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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /arch/cris/kernel/profile.c
Initial import
Diffstat (limited to 'arch/cris/kernel/profile.c')
-rw-r--r--arch/cris/kernel/profile.c86
1 files changed, 86 insertions, 0 deletions
diff --git a/arch/cris/kernel/profile.c b/arch/cris/kernel/profile.c
new file mode 100644
index 000000000..cd9f15b92
--- /dev/null
+++ b/arch/cris/kernel/profile.c
@@ -0,0 +1,86 @@
+#include <linux/init.h>
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/proc_fs.h>
+#include <linux/slab.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;
+ ssize_t ret;
+
+ ret = simple_read_from_buffer(buf, count, ppos, sample_buffer,
+ SAMPLE_BUFFER_SIZE);
+ if (ret < 0)
+ return ret;
+
+ memset(sample_buffer + p, 0, ret);
+
+ return ret;
+}
+
+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);
+ return count < SAMPLE_BUFFER_SIZE ? count : SAMPLE_BUFFER_SIZE;
+}
+
+static const struct file_operations cris_proc_profile_operations = {
+ .read = read_cris_profile,
+ .write = write_cris_profile,
+ .llseek = default_llseek,
+};
+
+static int __init init_cris_profile(void)
+{
+ struct proc_dir_entry *entry;
+
+ sample_buffer = kmalloc(SAMPLE_BUFFER_SIZE, GFP_KERNEL);
+ if (!sample_buffer) {
+ return -ENOMEM;
+ }
+
+ sample_buffer_pos = sample_buffer;
+
+ entry = proc_create("system_profile", S_IWUSR | S_IRUGO, NULL,
+ &cris_proc_profile_operations);
+ if (entry) {
+ proc_set_size(entry, SAMPLE_BUFFER_SIZE);
+ }
+ prof_running = 1;
+
+ return 0;
+}
+__initcall(init_cris_profile);
+