[PATCH 3/5] printk: Split message size computation

From: Petr Mladek
Date: Thu Apr 10 2014 - 05:45:17 EST


We will want to recompute the message size when shrinking too long messages.
Let's put the code into separate function.

The side effect of setting "pad_len" is not nice but it is worth removing
the code duplication. Note that I will probably have one more usage for this
function when handling messages safe way in NMI context.

This patch does not change the existing behavior.

Signed-off-by: Petr Mladek <pmladek@xxxxxxx>
---
kernel/printk/printk.c | 16 +++++++++++++---
1 file changed, 13 insertions(+), 3 deletions(-)

diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c
index 5de686b6b9e1..7416dfad0a28 100644
--- a/kernel/printk/printk.c
+++ b/kernel/printk/printk.c
@@ -339,6 +339,18 @@ static int log_make_free_space(u32 msg_size)
return -ENOMEM;
}

+/* compute the message size including the padding bytes */
+static u32 msg_used_size(u16 text_len, u16 dict_len, u32 *pad_len)
+{
+ u32 size;
+
+ size = sizeof(struct printk_log) + text_len + dict_len;
+ *pad_len = (-size) & (LOG_ALIGN - 1);
+ size += *pad_len;
+
+ return size;
+}
+
/* insert record into the buffer, discard old ones, update heads */
static void log_store(int facility, int level,
enum log_flags flags, u64 ts_nsec,
@@ -349,9 +361,7 @@ static void log_store(int facility, int level,
u32 size, pad_len;

/* number of '\0' padding bytes to next message */
- size = sizeof(struct printk_log) + text_len + dict_len;
- pad_len = (-size) & (LOG_ALIGN - 1);
- size += pad_len;
+ size = msg_used_size(text_len, dict_len, &pad_len);

/* if message does not fit empty log buffer, ignore it */
if (log_make_free_space(size))
--
1.8.4

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