linux/arch/s390/oprofile/init.c
Heiko Carstens a53c8fab3f s390/comments: unify copyright messages and remove file names
Remove the file name from the comment at top of many files. In most
cases the file name was wrong anyway, so it's rather pointless.

Also unify the IBM copyright statement. We did have a lot of sightly
different statements and wanted to change them one after another
whenever a file gets touched. However that never happened. Instead
people start to take the old/"wrong" statements to use as a template
for new files.
So unify all of them in one go.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2012-07-20 11:15:04 +02:00

508 lines
12 KiB
C

/*
* S390 Version
* Copyright IBM Corp. 2002, 2011
* Author(s): Thomas Spatzier (tspat@de.ibm.com)
* Author(s): Mahesh Salgaonkar (mahesh@linux.vnet.ibm.com)
* Author(s): Heinz Graalfs (graalfs@linux.vnet.ibm.com)
* Author(s): Andreas Krebbel (krebbel@linux.vnet.ibm.com)
*
* @remark Copyright 2002-2011 OProfile authors
*/
#include <linux/oprofile.h>
#include <linux/init.h>
#include <linux/errno.h>
#include <linux/fs.h>
#include <linux/module.h>
#include <asm/processor.h>
#include "../../../drivers/oprofile/oprof.h"
extern void s390_backtrace(struct pt_regs * const regs, unsigned int depth);
#ifdef CONFIG_64BIT
#include "hwsampler.h"
#include "op_counter.h"
#define DEFAULT_INTERVAL 4127518
#define DEFAULT_SDBT_BLOCKS 1
#define DEFAULT_SDB_BLOCKS 511
static unsigned long oprofile_hw_interval = DEFAULT_INTERVAL;
static unsigned long oprofile_min_interval;
static unsigned long oprofile_max_interval;
static unsigned long oprofile_sdbt_blocks = DEFAULT_SDBT_BLOCKS;
static unsigned long oprofile_sdb_blocks = DEFAULT_SDB_BLOCKS;
static int hwsampler_enabled;
static int hwsampler_running; /* start_mutex must be held to change */
static int hwsampler_available;
static struct oprofile_operations timer_ops;
struct op_counter_config counter_config;
enum __force_cpu_type {
reserved = 0, /* do not force */
timer,
};
static int force_cpu_type;
static int set_cpu_type(const char *str, struct kernel_param *kp)
{
if (!strcmp(str, "timer")) {
force_cpu_type = timer;
printk(KERN_INFO "oprofile: forcing timer to be returned "
"as cpu type\n");
} else {
force_cpu_type = 0;
}
return 0;
}
module_param_call(cpu_type, set_cpu_type, NULL, NULL, 0);
MODULE_PARM_DESC(cpu_type, "Force legacy basic mode sampling"
"(report cpu_type \"timer\"");
static int oprofile_hwsampler_start(void)
{
int retval;
hwsampler_running = hwsampler_enabled;
if (!hwsampler_running)
return timer_ops.start();
retval = hwsampler_allocate(oprofile_sdbt_blocks, oprofile_sdb_blocks);
if (retval)
return retval;
retval = hwsampler_start_all(oprofile_hw_interval);
if (retval)
hwsampler_deallocate();
return retval;
}
static void oprofile_hwsampler_stop(void)
{
if (!hwsampler_running) {
timer_ops.stop();
return;
}
hwsampler_stop_all();
hwsampler_deallocate();
return;
}
/*
* File ops used for:
* /dev/oprofile/0/enabled
* /dev/oprofile/hwsampling/hwsampler (cpu_type = timer)
*/
static ssize_t hwsampler_read(struct file *file, char __user *buf,
size_t count, loff_t *offset)
{
return oprofilefs_ulong_to_user(hwsampler_enabled, buf, count, offset);
}
static ssize_t hwsampler_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;
if (val != 0 && val != 1)
return -EINVAL;
if (oprofile_started)
/*
* save to do without locking as we set
* hwsampler_running in start() when start_mutex is
* held
*/
return -EBUSY;
hwsampler_enabled = val;
return count;
}
static const struct file_operations hwsampler_fops = {
.read = hwsampler_read,
.write = hwsampler_write,
};
/*
* File ops used for:
* /dev/oprofile/0/count
* /dev/oprofile/hwsampling/hw_interval (cpu_type = timer)
*
* Make sure that the value is within the hardware range.
*/
static ssize_t hw_interval_read(struct file *file, char __user *buf,
size_t count, loff_t *offset)
{
return oprofilefs_ulong_to_user(oprofile_hw_interval, buf,
count, offset);
}
static ssize_t hw_interval_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)
return retval;
if (val < oprofile_min_interval)
oprofile_hw_interval = oprofile_min_interval;
else if (val > oprofile_max_interval)
oprofile_hw_interval = oprofile_max_interval;
else
oprofile_hw_interval = val;
return count;
}
static const struct file_operations hw_interval_fops = {
.read = hw_interval_read,
.write = hw_interval_write,
};
/*
* File ops used for:
* /dev/oprofile/0/event
* Only a single event with number 0 is supported with this counter.
*
* /dev/oprofile/0/unit_mask
* This is a dummy file needed by the user space tools.
* No value other than 0 is accepted or returned.
*/
static ssize_t hwsampler_zero_read(struct file *file, char __user *buf,
size_t count, loff_t *offset)
{
return oprofilefs_ulong_to_user(0, buf, count, offset);
}
static ssize_t hwsampler_zero_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)
return retval;
if (val != 0)
return -EINVAL;
return count;
}
static const struct file_operations zero_fops = {
.read = hwsampler_zero_read,
.write = hwsampler_zero_write,
};
/* /dev/oprofile/0/kernel file ops. */
static ssize_t hwsampler_kernel_read(struct file *file, char __user *buf,
size_t count, loff_t *offset)
{
return oprofilefs_ulong_to_user(counter_config.kernel,
buf, count, offset);
}
static ssize_t hwsampler_kernel_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)
return retval;
if (val != 0 && val != 1)
return -EINVAL;
counter_config.kernel = val;
return count;
}
static const struct file_operations kernel_fops = {
.read = hwsampler_kernel_read,
.write = hwsampler_kernel_write,
};
/* /dev/oprofile/0/user file ops. */
static ssize_t hwsampler_user_read(struct file *file, char __user *buf,
size_t count, loff_t *offset)
{
return oprofilefs_ulong_to_user(counter_config.user,
buf, count, offset);
}
static ssize_t hwsampler_user_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)
return retval;
if (val != 0 && val != 1)
return -EINVAL;
counter_config.user = val;
return count;
}
static const struct file_operations user_fops = {
.read = hwsampler_user_read,
.write = hwsampler_user_write,
};
/*
* File ops used for: /dev/oprofile/timer/enabled
* The value always has to be the inverted value of hwsampler_enabled. So
* no separate variable is created. That way we do not need locking.
*/
static ssize_t timer_enabled_read(struct file *file, char __user *buf,
size_t count, loff_t *offset)
{
return oprofilefs_ulong_to_user(!hwsampler_enabled, buf, count, offset);
}
static ssize_t timer_enabled_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)
return retval;
if (val != 0 && val != 1)
return -EINVAL;
/* Timer cannot be disabled without having hardware sampling. */
if (val == 0 && !hwsampler_available)
return -EINVAL;
if (oprofile_started)
/*
* save to do without locking as we set
* hwsampler_running in start() when start_mutex is
* held
*/
return -EBUSY;
hwsampler_enabled = !val;
return count;
}
static const struct file_operations timer_enabled_fops = {
.read = timer_enabled_read,
.write = timer_enabled_write,
};
static int oprofile_create_hwsampling_files(struct super_block *sb,
struct dentry *root)
{
struct dentry *dir;
dir = oprofilefs_mkdir(sb, root, "timer");
if (!dir)
return -EINVAL;
oprofilefs_create_file(sb, dir, "enabled", &timer_enabled_fops);
if (!hwsampler_available)
return 0;
/* reinitialize default values */
hwsampler_enabled = 1;
counter_config.kernel = 1;
counter_config.user = 1;
if (!force_cpu_type) {
/*
* Create the counter file system. A single virtual
* counter is created which can be used to
* enable/disable hardware sampling dynamically from
* user space. The user space will configure a single
* counter with a single event. The value of 'event'
* and 'unit_mask' are not evaluated by the kernel code
* and can only be set to 0.
*/
dir = oprofilefs_mkdir(sb, root, "0");
if (!dir)
return -EINVAL;
oprofilefs_create_file(sb, dir, "enabled", &hwsampler_fops);
oprofilefs_create_file(sb, dir, "event", &zero_fops);
oprofilefs_create_file(sb, dir, "count", &hw_interval_fops);
oprofilefs_create_file(sb, dir, "unit_mask", &zero_fops);
oprofilefs_create_file(sb, dir, "kernel", &kernel_fops);
oprofilefs_create_file(sb, dir, "user", &user_fops);
oprofilefs_create_ulong(sb, dir, "hw_sdbt_blocks",
&oprofile_sdbt_blocks);
} else {
/*
* Hardware sampling can be used but the cpu_type is
* forced to timer in order to deal with legacy user
* space tools. The /dev/oprofile/hwsampling fs is
* provided in that case.
*/
dir = oprofilefs_mkdir(sb, root, "hwsampling");
if (!dir)
return -EINVAL;
oprofilefs_create_file(sb, dir, "hwsampler",
&hwsampler_fops);
oprofilefs_create_file(sb, dir, "hw_interval",
&hw_interval_fops);
oprofilefs_create_ro_ulong(sb, dir, "hw_min_interval",
&oprofile_min_interval);
oprofilefs_create_ro_ulong(sb, dir, "hw_max_interval",
&oprofile_max_interval);
oprofilefs_create_ulong(sb, dir, "hw_sdbt_blocks",
&oprofile_sdbt_blocks);
}
return 0;
}
static int oprofile_hwsampler_init(struct oprofile_operations *ops)
{
/*
* Initialize the timer mode infrastructure as well in order
* to be able to switch back dynamically. oprofile_timer_init
* is not supposed to fail.
*/
if (oprofile_timer_init(ops))
BUG();
memcpy(&timer_ops, ops, sizeof(timer_ops));
ops->create_files = oprofile_create_hwsampling_files;
/*
* If the user space tools do not support newer cpu types,
* the force_cpu_type module parameter
* can be used to always return \"timer\" as cpu type.
*/
if (force_cpu_type != timer) {
struct cpuid id;
get_cpu_id (&id);
switch (id.machine) {
case 0x2097: case 0x2098: ops->cpu_type = "s390/z10"; break;
case 0x2817: case 0x2818: ops->cpu_type = "s390/z196"; break;
default: return -ENODEV;
}
}
if (hwsampler_setup())
return -ENODEV;
/*
* Query the range for the sampling interval from the
* hardware.
*/
oprofile_min_interval = hwsampler_query_min_interval();
if (oprofile_min_interval == 0)
return -ENODEV;
oprofile_max_interval = hwsampler_query_max_interval();
if (oprofile_max_interval == 0)
return -ENODEV;
/* The initial value should be sane */
if (oprofile_hw_interval < oprofile_min_interval)
oprofile_hw_interval = oprofile_min_interval;
if (oprofile_hw_interval > oprofile_max_interval)
oprofile_hw_interval = oprofile_max_interval;
printk(KERN_INFO "oprofile: System z hardware sampling "
"facility found.\n");
ops->start = oprofile_hwsampler_start;
ops->stop = oprofile_hwsampler_stop;
return 0;
}
static void oprofile_hwsampler_exit(void)
{
hwsampler_shutdown();
}
#endif /* CONFIG_64BIT */
int __init oprofile_arch_init(struct oprofile_operations *ops)
{
ops->backtrace = s390_backtrace;
#ifdef CONFIG_64BIT
/*
* -ENODEV is not reported to the caller. The module itself
* will use the timer mode sampling as fallback and this is
* always available.
*/
hwsampler_available = oprofile_hwsampler_init(ops) == 0;
return 0;
#else
return -ENODEV;
#endif
}
void oprofile_arch_exit(void)
{
#ifdef CONFIG_64BIT
oprofile_hwsampler_exit();
#endif
}