linux_dsm_epyc7002/kernel/printk
Sergey Senozhatsky 0e96a19c44 printk: do not preliminary split up cont buffer
We have a proper 'overflow' check which tells us that we need to
split up existing cont buffer in separate records:

	if (cont.len + len > sizeof(cont.buf))
		cont_flush();

At the same time we also have one extra flush: "if cont buffer is
80% full then split it up" in cont_add():

	if (cont.len > (sizeof(cont.buf) * 80) / 100)
		cont_flush();

This looks to be redundant, since the existing "overflow" check
should work just fine, so remove this 80% check and wait for either
a normal cont termination \n, for preliminary flush due to
possible buffer overflow or for preliminary flush due to cont race.

Link: http://lkml.kernel.org/r/20181002023836.4487-4-sergey.senozhatsky@gmail.com
To: Steven Rostedt <rostedt@goodmis.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Dmitriy Vyukov <dvyukov@google.com>
Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Cc: Tejun Heo <tj@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: LKML <linux-kernel@vger.kernel.org>
Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
2018-10-12 10:03:39 +02:00
..
braille.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
braille.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
console_cmdline.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
internal.h printk/nmi: Prevent deadlock when accessing the main log buffer in NMI 2018-07-09 14:10:40 +02:00
Makefile printk: introduce per-cpu safe_print seq buffer 2017-02-08 11:07:11 +01:00
printk_safe.c printk/tracing: Do not trace printk_nmi_enter() 2018-09-06 11:24:05 -04:00
printk.c printk: do not preliminary split up cont buffer 2018-10-12 10:03:39 +02:00