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