1 files changed, 14 insertions, 52 deletions

diff --git a/fs/proc/base.c b/fs/proc/base.c
index 81bce6791bfc..01ed610f9b87 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -53,6 +53,7 @@
 #include <linux/time.h>
 #include <linux/proc_fs.h>
 #include <linux/stat.h>
+#include <linux/task_io_accounting_ops.h>
 #include <linux/init.h>
 #include <linux/capability.h>
 #include <linux/file.h>
@@ -1859,8 +1860,7 @@ static const struct file_operations proc_fd_operations = {
  * /proc/pid/fd needs a special permission handler so that a process can still
  * access /proc/self/fd after it has executed a setuid().
  */
-static int proc_fd_permission(struct inode *inode, int mask,
-				struct nameidata *nd)
+static int proc_fd_permission(struct inode *inode, int mask)
 {
 	int rv;
 
@@ -2403,53 +2403,18 @@ static int proc_base_fill_cache(struct file *filp, void *dirent,
 #ifdef CONFIG_TASK_IO_ACCOUNTING
 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;
+	struct task_io_accounting acct = task->ioac;
+	unsigned long flags;
 
-			rchar += sig->rchar;
-			wchar += sig->wchar;
-			syscr += sig->syscr;
-			syscw += sig->syscw;
+	if (whole && lock_task_sighand(task, &flags)) {
+		struct task_struct *t = task;
 
-			ioac.read_bytes += sig->ioac.read_bytes;
-			ioac.write_bytes += sig->ioac.write_bytes;
-			ioac.cancelled_write_bytes +=
-					sig->ioac.cancelled_write_bytes;
+		task_io_accounting_add(&acct, &task->signal->ioac);
+		while_each_thread(task, t)
+			task_io_accounting_add(&acct, &t->ioac);
 
-			unlock_task_sighand(task, &flags);
-		}
+		unlock_task_sighand(task, &flags);
 	}
-
 	return sprintf(buffer,
 			"rchar: %llu\n"
 			"wchar: %llu\n"
@@ -2458,13 +2423,10 @@ static int do_io_accounting(struct task_struct *task, char *buffer, int whole)
 			"read_bytes: %llu\n"
 			"write_bytes: %llu\n"
 			"cancelled_write_bytes: %llu\n",
-			(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);
+			acct.rchar, acct.wchar,
+			acct.syscr, acct.syscw,
+			acct.read_bytes, acct.write_bytes,
+			acct.cancelled_write_bytes);
 }
 
 static int proc_tid_io_accounting(struct task_struct *task, char *buffer)