drivers: Remove CONFIG_OPROFILE support

The "oprofile" user-space tools don't use the kernel OPROFILE support
any more, and haven't in a long time. User-space has been converted to
the perf interfaces.

Remove kernel's old oprofile support.
Suggested-by: Christoph Hellwig <hch@infradead.org>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Robert Richter <rric@kernel.org>
Acked-by: Paul E. McKenney <paulmck@kernel.org> #RCU
Acked-by: William Cohen <wcohen@redhat.com>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Thomas Gleixner <tglx@linutronix.de>

Documentation/RCU/NMI-RCU.rst

@@ -8,8 +8,7 @@ Although RCU is usually used to protect read-mostly data structures,
 it is possible to use RCU to provide dynamic non-maskable interrupt
 handlers, as well as dynamic irq handlers.  This document describes
 how to do this, drawing loosely from Zwane Mwaikambo's NMI-timer
-work in "arch/x86/oprofile/nmi_timer_int.c" and in
-"arch/x86/kernel/traps.c".
+work in "arch/x86/kernel/traps.c".
 
 The relevant pieces of code are listed below, each followed by a
 brief explanation::

Documentation/admin-guide/kernel-parameters.txt

@@ -3458,20 +3458,6 @@
 			For example, to override I2C bus2:
 			omap_mux=i2c2_scl.i2c2_scl=0x100,i2c2_sda.i2c2_sda=0x100
 
-	oprofile.timer=	[HW]
-			Use timer interrupt instead of performance counters
-
-	oprofile.cpu_type=	Force an oprofile cpu type
-			This might be useful if you have an older oprofile
-			userland or if you want common events.
-			Format: { arch_perfmon }
-			arch_perfmon: [X86] Force use of architectural
-				perfmon on Intel CPUs instead of the
-				CPU specific event set.
-			timer: [X86] Force use of architectural NMI
-				timer mode (see also oprofile.timer
-				for generic hr timer mode)
-
 	oops=panic	Always panic on oopses. Default is to just kill the
 			process, but there is a small probability of
 			deadlocking the machine.

Documentation/process/magic-number.rst

@@ -135,7 +135,6 @@ FW_HEADER_MAGIC       0x65726F66       fw_header                ``drivers/atm/fo
 SLOT_MAGIC            0x67267321       slot                     ``drivers/hotplug/cpqphp.h``
 SLOT_MAGIC            0x67267322       slot                     ``drivers/hotplug/acpiphp.h``
 LO_MAGIC              0x68797548       nbd_device               ``include/linux/nbd.h``
-OPROFILE_MAGIC        0x6f70726f       super_block              ``drivers/oprofile/oprofilefs.h``
 M3_STATE_MAGIC        0x734d724d       m3_state                 ``sound/oss/maestro3.c``
 VMALLOC_MAGIC         0x87654320       snd_alloc_track          ``sound/core/memory.c``
 KMALLOC_MAGIC         0x87654321       snd_alloc_track          ``sound/core/memory.c``

Documentation/translations/it_IT/process/magic-number.rst

@@ -141,7 +141,6 @@ FW_HEADER_MAGIC       0x65726F66       fw_header                ``drivers/atm/fo
 SLOT_MAGIC            0x67267321       slot                     ``drivers/hotplug/cpqphp.h``
 SLOT_MAGIC            0x67267322       slot                     ``drivers/hotplug/acpiphp.h``
 LO_MAGIC              0x68797548       nbd_device               ``include/linux/nbd.h``
-OPROFILE_MAGIC        0x6f70726f       super_block              ``drivers/oprofile/oprofilefs.h``
 M3_STATE_MAGIC        0x734d724d       m3_state                 ``sound/oss/maestro3.c``
 VMALLOC_MAGIC         0x87654320       snd_alloc_track          ``sound/core/memory.c``
 KMALLOC_MAGIC         0x87654321       snd_alloc_track          ``sound/core/memory.c``

Documentation/translations/zh_CN/process/magic-number.rst

@@ -124,7 +124,6 @@ FW_HEADER_MAGIC       0x65726F66       fw_header                ``drivers/atm/fo
 SLOT_MAGIC            0x67267321       slot                     ``drivers/hotplug/cpqphp.h``
 SLOT_MAGIC            0x67267322       slot                     ``drivers/hotplug/acpiphp.h``
 LO_MAGIC              0x68797548       nbd_device               ``include/linux/nbd.h``
-OPROFILE_MAGIC        0x6f70726f       super_block              ``drivers/oprofile/oprofilefs.h``
 M3_STATE_MAGIC        0x734d724d       m3_state                 ``sound/oss/maestro3.c``
 VMALLOC_MAGIC         0x87654320       snd_alloc_track          ``sound/core/memory.c``
 KMALLOC_MAGIC         0x87654321       snd_alloc_track          ``sound/core/memory.c``

MAINTAINERS

@@ -1414,7 +1414,6 @@ F:	arch/arm*/include/asm/hw_breakpoint.h
 F:	arch/arm*/include/asm/perf_event.h
 F:	arch/arm*/kernel/hw_breakpoint.c
 F:	arch/arm*/kernel/perf_*
-F:	arch/arm/oprofile/common.c
 F:	drivers/perf/
 F:	include/linux/perf/arm_pmu.h
 
@@ -4083,7 +4082,6 @@ W:	http://www.ibm.com/developerworks/power/cell/
 F:	arch/powerpc/include/asm/cell*.h
 F:	arch/powerpc/include/asm/spu*.h
 F:	arch/powerpc/include/uapi/asm/spu*.h
-F:	arch/powerpc/oprofile/*cell*
 F:	arch/powerpc/platforms/cell/
 
 CELLWISE CW2015 BATTERY DRIVER
@@ -13311,15 +13309,6 @@ S:	Maintained
 T:	git git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound.git
 F:	sound/drivers/opl4/
 
-OPROFILE
-M:	Robert Richter <rric@kernel.org>
-L:	oprofile-list@lists.sf.net
-S:	Maintained
-F:	arch/*/include/asm/oprofile*.h
-F:	arch/*/oprofile/
-F:	drivers/oprofile/
-F:	include/linux/oprofile.h
-
 ORACLE CLUSTER FILESYSTEM 2 (OCFS2)
 M:	Mark Fasheh <mark@fasheh.com>
 M:	Joel Becker <jlbec@evilplan.org>

arch/Kconfig

@@ -33,38 +33,6 @@ config HOTPLUG_SMT
 config GENERIC_ENTRY
        bool
 
-config OPROFILE
-	tristate "OProfile system profiling"
-	depends on PROFILING
-	depends on HAVE_OPROFILE
-	select RING_BUFFER
-	select RING_BUFFER_ALLOW_SWAP
-	help
-	  OProfile is a profiling system capable of profiling the
-	  whole system, include the kernel, kernel modules, libraries,
-	  and applications.
-
-	  If unsure, say N.
-
-config OPROFILE_EVENT_MULTIPLEX
-	bool "OProfile multiplexing support (EXPERIMENTAL)"
-	default n
-	depends on OPROFILE && X86
-	help
-	  The number of hardware counters is limited. The multiplexing
-	  feature enables OProfile to gather more events than counters
-	  are provided by the hardware. This is realized by switching
-	  between events at a user specified time interval.
-
-	  If unsure, say N.
-
-config HAVE_OPROFILE
-	bool
-
-config OPROFILE_NMI_TIMER
-	def_bool y
-	depends on PERF_EVENTS && HAVE_PERF_EVENTS_NMI && !PPC64
-
 config KPROBES
 	bool "Kprobes"
 	depends on MODULES

drivers/oprofile/buffer_sync.h

-/**
- * @file buffer_sync.h
- *
- * @remark Copyright 2002 OProfile authors
- * @remark Read the file COPYING
- *
- * @author John Levon <levon@movementarian.org>
- */
-
-#ifndef OPROFILE_BUFFER_SYNC_H
-#define OPROFILE_BUFFER_SYNC_H
-
-/* add the necessary profiling hooks */
-int sync_start(void);
-
-/* remove the hooks */
-void sync_stop(void);
-
-/* sync the given CPU's buffer */
-void sync_buffer(int cpu);
-
-#endif /* OPROFILE_BUFFER_SYNC_H */

drivers/oprofile/cpu_buffer.h

-/**
- * @file cpu_buffer.h
- *
- * @remark Copyright 2002-2009 OProfile authors
- * @remark Read the file COPYING
- *
- * @author John Levon <levon@movementarian.org>
- * @author Robert Richter <robert.richter@amd.com>
- */
-
-#ifndef OPROFILE_CPU_BUFFER_H
-#define OPROFILE_CPU_BUFFER_H
-
-#include <linux/types.h>
-#include <linux/spinlock.h>
-#include <linux/workqueue.h>
-#include <linux/cache.h>
-#include <linux/sched.h>
-#include <linux/ring_buffer.h>
-
-struct task_struct;
-
-int alloc_cpu_buffers(void);
-void free_cpu_buffers(void);
-
-void start_cpu_work(void);
-void end_cpu_work(void);
-void flush_cpu_work(void);
-
-/* CPU buffer is composed of such entries (which are
- * also used for context switch notes)
- */
-struct op_sample {
-	unsigned long eip;
-	unsigned long event;
-	unsigned long data[];
-};
-
-struct op_entry;
-
-struct oprofile_cpu_buffer {
-	unsigned long buffer_size;
-	struct task_struct *last_task;
-	int last_is_kernel;
-	int tracing;
-	unsigned long sample_received;
-	unsigned long sample_lost_overflow;
-	unsigned long backtrace_aborted;
-	unsigned long sample_invalid_eip;
-	int cpu;
-	struct delayed_work work;
-};
-
-DECLARE_PER_CPU(struct oprofile_cpu_buffer, op_cpu_buffer);
-
-/*
- * Resets the cpu buffer to a sane state.
- *
- * reset these to invalid values; the next sample collected will
- * populate the buffer with proper values to initialize the buffer
- */
-static inline void op_cpu_buffer_reset(int cpu)
-{
-	struct oprofile_cpu_buffer *cpu_buf = &per_cpu(op_cpu_buffer, cpu);
-
-	cpu_buf->last_is_kernel = -1;
-	cpu_buf->last_task = NULL;
-}
-
-/*
- * op_cpu_buffer_add_data() and op_cpu_buffer_write_commit() may be
- * called only if op_cpu_buffer_write_reserve() did not return NULL or
- * entry->event != NULL, otherwise entry->size or entry->event will be
- * used uninitialized.
- */
-
-struct op_sample
-*op_cpu_buffer_write_reserve(struct op_entry *entry, unsigned long size);
-int op_cpu_buffer_write_commit(struct op_entry *entry);
-struct op_sample *op_cpu_buffer_read_entry(struct op_entry *entry, int cpu);
-unsigned long op_cpu_buffer_entries(int cpu);
-
-/* returns the remaining free size of data in the entry */
-static inline
-int op_cpu_buffer_add_data(struct op_entry *entry, unsigned long val)
-{
-	if (!entry->size)
-		return 0;
-	*entry->data = val;
-	entry->size--;
-	entry->data++;
-	return entry->size;
-}
-
-/* returns the size of data in the entry */
-static inline
-int op_cpu_buffer_get_size(struct op_entry *entry)
-{
-	return entry->size;
-}
-
-/* returns 0 if empty or the size of data including the current value */
-static inline
-int op_cpu_buffer_get_data(struct op_entry *entry, unsigned long *val)
-{
-	int size = entry->size;
-	if (!size)
-		return 0;
-	*val = *entry->data;
-	entry->size--;
-	entry->data++;
-	return size;
-}
-
-/* extra data flags */
-#define KERNEL_CTX_SWITCH	(1UL << 0)
-#define IS_KERNEL		(1UL << 1)
-#define TRACE_BEGIN		(1UL << 2)
-#define USER_CTX_SWITCH		(1UL << 3)
-
-#endif /* OPROFILE_CPU_BUFFER_H */

drivers/oprofile/event_buffer.c

-/**
- * @file event_buffer.c
- *
- * @remark Copyright 2002 OProfile authors
- * @remark Read the file COPYING
- *
- * @author John Levon <levon@movementarian.org>
- *
- * This is the global event buffer that the user-space
- * daemon reads from. The event buffer is an untyped array
- * of unsigned longs. Entries are prefixed by the
- * escape value ESCAPE_CODE followed by an identifying code.
- */
-
-#include <linux/vmalloc.h>
-#include <linux/oprofile.h>
-#include <linux/sched/signal.h>
-#include <linux/capability.h>
-#include <linux/dcookies.h>
-#include <linux/fs.h>
-#include <linux/uaccess.h>
-
-#include "oprof.h"
-#include "event_buffer.h"
-#include "oprofile_stats.h"
-
-DEFINE_MUTEX(buffer_mutex);
-
-static unsigned long buffer_opened;
-static DECLARE_WAIT_QUEUE_HEAD(buffer_wait);
-static unsigned long *event_buffer;
-static unsigned long buffer_size;
-static unsigned long buffer_watershed;
-static size_t buffer_pos;
-/* atomic_t because wait_event checks it outside of buffer_mutex */
-static atomic_t buffer_ready = ATOMIC_INIT(0);
-
-/*
- * Add an entry to the event buffer. When we get near to the end we
- * wake up the process sleeping on the read() of the file. To protect
- * the event_buffer this function may only be called when buffer_mutex
- * is set.
- */
-void add_event_entry(unsigned long value)
-{
-	/*
-	 * This shouldn't happen since all workqueues or handlers are
-	 * canceled or flushed before the event buffer is freed.
-	 */
-	if (!event_buffer) {
-		WARN_ON_ONCE(1);
-		return;
-	}
-
-	if (buffer_pos == buffer_size) {
-		atomic_inc(&oprofile_stats.event_lost_overflow);
-		return;
-	}
-
-	event_buffer[buffer_pos] = value;
-	if (++buffer_pos == buffer_size - buffer_watershed) {
-		atomic_set(&buffer_ready, 1);
-		wake_up(&buffer_wait);
-	}
-}
-
-
-/* Wake up the waiting process if any. This happens
- * on "echo 0 >/dev/oprofile/enable" so the daemon
- * processes the data remaining in the event buffer.
- */
-void wake_up_buffer_waiter(void)
-{
-	mutex_lock(&buffer_mutex);
-	atomic_set(&buffer_ready, 1);
-	wake_up(&buffer_wait);
-	mutex_unlock(&buffer_mutex);
-}
-
-
-int alloc_event_buffer(void)
-{
-	unsigned long flags;
-
-	raw_spin_lock_irqsave(&oprofilefs_lock, flags);
-	buffer_size = oprofile_buffer_size;
-	buffer_watershed = oprofile_buffer_watershed;
-	raw_spin_unlock_irqrestore(&oprofilefs_lock, flags);
-
-	if (buffer_watershed >= buffer_size)
-		return -EINVAL;
-
-	buffer_pos = 0;
-	event_buffer = vmalloc(array_size(buffer_size, sizeof(unsigned long)));
-	if (!event_buffer)
-		return -ENOMEM;
-
-	return 0;
-}
-
-
-void free_event_buffer(void)
-{
-	mutex_lock(&buffer_mutex);
-	vfree(event_buffer);
-	buffer_pos = 0;
-	event_buffer = NULL;
-	mutex_unlock(&buffer_mutex);
-}
-
-
-static int event_buffer_open(struct inode *inode, struct file *file)
-{
-	int err = -EPERM;
-
-	if (!perfmon_capable())
-		return -EPERM;
-
-	if (test_and_set_bit_lock(0, &buffer_opened))
-		return -EBUSY;
-
-	/* Register as a user of dcookies
-	 * to ensure they persist for the lifetime of
-	 * the open event file
-	 */
-	err = -EINVAL;
-	file->private_data = dcookie_register();
-	if (!file->private_data)
-		goto out;
-
-	if ((err = oprofile_setup()))
-		goto fail;
-
-	/* NB: the actual start happens from userspace
-	 * echo 1 >/dev/oprofile/enable
-	 */
-
-	return nonseekable_open(inode, file);
-
-fail:
-	dcookie_unregister(file->private_data);
-out:
-	__clear_bit_unlock(0, &buffer_opened);
-	return err;
-}
-
-
-static int event_buffer_release(struct inode *inode, struct file *file)
-{
-	oprofile_stop();
-	oprofile_shutdown();
-	dcookie_unregister(file->private_data);
-	buffer_pos = 0;
-	atomic_set(&buffer_ready, 0);
-	__clear_bit_unlock(0, &buffer_opened);
-	return 0;
-}
-
-
-static ssize_t event_buffer_read(struct file *file, char __user *buf,
-				 size_t count, loff_t *offset)
-{
-	int retval = -EINVAL;
-	size_t const max = buffer_size * sizeof(unsigned long);
-
-	/* handling partial reads is more trouble than it's worth */
-	if (count != max || *offset)
-		return -EINVAL;
-
-	wait_event_interruptible(buffer_wait, atomic_read(&buffer_ready));
-
-	if (signal_pending(current))
-		return -EINTR;
-
-	/* can't currently happen */
-	if (!atomic_read(&buffer_ready))
-		return -EAGAIN;
-
-	mutex_lock(&buffer_mutex);
-
-	/* May happen if the buffer is freed during pending reads. */
-	if (!event_buffer) {
-		retval = -EINTR;
-		goto out;
-	}
-
-	atomic_set(&buffer_ready, 0);
-
-	retval = -EFAULT;
-
-	count = buffer_pos * sizeof(unsigned long);
-
-	if (copy_to_user(buf, event_buffer, count))
-		goto out;
-
-	retval = count;
-	buffer_pos = 0;
-
-out:
-	mutex_unlock(&buffer_mutex);
-	return retval;
-}
-
-const struct file_operations event_buffer_fops = {
-	.open		= event_buffer_open,
-	.release	= event_buffer_release,
-	.read		= event_buffer_read,
-	.llseek		= no_llseek,
-};

drivers/oprofile/event_buffer.h

-/**
- * @file event_buffer.h
- *
- * @remark Copyright 2002 OProfile authors
- * @remark Read the file COPYING
- *
- * @author John Levon <levon@movementarian.org>
- */
-
-#ifndef EVENT_BUFFER_H
-#define EVENT_BUFFER_H
-
-#include <linux/types.h>
-#include <linux/mutex.h>
-
-int alloc_event_buffer(void);
-
-void free_event_buffer(void);
-
-/**
- * Add data to the event buffer.
- * The data passed is free-form, but typically consists of
- * file offsets, dcookies, context information, and ESCAPE codes.
- */
-void add_event_entry(unsigned long data);
-
-/* wake up the process sleeping on the event file */
-void wake_up_buffer_waiter(void);
-
-#define INVALID_COOKIE ~0UL
-#define NO_COOKIE 0UL
-
-extern const struct file_operations event_buffer_fops;
-
-/* mutex between sync_cpu_buffers() and the
- * file reading code.
- */
-extern struct mutex buffer_mutex;
-
-#endif /* EVENT_BUFFER_H */

drivers/oprofile/nmi_timer_int.c

-// SPDX-License-Identifier: GPL-2.0
-/**
- * @file nmi_timer_int.c
- *
- * @remark Copyright 2011 Advanced Micro Devices, Inc.
- *
- * @author Robert Richter <robert.richter@amd.com>
- */
-
-#include <linux/init.h>
-#include <linux/smp.h>
-#include <linux/errno.h>
-#include <linux/oprofile.h>
-#include <linux/perf_event.h>
-
-#ifdef CONFIG_OPROFILE_NMI_TIMER
-
-static DEFINE_PER_CPU(struct perf_event *, nmi_timer_events);
-static int ctr_running;
-
-static struct perf_event_attr nmi_timer_attr = {
-	.type           = PERF_TYPE_HARDWARE,
-	.config         = PERF_COUNT_HW_CPU_CYCLES,
-	.size           = sizeof(struct perf_event_attr),
-	.pinned         = 1,
-	.disabled       = 1,
-};
-
-static void nmi_timer_callback(struct perf_event *event,
-			       struct perf_sample_data *data,
-			       struct pt_regs *regs)
-{
-	event->hw.interrupts = 0;       /* don't throttle interrupts */
-	oprofile_add_sample(regs, 0);
-}
-
-static int nmi_timer_start_cpu(int cpu)
-{
-	struct perf_event *event = per_cpu(nmi_timer_events, cpu);
-
-	if (!event) {
-		event = perf_event_create_kernel_counter(&nmi_timer_attr, cpu, NULL,
-							 nmi_timer_callback, NULL);
-		if (IS_ERR(event))
-			return PTR_ERR(event);
-		per_cpu(nmi_timer_events, cpu) = event;
-	}
-
-	if (event && ctr_running)
-		perf_event_enable(event);
-
-	return 0;
-}
-
-static void nmi_timer_stop_cpu(int cpu)
-{
-	struct perf_event *event = per_cpu(nmi_timer_events, cpu);
-
-	if (event && ctr_running)
-		perf_event_disable(event);
-}
-
-static int nmi_timer_cpu_online(unsigned int cpu)
-{
-	nmi_timer_start_cpu(cpu);
-	return 0;
-}
-static int nmi_timer_cpu_predown(unsigned int cpu)
-{
-	nmi_timer_stop_cpu(cpu);
-	return 0;
-}
-
-static int nmi_timer_start(void)
-{
-	int cpu;
-
-	get_online_cpus();
-	ctr_running = 1;
-	for_each_online_cpu(cpu)
-		nmi_timer_start_cpu(cpu);
-	put_online_cpus();
-
-	return 0;
-}
-
-static void nmi_timer_stop(void)
-{
-	int cpu;
-
-	get_online_cpus();
-	for_each_online_cpu(cpu)
-		nmi_timer_stop_cpu(cpu);
-	ctr_running = 0;
-	put_online_cpus();
-}
-
-static enum cpuhp_state hp_online;
-
-static void nmi_timer_shutdown(void)
-{
-	struct perf_event *event;
-	int cpu;
-
-	cpuhp_remove_state(hp_online);
-	for_each_possible_cpu(cpu) {
-		event = per_cpu(nmi_timer_events, cpu);
-		if (!event)
-			continue;
-		perf_event_disable(event);
-		per_cpu(nmi_timer_events, cpu) = NULL;
-		perf_event_release_kernel(event);
-	}
-}
-
-static int nmi_timer_setup(void)
-{
-	int err;
-	u64 period;
-
-	/* clock cycles per tick: */
-	period = (u64)cpu_khz * 1000;
-	do_div(period, HZ);
-	nmi_timer_attr.sample_period = period;
-
-	err = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "oprofile/nmi:online",
-				nmi_timer_cpu_online, nmi_timer_cpu_predown);
-	if (err < 0) {
-		nmi_timer_shutdown();
-		return err;
-	}
-	hp_online = err;
-	return 0;
-}
-
-int __init op_nmi_timer_init(struct oprofile_operations *ops)
-{
-	int err = 0;
-
-	err = nmi_timer_setup();
-	if (err)
-		return err;
-	nmi_timer_shutdown();		/* only check, don't alloc */
-
-	ops->create_files	= NULL;
-	ops->setup		= nmi_timer_setup;
-	ops->shutdown		= nmi_timer_shutdown;
-	ops->start		= nmi_timer_start;
-	ops->stop		= nmi_timer_stop;
-	ops->cpu_type		= "timer";
-
-	printk(KERN_INFO "oprofile: using NMI timer interrupt.\n");
-
-	return 0;
-}
-
-#endif

drivers/oprofile/oprof.c

-/**
- * @file oprof.c
- *
- * @remark Copyright 2002 OProfile authors
- * @remark Read the file COPYING
- *
- * @author John Levon <levon@movementarian.org>
- */
-
-#include <linux/kernel.h>
-#include <linux/module.h>
-#include <linux/init.h>
-#include <linux/oprofile.h>
-#include <linux/moduleparam.h>
-#include <linux/workqueue.h>
-#include <linux/time.h>
-#include <linux/mutex.h>
-
-#include "oprof.h"
-#include "event_buffer.h"
-#include "cpu_buffer.h"
-#include "buffer_sync.h"
-#include "oprofile_stats.h"
-
-struct oprofile_operations oprofile_ops;
-
-unsigned long oprofile_started;
-unsigned long oprofile_backtrace_depth;
-static unsigned long is_setup;
-static DEFINE_MUTEX(start_mutex);
-
-/* timer
-   0 - use performance monitoring hardware if available
-   1 - use the timer int mechanism regardless
- */
-static int timer = 0;
-
-int oprofile_setup(void)
-{
-	int err;
-
-	mutex_lock(&start_mutex);
-
-	if ((err = alloc_cpu_buffers()))
-		goto out;
-
-	if ((err = alloc_event_buffer()))
-		goto out1;
-
-	if (oprofile_ops.setup && (err = oprofile_ops.setup()))
-		goto out2;
-
-	/* Note even though this starts part of the
-	 * profiling overhead, it's necessary to prevent
-	 * us missing task deaths and eventually oopsing
-	 * when trying to process the event buffer.
-	 */
-	if (oprofile_ops.sync_start) {
-		int sync_ret = oprofile_ops.sync_start();
-		switch (sync_ret) {
-		case 0:
-			goto post_sync;
-		case 1:
-			goto do_generic;
-		case -1:
-			goto out3;
-		default:
-			goto out3;
-		}
-	}
-do_generic:
-	if ((err = sync_start()))
-		goto out3;
-
-post_sync:
-	is_setup = 1;
-	mutex_unlock(&start_mutex);
-	return 0;
-
-out3:
-	if (oprofile_ops.shutdown)
-		oprofile_ops.shutdown();
-out2:
-	free_event_buffer();
-out1:
-	free_cpu_buffers();
-out:
-	mutex_unlock(&start_mutex);
-	return err;
-}
-
-#ifdef CONFIG_OPROFILE_EVENT_MULTIPLEX
-
-static void switch_worker(struct work_struct *work);
-static DECLARE_DELAYED_WORK(switch_work, switch_worker);
-
-static void start_switch_worker(void)
-{
-	if (oprofile_ops.switch_events)
-		schedule_delayed_work(&switch_work, oprofile_time_slice);
-}
-
-static void stop_switch_worker(void)
-{
-	cancel_delayed_work_sync(&switch_work);
-}
-
-static void switch_worker(struct work_struct *work)
-{
-	if (oprofile_ops.switch_events())
-		return;
-
-	atomic_inc(&oprofile_stats.multiplex_counter);
-	start_switch_worker();
-}
-
-/* User inputs in ms, converts to jiffies */
-int oprofile_set_timeout(unsigned long val_msec)
-{
-	int err = 0;
-	unsigned long time_slice;
-
-	mutex_lock(&start_mutex);
-
-	if (oprofile_started) {
-		err = -EBUSY;
-		goto out;
-	}
-
-	if (!oprofile_ops.switch_events) {
-		err = -EINVAL;
-		goto out;
-	}
-
-	time_slice = msecs_to_jiffies(val_msec);
-	if (time_slice == MAX_JIFFY_OFFSET) {
-		err = -EINVAL;
-		goto out;
-	}
-
-	oprofile_time_slice = time_slice;
-
-out:
-	mutex_unlock(&start_mutex);
-	return err;
-
-}
-
-#else
-
-static inline void start_switch_worker(void) { }
-static inline void stop_switch_worker(void) { }
-
-#endif
-
-/* Actually start profiling (echo 1>/dev/oprofile/enable) */
-int oprofile_start(void)
-{
-	int err = -EINVAL;
-
-	mutex_lock(&start_mutex);
-
-	if (!is_setup)
-		goto out;
-
-	err = 0;
-
-	if (oprofile_started)
-		goto out;
-
-	oprofile_reset_stats();
-
-	if ((err = oprofile_ops.start()))
-		goto out;
-
-	start_switch_worker();
-
-	oprofile_started = 1;
-out:
-	mutex_unlock(&start_mutex);
-	return err;
-}
-
-
-/* echo 0>/dev/oprofile/enable */
-void oprofile_stop(void)
-{
-	mutex_lock(&start_mutex);
-	if (!oprofile_started)
-		goto out;
-	oprofile_ops.stop();
-	oprofile_started = 0;
-
-	stop_switch_worker();
-
-	/* wake up the daemon to read what remains */
-	wake_up_buffer_waiter();
-out:
-	mutex_unlock(&start_mutex);
-}
-
-
-void oprofile_shutdown(void)
-{
-	mutex_lock(&start_mutex);
-	if (oprofile_ops.sync_stop) {
-		int sync_ret = oprofile_ops.sync_stop();
-		switch (sync_ret) {
-		case 0:
-			goto post_sync;
-		case 1:
-			goto do_generic;
-		default:
-			goto post_sync;
-		}
-	}
-do_generic:
-	sync_stop();
-post_sync:
-	if (oprofile_ops.shutdown)
-		oprofile_ops.shutdown();
-	is_setup = 0;
-	free_event_buffer();
-	free_cpu_buffers();
-	mutex_unlock(&start_mutex);
-}
-
-int oprofile_set_ulong(unsigned long *addr, unsigned long val)
-{
-	int err = -EBUSY;
-
-	mutex_lock(&start_mutex);
-	if (!oprofile_started) {
-		*addr = val;
-		err = 0;
-	}
-	mutex_unlock(&start_mutex);
-
-	return err;
-}
-
-static int timer_mode;
-
-static int __init oprofile_init(void)
-{
-	int err;
-
-	/* always init architecture to setup backtrace support */
-	timer_mode = 0;
-	err = oprofile_arch_init(&oprofile_ops);
-	if (!err) {
-		if (!timer && !oprofilefs_register())
-			return 0;
-		oprofile_arch_exit();
-	}
-
-	/* setup timer mode: */
-	timer_mode = 1;
-	/* no nmi timer mode if oprofile.timer is set */
-	if (timer || op_nmi_timer_init(&oprofile_ops)) {
-		err = oprofile_timer_init(&oprofile_ops);
-		if (err)
-			return err;
-	}
-
-	return oprofilefs_register();
-}
-
-
-static void __exit oprofile_exit(void)
-{
-	oprofilefs_unregister();
-	if (!timer_mode)
-		oprofile_arch_exit();
-}
-
-
-module_init(oprofile_init);
-module_exit(oprofile_exit);
-
-module_param_named(timer, timer, int, 0644);
-MODULE_PARM_DESC(timer, "force use of timer interrupt");
-
-MODULE_LICENSE("GPL");
-MODULE_AUTHOR("John Levon <levon@movementarian.org>");
-MODULE_DESCRIPTION("OProfile system profiler");

drivers/oprofile/oprof.h

-/**
- * @file oprof.h
- *
- * @remark Copyright 2002 OProfile authors
- * @remark Read the file COPYING
- *
- * @author John Levon <levon@movementarian.org>
- */
-
-#ifndef OPROF_H
-#define OPROF_H
-
-int oprofile_setup(void);
-void oprofile_shutdown(void);
-
-int oprofilefs_register(void);
-void oprofilefs_unregister(void);
-
-int oprofile_start(void);
-void oprofile_stop(void);
-
-struct oprofile_operations;
-
-extern unsigned long oprofile_buffer_size;
-extern unsigned long oprofile_cpu_buffer_size;
-extern unsigned long oprofile_buffer_watershed;
-extern unsigned long oprofile_time_slice;
-
-extern struct oprofile_operations oprofile_ops;
-extern unsigned long oprofile_started;
-extern unsigned long oprofile_backtrace_depth;
-
-struct dentry;
-
-void oprofile_create_files(struct dentry *root);
-int oprofile_timer_init(struct oprofile_operations *ops);
-#ifdef CONFIG_OPROFILE_NMI_TIMER
-int op_nmi_timer_init(struct oprofile_operations *ops);
-#else
-static inline int op_nmi_timer_init(struct oprofile_operations *ops)
-{
-	return -ENODEV;
-}
-#endif
-
-
-int oprofile_set_ulong(unsigned long *addr, unsigned long val);
-int oprofile_set_timeout(unsigned long time);
-
-#endif /* OPROF_H */

drivers/oprofile/oprofile_files.c

-/**
- * @file oprofile_files.c
- *
- * @remark Copyright 2002 OProfile authors
- * @remark Read the file COPYING
- *
- * @author John Levon <levon@movementarian.org>
- */
-
-#include <linux/fs.h>
-#include <linux/oprofile.h>
-#include <linux/jiffies.h>
-
-#include "event_buffer.h"
-#include "oprofile_stats.h"
-#include "oprof.h"
-
-#define BUFFER_SIZE_DEFAULT		131072
-#define CPU_BUFFER_SIZE_DEFAULT		8192
-#define BUFFER_WATERSHED_DEFAULT	32768	/* FIXME: tune */
-#define TIME_SLICE_DEFAULT		1
-
-unsigned long oprofile_buffer_size;
-unsigned long oprofile_cpu_buffer_size;
-unsigned long oprofile_buffer_watershed;
-unsigned long oprofile_time_slice;
-
-#ifdef CONFIG_OPROFILE_EVENT_MULTIPLEX
-
-static ssize_t timeout_read(struct file *file, char __user *buf,
-		size_t count, loff_t *offset)
-{
-	return oprofilefs_ulong_to_user(jiffies_to_msecs(oprofile_time_slice),
-					buf, count, offset);
-}
-
-
-static ssize_t timeout_write(struct file *file, char const __user *buf,
-		size_t count, loff_t *offset)
-{
-	unsigned long val;
-	int retval;
-
-	if (*offset)
-		return -EINVAL;
-
-	retval = oprofilefs_ulong_from_user(&val, buf, count);
-	if (retval <= 0)
-		return retval;
-
-	retval = oprofile_set_timeout(val);
-
-	if (retval)
-		return retval;
-	return count;
-}
-
-
-static const struct file_operations timeout_fops = {
-	.read		= timeout_read,
-	.write		= timeout_write,
-	.llseek		= default_llseek,
-};
-
-#endif
-
-
-static ssize_t depth_read(struct file *file, char __user *buf, size_t count, loff_t *offset)
-{
-	return oprofilefs_ulong_to_user(oprofile_backtrace_depth, buf, count,
-					offset);
-}
-
-
-static ssize_t depth_write(struct file *file, char const __user *buf, size_t count, loff_t *offset)
-{
-	unsigned long val;
-	int retval;
-
-	if (*offset)
-		return -EINVAL;
-
-	if (!oprofile_ops.backtrace)
-		return -EINVAL;
-
-	retval = oprofilefs_ulong_from_user(&val, buf, count);
-	if (retval <= 0)
-		return retval;
-
-	retval = oprofile_set_ulong(&oprofile_backtrace_depth, val);
-	if (retval)
-		return retval;
-
-	return count;
-}
-
-
-static const struct file_operations depth_fops = {
-	.read		= depth_read,
-	.write		= depth_write,
-	.llseek		= default_llseek,
-};
-
-
-static ssize_t pointer_size_read(struct file *file, char __user *buf, size_t count, loff_t *offset)
-{
-	return oprofilefs_ulong_to_user(sizeof(void *), buf, count, offset);
-}
-
-
-static const struct file_operations pointer_size_fops = {
-	.read		= pointer_size_read,
-	.llseek		= default_llseek,
-};
-
-
-static ssize_t cpu_type_read(struct file *file, char __user *buf, size_t count, loff_t *offset)
-{
-	return oprofilefs_str_to_user(oprofile_ops.cpu_type, buf, count, offset);
-}
-
-
-static const struct file_operations cpu_type_fops = {
-	.read		= cpu_type_read,
-	.llseek		= default_llseek,
-};
-
-
-static ssize_t enable_read(struct file *file, char __user *buf, size_t count, loff_t *offset)
-{
-	return oprofilefs_ulong_to_user(oprofile_started, buf, count, offset);
-}
-
-
-static ssize_t enable_write(struct file *file, char const __user *buf, size_t count, loff_t *offset)
-{
-	unsigned long val;
-	int retval;
-
-	if (*offset)
-		return -EINVAL;
-
-	retval = oprofilefs_ulong_from_user(&val, buf, count);
-	if (retval <= 0)
-		return retval;
-
-	retval = 0;
-	if (val)
-		retval = oprofile_start();
-	else
-		oprofile_stop();
-
-	if (retval)
-		return retval;
-	return count;
-}
-
-
-static const struct file_operations enable_fops = {
-	.read		= enable_read,
-	.write		= enable_write,
-	.llseek		= default_llseek,
-};
-
-
-static ssize_t dump_write(struct file *file, char const __user *buf, size_t count, loff_t *offset)
-{
-	wake_up_buffer_waiter();
-	return count;
-}
-
-
-static const struct file_operations dump_fops = {
-	.write		= dump_write,
-	.llseek		= noop_llseek,
-};
-
-void oprofile_create_files(struct dentry *root)
-{
-	/* reinitialize default values */
-	oprofile_buffer_size =		BUFFER_SIZE_DEFAULT;
-	oprofile_cpu_buffer_size =	CPU_BUFFER_SIZE_DEFAULT;
-	oprofile_buffer_watershed =	BUFFER_WATERSHED_DEFAULT;
-	oprofile_time_slice =		msecs_to_jiffies(TIME_SLICE_DEFAULT);
-
-	oprofilefs_create_file(root, "enable", &enable_fops);
-	oprofilefs_create_file_perm(root, "dump", &dump_fops, 0666);
-	oprofilefs_create_file(root, "buffer", &event_buffer_fops);
-	oprofilefs_create_ulong(root, "buffer_size", &oprofile_buffer_size);
-	oprofilefs_create_ulong(root, "buffer_watershed", &oprofile_buffer_watershed);
-	oprofilefs_create_ulong(root, "cpu_buffer_size", &oprofile_cpu_buffer_size);
-	oprofilefs_create_file(root, "cpu_type", &cpu_type_fops);
-	oprofilefs_create_file(root, "backtrace_depth", &depth_fops);
-	oprofilefs_create_file(root, "pointer_size", &pointer_size_fops);
-#ifdef CONFIG_OPROFILE_EVENT_MULTIPLEX
-	oprofilefs_create_file(root, "time_slice", &timeout_fops);
-#endif
-	oprofile_create_stats_files(root);
-	if (oprofile_ops.create_files)
-		oprofile_ops.create_files(root);
-}

drivers/oprofile/oprofile_perf.c

-// SPDX-License-Identifier: GPL-2.0
-/*
- * Copyright 2010 ARM Ltd.
- * Copyright 2012 Advanced Micro Devices, Inc., Robert Richter
- *
- * Perf-events backend for OProfile.
- */
-#include <linux/perf_event.h>
-#include <linux/platform_device.h>
-#include <linux/oprofile.h>
-#include <linux/slab.h>
-
-/*
- * Per performance monitor configuration as set via oprofilefs.
- */
-struct op_counter_config {
-	unsigned long count;
-	unsigned long enabled;
-	unsigned long event;
-	unsigned long unit_mask;
-	unsigned long kernel;
-	unsigned long user;
-	struct perf_event_attr attr;
-};
-
-static int oprofile_perf_enabled;
-static DEFINE_MUTEX(oprofile_perf_mutex);
-
-static struct op_counter_config *counter_config;
-static DEFINE_PER_CPU(struct perf_event **, perf_events);
-static int num_counters;
-
-/*
- * Overflow callback for oprofile.
- */
-static void op_overflow_handler(struct perf_event *event,
-			struct perf_sample_data *data, struct pt_regs *regs)
-{
-	int id;
-	u32 cpu = smp_processor_id();
-
-	for (id = 0; id < num_counters; ++id)
-		if (per_cpu(perf_events, cpu)[id] == event)
-			break;
-
-	if (id != num_counters)
-		oprofile_add_sample(regs, id);
-	else
-		pr_warn("oprofile: ignoring spurious overflow on cpu %u\n",
-			cpu);
-}
-
-/*
- * Called by oprofile_perf_setup to create perf attributes to mirror the oprofile
- * settings in counter_config. Attributes are created as `pinned' events and
- * so are permanently scheduled on the PMU.
- */
-static void op_perf_setup(void)
-{
-	int i;
-	u32 size = sizeof(struct perf_event_attr);
-	struct perf_event_attr *attr;
-
-	for (i = 0; i < num_counters; ++i) {
-		attr = &counter_config[i].attr;
-		memset(attr, 0, size);
-		attr->type		= PERF_TYPE_RAW;
-		attr->size		= size;
-		attr->config		= counter_config[i].event;
-		attr->sample_period	= counter_config[i].count;
-		attr->pinned		= 1;
-	}
-}
-
-static int op_create_counter(int cpu, int event)
-{
-	struct perf_event *pevent;
-
-	if (!counter_config[event].enabled || per_cpu(perf_events, cpu)[event])
-		return 0;
-
-	pevent = perf_event_create_kernel_counter(&counter_config[event].attr,
-						  cpu, NULL,
-						  op_overflow_handler, NULL);
-
-	if (IS_ERR(pevent))
-		return PTR_ERR(pevent);
-
-	if (pevent->state != PERF_EVENT_STATE_ACTIVE) {
-		perf_event_release_kernel(pevent);
-		pr_warn("oprofile: failed to enable event %d on CPU %d\n",
-			event, cpu);
-		return -EBUSY;
-	}
-
-	per_cpu(perf_events, cpu)[event] = pevent;
-
-	return 0;
-}
-
-static void op_destroy_counter(int cpu, int event)
-{
-	struct perf_event *pevent = per_cpu(perf_events, cpu)[event];
-
-	if (pevent) {
-		perf_event_release_kernel(pevent);
-		per_cpu(perf_events, cpu)[event] = NULL;
-	}
-}
-
-/*
- * Called by oprofile_perf_start to create active perf events based on the
- * perviously configured attributes.
- */
-static int op_perf_start(void)
-{
-	int cpu, event, ret = 0;
-
-	for_each_online_cpu(cpu) {
-		for (event = 0; event < num_counters; ++event) {
-			ret = op_create_counter(cpu, event);
-			if (ret)
-				return ret;
-		}
-	}
-
-	return ret;
-}
-
-/*
- * Called by oprofile_perf_stop at the end of a profiling run.
- */
-static void op_perf_stop(void)
-{
-	int cpu, event;
-
-	for_each_online_cpu(cpu)
-		for (event = 0; event < num_counters; ++event)
-			op_destroy_counter(cpu, event);
-}
-
-static int oprofile_perf_create_files(struct dentry *root)
-{
-	unsigned int i;
-
-	for (i = 0; i < num_counters; i++) {
-		struct dentry *dir;
-		char buf[4];
-
-		snprintf(buf, sizeof buf, "%d", i);
-		dir = oprofilefs_mkdir(root, buf);
-		oprofilefs_create_ulong(dir, "enabled", &counter_config[i].enabled);
-		oprofilefs_create_ulong(dir, "event", &counter_config[i].event);
-		oprofilefs_create_ulong(dir, "count", &counter_config[i].count);
-		oprofilefs_create_ulong(dir, "unit_mask", &counter_config[i].unit_mask);
-		oprofilefs_create_ulong(dir, "kernel", &counter_config[i].kernel);
-		oprofilefs_create_ulong(dir, "user", &counter_config[i].user);
-	}
-
-	return 0;
-}
-
-static int oprofile_perf_setup(void)
-{
-	raw_spin_lock(&oprofilefs_lock);
-	op_perf_setup();
-	raw_spin_unlock(&oprofilefs_lock);
-	return 0;
-}
-
-static int oprofile_perf_start(void)
-{
-	int ret = -EBUSY;
-
-	mutex_lock(&oprofile_perf_mutex);
-	if (!oprofile_perf_enabled) {
-		ret = 0;
-		op_perf_start();
-		oprofile_perf_enabled = 1;
-	}
-	mutex_unlock(&oprofile_perf_mutex);
-	return ret;
-}
-
-static void oprofile_perf_stop(void)
-{
-	mutex_lock(&oprofile_perf_mutex);
-	if (oprofile_perf_enabled)
-		op_perf_stop();
-	oprofile_perf_enabled = 0;
-	mutex_unlock(&oprofile_perf_mutex);
-}
-
-#ifdef CONFIG_PM
-
-static int oprofile_perf_suspend(struct platform_device *dev, pm_message_t state)
-{
-	mutex_lock(&oprofile_perf_mutex);
-	if (oprofile_perf_enabled)
-		op_perf_stop();
-	mutex_unlock(&oprofile_perf_mutex);
-	return 0;
-}
-
-static int oprofile_perf_resume(struct platform_device *dev)
-{
-	mutex_lock(&oprofile_perf_mutex);
-	if (oprofile_perf_enabled && op_perf_start())
-		oprofile_perf_enabled = 0;
-	mutex_unlock(&oprofile_perf_mutex);
-	return 0;
-}
-
-static struct platform_driver oprofile_driver = {
-	.driver		= {
-		.name		= "oprofile-perf",
-	},
-	.resume		= oprofile_perf_resume,
-	.suspend	= oprofile_perf_suspend,
-};
-
-static struct platform_device *oprofile_pdev;
-
-static int __init init_driverfs(void)
-{
-	int ret;
-
-	ret = platform_driver_register(&oprofile_driver);
-	if (ret)
-		return ret;
-
-	oprofile_pdev =	platform_device_register_simple(
-				oprofile_driver.driver.name, 0, NULL, 0);
-	if (IS_ERR(oprofile_pdev)) {
-		ret = PTR_ERR(oprofile_pdev);
-		platform_driver_unregister(&oprofile_driver);
-	}
-
-	return ret;
-}
-
-static void exit_driverfs(void)
-{
-	platform_device_unregister(oprofile_pdev);
-	platform_driver_unregister(&oprofile_driver);
-}
-
-#else
-
-static inline int  init_driverfs(void) { return 0; }
-static inline void exit_driverfs(void) { }
-
-#endif /* CONFIG_PM */
-
-void oprofile_perf_exit(void)
-{
-	int cpu, id;
-	struct perf_event *event;
-
-	for_each_possible_cpu(cpu) {
-		for (id = 0; id < num_counters; ++id) {
-			event = per_cpu(perf_events, cpu)[id];
-			if (event)
-				perf_event_release_kernel(event);
-		}
-
-		kfree(per_cpu(perf_events, cpu));
-	}
-
-	kfree(counter_config);
-	exit_driverfs();
-}
-
-int __init oprofile_perf_init(struct oprofile_operations *ops)
-{
-	int cpu, ret = 0;
-
-	ret = init_driverfs();
-	if (ret)
-		return ret;
-
-	num_counters = perf_num_counters();
-	if (num_counters <= 0) {
-		pr_info("oprofile: no performance counters\n");
-		ret = -ENODEV;
-		goto out;
-	}
-
-	counter_config = kcalloc(num_counters,
-			sizeof(struct op_counter_config), GFP_KERNEL);
-
-	if (!counter_config) {
-		pr_info("oprofile: failed to allocate %d "
-				"counters\n", num_counters);
-		ret = -ENOMEM;
-		num_counters = 0;
-		goto out;
-	}
-
-	for_each_possible_cpu(cpu) {
-		per_cpu(perf_events, cpu) = kcalloc(num_counters,
-				sizeof(struct perf_event *), GFP_KERNEL);
-		if (!per_cpu(perf_events, cpu)) {
-			pr_info("oprofile: failed to allocate %d perf events "
-					"for cpu %d\n", num_counters, cpu);
-			ret = -ENOMEM;
-			goto out;
-		}
-	}
-
-	ops->create_files	= oprofile_perf_create_files;
-	ops->setup		= oprofile_perf_setup;
-	ops->start		= oprofile_perf_start;
-	ops->stop		= oprofile_perf_stop;
-	ops->shutdown		= oprofile_perf_stop;
-	ops->cpu_type		= op_name_from_perf_id();
-
-	if (!ops->cpu_type)
-		ret = -ENODEV;
-	else
-		pr_info("oprofile: using %s\n", ops->cpu_type);
-
-out:
-	if (ret)
-		oprofile_perf_exit();
-
-	return ret;
-}

drivers/oprofile/oprofile_stats.c

-/**
- * @file oprofile_stats.c
- *
- * @remark Copyright 2002 OProfile authors
- * @remark Read the file COPYING
- *
- * @author John Levon
- */
-
-#include <linux/oprofile.h>
-#include <linux/smp.h>
-#include <linux/cpumask.h>
-#include <linux/threads.h>
-
-#include "oprofile_stats.h"
-#include "cpu_buffer.h"
-
-struct oprofile_stat_struct oprofile_stats;
-
-void oprofile_reset_stats(void)
-{
-	struct oprofile_cpu_buffer *cpu_buf;
-	int i;
-
-	for_each_possible_cpu(i) {
-		cpu_buf = &per_cpu(op_cpu_buffer, i);
-		cpu_buf->sample_received = 0;
-		cpu_buf->sample_lost_overflow = 0;
-		cpu_buf->backtrace_aborted = 0;
-		cpu_buf->sample_invalid_eip = 0;
-	}
-
-	atomic_set(&oprofile_stats.sample_lost_no_mm, 0);
-	atomic_set(&oprofile_stats.sample_lost_no_mapping, 0);
-	atomic_set(&oprofile_stats.event_lost_overflow, 0);
-	atomic_set(&oprofile_stats.bt_lost_no_mapping, 0);
-	atomic_set(&oprofile_stats.multiplex_counter, 0);
-}
-
-
-void oprofile_create_stats_files(struct dentry *root)
-{
-	struct oprofile_cpu_buffer *cpu_buf;
-	struct dentry *cpudir;
-	struct dentry *dir;
-	char buf[10];
-	int i;
-
-	dir = oprofilefs_mkdir(root, "stats");
-	if (!dir)
-		return;
-
-	for_each_possible_cpu(i) {
-		cpu_buf = &per_cpu(op_cpu_buffer, i);
-		snprintf(buf, 10, "cpu%d", i);
-		cpudir = oprofilefs_mkdir(dir, buf);
-
-		/* Strictly speaking access to these ulongs is racy,
-		 * but we can't simply lock them, and they are
-		 * informational only.
-		 */
-		oprofilefs_create_ro_ulong(cpudir, "sample_received",
-			&cpu_buf->sample_received);
-		oprofilefs_create_ro_ulong(cpudir, "sample_lost_overflow",
-			&cpu_buf->sample_lost_overflow);
-		oprofilefs_create_ro_ulong(cpudir, "backtrace_aborted",
-			&cpu_buf->backtrace_aborted);
-		oprofilefs_create_ro_ulong(cpudir, "sample_invalid_eip",
-			&cpu_buf->sample_invalid_eip);
-	}
-
-	oprofilefs_create_ro_atomic(dir, "sample_lost_no_mm",
-		&oprofile_stats.sample_lost_no_mm);
-	oprofilefs_create_ro_atomic(dir, "sample_lost_no_mapping",
-		&oprofile_stats.sample_lost_no_mapping);
-	oprofilefs_create_ro_atomic(dir, "event_lost_overflow",
-		&oprofile_stats.event_lost_overflow);
-	oprofilefs_create_ro_atomic(dir, "bt_lost_no_mapping",
-		&oprofile_stats.bt_lost_no_mapping);
-#ifdef CONFIG_OPROFILE_EVENT_MULTIPLEX
-	oprofilefs_create_ro_atomic(dir, "multiplex_counter",
-		&oprofile_stats.multiplex_counter);
-#endif
-}

drivers/oprofile/oprofile_stats.h

-/**
- * @file oprofile_stats.h
- *
- * @remark Copyright 2002 OProfile authors
- * @remark Read the file COPYING
- *
- * @author John Levon
- */
-
-#ifndef OPROFILE_STATS_H
-#define OPROFILE_STATS_H
-
-#include <linux/atomic.h>
-
-struct oprofile_stat_struct {
-	atomic_t sample_lost_no_mm;
-	atomic_t sample_lost_no_mapping;
-	atomic_t bt_lost_no_mapping;
-	atomic_t event_lost_overflow;
-	atomic_t multiplex_counter;
-};
-
-extern struct oprofile_stat_struct oprofile_stats;
-
-/* reset all stats to zero */
-void oprofile_reset_stats(void);
-
-struct dentry;
-
-/* create the stats/ dir */
-void oprofile_create_stats_files(struct dentry *root);
-
-#endif /* OPROFILE_STATS_H */

drivers/oprofile/oprofilefs.c

-/**
- * @file oprofilefs.c
- *
- * @remark Copyright 2002 OProfile authors
- * @remark Read the file COPYING
- *
- * @author John Levon
- *
- * A simple filesystem for configuration and
- * access of oprofile.
- */
-
-#include <linux/init.h>
-#include <linux/module.h>
-#include <linux/oprofile.h>
-#include <linux/fs.h>
-#include <linux/fs_context.h>
-#include <linux/pagemap.h>
-#include <linux/uaccess.h>
-
-#include "oprof.h"
-
-#define OPROFILEFS_MAGIC 0x6f70726f
-
-DEFINE_RAW_SPINLOCK(oprofilefs_lock);
-
-static struct inode *oprofilefs_get_inode(struct super_block *sb, int mode)
-{
-	struct inode *inode = new_inode(sb);
-
-	if (inode) {
-		inode->i_ino = get_next_ino();
-		inode->i_mode = mode;
-		inode->i_atime = inode->i_mtime = inode->i_ctime = current_time(inode);
-	}
-	return inode;
-}
-
-
-static const struct super_operations s_ops = {
-	.statfs		= simple_statfs,
-	.drop_inode 	= generic_delete_inode,
-};
-
-
-ssize_t oprofilefs_str_to_user(char const *str, char __user *buf, size_t count, loff_t *offset)
-{
-	return simple_read_from_buffer(buf, count, offset, str, strlen(str));
-}
-
-
-#define TMPBUFSIZE 50
-
-ssize_t oprofilefs_ulong_to_user(unsigned long val, char __user *buf, size_t count, loff_t *offset)
-{
-	char tmpbuf[TMPBUFSIZE];
-	size_t maxlen = snprintf(tmpbuf, TMPBUFSIZE, "%lu\n", val);
-	if (maxlen > TMPBUFSIZE)
-		maxlen = TMPBUFSIZE;
-	return simple_read_from_buffer(buf, count, offset, tmpbuf, maxlen);
-}
-
-
-/*
- * Note: If oprofilefs_ulong_from_user() returns 0, then *val remains
- * unchanged and might be uninitialized. This follows write syscall
- * implementation when count is zero: "If count is zero ... [and if]
- * no errors are detected, 0 will be returned without causing any
- * other effect." (man 2 write)
- */
-int oprofilefs_ulong_from_user(unsigned long *val, char const __user *buf, size_t count)
-{
-	char tmpbuf[TMPBUFSIZE];
-	unsigned long flags;
-
-	if (!count)
-		return 0;
-
-	if (count > TMPBUFSIZE - 1)
-		return -EINVAL;
-
-	memset(tmpbuf, 0x0, TMPBUFSIZE);
-
-	if (copy_from_user(tmpbuf, buf, count))
-		return -EFAULT;
-
-	raw_spin_lock_irqsave(&oprofilefs_lock, flags);
-	*val = simple_strtoul(tmpbuf, NULL, 0);
-	raw_spin_unlock_irqrestore(&oprofilefs_lock, flags);
-	return count;
-}
-
-
-static ssize_t ulong_read_file(struct file *file, char __user *buf, size_t count, loff_t *offset)
-{
-	unsigned long *val = file->private_data;
-	return oprofilefs_ulong_to_user(*val, buf, count, offset);
-}
-
-
-static ssize_t ulong_write_file(struct file *file, char const __user *buf, size_t count, loff_t *offset)
-{
-	unsigned long value;
-	int retval;
-
-	if (*offset)
-		return -EINVAL;
-
-	retval = oprofilefs_ulong_from_user(&value, buf, count);
-	if (retval <= 0)
-		return retval;
-
-	retval = oprofile_set_ulong(file->private_data, value);
-	if (retval)
-		return retval;
-
-	return count;
-}
-
-
-static const struct file_operations ulong_fops = {
-	.read		= ulong_read_file,
-	.write		= ulong_write_file,
-	.open		= simple_open,
-	.llseek		= default_llseek,
-};
-
-
-static const struct file_operations ulong_ro_fops = {
-	.read		= ulong_read_file,
-	.open		= simple_open,
-	.llseek		= default_llseek,
-};
-
-
-static int __oprofilefs_create_file(struct dentry *root, char const *name,
-	const struct file_operations *fops, int perm, void *priv)
-{
-	struct dentry *dentry;
-	struct inode *inode;
-
-	if (!root)
-		return -ENOMEM;
-
-	inode_lock(d_inode(root));
-	dentry = d_alloc_name(root, name);
-	if (!dentry) {
-		inode_unlock(d_inode(root));
-		return -ENOMEM;
-	}
-	inode = oprofilefs_get_inode(root->d_sb, S_IFREG | perm);
-	if (!inode) {
-		dput(dentry);
-		inode_unlock(d_inode(root));
-		return -ENOMEM;
-	}
-	inode->i_fop = fops;
-	inode->i_private = priv;
-	d_add(dentry, inode);
-	inode_unlock(d_inode(root));
-	return 0;
-}
-
-
-int oprofilefs_create_ulong(struct dentry *root,
-	char const *name, unsigned long *val)
-{
-	return __oprofilefs_create_file(root, name,
-					&ulong_fops, 0644, val);
-}
-
-
-int oprofilefs_create_ro_ulong(struct dentry *root,
-	char const *name, unsigned long *val)
-{
-	return __oprofilefs_create_file(root, name,
-					&ulong_ro_fops, 0444, val);
-}
-
-
-static ssize_t atomic_read_file(struct file *file, char __user *buf, size_t count, loff_t *offset)
-{
-	atomic_t *val = file->private_data;
-	return oprofilefs_ulong_to_user(atomic_read(val), buf, count, offset);
-}
-
-
-static const struct file_operations atomic_ro_fops = {
-	.read		= atomic_read_file,
-	.open		= simple_open,
-	.llseek		= default_llseek,
-};
-
-
-int oprofilefs_create_ro_atomic(struct dentry *root,
-	char const *name, atomic_t *val)
-{
-	return __oprofilefs_create_file(root, name,
-					&atomic_ro_fops, 0444, val);
-}
-
-
-int oprofilefs_create_file(struct dentry *root,
-	char const *name, const struct file_operations *fops)
-{
-	return __oprofilefs_create_file(root, name, fops, 0644, NULL);
-}
-
-
-int oprofilefs_create_file_perm(struct dentry *root,
-	char const *name, const struct file_operations *fops, int perm)
-{
-	return __oprofilefs_create_file(root, name, fops, perm, NULL);
-}
-
-
-struct dentry *oprofilefs_mkdir(struct dentry *parent, char const *name)
-{
-	struct dentry *dentry;
-	struct inode *inode;
-
-	inode_lock(d_inode(parent));
-	dentry = d_alloc_name(parent, name);
-	if (!dentry) {
-		inode_unlock(d_inode(parent));
-		return NULL;
-	}
-	inode = oprofilefs_get_inode(parent->d_sb, S_IFDIR | 0755);
-	if (!inode) {
-		dput(dentry);
-		inode_unlock(d_inode(parent));
-		return NULL;
-	}
-	inode->i_op = &simple_dir_inode_operations;
-	inode->i_fop = &simple_dir_operations;
-	d_add(dentry, inode);
-	inode_unlock(d_inode(parent));
-	return dentry;
-}
-
-
-static int oprofilefs_fill_super(struct super_block *sb, struct fs_context *fc)
-{
-	struct inode *root_inode;
-
-	sb->s_blocksize = PAGE_SIZE;
-	sb->s_blocksize_bits = PAGE_SHIFT;
-	sb->s_magic = OPROFILEFS_MAGIC;
-	sb->s_op = &s_ops;
-	sb->s_time_gran = 1;
-
-	root_inode = oprofilefs_get_inode(sb, S_IFDIR | 0755);
-	if (!root_inode)
-		return -ENOMEM;
-	root_inode->i_op = &simple_dir_inode_operations;
-	root_inode->i_fop = &simple_dir_operations;
-	sb->s_root = d_make_root(root_inode);
-	if (!sb->s_root)
-		return -ENOMEM;
-
-	oprofile_create_files(sb->s_root);
-
-	// FIXME: verify kill_litter_super removes our dentries
-	return 0;
-}
-
-static int oprofilefs_get_tree(struct fs_context *fc)
-{
-	return get_tree_single(fc, oprofilefs_fill_super);
-}
-
-static const struct fs_context_operations oprofilefs_context_ops = {
-	.get_tree	= oprofilefs_get_tree,
-};
-
-static int oprofilefs_init_fs_context(struct fs_context *fc)
-{
-	fc->ops = &oprofilefs_context_ops;
-	return 0;
-}
-
-static struct file_system_type oprofilefs_type = {
-	.owner		= THIS_MODULE,
-	.name		= "oprofilefs",
-	.init_fs_context = oprofilefs_init_fs_context,
-	.kill_sb	= kill_litter_super,
-};
-MODULE_ALIAS_FS("oprofilefs");
-
-
-int __init oprofilefs_register(void)
-{
-	return register_filesystem(&oprofilefs_type);
-}
-
-
-void __exit oprofilefs_unregister(void)
-{
-	unregister_filesystem(&oprofilefs_type);
-}

drivers/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/notifier.h>
-#include <linux/smp.h>
-#include <linux/oprofile.h>
-#include <linux/profile.h>
-#include <linux/init.h>
-#include <linux/cpu.h>
-#include <linux/hrtimer.h>
-#include <asm/irq_regs.h>
-#include <asm/ptrace.h>
-
-#include "oprof.h"
-
-static DEFINE_PER_CPU(struct hrtimer, oprofile_hrtimer);
-static int ctr_running;
-
-static enum hrtimer_restart oprofile_hrtimer_notify(struct hrtimer *hrtimer)
-{
-	oprofile_add_sample(get_irq_regs(), 0);
-	hrtimer_forward_now(hrtimer, ns_to_ktime(TICK_NSEC));
-	return HRTIMER_RESTART;
-}
-
-static void __oprofile_hrtimer_start(void *unused)
-{
-	struct hrtimer *hrtimer = this_cpu_ptr(&oprofile_hrtimer);
-
-	if (!ctr_running)
-		return;
-
-	hrtimer_init(hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
-	hrtimer->function = oprofile_hrtimer_notify;
-
-	hrtimer_start(hrtimer, ns_to_ktime(TICK_NSEC),
-		      HRTIMER_MODE_REL_PINNED);
-}
-
-static int oprofile_hrtimer_start(void)
-{
-	get_online_cpus();
-	ctr_running = 1;
-	on_each_cpu(__oprofile_hrtimer_start, NULL, 1);
-	put_online_cpus();
-	return 0;
-}
-
-static void __oprofile_hrtimer_stop(int cpu)
-{
-	struct hrtimer *hrtimer = &per_cpu(oprofile_hrtimer, cpu);
-
-	if (!ctr_running)
-		return;
-
-	hrtimer_cancel(hrtimer);
-}
-
-static void oprofile_hrtimer_stop(void)
-{
-	int cpu;
-
-	get_online_cpus();
-	for_each_online_cpu(cpu)
-		__oprofile_hrtimer_stop(cpu);
-	ctr_running = 0;
-	put_online_cpus();
-}
-
-static int oprofile_timer_online(unsigned int cpu)
-{
-	local_irq_disable();
-	__oprofile_hrtimer_start(NULL);
-	local_irq_enable();
-	return 0;
-}
-
-static int oprofile_timer_prep_down(unsigned int cpu)
-{
-	__oprofile_hrtimer_stop(cpu);
-	return 0;
-}
-
-static enum cpuhp_state hp_online;
-
-static int oprofile_hrtimer_setup(void)
-{
-	int ret;
-
-	ret = cpuhp_setup_state_nocalls(CPUHP_AP_ONLINE_DYN,
-					"oprofile/timer:online",
-					oprofile_timer_online,
-					oprofile_timer_prep_down);
-	if (ret < 0)
-		return ret;
-	hp_online = ret;
-	return 0;
-}
-
-static void oprofile_hrtimer_shutdown(void)
-{
-	cpuhp_remove_state_nocalls(hp_online);
-}
-
-int oprofile_timer_init(struct oprofile_operations *ops)
-{
-	ops->create_files	= NULL;
-	ops->setup		= oprofile_hrtimer_setup;
-	ops->shutdown		= oprofile_hrtimer_shutdown;
-	ops->start		= oprofile_hrtimer_start;
-	ops->stop		= oprofile_hrtimer_stop;
-	ops->cpu_type		= "timer";
-	printk(KERN_INFO "oprofile: using timer interrupt.\n");
-	return 0;
-}

include/linux/oprofile.h

-/**
- * @file oprofile.h
- *
- * API for machine-specific interrupts to interface
- * to oprofile.
- *
- * @remark Copyright 2002 OProfile authors
- * @remark Read the file COPYING
- *
- * @author John Levon <levon@movementarian.org>
- */
-
-#ifndef OPROFILE_H
-#define OPROFILE_H
-
-#include <linux/types.h>
-#include <linux/spinlock.h>
-#include <linux/init.h>
-#include <linux/errno.h>
-#include <linux/printk.h>
-#include <linux/atomic.h>
- 
-/* Each escaped entry is prefixed by ESCAPE_CODE
- * then one of the following codes, then the
- * relevant data.
- * These #defines live in this file so that arch-specific
- * buffer sync'ing code can access them.
- */
-#define ESCAPE_CODE			~0UL
-#define CTX_SWITCH_CODE			1
-#define CPU_SWITCH_CODE			2
-#define COOKIE_SWITCH_CODE		3
-#define KERNEL_ENTER_SWITCH_CODE	4
-#define KERNEL_EXIT_SWITCH_CODE		5
-#define MODULE_LOADED_CODE		6
-#define CTX_TGID_CODE			7
-#define TRACE_BEGIN_CODE		8
-#define TRACE_END_CODE			9
-#define XEN_ENTER_SWITCH_CODE		10
-#define SPU_PROFILING_CODE		11
-#define SPU_CTX_SWITCH_CODE		12
-#define IBS_FETCH_CODE			13
-#define IBS_OP_CODE			14
-
-struct dentry;
-struct file_operations;
-struct pt_regs;
- 
-/* Operations structure to be filled in */
-struct oprofile_operations {
-	/* create any necessary configuration files in the oprofile fs.
-	 * Optional. */
-	int (*create_files)(struct dentry * root);
-	/* Do any necessary interrupt setup. Optional. */
-	int (*setup)(void);
-	/* Do any necessary interrupt shutdown. Optional. */
-	void (*shutdown)(void);
-	/* Start delivering interrupts. */
-	int (*start)(void);
-	/* Stop delivering interrupts. */
-	void (*stop)(void);
-	/* Arch-specific buffer sync functions.
-	 * Return value = 0:  Success
-	 * Return value = -1: Failure
-	 * Return value = 1:  Run generic sync function
-	 */
-	int (*sync_start)(void);
-	int (*sync_stop)(void);
-
-	/* Initiate a stack backtrace. Optional. */
-	void (*backtrace)(struct pt_regs * const regs, unsigned int depth);
-
-	/* Multiplex between different events. Optional. */
-	int (*switch_events)(void);
-	/* CPU identification string. */
-	char * cpu_type;
-};
-
-/**
- * One-time initialisation. *ops must be set to a filled-in
- * operations structure. This is called even in timer interrupt
- * mode so an arch can set a backtrace callback.
- *
- * If an error occurs, the fields should be left untouched.
- */
-int oprofile_arch_init(struct oprofile_operations * ops);
- 
-/**
- * One-time exit/cleanup for the arch.
- */
-void oprofile_arch_exit(void);
-
-/**
- * Add a sample. This may be called from any context.
- */
-void oprofile_add_sample(struct pt_regs * const regs, unsigned long event);
-
-/**
- * Add an extended sample.  Use this when the PC is not from the regs, and
- * we cannot determine if we're in kernel mode from the regs.
- *
- * This function does perform a backtrace.
- *
- */
-void oprofile_add_ext_sample(unsigned long pc, struct pt_regs * const regs,
-				unsigned long event, int is_kernel);
-
-/**
- * Add an hardware sample.
- */
-void oprofile_add_ext_hw_sample(unsigned long pc, struct pt_regs * const regs,
-	unsigned long event, int is_kernel,
-	struct task_struct *task);
-
-/* Use this instead when the PC value is not from the regs. Doesn't
- * backtrace. */
-void oprofile_add_pc(unsigned long pc, int is_kernel, unsigned long event);
-
-/* add a backtrace entry, to be called from the ->backtrace callback */
-void oprofile_add_trace(unsigned long eip);
-
-
-/**
- * Create a file of the given name as a child of the given root, with
- * the specified file operations.
- */
-int oprofilefs_create_file(struct dentry * root,
-	char const * name, const struct file_operations * fops);
-
-int oprofilefs_create_file_perm(struct dentry * root,
-	char const * name, const struct file_operations * fops, int perm);
- 
-/** Create a file for read/write access to an unsigned long. */
-int oprofilefs_create_ulong(struct dentry * root,
-	char const * name, ulong * val);
- 
-/** Create a file for read-only access to an unsigned long. */
-int oprofilefs_create_ro_ulong(struct dentry * root,
-	char const * name, ulong * val);
- 
-/** Create a file for read-only access to an atomic_t. */
-int oprofilefs_create_ro_atomic(struct dentry * root,
-	char const * name, atomic_t * val);
- 
-/** create a directory */
-struct dentry *oprofilefs_mkdir(struct dentry *parent, char const *name);
-
-/**
- * Write the given asciz string to the given user buffer @buf, updating *offset
- * appropriately. Returns bytes written or -EFAULT.
- */
-ssize_t oprofilefs_str_to_user(char const * str, char __user * buf, size_t count, loff_t * offset);
-
-/**
- * Convert an unsigned long value into ASCII and copy it to the user buffer @buf,
- * updating *offset appropriately. Returns bytes written or -EFAULT.
- */
-ssize_t oprofilefs_ulong_to_user(unsigned long val, char __user * buf, size_t count, loff_t * offset);
-
-/**
- * Read an ASCII string for a number from a userspace buffer and fill *val on success.
- * Returns 0 on success, < 0 on error.
- */
-int oprofilefs_ulong_from_user(unsigned long * val, char const __user * buf, size_t count);
-
-/** lock for read/write safety */
-extern raw_spinlock_t oprofilefs_lock;
-
-/**
- * Add the contents of a circular buffer to the event buffer.
- */
-void oprofile_put_buff(unsigned long *buf, unsigned int start,
-			unsigned int stop, unsigned int max);
-
-unsigned long oprofile_get_cpu_buffer_size(void);
-void oprofile_cpu_buffer_inc_smpl_lost(void);
- 
-/* cpu buffer functions */
-
-struct op_sample;
-
-struct op_entry {
-	struct ring_buffer_event *event;
-	struct op_sample *sample;
-	unsigned long size;
-	unsigned long *data;
-};
-
-void oprofile_write_reserve(struct op_entry *entry,
-			    struct pt_regs * const regs,
-			    unsigned long pc, int code, int size);
-int oprofile_add_data(struct op_entry *entry, unsigned long val);
-int oprofile_add_data64(struct op_entry *entry, u64 val);
-int oprofile_write_commit(struct op_entry *entry);
-
-#ifdef CONFIG_HW_PERF_EVENTS
-int __init oprofile_perf_init(struct oprofile_operations *ops);
-void oprofile_perf_exit(void);
-char *op_name_from_perf_id(void);
-#else
-static inline int __init oprofile_perf_init(struct oprofile_operations *ops)
-{
-	pr_info("oprofile: hardware counters not available\n");
-	return -ENODEV;
-}
-static inline void oprofile_perf_exit(void) { }
-#endif /* CONFIG_HW_PERF_EVENTS */
-
-#endif /* OPROFILE_H */

init/Kconfig

@@ -2024,7 +2024,7 @@ config PROFILING
 	bool "Profiling support"
 	help
 	  Say Y here to enable the extended profiling support mechanisms used
-	  by profilers such as OProfile.
+	  by profilers.
 
 #
 # Place an empty function call at each tracepoint site. Can be