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Subject[PATCH v2,RESEND] doc: zh_CN: fix style problems for io_ordering.txt
Date
Problems exist in the Chinese translation of io_ordering.txt.
Partly for the difference between Chinese and English character
encoding format, and the others are of the failure to comply
with the ReST markups.

Signed-off-by: Wang Wenhu <wenhu.wang@vivo.com>
---
v2: resend for the failure of delivering.

.../translations/zh_CN/io_ordering.txt | 72 ++++++++++++-------
1 file changed, 46 insertions(+), 26 deletions(-)

diff --git a/Documentation/translations/zh_CN/io_ordering.txt b/Documentation/translations/zh_CN/io_ordering.txt
index 1f8127bdd415..080ed2911db0 100644
--- a/Documentation/translations/zh_CN/io_ordering.txt
+++ b/Documentation/translations/zh_CN/io_ordering.txt
@@ -29,39 +29,59 @@ Documentation/io_ordering.txt 的中文翻译
这也可以保证后面的写操作只在前面的写操作之后到达设备(这非常类似于内存
屏障操作,mb(),不过仅适用于I/O)。

+A more concrete example from a hypothetical device driver::
+
+ ...
+ CPU A: spin_lock_irqsave(&dev_lock, flags)
+ CPU A: val = readl(my_status);
+ CPU A: ...
+ CPU A: writel(newval, ring_ptr);
+ CPU A: spin_unlock_irqrestore(&dev_lock, flags)
+ ...
+ CPU B: spin_lock_irqsave(&dev_lock, flags)
+ CPU B: val = readl(my_status);
+ CPU B: ...
+ CPU B: writel(newval2, ring_ptr);
+ CPU B: spin_unlock_irqrestore(&dev_lock, flags)
+ ...
+
+
假设一个设备驱动程的具体例子:
+::

+ ...
+ CPU A: spin_lock_irqsave(&dev_lock, flags)
+ CPU A: val = readl(my_status);
+ CPU A: ...
+ CPU A: writel(newval, ring_ptr);
+ CPU A: spin_unlock_irqrestore(&dev_lock, flags)
+ ...
+ CPU B: spin_lock_irqsave(&dev_lock, flags)
+ CPU B: val = readl(my_status);
+ CPU B: ...
+ CPU B: writel(newval2, ring_ptr);
+ CPU B: spin_unlock_irqrestore(&dev_lock, flags)
...
-CPU A: spin_lock_irqsave(&dev_lock, flags)
-CPU A: val = readl(my_status);
-CPU A: ...
-CPU A: writel(newval, ring_ptr);
-CPU A: spin_unlock_irqrestore(&dev_lock, flags)
- ...
-CPU B: spin_lock_irqsave(&dev_lock, flags)
-CPU B: val = readl(my_status);
-CPU B: ...
-CPU B: writel(newval2, ring_ptr);
-CPU B: spin_unlock_irqrestore(&dev_lock, flags)
- ...
+

上述例子中,设备可能会先接收到newval2的值,然后接收到newval的值,问题就
发生了。不过很容易通过下面方法来修复:
+::

- ...
-CPU A: spin_lock_irqsave(&dev_lock, flags)
-CPU A: val = readl(my_status);
-CPU A: ...
-CPU A: writel(newval, ring_ptr);
-CPU A: (void)readl(safe_register); /* 配置寄存器?*/
-CPU A: spin_unlock_irqrestore(&dev_lock, flags)
- ...
-CPU B: spin_lock_irqsave(&dev_lock, flags)
-CPU B: val = readl(my_status);
-CPU B: ...
-CPU B: writel(newval2, ring_ptr);
-CPU B: (void)readl(safe_register); /* 配置寄存器?*/
-CPU B: spin_unlock_irqrestore(&dev_lock, flags)
+ ...
+ CPU A: spin_lock_irqsave(&dev_lock, flags)
+ CPU A: val = readl(my_status);
+ CPU A: ...
+ CPU A: writel(newval, ring_ptr);
+ CPU A: (void)readl(safe_register); /* 配置寄存器?*/
+ CPU A: spin_unlock_irqrestore(&dev_lock, flags)
+ ...
+ CPU B: spin_lock_irqsave(&dev_lock, flags)
+ CPU B: val = readl(my_status);
+ CPU B: ...
+ CPU B: writel(newval2, ring_ptr);
+ CPU B: (void)readl(safe_register); /* 配置寄存器?*/
+ CPU B: spin_unlock_irqrestore(&dev_lock, flags)

在解决方案中,读取safe_register寄存器,触发IO芯片清刷未处理的写操作,
再处理后面的读操作,防止引发数据不一致问题。
--
2.17.1
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