]> git.baikalelectronics.ru Git - kernel.git/commit
printk: tweak do_syslog() to match comments
authorAlex Elder <elder@linaro.org>
Wed, 6 Aug 2014 23:08:59 +0000 (16:08 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Thu, 7 Aug 2014 01:01:24 +0000 (18:01 -0700)
commitbc3b4af7ef9476a6b67794c9660f17684be17583
treef60eafec77791616da6b12fc1ceb2c2039a11640
parent7f397b5549df34fc293c0078a45882d2e801a40e
printk: tweak do_syslog() to match comments

In do_syslog() there's a path used by kmsg_poll() and kmsg_read() that
only needs to know whether there's any data available to read (and not
its size).  These callers only check for non-zero return.  As a
shortcut, do_syslog() returns the difference between what has been
logged and what has been "seen."

The comments say that the "count of records" should be returned but it's
not.  Instead it returns (log_next_idx - syslog_idx), which is a
difference between buffer offsets--and the result could be negative.

The behavior is the same (it'll be zero or not in the same cases), but
the count of records is more meaningful and it matches what the comments
say.  So change the code to return that.

Signed-off-by: Alex Elder <elder@linaro.org>
Cc: Petr Mladek <pmladek@suse.cz>
Cc: Jan Kara <jack@suse.cz>
Cc: Joe Perches <joe@perches.com>
Cc: John Stultz <john.stultz@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
kernel/printk/printk.c