Menu
▾
▴
[PATCH 9/9] metag: OProfile support
|
From: James H. <jam...@im...> - 2013-03-15 14:00:41
|
Add OProfile support for metag, using the perf backend, and falling back
to generic timer based sampling if perf counter interrupt support is
disabled.
The oprofile code prepends "metag/" to the perf pmu name to give
"metag/meta2" which is more consistent with other oprofile arch names.
The backtrace code makes use of <asm/stacktrace.h> for kernel
backtracing, and a simple frame pointer walk for userland backtracing.
Signed-off-by: James Hogan <jam...@im...>
Cc: Robert Richter <rr...@ke...>
Cc: opr...@li...
---
arch/metag/Kconfig | 4 +++
arch/metag/Makefile | 2 ++
arch/metag/oprofile/Makefile | 17 +++++++++++
arch/metag/oprofile/backtrace.c | 63 +++++++++++++++++++++++++++++++++++++++
arch/metag/oprofile/backtrace.h | 6 ++++
arch/metag/oprofile/common.c | 66 +++++++++++++++++++++++++++++++++++++++++
6 files changed, 158 insertions(+)
create mode 100644 arch/metag/oprofile/Makefile
create mode 100644 arch/metag/oprofile/backtrace.c
create mode 100644 arch/metag/oprofile/backtrace.h
create mode 100644 arch/metag/oprofile/common.c
diff --git a/arch/metag/Kconfig b/arch/metag/Kconfig
index afc8973..b06b418 100644
--- a/arch/metag/Kconfig
+++ b/arch/metag/Kconfig
@@ -25,6 +25,7 @@ config METAG
select HAVE_MEMBLOCK
select HAVE_MEMBLOCK_NODE_MAP
select HAVE_MOD_ARCH_SPECIFIC
+ select HAVE_OPROFILE
select HAVE_PERF_EVENTS
select HAVE_SYSCALL_TRACEPOINTS
select IRQ_DOMAIN
@@ -209,6 +210,9 @@ config METAG_PERFCOUNTER_IRQS
When disabled, Performance Counters information will be collected
based on Timer Interrupt.
+config HW_PERF_EVENTS
+ def_bool METAG_PERFCOUNTER_IRQS && PERF_EVENTS
+
config METAG_DA
bool "DA support"
help
diff --git a/arch/metag/Makefile b/arch/metag/Makefile
index 81bd6a1..b566116 100644
--- a/arch/metag/Makefile
+++ b/arch/metag/Makefile
@@ -49,6 +49,8 @@ core-y += arch/metag/mm/
libs-y += arch/metag/lib/
libs-y += arch/metag/tbx/
+drivers-$(CONFIG_OPROFILE) += arch/metag/oprofile/
+
boot := arch/metag/boot
boot_targets += uImage
diff --git a/arch/metag/oprofile/Makefile b/arch/metag/oprofile/Makefile
new file mode 100644
index 0000000..c9639d4
--- /dev/null
+++ b/arch/metag/oprofile/Makefile
@@ -0,0 +1,17 @@
+obj-$(CONFIG_OPROFILE) += oprofile.o
+
+oprofile-core-y += buffer_sync.o
+oprofile-core-y += cpu_buffer.o
+oprofile-core-y += event_buffer.o
+oprofile-core-y += oprof.o
+oprofile-core-y += oprofile_files.o
+oprofile-core-y += oprofile_stats.o
+oprofile-core-y += oprofilefs.o
+oprofile-core-y += timer_int.o
+oprofile-core-$(CONFIG_HW_PERF_EVENTS) += oprofile_perf.o
+
+oprofile-y += backtrace.o
+oprofile-y += common.o
+oprofile-y += $(addprefix ../../../drivers/oprofile/,$(oprofile-core-y))
+
+ccflags-y += -Werror
diff --git a/arch/metag/oprofile/backtrace.c b/arch/metag/oprofile/backtrace.c
new file mode 100644
index 0000000..7cc3f37
--- /dev/null
+++ b/arch/metag/oprofile/backtrace.c
@@ -0,0 +1,63 @@
+/*
+ * Copyright (C) 2010-2013 Imagination Technologies Ltd.
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+#include <linux/oprofile.h>
+#include <linux/uaccess.h>
+#include <asm/processor.h>
+#include <asm/stacktrace.h>
+
+#include "backtrace.h"
+
+static void user_backtrace_fp(unsigned long __user *fp, unsigned int depth)
+{
+ while (depth-- && access_ok(VERIFY_READ, fp, 8)) {
+ unsigned long addr;
+ unsigned long __user *fpnew;
+ if (__copy_from_user_inatomic(&addr, fp + 1, sizeof(addr)))
+ break;
+ addr -= 4;
+
+ oprofile_add_trace(addr);
+
+ /* stack grows up, so frame pointers must decrease */
+ if (__copy_from_user_inatomic(&fpnew, fp + 0, sizeof(fpnew)))
+ break;
+ if (fpnew >= fp)
+ break;
+ fp = fpnew;
+ }
+}
+
+static int kernel_backtrace_frame(struct stackframe *frame, void *data)
+{
+ unsigned int *depth = data;
+
+ oprofile_add_trace(frame->pc);
+
+ /* decrement depth and stop if we reach 0 */
+ if ((*depth)-- == 0)
+ return 1;
+
+ /* otherwise onto the next frame */
+ return 0;
+}
+
+void metag_backtrace(struct pt_regs * const regs, unsigned int depth)
+{
+ if (user_mode(regs)) {
+ unsigned long *fp = (unsigned long *)regs->ctx.AX[1].U0;
+ user_backtrace_fp((unsigned long __user __force *)fp, depth);
+ } else {
+ struct stackframe frame;
+ frame.fp = regs->ctx.AX[1].U0; /* A0FrP */
+ frame.sp = user_stack_pointer(regs); /* A0StP */
+ frame.lr = 0; /* from stack */
+ frame.pc = regs->ctx.CurrPC; /* PC */
+ walk_stackframe(&frame, &kernel_backtrace_frame, &depth);
+ }
+}
diff --git a/arch/metag/oprofile/backtrace.h b/arch/metag/oprofile/backtrace.h
new file mode 100644
index 0000000..c0fcc42
--- /dev/null
+++ b/arch/metag/oprofile/backtrace.h
@@ -0,0 +1,6 @@
+#ifndef _METAG_OPROFILE_BACKTRACE_H
+#define _METAG_OPROFILE_BACKTRACE_H
+
+void metag_backtrace(struct pt_regs * const regs, unsigned int depth);
+
+#endif
diff --git a/arch/metag/oprofile/common.c b/arch/metag/oprofile/common.c
new file mode 100644
index 0000000..ba26152
--- /dev/null
+++ b/arch/metag/oprofile/common.c
@@ -0,0 +1,66 @@
+/*
+ * arch/metag/oprofile/common.c
+ *
+ * Copyright (C) 2013 Imagination Technologies Ltd.
+ *
+ * Based on arch/sh/oprofile/common.c:
+ *
+ * Copyright (C) 2003 - 2010 Paul Mundt
+ *
+ * Based on arch/mips/oprofile/common.c:
+ *
+ * Copyright (C) 2004, 2005 Ralf Baechle
+ * Copyright (C) 2005 MIPS Technologies, Inc.
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/oprofile.h>
+#include <linux/perf_event.h>
+#include <linux/slab.h>
+
+#include "backtrace.h"
+
+#ifdef CONFIG_HW_PERF_EVENTS
+/*
+ * This will need to be reworked when multiple PMUs are supported.
+ */
+static char *metag_pmu_op_name;
+
+char *op_name_from_perf_id(void)
+{
+ return metag_pmu_op_name;
+}
+
+int __init oprofile_arch_init(struct oprofile_operations *ops)
+{
+ ops->backtrace = metag_backtrace;
+
+ if (perf_num_counters() == 0)
+ return -ENODEV;
+
+ metag_pmu_op_name = kasprintf(GFP_KERNEL, "metag/%s",
+ perf_pmu_name());
+ if (unlikely(!metag_pmu_op_name))
+ return -ENOMEM;
+
+ return oprofile_perf_init(ops);
+}
+
+void oprofile_arch_exit(void)
+{
+ oprofile_perf_exit();
+ kfree(metag_pmu_op_name);
+}
+#else
+int __init oprofile_arch_init(struct oprofile_operations *ops)
+{
+ ops->backtrace = metag_backtrace;
+ /* fall back to timer interrupt PC sampling */
+ return -ENODEV;
+}
+void oprofile_arch_exit(void) {}
+#endif /* CONFIG_HW_PERF_EVENTS */
--
1.8.1.2
|