task IO accounting: move all IO statistics in struct task_io_accounting

Simplify the code of include/linux/task_io_accounting.h.

It is also more reasonable to have all the task i/o-related statistics in a
single struct (task_io_accounting).

Signed-off-by: Andrea Righi <[e-mail]>
Signed-off-by: Oleg Nesterov <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>

fs/proc/base.c

···
 #ifdef CONFIG_TASK_IO_ACCOUNTING
 static int do_io_accounting(struct task_struct *task, char *buffer, int whole)
 {
-	struct proc_io_accounting acct = task->ioac;
+	struct task_io_accounting acct = task->ioac;
 	unsigned long flags;
 
 	if (whole && lock_task_sighand(task, &flags)) {
···
 			"read_bytes: %llu\n"
 			"write_bytes: %llu\n"
 			"cancelled_write_bytes: %llu\n",
-			acct.chr.rchar, acct.chr.wchar,
-			acct.chr.syscr, acct.chr.syscw,
-			acct.blk.read_bytes, acct.blk.write_bytes,
-			acct.blk.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)

include/linux/sched.h

···
 	unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw;
 	unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt;
 	unsigned long inblock, oublock, cinblock, coublock;
-	struct proc_io_accounting ioac;
+	struct task_io_accounting ioac;
 
 	/*
 	 * Cumulative ns of scheduled CPU time for dead threads in the
···
 
 	unsigned long ptrace_message;
 	siginfo_t *last_siginfo; /* For ptrace use.  */
-	struct proc_io_accounting ioac;
+	struct task_io_accounting ioac;
 #if defined(CONFIG_TASK_XACCT)
 	u64 acct_rss_mem1;	/* accumulated rss usage */
 	u64 acct_vm_mem1;	/* accumulated virtual memory usage */
···
 #ifdef CONFIG_TASK_XACCT
 static inline void add_rchar(struct task_struct *tsk, ssize_t amt)
 {
-	tsk->ioac.chr.rchar += amt;
+	tsk->ioac.rchar += amt;
 }
 
 static inline void add_wchar(struct task_struct *tsk, ssize_t amt)
 {
-	tsk->ioac.chr.wchar += amt;
+	tsk->ioac.wchar += amt;
 }
 
 static inline void inc_syscr(struct task_struct *tsk)
 {
-	tsk->ioac.chr.syscr++;
+	tsk->ioac.syscr++;
 }
 
 static inline void inc_syscw(struct task_struct *tsk)
 {
-	tsk->ioac.chr.syscw++;
+	tsk->ioac.syscw++;
 }
 #else
 static inline void add_rchar(struct task_struct *tsk, ssize_t amt)

include/linux/task_io_accounting.h

···
 /*
- * proc_io_accounting: a structure which is used for recording a single task's
+ * task_io_accounting: a structure which is used for recording a single task's
  * IO statistics.
  *
  * Don't include this header file directly - it is designed to be dragged in via
···
  * Blame [e-mail] for all this.
  */
 
+struct task_io_accounting {
 #ifdef CONFIG_TASK_XACCT
-struct task_chr_io_accounting {
 	/* bytes read */
 	u64 rchar;
 	/*  bytes written */
···
 	u64 syscr;
 	/* # of write syscalls */
 	u64 syscw;
-};
-#else /* CONFIG_TASK_XACCT */
-struct task_chr_io_accounting {
-};
 #endif /* CONFIG_TASK_XACCT */
 
 #ifdef CONFIG_TASK_IO_ACCOUNTING
-struct task_io_accounting {
 	/*
 	 * The number of bytes which this task has caused to be read from
 	 * storage.
···
 	 * information loss in doing that.
 	 */
 	u64 cancelled_write_bytes;
-};
-#else /* CONFIG_TASK_IO_ACCOUNTING */
-struct task_io_accounting {
-};
 #endif /* CONFIG_TASK_IO_ACCOUNTING */
-
-struct proc_io_accounting {
-	struct task_chr_io_accounting chr;
-	struct task_io_accounting blk;
 };

include/linux/task_io_accounting_ops.h

···
 #ifdef CONFIG_TASK_IO_ACCOUNTING
 static inline void task_io_account_read(size_t bytes)
 {
-	current->ioac.blk.read_bytes += bytes;
+	current->ioac.read_bytes += bytes;
 }
 
 /*
···
  */
 static inline unsigned long task_io_get_inblock(const struct task_struct *p)
 {
-	return p->ioac.blk.read_bytes >> 9;
+	return p->ioac.read_bytes >> 9;
 }
 
 static inline void task_io_account_write(size_t bytes)
 {
-	current->ioac.blk.write_bytes += bytes;
+	current->ioac.write_bytes += bytes;
 }
 
 /*
···
  */
 static inline unsigned long task_io_get_oublock(const struct task_struct *p)
 {
-	return p->ioac.blk.write_bytes >> 9;
+	return p->ioac.write_bytes >> 9;
 }
 
 static inline void task_io_account_cancelled_write(size_t bytes)
 {
-	current->ioac.blk.cancelled_write_bytes += bytes;
+	current->ioac.cancelled_write_bytes += bytes;
 }
 
-static inline void task_io_accounting_init(struct proc_io_accounting *ioac)
+static inline void task_io_accounting_init(struct task_io_accounting *ioac)
 {
 	memset(ioac, 0, sizeof(*ioac));
 }
 
-static inline void task_blk_io_accounting_add(struct proc_io_accounting *dst,
-						struct proc_io_accounting *src)
+static inline void task_blk_io_accounting_add(struct task_io_accounting *dst,
+						struct task_io_accounting *src)
 {
-	dst->blk.read_bytes += src->blk.read_bytes;
-	dst->blk.write_bytes += src->blk.write_bytes;
-	dst->blk.cancelled_write_bytes += src->blk.cancelled_write_bytes;
+	dst->read_bytes += src->read_bytes;
+	dst->write_bytes += src->write_bytes;
+	dst->cancelled_write_bytes += src->cancelled_write_bytes;
 }
 
 #else
···
 {
 }
 
-static inline void task_io_accounting_init(struct proc_io_accounting *ioac)
+static inline void task_io_accounting_init(struct task_io_accounting *ioac)
 {
 }
 
-static inline void task_blk_io_accounting_add(struct proc_io_accounting *dst,
-						struct proc_io_accounting *src)
+static inline void task_blk_io_accounting_add(struct task_io_accounting *dst,
+						struct task_io_accounting *src)
 {
 }
 
 #endif /* CONFIG_TASK_IO_ACCOUNTING */
 
 #ifdef CONFIG_TASK_XACCT
-static inline void task_chr_io_accounting_add(struct proc_io_accounting *dst,
-						struct proc_io_accounting *src)
+static inline void task_chr_io_accounting_add(struct task_io_accounting *dst,
+						struct task_io_accounting *src)
 {
-	dst->chr.rchar += src->chr.rchar;
-	dst->chr.wchar += src->chr.wchar;
-	dst->chr.syscr += src->chr.syscr;
-	dst->chr.syscw += src->chr.syscw;
+	dst->rchar += src->rchar;
+	dst->wchar += src->wchar;
+	dst->syscr += src->syscr;
+	dst->syscw += src->syscw;
 }
 #else
-static inline void task_chr_io_accounting_add(struct proc_io_accounting *dst,
-						struct proc_io_accounting *src)
+static inline void task_chr_io_accounting_add(struct task_io_accounting *dst,
+						struct task_io_accounting *src)
 {
 }
 #endif /* CONFIG_TASK_XACCT */
 
-static inline void task_io_accounting_add(struct proc_io_accounting *dst,
-						struct proc_io_accounting *src)
+static inline void task_io_accounting_add(struct task_io_accounting *dst,
+						struct task_io_accounting *src)
 {
 	task_chr_io_accounting_add(dst, src);
 	task_blk_io_accounting_add(dst, src);

kernel/tsacct.c

···
 		stats->hiwater_vm    = mm->hiwater_vm * PAGE_SIZE / KB;
 		mmput(mm);
 	}
-	stats->read_char	= p->ioac.chr.rchar;
-	stats->write_char	= p->ioac.chr.wchar;
-	stats->read_syscalls	= p->ioac.chr.syscr;
-	stats->write_syscalls	= p->ioac.chr.syscw;
+	stats->read_char	= p->ioac.rchar;
+	stats->write_char	= p->ioac.wchar;
+	stats->read_syscalls	= p->ioac.syscr;
+	stats->write_syscalls	= p->ioac.syscw;
 #ifdef CONFIG_TASK_IO_ACCOUNTING
-	stats->read_bytes	= p->ioac.blk.read_bytes;
-	stats->write_bytes	= p->ioac.blk.write_bytes;
-	stats->cancelled_write_bytes = p->ioac.blk.cancelled_write_bytes;
+	stats->read_bytes	= p->ioac.read_bytes;
+	stats->write_bytes	= p->ioac.write_bytes;
+	stats->cancelled_write_bytes = p->ioac.cancelled_write_bytes;
 #else
 	stats->read_bytes	= 0;
 	stats->write_bytes	= 0;