On (11/22/17 20:52), Fengguang Wu wrote: [..] > > well, I think that that "consoles_format=syslog" command line parameter > > will be enabled only by those who actually want to have it - Fengguang's > > build robot and kernelCI (+ may be more setups). so I'd probably assume > > there are low risks here. may be I'm wrong. > > Yes, since it needs explicit enabling, local parsers should stay > working. Unless we send dmesg to other developers, but then they > might also receive $(dmesg --raw) outputs and need to handle <%u> > prefixes, too. > > > I think it makes sense to have syslog's format "<%u>[timestamp] text\n" > > on serial consoles (time stamp when PRINTK_TIME set; <%u> when > > consoles_format=syslog set). > > Thanks. Since the 0day scripts can already parse that format (code > is listed below), we should quickly benefit from that feature when > it's mainlined.
okay... who's going to send the patch? kernelCI folks? I have some sort of a patch. added console_msg_format= with the only available option so far - "syslog". may be people would want to have boot time, etc. on their consoles. who knows. may be msg_format will be extended someday in the future or may be not, and we can do something like "console_format_syslog" (or any better name). Not-yet-signed-off-by: Sergey Senozhatsky <[email protected]> --- Documentation/admin-guide/kernel-parameters.txt | 11 +++++++++++ kernel/printk/printk.c | 21 ++++++++++++++++++++- 2 files changed, 31 insertions(+), 1 deletion(-) diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 62436bd5f34a..42113e5181b2 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -640,6 +640,17 @@ console=brl,ttyS0 For now, only VisioBraille is supported. + console_msg_format= + [KNL] Control message format + By default we print messages in "[time stamp] text\n" + format (time stamp may not be printed, depending on + CONFIG_PRINTK_TIME or `printk_time' param). + syslog + Switch to syslog format (similar to "dmesg --raw" or + reading from /proc/kmsg): "<%u>[time stamp] text\n" + IOW, each message is getting prepended with the + facility and loglevel prefix. + consoleblank= [KNL] The console blank (screen saver) timeout in seconds. A value of 0 disables the blank timer. Defaults to 0. diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c index 5d81206a572d..034f3ad85f5b 100644 --- a/kernel/printk/printk.c +++ b/kernel/printk/printk.c @@ -277,6 +277,13 @@ EXPORT_SYMBOL(console_set_on_cmdline); /* Flag: console code may call schedule() */ static int console_may_schedule; +enum con_msg_format { + MSG_FORMAT_DEFAULT = 1, + MSG_FORMAT_SYSLOG = 2, +}; + +static int console_msg_format = MSG_FORMAT_DEFAULT; + /* * The printk log buffer consists of a chain of concatenated variable * length records. Every record starts with a record header, containing @@ -1913,6 +1920,15 @@ static int __add_preferred_console(char *name, int idx, char *options, c->index = idx; return 0; } + +static int __init console_msg_format_setup(char *str) +{ + if (!strncmp(str, "syslog", 6)) + console_msg_format = MSG_FORMAT_SYSLOG; + return 1; +} +__setup("console_msg_format=", console_msg_format_setup); + /* * Set up a console. Called via do_early_param() in init/main.c * for each "console=" parameter in the boot command line. @@ -2215,7 +2231,10 @@ void console_unlock(void) goto skip; } - len += msg_print_text(msg, false, text + len, sizeof(text) - len); + len += msg_print_text(msg, + console_msg_format & MSG_FORMAT_SYSLOG, + text + len, + sizeof(text) - len); if (nr_ext_console_drivers) { ext_len = msg_print_ext_header(ext_text, sizeof(ext_text), -- 2.15.0
