xref: /OK3568_Linux_fs/kernel/include/linux/task_io_accounting.h (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun /* SPDX-License-Identifier: GPL-2.0 */
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun  * task_io_accounting: a structure which is used for recording a single task's
4*4882a593Smuzhiyun  * IO statistics.
5*4882a593Smuzhiyun  *
6*4882a593Smuzhiyun  * Don't include this header file directly - it is designed to be dragged in via
7*4882a593Smuzhiyun  * sched.h.
8*4882a593Smuzhiyun  *
9*4882a593Smuzhiyun  * Blame Andrew Morton for all this.
10*4882a593Smuzhiyun  */
11*4882a593Smuzhiyun 
12*4882a593Smuzhiyun struct task_io_accounting {
13*4882a593Smuzhiyun #ifdef CONFIG_TASK_XACCT
14*4882a593Smuzhiyun 	/* bytes read */
15*4882a593Smuzhiyun 	u64 rchar;
16*4882a593Smuzhiyun 	/*  bytes written */
17*4882a593Smuzhiyun 	u64 wchar;
18*4882a593Smuzhiyun 	/* # of read syscalls */
19*4882a593Smuzhiyun 	u64 syscr;
20*4882a593Smuzhiyun 	/* # of write syscalls */
21*4882a593Smuzhiyun 	u64 syscw;
22*4882a593Smuzhiyun 	/* # of fsync syscalls */
23*4882a593Smuzhiyun 	u64 syscfs;
24*4882a593Smuzhiyun #endif /* CONFIG_TASK_XACCT */
25*4882a593Smuzhiyun 
26*4882a593Smuzhiyun #ifdef CONFIG_TASK_IO_ACCOUNTING
27*4882a593Smuzhiyun 	/*
28*4882a593Smuzhiyun 	 * The number of bytes which this task has caused to be read from
29*4882a593Smuzhiyun 	 * storage.
30*4882a593Smuzhiyun 	 */
31*4882a593Smuzhiyun 	u64 read_bytes;
32*4882a593Smuzhiyun 
33*4882a593Smuzhiyun 	/*
34*4882a593Smuzhiyun 	 * The number of bytes which this task has caused, or shall cause to be
35*4882a593Smuzhiyun 	 * written to disk.
36*4882a593Smuzhiyun 	 */
37*4882a593Smuzhiyun 	u64 write_bytes;
38*4882a593Smuzhiyun 
39*4882a593Smuzhiyun 	/*
40*4882a593Smuzhiyun 	 * A task can cause "negative" IO too.  If this task truncates some
41*4882a593Smuzhiyun 	 * dirty pagecache, some IO which another task has been accounted for
42*4882a593Smuzhiyun 	 * (in its write_bytes) will not be happening.  We _could_ just
43*4882a593Smuzhiyun 	 * subtract that from the truncating task's write_bytes, but there is
44*4882a593Smuzhiyun 	 * information loss in doing that.
45*4882a593Smuzhiyun 	 */
46*4882a593Smuzhiyun 	u64 cancelled_write_bytes;
47*4882a593Smuzhiyun #endif /* CONFIG_TASK_IO_ACCOUNTING */
48*4882a593Smuzhiyun };
49