Re: [RFC] Prepend timestamp in msgbuf

On Mon Oct 17 11, Arnaud Lacombe wrote:
> Hi,
> 
> On Mon, Oct 17, 2011 at 3:44 PM, Alexander Best <arundel_at_freebsd.org> wrote:
> > On Mon Oct 17 11, Arnaud Lacombe wrote:
> >> Hi,
> >>
> >> On Mon, Oct 17, 2011 at 2:01 PM, Alexander Best <arundel_at_freebsd.org> wrote:
> >> > On Fri Oct 14 11, Arnaud Lacombe wrote:
> >> >> Hi,
> >> >>
> >> >> On Fri, Oct 14, 2011 at 8:52 AM, Nali Toja <nalitoja_at_gmail.com> wrote:
> >> >> > Alexander Best <arundel_at_freebsd.org> writes:
> >> >> >
> >> >> >>> On Fri Oct 14 11, Poul-Henning Kamp wrote:
> >> >> >>> > In message <20111014085609.GA3799_at_freebsd.org>, Alexander Best writes:
> >> >> >>> >
> >> >> >>> > >1) would it be possible to prepend those timestamps to the actual console
> >> >> >>> > >output and not only to the output of demsg? maybe via a sysctl toggle?
> >> >> >>> >
> >> >> >>> > The kernel does not know enough about timezones to emit anything
> >> >> >>> > but UTC timestamps.
> >> >> >>>
> >> >> >>> hmm ok.
> >> >> >>>
> >> >> >>> >
> >> >> >>> > >2) my dmesg output contains a lot of these entries: "<118>"
> >> >> >>> >
> >> >> >>> > These are magic markers for syslogd(8) specifying priority.
> >> >> >>>
> >> >> >>> it would be nice, if their output could be turned off via a dmesg flag imo.
> >> >> >>>
> >> >> >>> >
> >> >> >>> > >3) roughly the first 30 lines of my dmesg output have the timestamp "[1.0]".
> >> >> >>> > >would it be possible to have more accuracy there?
> >> >> >>> >
> >> >> >>> > No, because we don't know the time until we've found the RTC chip.
> >> >> >>>
> >> >> >>> maybe prepending the output with [??] instead of [1.0] would make more sense,
> >> >> >>> so users knows that those timestamps are bogus.
> >> >> >>
> >> >> >> maybe the granularity of the timestamps could be limited to a static value? the
> >> >> >> following output doesn't really look pretty:
> >> >> >>
> >> >> >> [7.729516] <118>/dev/ufs/varfs: clean, 879143 free (7407 frags, 108967 blocks, 0.7% fragmentation)
> >> >> >> [7.891512] <118>Mounting local file systems:WARNING: TMPFS is considered to be a highly experimental feature in FreeBSD.
> >> >> >> [8.33519] .
> >> >> >> [9.440514] <118>Setting hostname: otaku.
> >> >> >> [9.744516] wlan0: Ethernet address: 00:0f:b5:82:07:c8
> >> >> >> [9.850516] <118>Starting wpa_supplicant.
> >> >> >> [10.335514] <118>Starting Network: lo0 ath0.
> >> >> >>
> >> >> >> so it would be nice, if trailing zeros got printed out, too.
> >> >> >
> >> >> > Why not make formatting similar to linux/xorg logs, e.g.
> >> >> >
> >> >> >  [    31.897] (**) Option "XkbLayout" "us"
> >> >> >  [    31.897] (II) XINPUT: Adding extended input device "<default keyboard>" (type: KEYBOARD, id 7)
> >> >> >  [ 11485.404] (II) 3rd Button detected: disabling emulate3Button
> >> >> >
> >> >> >  [    0.000000] Linux version 3.0-ARCH (tobias_at_T-POWA-LX) (gcc version 4.6.1 20110819 (prerelease) (GCC) ) #1 SMP PREEMPT Tue Aug 30 08:53:25 CEST 2011
> >> >> >  [    0.000000] Command line: root=/dev/disk/by-uuid/625db1f5-9b51-4d2d-acb7-6726f4d7e199 ro
> >> >> >  [...]
> >> >> >  [   15.096862] NET: Registered protocol family 10
> >> >> >  [   16.792594] [drm] nouveau 0000:01:00.0: plugged DVI-I-2
> >> >> >  [   26.054186] eth0: no IPv6 routers present
> >> >> >
> >> >> > A way to convert those timestamps to localtime or time delta[1] post-mortem
> >> >> > via dmesg(8) would be good, too.
> >> >> >
> >> >> well, I do not care for the "pretty" side of the thing, however, this
> >> >> is just a matter length modifier in the string format; should be
> >> >> trivial to fix.
> >> >
> >> > cc -c -O -pipe -march=core2 -std=c99 -g -Wall -Wredundant-decls -Wnested-externs -Wstrict-prototypes -Wmissing-prototypes -Wpointer-arith -Winline -Wcast-qual -Wundef -Wno-pointer-sign -Wmissing-include-dirs -nostdinc  -I. -I/usr/git-freebsd-head/sys -I/usr/git-freebsd-head/sys/contrib/altq -D_KERNEL -DHAVE_KERNEL_OPTION_HEADERS -include opt_global.h -fno-common -finline-limit=8000 --param inline-unit-growth=100 --param large-function-growth=1000  -fno-omit-frame-pointer -mno-sse -mcmodel=kernel -mno-red-zone -mno-mmx -msoft-float -fno-asynchronous-unwind-tables -ffreestanding -fformat-extensions -fdiagnostics-show-option -fstack-protector -Werror  /usr/git-freebsd-head/sys/kern/subr_msgbuf.c
> >> > cc1: warnings being treated as errors
> >> > /usr/git-freebsd-head/sys/kern/subr_msgbuf.c: In function 'msgbuf_do_addchar':
> >> > /usr/git-freebsd-head/sys/kern/subr_msgbuf.c:171: warning: format '%d' expects type 'int', but argument 4 has type 'time_t' [-Wformat]
> >> > *** Error code 1
> >> >
> >> > Stop in /usr/obj/usr/git-freebsd-head/sys/ARUNDEL.
> >> > *** Error code 1
> >> >
> >> > Stop in /usr/git-freebsd-head.
> >> > *** Error code 1
> >> >
> >> > Stop in /usr/git-freebsd-head.
> >> >
> >> FreeBSD has no time_t PRI... macros in any <machine/_inttypes.h>,
> >> eventually cast it to `long'.
> >
> > just wanted to tell you that your patch causes buildkernel to fail on certain
> > archs (amd64 in my case) and that it appears you didn't run
> > 'make universe-kernels' to check, whether your patch breaks anything.
> >
> > i'll leave the details to you.
> I have no interest testing architectures/kernels I have no interest
> in. Of course, this statement only apply as long as I have no full
> control over the future of the feature.

sorry i was under the impression that this feature was a candidate to make it
into HEAD.

> 
>  - Arnaud