[PATCH 3/5] printk: stop actually recording LOG_PREFIX

From: Alex Elder
Date: Thu Jul 17 2014 - 13:59:26 EST


Whenever log_store() sees a LOG_PREFIX flag it marks the previous
log entry (if there is one) with LOG_NEWLINE, which (also) produces
the desired effect.

There's therefore no need to record LOG_PREFIX in log records.

If no log entries contain LOG_PREFIX, devkmsg_read() and
msg_print_text() don't need to check for it.

Signed-off-by: Alex Elder <elder@xxxxxxxxxx>
---
kernel/printk/printk.c | 11 +++++++----
1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c
index 6b72a77..df38b5e 100644
--- a/kernel/printk/printk.c
+++ b/kernel/printk/printk.c
@@ -432,8 +432,11 @@ static int log_store(int facility, int level,
* If we're forcing a new log record, update the flags for
* the previous one to mark it complete.
*/
- if (flags & LOG_PREFIX && log_last_msg)
- log_last_msg->flags |= LOG_NEWLINE;
+ if (flags & LOG_PREFIX) {
+ if (log_last_msg)
+ log_last_msg->flags |= LOG_NEWLINE;
+ flags &= ~LOG_PREFIX;
+ }

msg = (struct printk_log *)(log_buf + log_next_idx);
memcpy(log_text(msg), text, text_len);
@@ -633,7 +636,7 @@ static ssize_t devkmsg_read(struct file *file, char __user *buf,
* a record that should be merged with one or more earlier records.
* And a '-' indicates a "normal" self-contained single record.
*/
- if (!(user->prev & LOG_NEWLINE) && !(msg->flags & LOG_PREFIX))
+ if (!(user->prev & LOG_NEWLINE))
cont = '+';
else if (!(msg->flags & LOG_NEWLINE))
cont = 'c';
@@ -1020,7 +1023,7 @@ static size_t msg_print_text(const struct printk_log *msg, enum log_flags prev,
bool newline = true;
size_t len = 0;

- if (!(prev & LOG_NEWLINE) && !(msg->flags & LOG_PREFIX))
+ if (!(prev & LOG_NEWLINE))
prefix = false;

if (!(msg->flags & LOG_NEWLINE))
--
1.9.1

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/