMP_LABEL) += jump_label.o
diff --git a/arch/arm64/kernel/perf_regs.c b/arch/arm64/kernel/perf_regs.c
new file mode 100644
index 0000000..f2d6f0a
--- /dev/null
+++ b/arch/arm64/kernel/perf_regs.c
@@ -0,0 +1,44 @@
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/perf_event.h>
+#include <linux/bug.h>
+#include <asm/perf_regs.h>
+#include <asm/ptrace.h>
+
+u64 perf_reg_value(struct pt_regs *regs, int idx)
+{
+ if (WARN_ON_ONCE((u32)idx >= PERF_REG_ARM64_MAX))
+ return 0;
+
+ /*
+ * Compat (i.e. 32 bit) mode:
+ * - PC has been set in the pt_regs struct in kernel_entry,
+ * - Handle SP and LR here.
+ */
+ if (compat_user_mode(regs)) {
+ if ((u32)idx == PERF_REG_ARM64_SP)
+ return regs->compat_sp;
+ if ((u32)idx == PERF_REG_ARM64_LR)
+ return regs->compat_lr;
+ }
+
+ return regs->regs[idx];
+}
+
+#define REG_RESERVED (~((1ULL << PERF_REG_ARM64_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 (is_compat_thread(task_thread_info(task)))
+ return PERF_SAMPLE_REGS_ABI_32;
+ else
+ return PERF_SAMPLE_REGS_ABI_64;
+}