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Tue, 09 Oct 2018 05:32:06 -0700 (PDT) From: Sergey Senozhatsky X-Google-Original-From: Sergey Senozhatsky Date: Tue, 9 Oct 2018 21:31:51 +0900 To: Petr Mladek Cc: Sergey Senozhatsky , Steven Rostedt , Andrew Morton , Dmitriy Vyukov , Tetsuo Handa , Tejun Heo , Peter Zijlstra , LKML , Sergey Senozhatsky Subject: Re: [RFC][PATCH 3/3] printk: do not preliminary split up cont buffer Message-ID: <20181009123151.GA471@tigerII.localdomain> References: <20181002023836.4487-1-sergey.senozhatsky@gmail.com> <20181002023836.4487-4-sergey.senozhatsky@gmail.com> <20181009084241.tlmsjxnyxf4zx2fh@pathway.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20181009084241.tlmsjxnyxf4zx2fh@pathway.suse.cz> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On (10/09/18 10:42), Petr Mladek wrote: > On Tue 2018-10-02 11:38:36, Sergey Senozhatsky wrote: > > 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. > > > > Signed-off-by: Sergey Senozhatsky > > I wonder if this check ever triggered ;-) It is a nice clean up: > > Reviewed-by: Petr Mladek Thanks. -ss