diff options
Diffstat (limited to 'arch/cris/kernel/profile.c')
-rw-r--r-- | arch/cris/kernel/profile.c | 73 |
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); |