task IO accounting: improve code readability
Put all i/o statistics in struct proc_io_accounting and use inline functions to
initialize and increment statistics, removing a lot of single variable
assignments.
This also reduces the kernel size as following (with CONFIG_TASK_XACCT=y and
CONFIG_TASK_IO_ACCOUNTING=y).
text data bss dec hex filename
11651 0 0 11651 2d83 kernel/exit.o.before
11619 0 0 11619 2d63 kernel/exit.o.after
10886 132 136 11154 2b92 kernel/fork.o.before
10758 132 136 11026 2b12 kernel/fork.o.after
3082029 807968 4818600 8708597 84e1f5 vmlinux.o.before
3081869 807968 4818600 8708437 84e155 vmlinux.o.after
Signed-off-by: Andrea Righi <righi.andrea@gmail.com>
Acked-by: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/kernel/tsacct.c b/kernel/tsacct.c
index 3da47cc..f9cd256 100644
--- a/kernel/tsacct.c
+++ b/kernel/tsacct.c
@@ -94,14 +94,14 @@
stats->hiwater_vm = mm->hiwater_vm * PAGE_SIZE / KB;
mmput(mm);
}
- stats->read_char = p->rchar;
- stats->write_char = p->wchar;
- stats->read_syscalls = p->syscr;
- stats->write_syscalls = p->syscw;
+ 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;
#ifdef CONFIG_TASK_IO_ACCOUNTING
- stats->read_bytes = p->ioac.read_bytes;
- stats->write_bytes = p->ioac.write_bytes;
- stats->cancelled_write_bytes = p->ioac.cancelled_write_bytes;
+ 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;
#else
stats->read_bytes = 0;
stats->write_bytes = 0;