ppc64: initial oprofile support

arch/ppc64/Kconfig

@@ -503,6 +503,7 @@ config VIOPATH
 	depends on PPC_ISERIES
 	default y
 
+source "arch/ppc64/oprofile/Kconfig"
 
 menu "Kernel hacking"
 

arch/ppc64/Makefile

@@ -30,6 +30,9 @@ HEAD := arch/ppc64/kernel/head.o
 core-y			+= arch/ppc64/kernel/ arch/ppc64/mm/ arch/ppc64/lib/
 core-$(CONFIG_XMON)	+= arch/ppc64/xmon/
 
+# FIXME: is drivers- right ?
+drivers-$(CONFIG_OPROFILE)		+= arch/ppc64/oprofile/
+
 makeboot = $(call descend,arch/ppc64/boot,$(1))
 
 ifdef CONFIG_PPC_PSERIES

arch/ppc64/kernel/Makefile

@@ -35,6 +35,8 @@ obj-$(CONFIG_RTAS_FLASH) += rtas_flash.o
 
 obj-$(CONFIG_SMP) += smp.o
 
+obj-$(CONFIG_PROFILING)	+= profile.o
+
 obj-y += prom.o lmb.o rtas.o rtas-proc.o chrp_setup.o i8259.o
 
 include $(TOPDIR)/Rules.make

arch/ppc64/kernel/misc.S

@@ -743,7 +743,7 @@ _GLOBAL(sys_call_table32)
 	.llong .sys_ni_syscall		/* reserved for alloc_hugepages */
 	.llong .sys_ni_syscall		/* reserved for free_hugepages */
 	.llong .sys_exit_group
-	.llong .sys_lookup_dcookie	/* 245 */
+	.llong .sys32_lookup_dcookie	/* 245 */
 	.llong .sys_epoll_create
 	.llong .sys_epoll_ctl
 	.llong .sys_epoll_wait

arch/ppc64/kernel/ppc_ksyms.c

@@ -245,3 +245,6 @@ EXPORT_SYMBOL(debugger_fault_handler);
 #endif
 
 EXPORT_SYMBOL(tb_ticks_per_usec);
+
+EXPORT_SYMBOL_GPL(register_profile_notifier);
+EXPORT_SYMBOL_GPL(unregister_profile_notifier);

arch/ppc64/kernel/profile.c

+/*
+ *	linux/arch/i386/kernel/profile.c
+ *
+ *	(C) 2002 John Levon <levon@movementarian.org>
+ *
+ */
+
+#include <linux/profile.h>
+#include <linux/spinlock.h>
+#include <linux/notifier.h>
+#include <linux/irq.h>
+#include <asm/hw_irq.h> 
+ 
+static struct notifier_block * profile_listeners;
+static rwlock_t profile_lock = RW_LOCK_UNLOCKED;
+ 
+int register_profile_notifier(struct notifier_block * nb)
+{
+	int err;
+	write_lock_irq(&profile_lock);
+	err = notifier_chain_register(&profile_listeners, nb);
+	write_unlock_irq(&profile_lock);
+	return err;
+}
+
+
+int unregister_profile_notifier(struct notifier_block * nb)
+{
+	int err;
+	write_lock_irq(&profile_lock);
+	err = notifier_chain_unregister(&profile_listeners, nb);
+	write_unlock_irq(&profile_lock);
+	return err;
+}
+
+
+void ppc64_profile_hook(struct pt_regs * regs)
+{
+	read_lock(&profile_lock);
+	notifier_call_chain(&profile_listeners, 0, regs);
+	read_unlock(&profile_lock);
+}

arch/ppc64/kernel/sys_ppc32.c

@@ -4522,3 +4522,12 @@ unsigned long sys32_mmap2(unsigned long addr, size_t len,
 	/* This should remain 12 even if PAGE_SIZE changes */
 	return sys_mmap(addr, len, prot, flags, fd, pgoff << 12);
 }
+
+extern int sys_lookup_dcookie(u64 cookie64, char *buf, size_t len);
+
+long sys32_lookup_dcookie(u32 cookie_high, u32 cookie_low, char *buf,
+			  size_t len)
+{
+	return sys_lookup_dcookie((u64)cookie_high << 32 | cookie_low,
+				  buf, len);
+}

arch/ppc64/kernel/time.c

@@ -46,6 +46,7 @@
 #include <linux/mc146818rtc.h>
 #include <linux/time.h>
 #include <linux/init.h>
+#include <linux/profile.h>
 
 #include <asm/segment.h>
 #include <asm/io.h>
@@ -95,21 +96,35 @@ extern unsigned long wall_jiffies;
 extern unsigned long lpEvent_count;
 extern int smp_tb_synchronized;
 
-extern unsigned long prof_cpu_mask;
-extern unsigned int * prof_buffer;
-extern unsigned long prof_len;
-extern unsigned long prof_shift;
-extern char _stext;
-
 void ppc_adjtimex(void);
 
 static unsigned adjusting_time = 0;
 
-static inline void ppc_do_profile (unsigned long nip)
+/*
+ * The profiling function is SMP safe. (nothing can mess
+ * around with "current", and the profiling counters are
+ * updated with atomic operations). This is especially
+ * useful with a profiling multiplier != 1
+ */
+static inline void ppc64_do_profile(struct pt_regs *regs)
 {
+	unsigned long nip;
+	extern unsigned long prof_cpu_mask;
+	extern char _stext;
+#ifdef CONFIG_PROFILING
+	extern void ppc64_profile_hook(struct pt_regs *);
+
+	ppc64_profile_hook(regs);
+#endif
+
+	if (user_mode(regs))
+		return;
+
 	if (!prof_buffer)
 		return;
 
+	nip = instruction_pointer(regs);
+
 	/*
 	 * Only measure the CPUs specified by /proc/irq/prof_cpu_mask.
 	 * (default is all CPUs.)
@@ -129,7 +144,6 @@ static inline void ppc_do_profile (unsigned long nip)
 	atomic_inc((atomic_t *)&prof_buffer[nip]);
 }
 
-
 static __inline__ void timer_check_rtc(void)
 {
         /*
@@ -259,8 +273,7 @@ int timer_interrupt(struct pt_regs * regs)
 	irq_enter();
 
 #ifndef CONFIG_PPC_ISERIES
-	if (!user_mode(regs))
-		ppc_do_profile(instruction_pointer(regs));
+	ppc64_do_profile(regs);
 #endif
 
 	lpaca->xLpPaca.xIntDword.xFields.xDecrInt = 0;

arch/ppc64/oprofile/Kconfig

+
+menu "Profiling support"
+	depends on EXPERIMENTAL
+
+config PROFILING
+	bool "Profiling support (EXPERIMENTAL)"
+	help
+	  Say Y here to enable the extended profiling support mechanisms used
+	  by profilers such as OProfile.
+	  
+
+config OPROFILE
+	tristate "OProfile system profiling (EXPERIMENTAL)"
+	depends on PROFILING
+	help
+	  OProfile is a profiling system capable of profiling the
+	  whole system, include the kernel, kernel modules, libraries,
+	  and applications.
+
+	  If unsure, say N.
+
+endmenu
+

arch/ppc64/oprofile/Makefile

+obj-$(CONFIG_OPROFILE) += oprofile.o
+
+DRIVER_OBJS = $(addprefix ../../../drivers/oprofile/, \
+		oprof.o cpu_buffer.o buffer_sync.o \
+		event_buffer.o oprofile_files.o \
+		oprofilefs.o oprofile_stats.o )
+
+oprofile-y				:= $(DRIVER_OBJS) init.o timer_int.o

arch/ppc64/oprofile/init.c

+/**
+ * @file init.c
+ *
+ * @remark Copyright 2002 OProfile authors
+ * @remark Read the file COPYING
+ *
+ * @author John Levon <levon@movementarian.org>
+ */
+
+#include <linux/kernel.h>
+#include <linux/oprofile.h>
+#include <linux/init.h>
+ 
+extern void timer_init(struct oprofile_operations ** ops, enum oprofile_cpu * cpu);
+
+int __init oprofile_arch_init(struct oprofile_operations ** ops, enum oprofile_cpu * cpu)
+{
+	timer_init(ops, cpu);
+	return 0;
+}

arch/ppc64/oprofile/timer_int.c

+/**
+ * @file timer_int.c
+ *
+ * @remark Copyright 2002 OProfile authors
+ * @remark Read the file COPYING
+ *
+ * @author John Levon <levon@movementarian.org>
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/notifier.h>
+#include <linux/smp.h>
+#include <linux/irq.h>
+#include <linux/oprofile.h>
+#include <asm/ptrace.h>
+ 
+static int timer_notify(struct notifier_block * self, unsigned long val, void * data)
+{
+	struct pt_regs * regs = (struct pt_regs *)data;
+	int cpu = smp_processor_id();
+ 
+	oprofile_add_sample(instruction_pointer(regs), 0, cpu);
+	return 0;
+}
+ 
+ 
+static struct notifier_block timer_notifier = {
+	.notifier_call	= timer_notify,
+};
+ 
+
+static int timer_start(void)
+{
+	return register_profile_notifier(&timer_notifier);
+}
+
+
+static void timer_stop(void)
+{
+	unregister_profile_notifier(&timer_notifier);
+}
+
+
+static struct oprofile_operations timer_ops = {
+	.start	= timer_start,
+	.stop	= timer_stop
+};
+
+ 
+void __init timer_init(struct oprofile_operations ** ops, enum oprofile_cpu * cpu)
+{
+	*ops = &timer_ops;
+	*cpu = OPROFILE_CPU_TIMER;
+	printk(KERN_INFO "oprofile: using timer interrupt.\n");
+}

include/asm-ppc64/hw_irq.h

@@ -80,5 +80,26 @@ static inline void __do_save_and_cli(unsigned long *flags)
 struct hw_interrupt_type;
 static inline void hw_resend_irq(struct hw_interrupt_type *h, unsigned int i) {}
  
+struct notifier_block;
+ 
+#ifdef CONFIG_PROFILING
+ 
+int register_profile_notifier(struct notifier_block * nb);
+int unregister_profile_notifier(struct notifier_block * nb);
+
+#else
+
+static inline int register_profile_notifier(struct notifier_block * nb)
+{
+	return -ENOSYS;
+}
+
+static inline int unregister_profile_notifier(struct notifier_block * nb)
+{
+	return -ENOSYS;
+}
+
+#endif /* CONFIG_PROFILING */
+ 
 #endif /* _PPC64_HW_IRQ_H */
 #endif /* __KERNEL__ */