[PATCH V3 2/3] perf/powerpc :add support for sampling intr machine state

Anju T
2015-11-03T06:10:17Z

The perf infrastructure uses a bit mask to find out
valid registers to display. Define a register mask
for supported registers defined in asm/perf_regs.h.
The bit positions also correspond to register IDs
which is used by perf infrastructure to fetch the register
values.CONFIG_HAVE_PERF_REGS enables
sampling of the interrupted machine state.

Signed-off-by: Anju T <anju@linux.vnet.ibm.com>
---
arch/powerpc/Kconfig | 1 +
arch/powerpc/perf/Makefile | 2 +
arch/powerpc/perf/perf_regs.c | 92 +++++++++++++++++++++++++++++++++++++++++++
3 files changed, 95 insertions(+)
create mode 100644 arch/powerpc/perf/perf_regs.c

diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 9a7057e..c4ce60d 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -119,6 +119,7 @@ config PPC
select GENERIC_ATOMIC64 if PPC32
select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
select HAVE_PERF_EVENTS
+ select HAVE_PERF_REGS
select HAVE_REGS_AND_STACK_ACCESS_API
select HAVE_HW_BREAKPOINT if PERF_EVENTS && PPC_BOOK3S_64
select ARCH_WANT_IPC_PARSE_VERSION
diff --git a/arch/powerpc/perf/Makefile b/arch/powerpc/perf/Makefile
index f9c083a..cbae78a 100644
--- a/arch/powerpc/perf/Makefile
+++ b/arch/powerpc/perf/Makefile
@@ -7,6 +7,8 @@ obj64-$(CONFIG_PPC_PERF_CTRS) += power4-pmu.o ppc970-pmu.o power5-pmu.o \
power5+-pmu.o power6-pmu.o power7-pmu.o \
power8-pmu.o
obj32-$(CONFIG_PPC_PERF_CTRS) += mpc7450-pmu.o
+obj-$(CONFIG_PERF_EVENTS) += perf_regs.o
+

obj-$(CONFIG_FSL_EMB_PERF_EVENT) += core-fsl-emb.o
obj-$(CONFIG_FSL_EMB_PERF_EVENT_E500) += e500-pmu.o e6500-pmu.o
diff --git a/arch/powerpc/perf/perf_regs.c b/arch/powerpc/perf/perf_regs.c
new file mode 100644
index 0000000..0520492
--- /dev/null
+++ b/arch/powerpc/perf/perf_regs.c
@@ -0,0 +1,92 @@
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/perf_event.h>
+#include <linux/bug.h>
+#include <linux/stddef.h>
+#include <asm/ptrace.h>
+#include <asm/perf_regs.h>
+
+#define PT_REGS_OFFSET(id, r) [id] = offsetof(struct pt_regs, r)
+
+#define REG_RESERVED (~((1ULL << PERF_REG_POWERPC_MAX) - 1))
+
+static unsigned int pt_regs_offset[PERF_REG_POWERPC_MAX] = {
+ PT_REGS_OFFSET(PERF_REG_POWERPC_GPR0, gpr[0]),
+ PT_REGS_OFFSET(PERF_REG_POWERPC_GPR1, gpr[1]),
+ PT_REGS_OFFSET(PERF_REG_POWERPC_GPR2, gpr[2]),
+ PT_REGS_OFFSET(PERF_REG_POWERPC_GPR3, gpr[3]),
+ PT_REGS_OFFSET(PERF_REG_POWERPC_GPR4, gpr[4]),
+ PT_REGS_OFFSET(PERF_REG_POWERPC_GPR5, gpr[5]),
+ PT_REGS_OFFSET(PERF_REG_POWERPC_GPR6, gpr[6]),
+ PT_REGS_OFFSET(PERF_REG_POWERPC_GPR7, gpr[7]),
+ PT_REGS_OFFSET(PERF_REG_POWERPC_GPR8, gpr[8]),
+ PT_REGS_OFFSET(PERF_REG_POWERPC_GPR9, gpr[9]),
+ PT_REGS_OFFSET(PERF_REG_POWERPC_GPR10, gpr[10]),
+ PT_REGS_OFFSET(PERF_REG_POWERPC_GPR11, gpr[11]),
+ PT_REGS_OFFSET(PERF_REG_POWERPC_GPR12, gpr[12]),
+ PT_REGS_OFFSET(PERF_REG_POWERPC_GPR13, gpr[13]),
+ PT_REGS_OFFSET(PERF_REG_POWERPC_GPR14, gpr[14]),
+ PT_REGS_OFFSET(PERF_REG_POWERPC_GPR15, gpr[15]),
+ PT_REGS_OFFSET(PERF_REG_POWERPC_GPR16, gpr[16]),
+ PT_REGS_OFFSET(PERF_REG_POWERPC_GPR17, gpr[17]),
+ PT_REGS_OFFSET(PERF_REG_POWERPC_GPR18, gpr[18]),
+ PT_REGS_OFFSET(PERF_REG_POWERPC_GPR19, gpr[19]),
+ PT_REGS_OFFSET(PERF_REG_POWERPC_GPR20, gpr[20]),
+ PT_REGS_OFFSET(PERF_REG_POWERPC_GPR21, gpr[21]),
+ PT_REGS_OFFSET(PERF_REG_POWERPC_GPR22, gpr[22]),
+ PT_REGS_OFFSET(PERF_REG_POWERPC_GPR23, gpr[23]),
+ PT_REGS_OFFSET(PERF_REG_POWERPC_GPR24, gpr[24]),
+ PT_REGS_OFFSET(PERF_REG_POWERPC_GPR25, gpr[25]),
+ PT_REGS_OFFSET(PERF_REG_POWERPC_GPR26, gpr[26]),
+ PT_REGS_OFFSET(PERF_REG_POWERPC_GPR27, gpr[27]),
+ PT_REGS_OFFSET(PERF_REG_POWERPC_GPR28, gpr[28]),
+ PT_REGS_OFFSET(PERF_REG_POWERPC_GPR29, gpr[29]),
+ PT_REGS_OFFSET(PERF_REG_POWERPC_GPR30, gpr[30]),
+ PT_REGS_OFFSET(PERF_REG_POWERPC_GPR31, gpr[31]),
+ PT_REGS_OFFSET(PERF_REG_POWERPC_NIP, nip),
+ PT_REGS_OFFSET(PERF_REG_POWERPC_MSR, msr),
+ PT_REGS_OFFSET(PERF_REG_POWERPC_ORIG_R3, orig_gpr3),
+ PT_REGS_OFFSET(PERF_REG_POWERPC_CTR, ctr),
+ PT_REGS_OFFSET(PERF_REG_POWERPC_LNK, link),
+ PT_REGS_OFFSET(PERF_REG_POWERPC_XER, xer),
+ PT_REGS_OFFSET(PERF_REG_POWERPC_CCR, ccr),
+#ifdef __powerpc64__
+ PT_REGS_OFFSET(PERF_REG_POWERPC_SOFTE, softe),
+#else
+ PT_REGS_OFFSET(PERF_REG_POWERPC_MQ, mq),
+#endif
+ PT_REGS_OFFSET(PERF_REG_POWERPC_TRAP, trap),
+ PT_REGS_OFFSET(PERF_REG_POWERPC_DAR, dar),
+ PT_REGS_OFFSET(PERF_REG_POWERPC_DSISR, dsisr),
+};
+
+u64 perf_reg_value(struct pt_regs *regs, int idx)
+{
+ if (WARN_ON_ONCE(idx >= PERF_REG_POWERPC_MAX))
+ return 0;
+ return regs_get_register(regs, pt_regs_offset[idx]);
+}
+
+int perf_reg_validate(u64 mask)
+{
+ if (!mask || mask & REG_RESERVED)
+ return -EINVAL;
+ return 0;
+}
+
+u64 perf_reg_abi(struct task_struct *task)
+{
+ 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)
+{
+ /*
+ *TODO : Update this function when
+ *PERF_SAMPLE_REGS_USER is enabled
+ */
+ return;
+}
--
2.1.0