Currently at a particular domain, each cpu in the sched group will do a
load balance at the frequency of balance_interval. More the cores and
threads, more the cpus will be in each sched group at SMP and NUMA domain.
And we endup spending quite a bit of time doing load balancing in those
domains.
Fix this by making only one cpu(first idle cpu or first cpu in the group if
all the cpus are busy) in the sched group do the load balance at that
particular sched domain and this load will slowly percolate down to the
other cpus with in that group(when they do load balancing at lower
domains).
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Christoph Lameter <clameter@engr.sgi.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Large sched domains can be very expensive to scan. Add an option SD_SERIALIZE
to the sched domain flags. If that flag is set then we make sure that no
other such domain is being balanced.
[akpm@osdl.org: build fix]
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Peter Williams <pwil3058@bigpond.net.au>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Christoph Lameter <clameter@sgi.com>
Cc: "Siddha, Suresh B" <suresh.b.siddha@intel.com>
Cc: "Chen, Kenneth W" <kenneth.w.chen@intel.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Call rebalance_tick (renamed to run_rebalance_domains) from a newly introduced
softirq.
We calculate the earliest time for each layer of sched domains to be rescanned
(this is the rescan time for idle) and use the earliest of those to schedule
the softirq via a new field "next_balance" added to struct rq.
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Peter Williams <pwil3058@bigpond.net.au>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Christoph Lameter <clameter@sgi.com>
Cc: "Siddha, Suresh B" <suresh.b.siddha@intel.com>
Cc: "Chen, Kenneth W" <kenneth.w.chen@intel.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
With SMT, if the logical processor is busy, load balance happens for every
8msec(min)-16msec(max). There is no need to do this often, as this is just
for fairness(to maintain uniform runqueue lengths) and default time slice
anyhow is 100msec.
Appended patch increases this interval to 64msec(min)-128msec(max) when the
logical processor is busy.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The present per-task IO accounting isn't very useful. It simply counts the
number of bytes passed into read() and write(). So if a process reads 1MB
from an already-cached file, it is accused of having performed 1MB of I/O,
which is wrong.
(David Wright had some comments on the applicability of the present logical IO accounting:
For billing purposes it is useless but for workload analysis it is very
useful
read_bytes/read_calls average read request size
write_bytes/write_calls average write request size
read_bytes/read_blocks ie logical/physical can indicate hit rate or thrashing
write_bytes/write_blocks ie logical/physical guess since pdflush writes can
be missed
I often look for logical larger than physical to see filesystem cache
problems. And the bytes/cpusec can help find applications that are
dominating the cache and causing slow interactive response from page cache
contention.
I want to find the IO intensive applications and make sure they are doing
efficient IO. Thus the acctcms(sysV) or csacms command would give the high
IO commands).
This patchset adds new accounting which tries to be more accurate. We account
for three things:
reads:
attempt to count the number of bytes which this process really did cause
to be fetched from the storage layer. Done at the submit_bio() level, so it
is accurate for block-backed filesystems. I also attempt to wire up NFS and
CIFS.
writes:
attempt to count the number of bytes which this process caused to be sent
to the storage layer. This is done at page-dirtying time.
The big inaccuracy here is truncate. If a process writes 1MB to a file
and then deletes the file, it will in fact perform no writeout. But it will
have been accounted as having caused 1MB of write.
So...
cancelled_writes:
account the number of bytes which this process caused to not happen, by
truncating pagecache.
We _could_ just subtract this from the process's `write' accounting. But
that means that some processes would be reported to have done negative
amounts of write IO, which is silly.
So we just report the raw number and punt this decision up to userspace.
Now, we _could_ account for writes at the physical I/O level. But
- This would require that we track memory-dirtying tasks at the per-page
level (would require a new pointer in struct page).
- It would mean that IO statistics for a process are usually only available
long after that process has exitted. Which means that we probably cannot
communicate this info via taskstats.
This patch:
Wire up the kernel-private data structures and the accessor functions to
manipulate them.
Cc: Jay Lan <jlan@sgi.com>
Cc: Shailabh Nagar <nagar@watson.ibm.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Chris Sturtivant <csturtiv@sgi.com>
Cc: Tony Ernst <tee@sgi.com>
Cc: Guillaume Thouvenin <guillaume.thouvenin@bull.net>
Cc: David Wright <daw@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
There are some kernel-only bits in the middle of <linux/futex.h> which
should be removed in what we export to userspace.
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Add rtc_merge_alarm(), which can be used by rtc drivers to turn a partially
specified alarm expiry (i.e. most significant fields set to -1, as with the
RTC_ALM_SET ioctl()) into a fully specified expiry.
If the most significant specified field is earlier than the current time, the
least significant unspecified field is incremented.
Signed-off-by: Scott Wood <scottwood@freescale.com>
Acked-by: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
freezer.h uses task_struct fields so it should include sched.h.
CC [M] fs/jfs/jfs_txnmgr.o
In file included from fs/jfs/jfs_txnmgr.c:49:
include/linux/freezer.h: In function 'frozen':
include/linux/freezer.h:9: error: dereferencing pointer to incomplete type
include/linux/freezer.h:9: error: 'PF_FROZEN' undeclared (first use in this function)
include/linux/freezer.h:9: error: (Each undeclared identifier is reported only once
include/linux/freezer.h:9: error: for each function it appears in.)
include/linux/freezer.h: In function 'freezing':
include/linux/freezer.h:17: error: dereferencing pointer to incomplete type
include/linux/freezer.h:17: error: 'PF_FREEZE' undeclared (first use in this function)
include/linux/freezer.h: In function 'freeze':
include/linux/freezer.h:26: error: dereferencing pointer to incomplete type
include/linux/freezer.h:26: error: 'PF_FREEZE' undeclared (first use in this function)
include/linux/freezer.h: In function 'do_not_freeze':
include/linux/freezer.h:34: error: dereferencing pointer to incomplete type
include/linux/freezer.h:34: error: 'PF_FREEZE' undeclared (first use in this function)
include/linux/freezer.h: In function 'thaw_process':
include/linux/freezer.h:43: error: dereferencing pointer to incomplete type
include/linux/freezer.h:43: error: 'PF_FROZEN' undeclared (first use in this function)
include/linux/freezer.h:44: warning: implicit declaration of function 'wake_up_process'
include/linux/freezer.h: In function 'frozen_process':
include/linux/freezer.h:55: error: dereferencing pointer to incomplete type
include/linux/freezer.h:55: error: dereferencing pointer to incomplete type
include/linux/freezer.h:55: error: 'PF_FREEZE' undeclared (first use in this function)
include/linux/freezer.h:55: error: 'PF_FROZEN' undeclared (first use in this function)
fs/jfs/jfs_txnmgr.c: In function 'freezing':
include/linux/freezer.h:18: warning: control reaches end of non-void function
make[2]: *** [fs/jfs/jfs_txnmgr.o] Error 1
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Acked-by: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Stabilize PIO mode transfers against a range of word sizes and FIFO
thresholds and fixes word size setup/override issues.
1) 16 and 32 bit DMA/PIO transfers broken due to timing differences.
2) Potential for bad transfer counts due to transfer size assumptions.
3) Setup function broken is multiple ways.
4) Per transfer bit_per_word changes break DMA setup in pump_tranfers.
5) False positive timeout are not errors.
6) Changes in pxa2xx_spi_chip not effective in calls to setup.
7) Timeout scaling wrong for PXA255 NSSP.
8) Driver leaks memory while busy during unloading.
Known issues:
SPI_CS_HIGH and SPI_LSB_FIRST settings in struct spi_device are not handled.
Testing:
This patch has been test against the "random length, random bits/word,
random data (verified on loopback) and stepped baud rate by octaves
(3.6MHz to 115kHz)" test. It is robust in PIO mode, using any
combination of tx and rx thresholds, and also in DMA mode (which
internally computes the thresholds).
Much thanks to Ned Forrester for exhaustive reviews, fixes and testing.
The driver is substantially better for his efforts.
Signed-off-by: Stephen Street <stephen@streetfiresound.com>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This is a long outstanding patch to finally fix the syscall interface. The
constants used for the system calls are those we have provided in our libc
patches. This patch also fixes the shmbuf and stat structure, and fcntl
definitions.
Signed-off-by: Chris Zankel <chris@zankel.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The Xtensa port contained many header files that were never needed. This
rather lengthy patch removes all those files. Unfortunately, there were
many dependencies that needed to be updated, so this patch touches quite a
few source files.
Signed-off-by: Chris Zankel <chris@zankel.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Update the architecture specific interrupt handling code for Xtensa to support
the new API. Use generic BUG macros in bug.h, and some minor fixes.
Signed-off-by: Chris Zankel <chris@zankel.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Some tuners require using cGainNormal instead of cGainLow for
high sensibility on FM reception.
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
Convert SAA7146_IER_{DIS,EN}ABLE macros to inline functions.
Fixes a problem with macro expansion (reported by C.Y.M).
Signed-off-by: Oliver Endriss <o.endriss@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
Protect the access to the IER register of the SAA7146 by the device
spinlock. I2C transfers may use interrupt mode now.
Signed-off-by: Oliver Endriss <o.endriss@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
This converts the budget-ci driver so that it uses ir-common for some of its
IR processing. In particular, the keymap for the Nova-T (sub 13c2:1011) is
switched to the Hauppauge grey/black keymap, of which the keys on the
supplied R808 remote control form a subset.
The old budget-ci keymap is moved to ir-keymaps.c and is used for other
remotes.
The debounce logic for buggy remotes (i.e. Zenith) is made conditional the
new debounce parameter and defaults to off (so that repeat keypresses aren't
ignored for all working remotes).
Some parts are based on Darren Salt's dvb-ir patchset.
Signed-off-by: David Hardeman <david@hardeman.nu>
Signed-off-by: Andrew de Quincey <adq_dvb@lidskialf.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
video_ioctl2 will auto-generate standard entries at ENUM_FMT.
Also, now, a driver may return a subset of the video array at
the return, to be stored as the current_norm.
For example, a driver may ask for V4L2_STD_PAL. At return,
driver may change it to V4L2_STD_PAL_B. This way, a futher call
to G_STD will return the exact detected video std.
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
Thanks to input from Steven Toth from Hauppauge the tveeprom module has
been extended to detect the presence of an IR transmitter (aka IR-blaster).
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
This patch adds a V4L2 driver for the OmniVision OV7670 camera.
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
A driver for the Marvell M88ALP01 "CAFE" CMOS integrated camera
controller. This driver has been renamed "cafe_ccic" since my previous
patch set.
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
Two defines for V4L2, needed by the Cafe camera driver:
1) Add the RGB444 image format
2) Add the "init" internal command which is separate from "reset".
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
- relbranch_fixup(), for non-branches, would end up setting
regs->tnpc incorrectly, in fact it would set it equal to
regs->tpc which would cause that instruction to execute twice
Also, if this is not a PC-relative branch, we should just
leave regs->tnpc as-is. This covers cases like 'jmpl' which
branch to absolute values.
- To be absolutely %100 safe, we need to flush the instruction
cache for all assignments to kprobe->ainsn.insn[], including
cases like add_aggr_kprobe()
- prev_kprobe's status field needs to be 'unsigned long' to match
the type of the value it is saving
- jprobes were totally broken:
= jprobe_return() can run in the stack frame of the jprobe handler,
or in an even deeper stack frame, thus we'll be in the wrong
register window than the one from the original probe state.
So unwind using 'restore' instructions, if necessary, right
before we do the jprobe_return() breakpoint trap.
= There is no reason to save/restore the register window saved
at %sp at jprobe trigger time. Those registers cannot be
modified by the jprobe handler. Also, this code was saving
and restoring "sizeof (struct sparc_stackf)" bytes. Depending
upon the caller, this could clobber unrelated stack frame
pieces if there is only a basic 128-byte register window
stored on the stack, without the argument save area.
So just saving and restoring struct pt_regs is sufficient.
= Kill the "jprobe_saved_esp", totally unused.
Also, delete "jprobe_saved_regs_location", with the stack frame
unwind now done explicitly by jprobe_return(), this check is
superfluous.
Signed-off-by: David S. Miller <davem@davemloft.net>
General compile fixes for 2.6.16 for sun3, and some updates to make the new
bootloader work correctly. Tested on 3/50, 3/60, 3/80.
Signed-off-by: Sam Creasey <sammy@sammy.net>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
GLIBC uses them etc.
They are guarded by ifndef __KERNEL__ so nobody will start
accidently using them in the kernel again, it's just for
userspace.
Signed-off-by: David S. Miller <davem@davemloft.net>
XFRMGRP_REPORT uses 0x10 which is a group that belongs
to events. The correct value is 0x20.
We should really be using xfrm_nlgroups going forward; it was tempting
to delete the definition of XFRMGRP_REPORT but it would break at
least iproute2.
Signed-off-by: J Hadi Salim <hadi@cyberus.ca>
Signed-off-by: David S. Miller <davem@davemloft.net>
hh_lock was converted from rwlock to seqlock by Stephen.
To have a 100% benefit of this change, I suggest to place read mostly fields
of hh_cache in a separate cache line, because hh_refcnt may be changed quite
frequently on some busy machines.
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Restore API compatibility due to bits moved from rtnetlink.h to
separate headers.
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Only the callsign but not the SSID part of an AX.25 address is ASCII
based but Linux by initializes the SSID which should be just a 4-bit
number from ASCII anyway.
Fix that and convert the code to use a shared constant for both default
addresses. While at it, use the same style for null_ax25_address also.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The hard header cache is in the main output path, so using
seqlock instead of reader/writer lock should reduce overhead.
Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Now we have a SPURR cpu feature bit, we can export it to userspace in
sysfs.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
POWER6 adds a new SPR, the data stream control register (DSCR). It can
be used to adjust how agressive the prefetch mechanisms are.
Its possible we may want to context switch this, but for now just export
it to userspace via sysfs so we can adjust it.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
pb_fnmode parameter has to be passed to usbhid, both for compatibility reasons
and also because it logically belongs there.
Also removes empty hid-input.c file in drivers/usb/input.
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
hid_input_report() was needlessly USB-specific in USB HID. This patch
makes the function independent of HID implementation and fixes all
the current users. Bluetooth patches comply with this prototype.
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
- hiddev is USB-only (agreed with Marcel Holtmann that Bluetooth currently
doesn't need it, and future planned interface (rawhid) will be more flexible
and usable)
- both HID and USB-hid can be now compiled as modules (wasn't possible before
hiddev was fully separated from generic HID layer)
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
- 'dev' in struct hid_device changed from struct usb_device to
struct device and fixed all the users
- renamed functions which are part of USB HID API from 'hid_*' to
'usbhid_*'
- force feedback initialization moved from common part into USB-specific
driver
- added usbhid.h header for USB HID API users
- removed USB-specific fields from struct hid_device and moved them
to new usbhid_device, which is pointed to by hid_device->driver_data
- fixed all USB users to use this new structure
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The "big main" split of USB HID code into generic HID code and
USB-transport specific HID handling.
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
In device-mapper I/O is sometimes queued within targets for later processing.
For example the multipath target can be configured to store I/O when no paths
are available instead of returning it -EIO.
This patch allows the device-mapper core to instruct a target to transfer the
contents of any such in-target queue back into the core. This frees up the
resources used by the target so the core can replace that target with an
alternative one and then resend the I/O to it. Without this patch the only
way to change the target in such circumstances involves returning the I/O with
an error back to the filesystem/application. In the multipath case, this
patch will let us add new paths for existing I/O to try after all the existing
paths have failed.
DMF_NOFLUSH_SUSPENDING
----------------------
If the DM_NOFLUSH_FLAG ioctl option is specified at suspend time, the
DMF_NOFLUSH_SUSPENDING flag is set in md->flags during dm_suspend(). It
is always cleared before dm_suspend() returns.
The flag must be visible while the target is flushing pending I/Os so it
is set before presuspend where the flush starts and unset after the wait
for md->pending where the flush ends.
Target drivers can check this flag by calling dm_noflush_suspending().
DM_MAPIO_REQUEUE / DM_ENDIO_REQUEUE
-----------------------------------
A target's map() function can now return DM_MAPIO_REQUEUE to request the
device mapper core queue the bio.
Similarly, a target's end_io() function can return DM_ENDIO_REQUEUE to request
the same. This has been labelled 'pushback'.
The __map_bio() and clone_endio() functions in the core treat these return
values as errors and call dec_pending() to end the I/O.
dec_pending
-----------
dec_pending() saves the pushback request in struct dm_io->error. Once all
the split clones have ended, dec_pending() will put the original bio on
the md->pushback list. Note that this supercedes any I/O errors.
It is possible for the suspend with DM_NOFLUSH_FLAG to be aborted while
in progress (e.g. by user interrupt). dec_pending() checks for this and
returns -EIO if it happened.
pushdback list and pushback_lock
--------------------------------
The bio is queued on md->pushback temporarily in dec_pending(), and after
all pending I/Os return, md->pushback is merged into md->deferred in
dm_suspend() for re-issuing at resume time.
md->pushback_lock protects md->pushback.
The lock should be held with irq disabled because dec_pending() can be
called from interrupt context.
Queueing bios to md->pushback in dec_pending() must be done atomically
with the check for DMF_NOFLUSH_SUSPENDING flag. So md->pushback_lock is
held when checking the flag. Otherwise dec_pending() may queue a bio to
md->pushback after the interrupted dm_suspend() flushes md->pushback.
Then the bio would be left in md->pushback.
Flag setting in dm_suspend() can be done without md->pushback_lock because
the flag is checked only after presuspend and the set value is already
made visible via the target's presuspend function.
The flag can be checked without md->pushback_lock (e.g. the first part of
the dec_pending() or target drivers), because the flag is checked again
with md->pushback_lock held when the bio is really queued to md->pushback
as described above. So even if the flag is cleared after the lockless
checkings, the bio isn't left in md->pushback but returned to applications
with -EIO.
Other notes on the current patch
--------------------------------
- md->pushback is added to the struct mapped_device instead of using
md->deferred directly because md->io_lock which protects md->deferred is
rw_semaphore and can't be used in interrupt context like dec_pending(),
and md->io_lock protects the DMF_BLOCK_IO flag of md->flags too.
- Don't issue lock_fs() in dm_suspend() if the DM_NOFLUSH_FLAG
ioctl option is specified, because I/Os generated by lock_fs() would be
pushed back and never return if there were no valid devices.
- If an error occurs in dm_suspend() after the DMF_NOFLUSH_SUSPENDING
flag is set, md->pushback must be flushed because I/Os may be queued to
the list already. (flush_and_out label in dm_suspend())
Test results
------------
I have tested using multipath target with the next patch.
The following tests are for regression/compatibility:
- I/Os succeed when valid paths exist;
- I/Os fail when there are no valid paths and queue_if_no_path is not
set;
- I/Os are queued in the multipath target when there are no valid paths and
queue_if_no_path is set;
- The queued I/Os above fail when suspend is issued without the
DM_NOFLUSH_FLAG ioctl option. I/Os spanning 2 multipath targets also
fail.
The following tests are for the normal code path of new pushback feature:
- Queued I/Os in the multipath target are flushed from the target
but don't return when suspend is issued with the DM_NOFLUSH_FLAG
ioctl option;
- The I/Os above are queued in the multipath target again when
resume is issued without path recovery;
- The I/Os above succeed when resume is issued after path recovery
or table load;
- Queued I/Os in the multipath target succeed when resume is issued
with the DM_NOFLUSH_FLAG ioctl option after table load. I/Os
spanning 2 multipath targets also succeed.
The following tests are for the error paths of the new pushback feature:
- When the bdget_disk() fails in dm_suspend(), the
DMF_NOFLUSH_SUSPENDING flag is cleared and I/Os already queued to the
pushback list are flushed properly.
- When suspend with the DM_NOFLUSH_FLAG ioctl option is interrupted,
o I/Os which had already been queued to the pushback list
at the time don't return, and are re-issued at resume time;
o I/Os which hadn't been returned at the time return with EIO.
Signed-off-by: Kiyoshi Ueda <k-ueda@ct.jp.nec.com>
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Cc: dm-devel@redhat.com
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Provide a dm ioctl option to request noflush suspending. (See next patch for
what this is for.) As the interface is extended, the version number is
incremented.
Other than accepting the new option through the interface, There is no change
to existing behaviour.
Test results:
Confirmed the option is given from user-space correctly.
Signed-off-by: Kiyoshi Ueda <k-ueda@ct.jp.nec.com>
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Cc: dm-devel@redhat.com
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Tighten the use of return values from the target map and end_io functions.
Values of 2 and above are now explictly reserved for future use. There are no
existing targets using such values.
The patch has no effect on existing behaviour.
o Reserve return values of 2 and above from target map functions.
Any positive value currently indicates "mapping complete", but all
existing drivers use the value 1. We now make that a requirement
so we can assign new meaning to higher values in future.
The new definition of return values from target map functions is:
< 0 : error
= 0 : The target will handle the io (DM_MAPIO_SUBMITTED).
= 1 : Mapping completed (DM_MAPIO_REMAPPED).
> 1 : Reserved (undefined). Previously this was the same as '= 1'.
o Reserve return values of 2 and above from target end_io functions
for similar reasons.
DM_ENDIO_INCOMPLETE is introduced for a return value of 1.
Test results:
I have tested by using the multipath target.
I/Os succeed when valid paths exist.
I/Os are queued in the multipath target when there are no valid paths and
queue_if_no_path is set.
I/Os fail when there are no valid paths and queue_if_no_path is not set.
Signed-off-by: Kiyoshi Ueda <k-ueda@ct.jp.nec.com>
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Cc: dm-devel@redhat.com
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Siddha, Suresh B