summaryrefslogtreecommitdiff
path: root/arch/cris/kernel/profile.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/cris/kernel/profile.c')
-rw-r--r--arch/cris/kernel/profile.c73
1 files changed, 73 insertions, 0 deletions
diff --git a/arch/cris/kernel/profile.c b/arch/cris/kernel/profile.c
new file mode 100644
index 000000000000..69c52189f044
--- /dev/null
+++ b/arch/cris/kernel/profile.c
@@ -0,0 +1,73 @@
+#include <linux/init.h>
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/proc_fs.h>
+#include <linux/types.h>
+#include <asm/ptrace.h>
+#include <asm/uaccess.h>
+
+#define SAMPLE_BUFFER_SIZE 8192
+
+static char* sample_buffer;
+static char* sample_buffer_pos;
+static int prof_running = 0;
+
+void
+cris_profile_sample(struct pt_regs* regs)
+{
+ if (!prof_running)
+ return;
+ if (user_mode(regs))
+ *(unsigned int*)sample_buffer_pos = current->pid;
+ else
+ *(unsigned int*)sample_buffer_pos = 0;
+ *(unsigned int*)(sample_buffer_pos + 4) = instruction_pointer(regs);
+ sample_buffer_pos += 8;
+ if (sample_buffer_pos == sample_buffer + SAMPLE_BUFFER_SIZE)
+ sample_buffer_pos = sample_buffer;
+}
+
+static ssize_t
+read_cris_profile(struct file *file, char __user *buf, size_t count, loff_t *ppos)
+{
+ unsigned long p = *ppos;
+ if (p > SAMPLE_BUFFER_SIZE)
+ return 0;
+ if (p + count > SAMPLE_BUFFER_SIZE)
+ count = SAMPLE_BUFFER_SIZE - p;
+ if (copy_to_user(buf, sample_buffer + p,count))
+ return -EFAULT;
+ memset(sample_buffer + p, 0, count);
+ *ppos += count;
+ return count;
+}
+
+static ssize_t
+write_cris_profile(struct file *file, const char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ sample_buffer_pos = sample_buffer;
+ memset(sample_buffer, 0, SAMPLE_BUFFER_SIZE);
+}
+
+static struct file_operations cris_proc_profile_operations = {
+ .read = read_cris_profile,
+ .write = write_cris_profile,
+};
+
+static int
+__init init_cris_profile(void)
+{
+ struct proc_dir_entry *entry;
+ sample_buffer = (char*)kmalloc(SAMPLE_BUFFER_SIZE, GFP_KERNEL);
+ sample_buffer_pos = sample_buffer;
+ entry = create_proc_entry("system_profile", S_IWUSR | S_IRUGO, NULL);
+ if (entry) {
+ entry->proc_fops = &cris_proc_profile_operations;
+ entry->size = SAMPLE_BUFFER_SIZE;
+ }
+ prof_running = 1;
+ return 0;
+}
+
+__initcall(init_cris_profile);