busybox/examples/mdev_fat.conf
Denys Vlasenko 5bce135e36 mdev: improve $SEQ handling; improve debug logging
Sequential run of concurrent mdev's was too simplistic:
they waited for /dev/mdev.seq to match. This could sometimes
cause cumulative loss of time on the order of a second.

Added SIGCHLD signaling from exiting mdev to all other mdev's.
Added debugging required to see that code actually works as intended.

Example of /dev/mdev.log (with "woken up" elevated from dbg lvl 3 to 2):

mdev[1023]: first seq written
     ^^^^ seq, not pid
mdev[1023]: 35.022395 ACTION:add SUBSYSTEM:module DEVNAME:(null) DEVPATH:/module/lib80211
mdev[1023]: rule matched, line -1
                          ^^^^^^^ means "default rule"
mdev[1023]: 35.022676 exiting
            ^^^^^^^^^ second,usec timestamp
mdev[1024]: 35.069691 ACTION:add SUBSYSTEM:vc DEVNAME:vcs9 DEVPATH:/devices/virtual/vc/vcs9
mdev[1024]: dev 7,9
mdev[1025]: 35.069889 waiting for '1024'
mdev[1026]: 35.069946 waiting for '1024'
mdev[1027]: 35.070151 waiting for '1024'
mdev[1024]: rule matched, line -1
mdev[1024]: mknod vcs9 (7,9) 20660 0:0
mdev[1024]: 35.070346 exiting
mdev[1025]: woken up
mdev[1026]: woken up
mdev[1025]: 35.071213 ACTION:add SUBSYSTEM:vc DEVNAME:vcsa9 DEVPATH:/devices/virtual/vc/vcsa9
            ^^^^^^^^^ took only a millisecond to start running after prev mdev exited
mdev[1025]: dev 7,137
mdev[1027]: woken up
mdev[1025]: rule matched, line -1
mdev[1025]: mknod vcsa9 (7,137) 20660 0:0
mdev[1025]: 35.072109 exiting

function                                             old     new   delta
mdev_main                                            849    1372    +523
curtime                                                -      59     +59
dirAction                                             87     134     +47
static.ts                                              -       8      +8
keywords                                              19      12      -7
make_device                                         2189    2119     -70

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2013-02-27 10:51:41 +01:00

115 lines
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#
# This is a sample mdev.conf
#
# Provide user, group, and mode information for devices. If a regex matches
# the device name provided by sysfs, use the appropriate user:group and mode
# instead of the default 0:0 660.
#
# Syntax:
# [-][ENVVAR=regex;]...devicename_regex user:group mode [=path]|[>path]|[!] [@|$|*cmd args...]
# [-][ENVVAR=regex;]...@maj,min[-min2] user:group mode [=path]|[>path]|[!] [@|$|*cmd args...]
# [-]$ENVVAR=regex user:group mode [=path]|[>path]|[!] [@|$|*cmd args...]
#
# [-]: do not stop on this match, continue reading mdev.conf
# =: move, >: move and create a symlink
# !: do not create device node
# @|$|*: run cmd if $ACTION=remove, @cmd if $ACTION=add, *cmd in all cases
# support module loading on hotplug
$MODALIAS=.* root:root 660 @modprobe "$MODALIAS"
# null may already exist; therefore ownership has to be changed with command
null root:root 666 @chmod 666 $MDEV
zero root:root 666
full root:root 666
random root:root 444
urandom root:root 444
hwrandom root:root 444
grsec root:root 660
kmem root:root 640
mem root:root 640
port root:root 640
# console may already exist; therefore ownership has to be changed with command
console root:tty 600 @chmod 600 $MDEV
ptmx root:tty 666
pty.* root:tty 660
# Typical devices
tty root:tty 666
tty[0-9]* root:tty 660
vcsa*[0-9]* root:tty 660
ttyS[0-9]* root:uucp 660
# block devices
ram([0-9]*) root:disk 660 >rd/%1
loop([0-9]+) root:disk 660 >loop/%1
sd[a-z].* root:disk 660 */lib/mdev/usbdisk_link
hd[a-z][0-9]* root:disk 660 */lib/mdev/ide_links
md[0-9]* root:disk 660
sr[0-9]* root:cdrom 660 @ln -sf $MDEV cdrom
fd[0-9]* root:floppy 660
# net devices
SUBSYSTEM=net;.* root:root 600 @nameif
tun[0-9]* root:root 600 =net/
tap[0-9]* root:root 600 =net/
# alsa sound devices and audio stuff
pcm.* root:audio 660 =snd/
control.* root:audio 660 =snd/
midi.* root:audio 660 =snd/
seq root:audio 660 =snd/
timer root:audio 660 =snd/
adsp root:audio 660 >sound/
audio root:audio 660 >sound/
dsp root:audio 660 >sound/
mixer root:audio 660 >sound/
sequencer.* root:audio 660 >sound/
# Less typical devices
# raid controllers
cciss!(.*) root:disk 660 =cciss/%1
ida!(.*) root:disk 660 =ida/%1
rd!(.*) root:disk 660 =rd/%1
ttyLTM[0-9] root:dialout 660 @ln -sf $MDEV modem
ttySHSF[0-9] root:dialout 660 @ln -sf $MDEV modem
slamr root:dialout 660 @ln -sf $MDEV slamr0
slusb root:dialout 660 @ln -sf $MDEV slusb0
fuse root:root 666
# dri device
card[0-9] root:video 660 =dri/
# misc stuff
agpgart root:root 660 >misc/
psaux root:root 660 >misc/
rtc root:root 664 >misc/
# input stuff
event[0-9]+ root:root 640 =input/
mice root:root 640 =input/
mouse[0-9] root:root 640 =input/
ts[0-9] root:root 600 =input/
# v4l stuff
vbi[0-9] root:video 660 >v4l/
video[0-9] root:video 660 >v4l/
# dvb stuff
dvb.* root:video 660 */lib/mdev/dvbdev
# load drivers for usb devices
usbdev[0-9].[0-9] root:root 660 */lib/mdev/usbdev
usbdev[0-9].[0-9]_.* root:root 660
# zaptel devices
zap(.*) root:dialout 660 =zap/%1
dahdi!(.*) root:dialout 660 =dahdi/%1