Commit graph

182536 commits

Author SHA1 Message Date
Michael Holzheu
0cbde8ee60 [S390] zcore: Add prefix registers to dump header
With this patch the prefix registers of all online CPUs are stored in the
the zcore dump header. This allows dump analysis tools to access the register
information that is stored in the prefix pages without using the System.map.

Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-26 22:37:33 +01:00
Martin Schwidefsky
13c6680acb [S390] correct vdso version string
The glibc vdso code for s390 uses the version string 2.6.29, the
kernel uses the version string 2.6.26. No wonder the vdso code
is never used. The first kernel version to contain the vdso code
is 2.6.29 which makes this the correct version.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-26 22:37:33 +01:00
Martin Schwidefsky
1844c9bc0b [S390] add support for compressed kernels
Add the "bzImage" compile target and the necessary code  to generate
compressed kernel images. The old style uncompressed "image" target
is preserved, a simple make will build them both.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-26 22:37:33 +01:00
Michael Holzheu
73bfa5f2f7 [S390] Define new s390 ELF note sections in elf.h
S390 ELF core dump currently only contains the PSW, the general purpose
registers, the floating point registers and the access registers stored
in PRSTATUS/PRFPREG note sections.
For analyzing s390 kernel problems additional registers are important.
In order to be able to include these registers to a kernel ELF core dump,
this patch adds the following five new note sections to elf.h:

* NT_S390_TIMER:   S390 timer register
* NT_S390_TODCMP:  S390 TOD comparator register
* NT_S390_TODPREG: S390 TOD programmable register
* NT_S390_CTRS:    S390 control registers
* NT_S390_PREFIX:  S390 prefix register

The new note sections have been already defined and accepted in the upstream
binutils package.

Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-26 22:37:33 +01:00
Martin Schwidefsky
61fd330dee [S390] codepage conversion of kernel parameter line
Move the ebcdic to ascii conversion of the kernel parameter line from
head.S to early.c and convert the assembler code to C.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-26 22:37:32 +01:00
Alexey Dobriyan
34b9243a30 [S390] seq_file: convert drivers/s390/
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-26 22:37:32 +01:00
Martin Schwidefsky
618708ff04 [S390] add z9-ec/z10 instruction to kernel disassembler
Add the instruction of the z9-ec and z10 machines to the kernel disassembler.
Add the missing "ptff" instruction of z9-109 and the missing "sqd" of g5.
Remove useless comments with instruction examples from format table.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-26 22:37:32 +01:00
Stefan Haberland
b695adfaa1 [S390] dasd: correct offline processing
Flushing the dasd ccw request queue may stop the processing of the
block device request queue. Destroy partitions may wait for
outstanding requests and thus hang.
Swapping dasd_destroy_partitions and dasd_flush_request_queue so that
the request queue is empty before dasd_destroy_partitions is called.

Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-26 22:37:32 +01:00
Stefan Haberland
589c74d507 [S390] dasd: fix refcounting.
The function dasd_device_from_cdev returns a reference to the dasd
device and increases the refcount by one. If an exception occurs,
the refcount was not decreased in all cases
e.g. in dasd_discipline_show.
Prevent the offline processing from hang by correcting two functions
to decrease the refcount even if an error occured.

Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-26 22:37:32 +01:00
Stefan Haberland
9eb251225a [S390] dasd: fix online/offline race
Setting a DASD online and offline in quick succession may cause
a kernel panic or let the chhccwdev command wait forever.
The Online process is split into two parts. After the first part
is finished the offline process may be called. This may result
in a situation where the second online processing part tries to
set the DASD offline as well.
Use a mutex to protect online and offline against each other.
Also correct some checking.

Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-26 22:37:32 +01:00
Heiko Carstens
22e0a04672 [S390] use kprobes_built_in() in mm/fault code
Use kprobes_built_in() to avoid ifdefs like most other architectures do.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-26 22:37:32 +01:00
Heiko Carstens
52499f4026 [S390] bug: use relative pointers in bug table entries
Reduces the size of the bug table entries by 50% on 64bit kernels.
Saves around 30kb on a defconfig kernel.
s390 version of b93a531e "allow bug table entries to use relative
pointers (and use it on x86-64)".

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-26 22:37:31 +01:00
Heiko Carstens
cbb870c822 [S390] Cleanup struct _lowcore usage and defines.
Use asm offsets to make sure the offset defines to struct _lowcore and
its layout don't get out of sync.
Also add a BUILD_BUG_ON() which checks that the size of the structure
is sane.
And while being at it change those sites which use odd casts to access
the current lowcore. These should use S390_lowcore instead.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-26 22:37:31 +01:00
Heiko Carstens
d96221ab1e [S390] free_initmem: reduce code duplication
free_initmem() and free_initrd_mem() are nearly identical. So make them
call a common function.
Also fixes a bug: if the initrd wouldn't start on a page boundary also
memory after the initrd would be initialized with the poison value.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-26 22:37:31 +01:00
Heiko Carstens
b8e660b83d [S390] Replace ENOTSUPP usage with EOPNOTSUPP
ENOTSUPP is not supposed to leak to userspace so lets just use
EOPNOTSUPP everywhere.
Doesn't fix a bug, but makes future reviews easier.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-26 22:37:31 +01:00
Gerald Schaefer
59b6978745 [S390] spinlock: check virtual cpu running status
This patch introduces a new function that checks the running status
of a cpu in a hypervisor. This status is not virtualized, so the check
is only correct if running in an LPAR. On acquiring a spinlock, if the
cpu holding the lock is scheduled by the hypervisor, we do a busy wait
on the lock. If it is not scheduled, we yield over to that cpu.

Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-26 22:37:31 +01:00
Heiko Carstens
8387c736fc [S390] sysinfo: fix SYSIB 3,2,2 structure
The size of the field that contains the description block count is
only four bits instead of eight bits.
The first four bits are reserved but this might change and break.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-26 22:37:31 +01:00
Martin Schwidefsky
27d71602b4 [S390] add MACHINE_IS_LPAR flag
Introduce the MACHINE_IS_LPAR flag for code that should only be
executed if Linux is running in an LPAR.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-26 22:37:31 +01:00
Jan Glauber
432ac5e04b [S390] qdio: optimize cache line usage of struct qdio_irq
Remove a memset hack that relied on the internal layout of the
qdio_irq struct and move the per device statistics data into an own
cache line to avoid cache line bashing between the inbound and the
outbound queue tasklets. Also reduce the number of allocated queues
from 32 to 4 which is the current maximum. That saves a cache line
in struct qdio_irq.

Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-26 22:37:31 +01:00
Jan Glauber
d307297f73 [S390] qdio: account processed SBAL during queue scan
Add counters for the number of processed SBALs. The numbers summarize
how many SBALs were processed at each queue scan and indicate the
utilization of the queue. Furthermore the number of unsuccessfull
queue scans, SBAL errors and the total number of processed
SBALs are accounted.

Also regroup struct qdio_q to move read-mostly and write-mostly data
into different cachelines.

Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-26 22:37:30 +01:00
Heiko Carstens
a93b8ec1df [S390] smp: rework sigp code
Rename signal_processor* functions to sigp*.
Add raw variants of each version, so we can get rid of the hacks played
in smp code which establish temporary cpu logical mappings so they could
call the sigp functions.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-26 22:37:30 +01:00
Heiko Carstens
2c2df118a6 [S390] smp: always reboot on cpu 0
Always reboot on logical cpu 0. This makes sure that the IPL cpu is
always the same and usually avoids strange numbering schemes between
physical and logical cpus.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-26 22:37:30 +01:00
Heiko Carstens
abd1ecf209 [S390] smp: rename and add lowcore defines
Rename __LC_RESTART_PSW to __LC_RST_NEW_PSW, add a define for the
missing 32 bit variant and the missing old PSWs.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-26 22:37:30 +01:00
Heiko Carstens
f64ca21714 [S390] zfcpdump: remove cross arch dump support
Remove support to be able to dump 31 bit systems with a 64 bit dumper.
This is mostly useless since no distro ships 31 bit kernels together
with a 64 bit dumper.
We also get rid of a bit of hacky code.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-26 22:37:30 +01:00
Martin Schwidefsky
987bcdacb1 [S390] use inline assembly contraints available with gcc 3.3.3
Drop support to compile the kernel with gcc versions older than 3.3.3.
This allows us to use the "Q" inline assembly contraint on some more
inline assemblies without duplicating a lot of complex code (e.g. __xchg
and __cmpxchg). The distinction for older gcc versions can be removed
which saves a few lines and simplifies the code.

Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-26 22:37:30 +01:00
Heiko Carstens
d1bf85902c [S390] cio: fix storage key handling
Some parts of cio do not shift PAGE_DEFAULT_KEY correctly and end up
with an incorrect key in their data structures.
Since the default key is zero this doesn't really matter. However if
somebody would use key-controlled protection for debugging purposes
it would be quite helpful if all of this would work as expected.

Also remove a stale declaration.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-26 22:37:30 +01:00
Sebastian Ott
0d01bb8922 [S390] cio: trigger subchannel event at resume time
ccw_device_pm_restore: trigger subchannel event to better handle
changes to the subchannel device.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-26 22:37:30 +01:00
Sebastian Ott
76e6fb4b86 [S390] ccw_device_notify: improve return codes
Callers of ccw_device_notify could not distinguish between a driver
who has no notifier registered and a driver who doesn't want to keep
a device after a certain event. Change this by adding proper return
codes.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-26 22:37:29 +01:00
Sebastian Ott
b4c707214c [S390] cio: make wait_events interruptible
Make the potentially long blocking wait_event's used by the cio
settle mechanism interruptible.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-26 22:37:29 +01:00
Sebastian Ott
b4563e891a [S390] cio: wait for channel report
To fetch a pending channel report word (crw) we use a kernel
thread which triggers stcrw and sleeps on a semaphore. The s390
machine check handler uses crw_handle_channel_report to handle
one crw if needed.

This patch replaces the semaphore with a waitqueue (to block the
kernel thread) and an atomic_t (to count the number of pending
requests).

By this we achieve the ability to force this thread to check for
a pending crw (independent on when it is triggered by the machine
check handler) and wait for this action to finish.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-26 22:37:29 +01:00
Sebastian Ott
879acca58a [S390] cio: introduce cio_settle
This patch introduces a proc file cio_settle. A write request to
this file is blocked until all queued cio actions are handled.

This will allow userspace to wait for pending work affecting
device availability after changing cio_ignore or the hardware
configuration.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-26 22:37:29 +01:00
Sebastian Ott
be5d3823f2 [S390] cio: consolidate workqueues
We used to maintain 2 singlethreaded workqueues for synchronization
and to trigger work from interrupt context. Since our latest cio
changes we only use one of these workqueues. So get rid of the
unused workqueue, rename the remaining one to "cio_work_q" and move
its ownership to the channel subsystem driver.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-26 22:37:29 +01:00
Ursula Braun
6f5d09a0e9 [S390] adapt text to cu3088-removal
cu3088 layer for lcs and ctcm has been removed. Thus the reference
to cu3088 in this text is to be removed as well.

Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-26 22:37:29 +01:00
Heiko Carstens
1dcec254af [S390] uaccess: implement strict user copy checks
Same as on x86 and sparc, besides the fact that enabling the option
will just emit compile time warnings instead of errors.
Keeps allyesconfig kernels compiling.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-02-26 22:37:29 +01:00
Konrad Rzeszutek Wilk
c4d1409bbe ibft: Update MAINTAINERS file.
Provide the right e-mail and names for me and Peter.

Signed-off-by: Konrad Rzeszutek Wilk <konrad@kernel.org>
2010-02-26 21:02:15 +00:00
Joe Perches
00e7825b94 drivers/firmware/iscsi_ibft.c: remove NIPQUAD_FMT, use %pI4
Convert netmask to __be32 and format it with %pI4

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Konrad Rzeszutek <ketuzsezr@darnok.org>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Cc: Peter Jones <pjones@redhat.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2010-02-26 21:02:14 +00:00
Alex Elder
398007f863 Merge branch 'linux-2.6.33' 2010-02-26 14:34:02 -06:00
Rafael J. Wysocki
a9c9b4429d PM / Hibernate: Fix preallocating of memory
The hibernate memory preallocation code allocates memory to push some
user space data out of physical RAM, so that the hibernation image is
not too large.  It allocates more memory than necessary for creating
the image, so it has to release some pages to make room for
allocations made while suspending devices and disabling nonboot CPUs,
or the system will hang due to the lack of free pages to allocate
from.  Unfortunately, the function used for freeing these pages,
free_unnecessary_pages(), contains a bug that prevents it from doing
the job on all systems without highmem.

Fix this problem, which is a regression from the 2.6.30 kernel, by
using the right condition for the termination of the loop in
free_unnecessary_pages().

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Reported-and-tested-by: Alan Jenkins <sourcejedi.lkml@googlemail.com>
Cc: stable@kernel.org
2010-02-26 20:39:13 +01:00
Jiri Slaby
f8bb0db818 PM / Hibernate: Remove swsusp.c finally
Its contents and entry in Makefile were already removed in
8e60c6a134
(Shift remaining code from swsusp.c to hibernate.c)
but somehow it remained in-place (rjw: which most likely was my
mistake).

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Acked-by: Nigel Cunningham <nigel@tuxonice.net>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2010-02-26 20:39:13 +01:00
Frans Pop
07c3bb5797 PM / Hibernate: Remove trailing space in message
Remove a trailing space from a message in swsusp_save().

Signed-off-by: Frans Pop <elendil@planet.nl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2010-02-26 20:39:13 +01:00
Rafael J. Wysocki
4cb077d93a PM: Allow SCSI devices to suspend/resume asynchronously
Set power.async_suspend for all SCSI devices, targets and hosts, so
that they can be suspended and resumed in parallel with the main
suspend/resume thread and possibly with other devices they don't
depend on in a known way (i.e. devices which are not their parents or
children).

The power.async_suspend flag is also set for devices that don't have
suspend or resume callbacks, because otherwise they would make the
main suspend/resume thread wait for their "asynchronous" children
(during suspend) or parents (during resume), effectively negating the
possible gains from executing these devices' suspend and resume
callbacks asynchronously.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2010-02-26 20:39:12 +01:00
Rafael J. Wysocki
927bc9165d PM: Allow USB devices to suspend/resume asynchronously
Set power.async_suspend for USB devices, endpoints and interfaces,
allowing them to be suspended and resumed asynchronously during
system sleep transitions.

The power.async_suspend flag is also set for devices that don't have
suspend or resume callbacks, because otherwise they would make the
main suspend/resume thread wait for their "asynchronous" children
(during suspend) or parents (during resume), effectively negating the
possible gains from executing these devices' suspend and resume
callbacks asynchronously.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2010-02-26 20:39:12 +01:00
Alan Stern
6d19c009cc USB: implement non-tree resume ordering constraints for PCI host controllers
This patch (as1331) adds non-tree ordering constraints needed for
proper resume of PCI USB host controllers from hibernation.  The main
issue is that non-high-speed devices must not be resumed before the
high-speed root hub, because it is the ehci_bus_resume() routine which
takes care of handing the device connection over to the companion
controller.  If the device resume is attempted before the handover
then the device won't be found and it will be treated as though it had
disconnected.

The patch adds a new field to the usb_bus structure; for each
full/low-speed bus this field will contain a pointer to the companion
high-speed bus (if one exists).  It is used during normal device
resume; if the hs_companion pointer isn't NULL then we wait for the
root-hub device on the hs_companion bus.

A secondary issue is that an EHCI controlller shouldn't be resumed
before any of its companions.  On some machines I have observed
handovers failing if the companion controller is reinitialized after
the handover.  Thus, the EHCI resume routine must wait for the
companion controllers to be resumed.

The patch also fixes a small bug in usb_hcd_pci_probe(); an error path
jumps to the wrong label, causing a memory leak.

[rjw: Fixed compilation for CONFIG_PM_SLEEP unset.]

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2010-02-26 20:39:12 +01:00
Rafael J. Wysocki
a1e4d72cd3 PM: Allow PCI devices to suspend/resume asynchronously
Set power.async_suspend for all PCI devices and PCIe port services,
so that they can be suspended and resumed in parallel with other
devices they don't depend on in a known way (i.e. devices which are
not their parents or children).

This only affects the "regular" suspend and resume stages, which
means in particular that the restoration of the PCI devices' standard
configuration registers during resume will still be carried out
synchronously (at the "early" resume stage).

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2010-02-26 20:39:12 +01:00
Jiri Slaby
09c09bc618 PM / Hibernate: Swap, remove useless check from swsusp_read()
It will never reach here if the sws_resume_bdev is erratic.
swsusp_read() is called only from software_resume(), but after
swsusp_check() which would catch the error state.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2010-02-26 20:39:11 +01:00
Jiri Slaby
b694e52ebd PM / Hibernate: Really deprecate deprecated user ioctls
They were deprecated and removed from exported headers more than 2
years ago. Inform users about their removal in the future now.

(Switch cases needed to be reorderded for an easy fall through.)

And add an entry to feature-removal-schedule.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2010-02-26 20:39:11 +01:00
Rafael J. Wysocki
f8824cee40 PM: Allow device drivers to use dpm_wait()
There are some dependencies between devices (in particular, between
EHCI USB controllers and their OHCI/UHCI siblings) which are not
reflected by the structure of the device tree.  With synchronous
suspend and resume these dependencies are taken into accout
automatically, because the devices in question are always registered
in the right order, but to meet these constraints with asynchronous
suspend and resume the drivers of these devices will need to use
dpm_wait() in their suspend/resume routines, so introduce a helper
function allowing them to do that.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2010-02-26 20:39:11 +01:00
Rafael J. Wysocki
97df8c1299 PM: Start asynchronous resume threads upfront
It has been shown by testing that total device resume time can be
reduced significantly (by as much as 50% or more) if the async
threads executing some devices' resume routines are all started
before the main resume thread starts to handle the "synchronous"
devices.

This is a consequence of the fact that the slowest devices tend to be
located at the end of dpm_list, so their resume routines are started
very late.  Consequently, they have to wait for all the preceding
"synchronous" devices before their resume routines can be started
by the main resume thread, even if they are "asynchronous".  By
starting their async threads upfront we effectively move those
devices towards the beginning of dpm_list, without breaking their
ordering with respect to their parents and children.  As a result,
their resume routines are started much earlier and we are able to
save much more device resume time this way.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2010-02-26 20:39:11 +01:00
Rafael J. Wysocki
5a2eb8585f PM: Add facility for advanced testing of async suspend/resume
Add configuration switch CONFIG_PM_ADVANCED_DEBUG for compiling in
extra PM debugging/testing code allowing one to access some
PM-related attributes of devices from the user space via sysfs.

If CONFIG_PM_ADVANCED_DEBUG is set, add sysfs attribute power/async
for every device allowing the user space to access the device's
power.async_suspend flag and modify it, if desired.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2010-02-26 20:39:10 +01:00
Rafael J. Wysocki
0e06b4a891 PM: Add a switch for disabling/enabling asynchronous suspend/resume
Add sysfs attribute /sys/power/pm_async allowing the user space to
disable/enable asynchronous suspend/resume of devices.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2010-02-26 20:39:10 +01:00