1 files changed, 174 insertions, 2 deletions

diff --git a/arch/s390/oprofile/init.c b/arch/s390/oprofile/init.c
index 7a995113b918..0e358c2cffeb 100644
--- a/arch/s390/oprofile/init.c
+++ b/arch/s390/oprofile/init.c
@@ -4,23 +4,195 @@
  * S390 Version
  *   Copyright (C) 2003 IBM Deutschland Entwicklung GmbH, IBM Corporation
  *   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)
  *
- * @remark Copyright 2002 OProfile authors
+ * @remark Copyright 2002-2011 OProfile authors
  */
 
 #include <linux/oprofile.h>
 #include <linux/init.h>
 #include <linux/errno.h>
+#include <linux/oprofile.h>
+#include <linux/errno.h>
+#include <linux/fs.h>
 
+#include "../../../drivers/oprofile/oprof.h"
 
 extern void s390_backtrace(struct pt_regs * const regs, unsigned int depth);
 
-int __init oprofile_arch_init(struct oprofile_operations* ops)
+#ifdef CONFIG_64BIT
+
+#include "hwsampler.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_file;
+static int hwsampler_running;   /* start_mutex must be held to change */
+
+static struct oprofile_operations timer_ops;
+
+static int oprofile_hwsampler_start(void)
+{
+        int retval;
+
+        hwsampler_running = hwsampler_file;
+
+        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;
+}
+
+static ssize_t hwsampler_read(struct file *file, char __user *buf,
+                size_t count, loff_t *offset)
+{
+        return oprofilefs_ulong_to_user(hwsampler_file, 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)
+                return retval;
+
+        if (oprofile_started)
+                /*
+                 * save to do without locking as we set
+                 * hwsampler_running in start() when start_mutex is
+                 * held
+                 */
+                return -EBUSY;
+
+        hwsampler_file = val;
+
+        return count;
+}
+
+static const struct file_operations hwsampler_fops = {
+        .read           = hwsampler_read,
+        .write          = hwsampler_write,
+};
+
+static int oprofile_create_hwsampling_files(struct super_block *sb,
+                                                struct dentry *root)
+{
+        struct dentry *hw_dir;
+
+        /* reinitialize default values */
+        hwsampler_file = 1;
+
+        hw_dir = oprofilefs_mkdir(sb, root, "hwsampling");
+        if (!hw_dir)
+                return -EINVAL;
+
+        oprofilefs_create_file(sb, hw_dir, "hwsampler", &hwsampler_fops);
+        oprofilefs_create_ulong(sb, hw_dir, "hw_interval",
+                                &oprofile_hw_interval);
+        oprofilefs_create_ro_ulong(sb, hw_dir, "hw_min_interval",
+                                &oprofile_min_interval);
+        oprofilefs_create_ro_ulong(sb, hw_dir, "hw_max_interval",
+                                &oprofile_max_interval);
+        oprofilefs_create_ulong(sb, hw_dir, "hw_sdbt_blocks",
+                                &oprofile_sdbt_blocks);
+
+        return 0;
+}
+
+static int oprofile_hwsampler_init(struct oprofile_operations *ops)
+{
+        if (hwsampler_setup())
+                return -ENODEV;
+
+        /*
+         * create hwsampler files only if hwsampler_setup() succeeds.
+         */
+        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;
+
+        if (oprofile_timer_init(ops))
+                return -ENODEV;
+
+        printk(KERN_INFO "oprofile: using hardware sampling\n");
+
+        memcpy(&timer_ops, ops, sizeof(timer_ops));
+
+        ops->start = oprofile_hwsampler_start;
+        ops->stop = oprofile_hwsampler_stop;
+        ops->create_files = oprofile_create_hwsampling_files;
+
+        return 0;
+}
+
+static void oprofile_hwsampler_exit(void)
+{
+        oprofile_timer_exit();
+        hwsampler_shutdown();
+}
+
+#endif /* CONFIG_64BIT */
+
+int __init oprofile_arch_init(struct oprofile_operations *ops)
 {
         ops->backtrace = s390_backtrace;
+
+#ifdef CONFIG_64BIT
+        return oprofile_hwsampler_init(ops);
+#else
         return -ENODEV;
+#endif
 }
 
 void oprofile_arch_exit(void)
 {
+#ifdef CONFIG_64BIT
+        oprofile_hwsampler_exit();
+#endif
 }