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authorAnton Arapov <anton@redhat.com>2012-04-16 10:05:28 +0200
committerAnton Arapov <anton@redhat.com>2012-04-16 10:05:28 +0200
commitb4b6116a13633898cf868f2f103c96a90c4c20f8 (patch)
tree93d1b7e2cfcdf473d8d4ff3ad141fa864f8491f6 /arch/arm/oprofile/common.c
parentedd4be777c953e5faafc80d091d3084b4343f5d3 (diff)
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fedora kernel: d9aad82f3319f3cfd1aebc01234254ef0c37ad84v3.3.2-1
Signed-off-by: Anton Arapov <anton@redhat.com>
Diffstat (limited to 'arch/arm/oprofile/common.c')
-rw-r--r--arch/arm/oprofile/common.c122
1 files changed, 122 insertions, 0 deletions
diff --git a/arch/arm/oprofile/common.c b/arch/arm/oprofile/common.c
new file mode 100644
index 00000000000..4e0a371630b
--- /dev/null
+++ b/arch/arm/oprofile/common.c
@@ -0,0 +1,122 @@
+/**
+ * @file common.c
+ *
+ * @remark Copyright 2004 Oprofile Authors
+ * @remark Copyright 2010 ARM Ltd.
+ * @remark Read the file COPYING
+ *
+ * @author Zwane Mwaikambo
+ * @author Will Deacon [move to perf]
+ */
+
+#include <linux/cpumask.h>
+#include <linux/init.h>
+#include <linux/mutex.h>
+#include <linux/oprofile.h>
+#include <linux/perf_event.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <asm/stacktrace.h>
+#include <linux/uaccess.h>
+
+#include <asm/perf_event.h>
+#include <asm/ptrace.h>
+
+#ifdef CONFIG_HW_PERF_EVENTS
+char *op_name_from_perf_id(void)
+{
+ enum arm_perf_pmu_ids id = armpmu_get_pmu_id();
+
+ switch (id) {
+ case ARM_PERF_PMU_ID_XSCALE1:
+ return "arm/xscale1";
+ case ARM_PERF_PMU_ID_XSCALE2:
+ return "arm/xscale2";
+ case ARM_PERF_PMU_ID_V6:
+ return "arm/armv6";
+ case ARM_PERF_PMU_ID_V6MP:
+ return "arm/mpcore";
+ case ARM_PERF_PMU_ID_CA8:
+ return "arm/armv7";
+ case ARM_PERF_PMU_ID_CA9:
+ return "arm/armv7-ca9";
+ default:
+ return NULL;
+ }
+}
+#endif
+
+static int report_trace(struct stackframe *frame, void *d)
+{
+ unsigned int *depth = d;
+
+ if (*depth) {
+ oprofile_add_trace(frame->pc);
+ (*depth)--;
+ }
+
+ return *depth == 0;
+}
+
+/*
+ * The registers we're interested in are at the end of the variable
+ * length saved register structure. The fp points at the end of this
+ * structure so the address of this struct is:
+ * (struct frame_tail *)(xxx->fp)-1
+ */
+struct frame_tail {
+ struct frame_tail *fp;
+ unsigned long sp;
+ unsigned long lr;
+} __attribute__((packed));
+
+static struct frame_tail* user_backtrace(struct frame_tail *tail)
+{
+ struct frame_tail buftail[2];
+
+ /* Also check accessibility of one struct frame_tail beyond */
+ if (!access_ok(VERIFY_READ, tail, sizeof(buftail)))
+ return NULL;
+ if (__copy_from_user_inatomic(buftail, tail, sizeof(buftail)))
+ return NULL;
+
+ oprofile_add_trace(buftail[0].lr);
+
+ /* frame pointers should strictly progress back up the stack
+ * (towards higher addresses) */
+ if (tail + 1 >= buftail[0].fp)
+ return NULL;
+
+ return buftail[0].fp-1;
+}
+
+static void arm_backtrace(struct pt_regs * const regs, unsigned int depth)
+{
+ struct frame_tail *tail = ((struct frame_tail *) regs->ARM_fp) - 1;
+
+ if (!user_mode(regs)) {
+ struct stackframe frame;
+ frame.fp = regs->ARM_fp;
+ frame.sp = regs->ARM_sp;
+ frame.lr = regs->ARM_lr;
+ frame.pc = regs->ARM_pc;
+ walk_stackframe(&frame, report_trace, &depth);
+ return;
+ }
+
+ while (depth-- && tail && !((unsigned long) tail & 3))
+ tail = user_backtrace(tail);
+}
+
+int __init oprofile_arch_init(struct oprofile_operations *ops)
+{
+ /* provide backtrace support also in timer mode: */
+ ops->backtrace = arm_backtrace;
+
+ return oprofile_perf_init(ops);
+}
+
+void oprofile_arch_exit(void)
+{
+ oprofile_perf_exit();
+}