android_kernel_samsung_msm8976/Documentation
Mel Gorman db9e5679d6 delay-accounting: reimplement -c for getdelays.c to report information on a target command
Task delay-accounting was identified as one means of determining how long
a process spends in congestion_wait() without adding new statistics.  For
example, if the workload should not be doing IO, delay-accounting could
reveal how long it was spending in unexpected IO or delays.
Unfortunately, on closer examination it was clear that getdelays does not
act as documented.

Commit a3baf649 ("per-task-delay-accounting: documentation") added
Documentation/accounting/getdelays.c with a -c switch that was documented
to fork/exec a child and report statistics on it but for reasons that are
unclear to me, commit 9e06d3f9 deleted support for this switch but did not
update the documentation.  It might be an oversight or it might be because
the control flow of the program meant that accounting information would be
printed once early in the lifetime of the program making it of limited
use.

This patch reimplements -c for getdelays.c to act as documented.  Unlike
the original version, it waits until the command completes before printing
any information on it.  An example of it being used looks like

$ ./getdelays -d -c find /home/mel -name mel
print delayacct stats ON
/home/mel
/home/mel/.notes-wine/drive_c/windows/profiles/mel
/home/mel/.wine/drive_c/windows/profiles/mel
/home/mel/git-configs/dot.kde/share/apps/konqueror/home/mel
PID	5923

CPU             count     real total  virtual total    delay total
                42779     5051232096     5164722692      564207988
IO              count    delay total
                41727    97804147758
SWAP            count    delay total
                    0              0
RECLAIM         count    delay total
                    0              0

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Acked-by: Balbir Singh <balbir@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-10-27 18:03:17 -07:00
..
ABI Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mjg59/platform-drivers-x86 2010-10-25 08:28:13 -07:00
accounting delay-accounting: reimplement -c for getdelays.c to report information on a target command 2010-10-27 18:03:17 -07:00
acpi
aoe
arm Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2010-10-24 13:41:39 -07:00
auxdisplay
blackfin
block
blockdev
cdrom
cgroups cgroup: add clone_children control file 2010-10-27 18:03:09 -07:00
connector
console
cpu-freq
cpuidle
cris
crypto
development-process
device-mapper
DocBook docbook: add idr/ida to kernel-api docbook 2010-10-26 17:40:56 -07:00
driver-model
dvb
early-userspace
fault-injection
fb
filesystems /proc/pid/pagemap: document in Documentation/filesystems/proc.txt 2010-10-27 18:03:13 -07:00
firmware_class
frv
hwmon hwmon: LTC4261 Hardware monitoring driver 2010-10-25 14:11:20 -07:00
i2c
i2o
ia64
ide
infiniband
input
ioctl
isdn
ja_JP
kbuild
kdump
ko_KR
kvm KVM: Document that KVM_GET_SUPPORTED_CPUID may return emulated values 2010-10-24 10:52:48 +02:00
laptops
lguest
m68k
make
mips
misc-devices Documentation: short descriptions for bh1770glc and apds990x drivers 2010-10-26 16:52:14 -07:00
mmc
mn10300
mtd
namespaces
netlabel
networking
parisc
PCI
pcmcia
power
powerpc Merge git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb-2.6 2010-10-22 20:30:48 -07:00
pps
prctl
RCU
s390
scheduler
scsi
serial
sh
sound Merge branch 'topic/hda' into for-linus 2010-10-25 10:40:05 +02:00
sparc
spi
sysctl doc: clarify the behaviour of dirty_ratio/dirty_bytes 2010-10-27 18:03:08 -07:00
telephony
thermal
timers Documentation/timers/hpet_example.c: add supporting info for hpet_example 2010-10-26 16:52:11 -07:00
trace tracing, vmscan: add trace events for LRU list shrinking 2010-10-26 16:52:07 -07:00
uml
usb USB: teach "devices" file about Wireless and SuperSpeed USB 2010-10-22 10:21:40 -07:00
video4linux
vm mm: highmem documentation 2010-10-26 16:52:08 -07:00
w1
watchdog
wimax
x86 Merge branch 'x86-irq-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip 2010-10-22 08:54:21 -07:00
zh_CN
.gitignore
00-INDEX
apparmor.txt
applying-patches.txt
atomic_ops.txt
bad_memory.txt
basic_profiling.txt
binfmt_misc.txt
braille-console.txt
bt8xxgpio.txt
btmrvl.txt
BUG-HUNTING
bus-virt-phys-mapping.txt
cachetlb.txt
Changes
circular-buffers.txt
coccinelle.txt
CodingStyle
cpu-hotplug.txt
cpu-load.txt
cputopology.txt
credentials.txt
dcdbas.txt
debugging-modules.txt
debugging-via-ohci1394.txt
dell_rbu.txt
devices.txt Merge git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb-2.6 2010-10-22 20:30:48 -07:00
DMA-API-HOWTO.txt
DMA-API.txt
DMA-attributes.txt
DMA-ISA-LPC.txt
dmaengine.txt
dontdiff
dynamic-debug-howto.txt Dynamic Debug: Introduce ddebug_query= boot parameter 2010-10-22 10:16:42 -07:00
edac.txt
eisa.txt
email-clients.txt
feature-removal-schedule.txt cgroup: notify ns_cgroup deprecated 2010-10-27 18:03:09 -07:00
flexible-arrays.txt
futex-requeue-pi.txt
gcov.txt
gpio.txt
highuid.txt
HOWTO
hw_random.txt
init.txt
initrd.txt
Intel-IOMMU.txt
intel_txt.txt
io-mapping.txt
io_ordering.txt
iostats.txt
IPMI.txt
IRQ-affinity.txt
IRQ.txt
irqflags-tracing.txt
isapnp.txt
java.txt
kernel-doc-nano-HOWTO.txt
kernel-docs.txt
kernel-parameters.txt Merge branch 'nfs-for-2.6.37' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6 2010-10-25 13:48:29 -07:00
keys-request-key.txt
keys.txt
kmemcheck.txt
kmemleak.txt
kobject.txt
kprobes.txt
kref.txt
ldm.txt
leds-class.txt
leds-lp3944.txt
local_ops.txt
lockdep-design.txt
lockstat.txt
logo.gif
logo.txt
magic-number.txt
Makefile
ManagementStyle
mca.txt
md.txt
memory-barriers.txt
memory-hotplug.txt
memory.txt
mono.txt
mutex-design.txt
nmi_watchdog.txt
nommu-mmap.txt
numastat.txt
oops-tracing.txt
padata.txt
parport-lowlevel.txt
parport.txt
pi-futex.txt
pnp.txt
preempt-locking.txt
printk-formats.txt
prio_tree.txt
rbtree.txt
rfkill.txt
robust-futex-ABI.txt
robust-futexes.txt
rt-mutex-design.txt
rt-mutex.txt
rtc.txt
SAK.txt
SecurityBugs
SELinux.txt
serial-console.txt
sgi-ioc4.txt
sgi-visws.txt
SM501.txt
Smack.txt
sparse.txt
spinlocks.txt
stable_api_nonsense.txt
stable_kernel_rules.txt
SubmitChecklist
SubmittingDrivers
SubmittingPatches
svga.txt
sysfs-rules.txt
sysrq.txt documentation: update sysrq.txt magic sysrq keys 2010-10-26 17:32:41 -07:00
tomoyo.txt
unaligned-memory-access.txt
unicode.txt
unshare.txt
VGA-softcursor.txt
vgaarbiter.txt
video-output.txt
volatile-considered-harmful.txt
workqueue.txt
zorro.txt