From mboxrd@z Thu Jan 1 00:00:00 1970 From: Joe Perches Subject: Re: [PATCH] printk: Warn about dropped messages also on extended consoles Date: Thu, 30 Jul 2015 05:10:46 -0700 Message-ID: <1438258246.2677.17.camel@perches.com> References: <1438255732-31326-1-git-send-email-pmladek@suse.com> Mime-Version: 1.0 Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7bit Cc: akpm@linux-foundation.org, Tejun Heo , davem@davemloft.net, linux-kernel@vger.kernel.org, netdev@vger.kernel.org To: Petr Mladek Return-path: In-Reply-To: <1438255732-31326-1-git-send-email-pmladek@suse.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On Thu, 2015-07-30 at 13:28 +0200, Petr Mladek wrote: > The commit #6fe29354befe4c ("printk: implement support for extended console > drivers") added an extra buffer to format messages for extended consoles. > We need to put there also the warning about dropped messages, so it appears > on these consoles. [] > diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c [] > @@ -2254,8 +2254,15 @@ again: > } > > if (console_seq < log_first_seq) { > - len = sprintf(text, "** %u printk messages dropped ** ", > - (unsigned)(log_first_seq - console_seq)); > + static const char dropped_msg[] = > + "** %u printk messages dropped ** "; I don't see any value in dropped_msg as a const char array instead of just using it directly as a format in sprintf. The linker will still use a single format string in any case. memcpy might be faster. if (nr_ext_console_drivers) memcpy(ext_text, text, len + 1); > + unsigned int dropped_count = > + (unsigned int)(log_first_seq - console_seq); > + > + len = sprintf(text, dropped_msg, dropped_count); > + if (nr_ext_console_drivers) > + ext_len = sprintf(ext_text, dropped_msg, > + dropped_count); >