From: John Levon <levon@movementarian.org>
This patch provides support for IA64 hardware performance counters via the
perfmon interface.
Signed-off-by: Andrew Morton <akpm@osdl.org>
---
25-akpm/arch/ia64/oprofile/Kconfig | 4 +
25-akpm/arch/ia64/oprofile/Makefile | 1
25-akpm/arch/ia64/oprofile/init.c | 9 ++-
25-akpm/arch/ia64/oprofile/perfmon.c | 105 +++++++++++++++++++++++++++++++++++
4 files changed, 118 insertions(+), 1 deletion(-)
diff -puN arch/ia64/oprofile/init.c~oprofile-ia64-performance-counter-support arch/ia64/oprofile/init.c
--- 25/arch/ia64/oprofile/init.c~oprofile-ia64-performance-counter-support 2004-08-21 14:12:17.150973528 -0700
+++ 25-akpm/arch/ia64/oprofile/init.c 2004-08-21 14:12:17.158972312 -0700
@@ -12,14 +12,21 @@
#include <linux/init.h>
#include <linux/errno.h>
-extern void timer_init(struct oprofile_operations ** ops);
+extern int perfmon_init(struct oprofile_operations ** ops);
+extern void perfmon_exit(void);
int __init oprofile_arch_init(struct oprofile_operations ** ops)
{
+#ifdef CONFIG_PERFMON
+ return perfmon_init(ops);
+#endif
return -ENODEV;
}
void oprofile_arch_exit(void)
{
+#ifdef CONFIG_PERFMON
+ perfmon_exit();
+#endif
}
diff -puN arch/ia64/oprofile/Kconfig~oprofile-ia64-performance-counter-support arch/ia64/oprofile/Kconfig
--- 25/arch/ia64/oprofile/Kconfig~oprofile-ia64-performance-counter-support 2004-08-21 14:12:17.151973376 -0700
+++ 25-akpm/arch/ia64/oprofile/Kconfig 2004-08-21 14:12:17.158972312 -0700
@@ -16,6 +16,10 @@ config OPROFILE
whole system, include the kernel, kernel modules, libraries,
and applications.
+ Due to firmware bugs, you may need to use the "nohalt" boot
+ option if you're using OProfile with the hardware performance
+ counters.
+
If unsure, say N.
endmenu
diff -puN arch/ia64/oprofile/Makefile~oprofile-ia64-performance-counter-support arch/ia64/oprofile/Makefile
--- 25/arch/ia64/oprofile/Makefile~oprofile-ia64-performance-counter-support 2004-08-21 14:12:17.153973072 -0700
+++ 25-akpm/arch/ia64/oprofile/Makefile 2004-08-21 14:12:17.158972312 -0700
@@ -7,3 +7,4 @@ DRIVER_OBJS := $(addprefix ../../../driv
timer_int.o )
oprofile-y := $(DRIVER_OBJS) init.o
+oprofile-$(CONFIG_PERFMON) += perfmon.o
diff -puN /dev/null arch/ia64/oprofile/perfmon.c
--- /dev/null 2003-09-15 06:40:47.000000000 -0700
+++ 25-akpm/arch/ia64/oprofile/perfmon.c 2004-08-21 14:12:17.159972160 -0700
@@ -0,0 +1,105 @@
+/**
+ * @file perfmon.c
+ *
+ * @remark Copyright 2003 OProfile authors
+ * @remark Read the file COPYING
+ *
+ * @author John Levon <levon@movementarian.org>
+ */
+
+#include <linux/kernel.h>
+#include <linux/config.h>
+#include <linux/oprofile.h>
+#include <linux/sched.h>
+#include <asm/perfmon.h>
+#include <asm/ptrace.h>
+#include <asm/errno.h>
+
+static int allow_ints;
+
+static int
+perfmon_handler(struct task_struct *task, void *buf, pfm_ovfl_arg_t *arg,
+ struct pt_regs *regs, unsigned long stamp)
+{
+ int cpu = smp_processor_id();
+ unsigned long eip = instruction_pointer(regs);
+ int event = arg->pmd_eventid;
+
+ arg->ovfl_ctrl.bits.reset_ovfl_pmds = 1;
+
+ /* the owner of the oprofile event buffer may have exited
+ * without perfmon being shutdown (e.g. SIGSEGV)
+ */
+ if (allow_ints)
+ oprofile_add_sample(eip, !user_mode(regs), event, cpu);
+ return 0;
+}
+
+
+static int perfmon_start(void)
+{
+ allow_ints = 1;
+ return 0;
+}
+
+
+static void perfmon_stop(void)
+{
+ allow_ints = 0;
+}
+
+
+#define OPROFILE_FMT_UUID { \
+ 0x77, 0x7a, 0x6e, 0x61, 0x20, 0x65, 0x73, 0x69, 0x74, 0x6e, 0x72, 0x20, 0x61, 0x65, 0x0a, 0x6c }
+
+static pfm_buffer_fmt_t oprofile_fmt = {
+ .fmt_name = "oprofile_format",
+ .fmt_uuid = OPROFILE_FMT_UUID,
+ .fmt_handler = perfmon_handler,
+};
+
+
+static char * get_cpu_type(void)
+{
+ __u8 family = local_cpu_data->family;
+
+ switch (family) {
+ case 0x07:
+ return "ia64/itanium";
+ case 0x1f:
+ return "ia64/itanium2";
+ default:
+ return "ia64/ia64";
+ }
+}
+
+
+/* all the ops are handled via userspace for IA64 perfmon */
+static struct oprofile_operations perfmon_ops = {
+ .start = perfmon_start,
+ .stop = perfmon_stop,
+};
+
+static int using_perfmon;
+
+int perfmon_init(struct oprofile_operations ** ops)
+{
+ int ret = pfm_register_buffer_fmt(&oprofile_fmt);
+ if (ret)
+ return -ENODEV;
+
+ perfmon_ops.cpu_type = get_cpu_type();
+ *ops = &perfmon_ops;
+ using_perfmon = 1;
+ printk(KERN_INFO "oprofile: using perfmon.\n");
+ return 0;
+}
+
+
+void perfmon_exit(void)
+{
+ if (!using_perfmon)
+ return;
+
+ pfm_unregister_buffer_fmt(oprofile_fmt.fmt_uuid);
+}
_