From 1a960b402a51d80abf54e3f8e4972374ffe5f22d Mon Sep 17 00:00:00 2001 From: Jason Yeh Date: Wed, 23 Jul 2008 23:05:53 +0200 Subject: Oprofile Multiplexing Patch This patch introduces multiplexing support for the Oprofile kernel module. It basically adds a new function pointer in oprofile_operator allowing each architecture to supply its callback to switch between different sets of event when the timer expires. Userspace tools can modify the time slice through /dev/oprofile/time_slice. It also modifies the number of counters exposed to the userspace through /dev/oprofile. For example, the number of counters for AMD CPUs are changed to 32 and multiplexed in the sets of 4. Signed-off-by: Jason Yeh Signed-off-by: Robert Richter Cc: oprofile-list Signed-off-by: Ingo Molnar --- drivers/oprofile/oprofile_files.c | 39 +++++++++++++++++++++++++++++++++++++-- 1 file changed, 37 insertions(+), 2 deletions(-) (limited to 'drivers/oprofile/oprofile_files.c') diff --git a/drivers/oprofile/oprofile_files.c b/drivers/oprofile/oprofile_files.c index ef953ba5ab6..cc4f5a1f8ef 100644 --- a/drivers/oprofile/oprofile_files.c +++ b/drivers/oprofile/oprofile_files.c @@ -9,6 +9,7 @@ #include #include +#include #include "event_buffer.h" #include "oprofile_stats.h" @@ -18,6 +19,40 @@ unsigned long fs_buffer_size = 131072; unsigned long fs_cpu_buffer_size = 8192; unsigned long fs_buffer_watershed = 32768; /* FIXME: tune */ +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(timeout_jiffies), + 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) + 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, +}; + + static ssize_t depth_read(struct file * file, char __user * buf, size_t count, loff_t * offset) { return oprofilefs_ulong_to_user(backtrace_depth, buf, count, offset); @@ -85,11 +120,10 @@ static ssize_t enable_write(struct file * file, char const __user * buf, size_t if (*offset) return -EINVAL; - retval = oprofilefs_ulong_from_user(&val, buf, count); if (retval) return retval; - + if (val) retval = oprofile_start(); else @@ -129,6 +163,7 @@ void oprofile_create_files(struct super_block * sb, struct dentry * root) oprofilefs_create_file(sb, root, "cpu_type", &cpu_type_fops); oprofilefs_create_file(sb, root, "backtrace_depth", &depth_fops); oprofilefs_create_file(sb, root, "pointer_size", &pointer_size_fops); + oprofilefs_create_file(sb, root, "timeout_ms", &timeout_fops); oprofile_create_stats_files(sb, root); if (oprofile_ops.create_files) oprofile_ops.create_files(sb, root); -- cgit v1.2.3