1 files changed, 71 insertions, 15 deletions

diff --git a/fs/proc/base.c b/fs/proc/base.c
index 58c3e6a8e15e..a891fe4cb43b 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -2376,29 +2376,82 @@ static int proc_base_fill_cache(struct file *filp, void *dirent,
 }
 
 #ifdef CONFIG_TASK_IO_ACCOUNTING
-static int proc_pid_io_accounting(struct task_struct *task, char *buffer)
-{
+static int do_io_accounting(struct task_struct *task, char *buffer, int whole)
+{
+        u64 rchar, wchar, syscr, syscw;
+        struct task_io_accounting ioac;
+
+        if (!whole) {
+                rchar = task->rchar;
+                wchar = task->wchar;
+                syscr = task->syscr;
+                syscw = task->syscw;
+                memcpy(&ioac, &task->ioac, sizeof(ioac));
+        } else {
+                unsigned long flags;
+                struct task_struct *t = task;
+                rchar = wchar = syscr = syscw = 0;
+                memset(&ioac, 0, sizeof(ioac));
+
+                rcu_read_lock();
+                do {
+                        rchar += t->rchar;
+                        wchar += t->wchar;
+                        syscr += t->syscr;
+                        syscw += t->syscw;
+
+                        ioac.read_bytes += t->ioac.read_bytes;
+                        ioac.write_bytes += t->ioac.write_bytes;
+                        ioac.cancelled_write_bytes +=
+                                        t->ioac.cancelled_write_bytes;
+                        t = next_thread(t);
+                } while (t != task);
+                rcu_read_unlock();
+
+                if (lock_task_sighand(task, &flags)) {
+                        struct signal_struct *sig = task->signal;
+
+                        rchar += sig->rchar;
+                        wchar += sig->wchar;
+                        syscr += sig->syscr;
+                        syscw += sig->syscw;
+
+                        ioac.read_bytes += sig->ioac.read_bytes;
+                        ioac.write_bytes += sig->ioac.write_bytes;
+                        ioac.cancelled_write_bytes +=
+                                        sig->ioac.cancelled_write_bytes;
+
+                        unlock_task_sighand(task, &flags);
+                }
+        }
+
         return sprintf(buffer,
-#ifdef CONFIG_TASK_XACCT
                         "rchar: %llu\n"
                         "wchar: %llu\n"
                         "syscr: %llu\n"
                         "syscw: %llu\n"
-#endif
                         "read_bytes: %llu\n"
                         "write_bytes: %llu\n"
                         "cancelled_write_bytes: %llu\n",
-#ifdef CONFIG_TASK_XACCT
-                        (unsigned long long)task->rchar,
-                        (unsigned long long)task->wchar,
-                        (unsigned long long)task->syscr,
-                        (unsigned long long)task->syscw,
-#endif
-                        (unsigned long long)task->ioac.read_bytes,
-                        (unsigned long long)task->ioac.write_bytes,
-                        (unsigned long long)task->ioac.cancelled_write_bytes);
+                        (unsigned long long)rchar,
+                        (unsigned long long)wchar,
+                        (unsigned long long)syscr,
+                        (unsigned long long)syscw,
+                        (unsigned long long)ioac.read_bytes,
+                        (unsigned long long)ioac.write_bytes,
+                        (unsigned long long)ioac.cancelled_write_bytes);
+}
+
+static int proc_tid_io_accounting(struct task_struct *task, char *buffer)
+{
+        return do_io_accounting(task, buffer, 0);
 }
-#endif
+
+static int proc_tgid_io_accounting(struct task_struct *task, char *buffer)
+{
+        return do_io_accounting(task, buffer, 1);
+}
+#endif /* CONFIG_TASK_IO_ACCOUNTING */
 
 /*
  * Thread groups
@@ -2470,7 +2523,7 @@ static const struct pid_entry tgid_base_stuff[] = {
         REG("coredump_filter", S_IRUGO|S_IWUSR, coredump_filter),
 #endif
 #ifdef CONFIG_TASK_IO_ACCOUNTING
-        INF("io",       S_IRUGO, pid_io_accounting),
+        INF("io",       S_IRUGO, tgid_io_accounting),
 #endif
 };
 
@@ -2797,6 +2850,9 @@ static const struct pid_entry tid_base_stuff[] = {
 #ifdef CONFIG_FAULT_INJECTION
         REG("make-it-fail", S_IRUGO|S_IWUSR, fault_inject),
 #endif
+#ifdef CONFIG_TASK_IO_ACCOUNTING
+        INF("io",       S_IRUGO, tid_io_accounting),
+#endif
 };
 
 static int proc_tid_base_readdir(struct file * filp,