Linus Torvalds [Wed, 30 Nov 2005 17:35:19 +0000 (09:35 -0800)]
VM: add "vm_insert_page()" function
This is what a lot of drivers will actually want to use to insert
individual pages into a user VMA. It doesn't have the old PageReserved
restrictions of remap_pfn_range(), and it doesn't complain about partial
remappings.
The page you insert needs to be a nice clean kernel allocation, so you
can't insert arbitrary page mappings with this, but that's not what
people want.
[ACPI] Add support for FADT P_LVL2_UP flag
which tells us if C2 is valid for UP-only, or SMP.
As there is no separate bit for C3, use P_LVL2_UP
bit to cover both C2 and C3.
http://bugzilla.kernel.org/show_bug.cgi?id=5165
Signed-off-by: Venkatesh Pallipadi<venkatesh.pallipadi@intel.com> Signed-off-by: Len Brown <len.brown@intel.com>
(cherry picked from 28b86b368af3944eb383078fc5797caf2dc8ce44 commit)
[ACPI] Prefer _CST over FADT for C-state capabilities
Note: This ACPI standard compliance may cause regression
on some system, if they have _CST present, but _CST value
is bogus. "nocst" module parameter should workaround
that regression.
http://bugzilla.kernel.org/show_bug.cgi?id=5165
Signed-off-by: Venkatesh Pallipadi<venkatesh.pallipadi@intel.com> Signed-off-by: Len Brown <len.brown@intel.com>
(cherry picked from 883baf7f7e81cca26f4683ae0d25ba48f094cc08 commit)
David Brownell [Mon, 28 Nov 2005 16:40:38 +0000 (08:40 -0800)]
[PATCH] USB: ehci fixups
Rename the EHCI "reset" routine so it better matches what it does (setup);
and move the one-time data structure setup earlier, before doing anything
that implicitly relies on it having been completed already.
From: David Brownell <david-b@pacbell.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch closes the IRQ race and makes various other OHCI & EHCI code
path safer vs. suspend/resume.
I've been able to (finally !) successfully suspend and resume various
Mac models, with or without USB mouse plugged, or plugging while asleep,
or unplugging while asleep etc... all without a crash.
Alan, please verify the UHCI bit I did, I only verified that it builds.
It's very simple so I wouldn't expect any issue there. If you aren't
confident, then just drop the hunks that change uhci-hcd.c
I also made the patch a little bit more "safer" by making sure the store
to the interrupt register that disables interrupts is not posted before
I set the flag and drop the spinlock.
Without this patch, you cannot reliably sleep/wakeup any recent Mac, and
I suspect PCs have some more sneaky issues too (they don't frankly crash
with machine checks because x86 tend to silently swallow PCI errors but
that won't last afaik, at least PCI Express will blow up in those
situations, but the USB code may still misbehave).
Jean Delvare [Tue, 29 Nov 2005 21:27:14 +0000 (22:27 +0100)]
[PATCH] hwmon: w83792d fix unused fan pins
1. This patch add check for fan4,5,6,7 and do not create device file
if their pins are not configured as fan.
2. Fix the issue that can not set fan divisor to 128.
3. Fix the index out of bounds bug in w83792d_detect function.
Signed-off-by: Yuan Mu <ymu@winbond.com.tw> Signed-off-by: Jean Delvare <khali@linux-fr.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Steve French [Wed, 30 Nov 2005 04:55:11 +0000 (20:55 -0800)]
[CIFS] Fix umount --force to wake up the pending response queue, not just
the request queue. Also periodically wakeup response_q so threads can
check if stuck requests have timed out. Workaround Windows server illegal smb
length on transact2 findfirst response.
Steve French [Wed, 30 Nov 2005 04:20:10 +0000 (20:20 -0800)]
[CIFS] Fix missing permission check on setattr when noperm mount option is
disabled. Also set mode, uid, gid better on mkdir and create for the
case when Unix Extensions is not enabled and setuids is enabled. This is
necessary to fix the hole in which chown could be allowed for non-root
users in some cases if root mounted, and also to display the mode and uid
properly in some cases.
Shaohua Li [Wed, 30 Nov 2005 03:34:42 +0000 (19:34 -0800)]
[PATCH] setting irq affinity is broken in ia32 with MSI enabled
Setting irq affinity stops working when MSI is enabled. With MSI, move_irq
is empty, so we can't change irq affinity. It appears a typo in Ashok's
original commit for this issue. X86_64 actually is using move_native_irq.
Signed-off-by: Shaohua Li <shaohua.li@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Roman Zippel [Wed, 30 Nov 2005 03:34:41 +0000 (19:34 -0800)]
[PATCH] hfsplus: don't modify journaled volume
Access to a journaled HFS+ volume is not officially supported under Linux, so
mount such a volume read-only, but users can override this behaviour using the
"force" mount option.
The minimum requirement to relax this check is to at least check that the
journal is empty and so nothing needs to be replayed to make sure the volume
is consistent.
Signed-off-by: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
If an external device is used for a journal, by default it will use the
entire device. The reiserfs journal code allocates structures per journal
block when it mounts the file system. If the journal device is too large,
and memory cannot be allocated for the structures, it will continue and
ultimately panic when it can't pull one off the free list.
This patch handles the allocation failure gracefully and prints an error
message at mount time.
Changes: Updated error message to be more descriptive to the user.
Discussed and approved on ReiserFS Mailing List, Nov 28.
Signed-off-by: Jeff Mahoney <jeffm@suse.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Paolo Galtieri [Wed, 30 Nov 2005 03:34:38 +0000 (19:34 -0800)]
[PATCH] ppc: fix floating point register corruption
I recently discovered a bug on PPC which causes the floating point
registers to get corrupted when CONFIG_PREEMPT=y.
The problem occurred while running a multi threaded Java application that
does floating point. The problem could be reproduced in anywhere from 2 to
6 hours. With the patch I have included below it ran for over a week
without failure.
Signed-off-by: Paolo Galtieri <pgaltieri@mvista.com> Cc: Kumar Gala <galak@gate.crashing.org> Cc: Matt Porter <mporter@kernel.crashing.org> Cc: Tom Rini <trini@kernel.crashing.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Pavel Machek [Wed, 30 Nov 2005 03:34:37 +0000 (19:34 -0800)]
[PATCH] fix swsusp on machines not supporting S4
Fix swsusp on machines not supporting S4. With recent changes, it is not
possible to trigger it using /sys filesystem. Swsusp does not really need
any support from low-level code, it is possible to reboot or halt at the
end of suspend.
Signed-off-by: Pavel Machek <pavel@suse.cz> Cc: "Brown, Len" <len.brown@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
David Gibson [Wed, 30 Nov 2005 03:34:32 +0000 (19:34 -0800)]
[PATCH] Fix crash when ptrace poking hugepage areas
set_page_dirty() will not cope with being handed a page * which is part of
a compound page, but not the master page in that compound page. This case
can occur via access_process_vm() if you attemp to write to another
process's hugepage memory area using ptrace() (causing an oops or hang).
This patch fixes the bug by only calling set_page_dirty() from
access_process_vm() if the page is not a compound page. We already use a
similar fix in bio_set_pages_dirty() for the case of direct io to
hugepages.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Acked-by: William Irwin <wli@holomorphy.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Matt Helsley [Wed, 30 Nov 2005 03:34:31 +0000 (19:34 -0800)]
[PATCH] process events connector: uid_t gid_t size issues
The uid_t and gid_t fields appear to present a 32/64-bit userspace/kernel
problem for some archs.
This patch addresses the problem by fixing the size to the largest size for
uid_t/gid_t used in the kernel. This preserves the total size of the event
structure while ensuring that the layouts of the ID change event match in
32 and 64-bit kernels and applications.
Signed-off-by: Matt Helsley <matthltc@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Paul Mackerras [Wed, 30 Nov 2005 02:20:54 +0000 (13:20 +1100)]
powerpc: Fix bug causing FP registers corruption on UP + preempt
This fixes a bug noticed by Paolo Galtieri and fixed for ARCH=ppc in
the previous commit (ppc: fix floating point register corruption).
This fixes the arch/powerpc code by adding preempt_disable/enable,
and also cleans it up a bit by pulling out the code that discards
any lazily-switched CPU register state into a new function, rather
than having that code repeated in three places.
Paolo Galtieri [Tue, 29 Nov 2005 22:26:47 +0000 (14:26 -0800)]
[PATCH] ppc: fix floating point register corruption
I recently discovered a bug on PPC which causes the floating point
registers to get corrupted when CONFIG_PREEMPT=y.
The problem occurred while running a multi threaded Java application that
does floating point. The problem could be reproduced in anywhere from 2 to
6 hours. With the patch I have included below it ran for over a week
without failure.
Signed-off-by: Paolo Galtieri <pgaltieri@mvista.com> Cc: Kumar Gala <galak@gate.crashing.org> Cc: Matt Porter <mporter@kernel.crashing.org> Cc: Tom Rini <trini@kernel.crashing.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
Adrian Bunk [Wed, 30 Nov 2005 00:28:18 +0000 (16:28 -0800)]
[NETFILTER] ipv4: small cleanups
This patch contains the following cleanups:
- make needlessly global code static
- ip_conntrack_core.c: ip_conntrack_flush() -> ip_conntrack_flush(void)
Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: David S. Miller <davem@davemloft.net>
Arjan van de Ven [Wed, 30 Nov 2005 00:21:38 +0000 (16:21 -0800)]
[NET]: Add const markers to various variables.
the patch below marks various variables const in net/; the goal is to
move them to the .rodata section so that they can't false-share
cachelines with things that get written to, as well as potentially
helping gcc a bit with optimisations. (these were found using a gcc
patch to warn about such variables)
Signed-off-by: Arjan van de Ven <arjan@infradead.org> Signed-off-by: David S. Miller <davem@davemloft.net>
[ATM]: deregistration removes device from atm_devs list immediately
atm_dev_deregister() removes device from atm_dev list immediately to
prevent operations on a phantom device. Decision to free device based
only on ->refcnt now. Remove shutdown_atm_dev() use atm_dev_deregister()
instead. atm_dev_deregister() also asynchronously releases all vccs
related to device.
Signed-off-by: Stanislaw Gruszka <stf_xl@wp.pl> Signed-off-by: Chas Williams <chas@cmf.nrl.navy.mil> Signed-off-by: David S. Miller <davem@davemloft.net>
[ATM]: avoid race conditions related to atm_devs list
Use semaphore to protect atm_devs list, as no one need access to it from
interrupt context. Avoid race conditions between atm_dev_register(),
atm_dev_lookup() and atm_dev_deregister(). Fix double spin_unlock() bug.
Signed-off-by: Stanislaw Gruszka <stf_xl@wp.pl> Signed-off-by: Chas Williams <chas@cmf.nrl.navy.mil> Signed-off-by: David S. Miller <davem@davemloft.net>
[ATM]: [lanai] kill lanai_ioctl() which just contains some old debugging code
Signed-off-by: Mitchell Blank Jr <mitch@sfgoth.com> Signed-off-by: Chas Williams <chas@cmf.nrl.navy.mil> Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Mitchell Blank Jr <mitch@sfgoth.com> Signed-off-by: Chas Williams <chas@cmf.nrl.navy.mil> Signed-off-by: David S. Miller <davem@davemloft.net>
[ATM]: atm_pcr_goal() doesn't modify its argument's contents -- mark it as const
Signed-off-by: Mitchell Blank Jr <mitch@sfgoth.com> Signed-off-by: Chas Williams <chas@cmf.nrl.navy.mil> Signed-off-by: David S. Miller <davem@davemloft.net>
Mike Stroyan [Wed, 30 Nov 2005 00:12:55 +0000 (16:12 -0800)]
[IPV4] tcp/route: Another look at hash table sizes
The tcp_ehash hash table gets too big on systems with really big memory.
It is worse on systems with pages larger than 4KB. It wastes memory that
could be better used. It also makes the netstat command slow because reading
/proc/net/tcp and /proc/net/tcp6 needs to go through the full hash table.
The default value should not be larger for larger page sizes. It seems
that the effect of page size is an unintended error dating back a long
time. I also wonder if the default value really should be a larger
fraction of memory for systems with more memory. While systems with
really big ram can afford more space for hash tables, it is not clear to
me that they benefit from increasing the allocation ratio for this table.
The amount of memory allocated is determined by net/ipv4/tcp.c:tcp_init and
mm/page_alloc.c:alloc_large_system_hash.
On i386, PAGE_SHIFT is 12 for a page size of 4K
On ia64, PAGE_SHIFT defaults to 14 for a page size of 16K
The num_physpages test above makes the allocation take a larger fraction
of the total memory on systems with larger memory. The threshold size
for a i386 system is 512MB. For an ia64 system with 16KB pages the
threshold is 2GB.
For smaller memory systems-
On i386, scale = (27 - 12) = 15
On ia64, scale = (27 - 14) = 13
For larger memory systems-
On i386, scale = (25 - 12) = 13
On ia64, scale = (25 - 14) = 11
For the rest of this discussion, I'll just track the larger memory case.
The default behavior has numentries=thash_entries=0, so the allocated
size is determined by either scale or by the default limit of 1/16 of
total memory.
At this point, numentries is pages for all of memory, rounded up to the
nearest megabyte boundary.
| /* limit to 1 bucket per 2^scale bytes of low memory */
| if (scale > PAGE_SHIFT)
| numentries >>= (scale - PAGE_SHIFT);
| else
| numentries <<= (PAGE_SHIFT - scale);
On i386, numentries >>= (13 - 12), so numentries is 1/8196 of
bytes of total memory.
On ia64, numentries <<= (14 - 11), so numentries is 1/2048 of
bytes of total memory.
bucketsize is 16, so size is 16 times numentries, rounded
down to a power of two.
On i386, size is 1/512 of bytes of total memory.
On ia64, size is 1/128 of bytes of total memory.
For smaller systems the results are
On i386, size is 1/2048 of bytes of total memory.
On ia64, size is 1/512 of bytes of total memory.
The large page effect can be removed by just replacing
the use of PAGE_SHIFT with a constant of 12 in the calls to
alloc_large_system_hash. That makes them more like the other uses of
that function from fs/inode.c and fs/dcache.c
Signed-off-by: David S. Miller <davem@davemloft.net>
Hugh Dickins [Tue, 29 Nov 2005 16:55:48 +0000 (16:55 +0000)]
[PATCH] pfnmap: do_no_page BUG_ON again
Use copy_user_highpage directly instead of cow_user_page in do_no_page:
in the immediately following page_cache_release, and elsewhere, it is
assuming that new_page is normal. If any VM_PFNMAP driver can get to
do_no_page, it's just a BUG (but not in the case of do_anonymous_page).
David S. Miller [Tue, 29 Nov 2005 21:59:03 +0000 (13:59 -0800)]
[SPARC64]: Fix >8K I/O mappings.
Increment the PFN field of the PTE so that the tests
on vm_pfn in mm/memory.c match up. The TLB ignores these
lower bits for larger page sizes, so it's OK to set things
like this.
Signed-off-by: David S. Miller <davem@davemloft.net>
Linus Torvalds [Tue, 29 Nov 2005 21:01:56 +0000 (13:01 -0800)]
Support strange discontiguous PFN remappings
These get created by some drivers that don't generally even want a pfn
remapping at all, but would really mostly prefer to just map pages
they've allocated individually instead.
For now, create a helper function that turns such an incomplete PFN
remapping call into a loop that does that explicit mapping. In the long
run we almost certainly want to export a totally different interface for
that, though.
Ben Collins [Tue, 29 Nov 2005 19:45:26 +0000 (11:45 -0800)]
[PATCH] Fix missing pfn variables caused by vm changes
I image this showed up because of "unused var..." when the changes
occured, because flush_cache_page() is a noop in most places. This
showed up for me on parisc however, where flush_cache_page() is a real
function.
Adrian Bunk [Tue, 29 Nov 2005 14:49:38 +0000 (14:49 +0000)]
[MTD] Make functions static, include header files with prototypes
This patch contains the following possible cleanups:
- every file should #include the headers containing the prototypes for
it's global functions
- make needlessly global functions static
Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Richard Purdie [Tue, 29 Nov 2005 14:28:31 +0000 (14:28 +0000)]
[MTD] chips: make sharps driver usable again
Update the pre-CFI Sharp driver sharps.c so it compiles. map_read32 /
map_write32 no longer exist in the kernel so the driver is totally broken
as it stands. The replacement functions use different parameters resulting
in the other changes.
Change collie to use this driver until someone works out why the cfi driver
fails on that machine.
Signed-off-by: Richard Purdie <rpurdie@rpsys.net> Tested-by: Pavel Machek <pavel@suse.cz> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
David Woodhouse [Thu, 17 Nov 2005 08:20:31 +0000 (08:20 +0000)]
[MTD] Make some tables 'const' so they can live in .rodata
arjan: drivers/mtd/maps/sc520cdp.c:167: warning: par_table is never written to and should be declared 'const'
arjan: drivers/mtd/maps/pci.c:105: warning: mtd_pci_map is never written to and should be declared 'const'
arjan: mind fixing those up ?
Signed-off-by: David Woodhouse <dwmw2@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Todd Poynor [Tue, 15 Nov 2005 23:28:20 +0000 (23:28 +0000)]
[MTD] CFI: Use 16-bit access to autoselect/read device id data
Recent models of Intel/Sharp and Spansion CFI flash now have significant
bits in the upper byte of device ID codes, read via what Spansion calls
"autoselect" and Intel calls "read device identifier". Currently these
values are truncated to the low 8 bits in the mtd data structures, as
all CFI read query info has previously been read one byte at a time.
Add a new method for reading 16-bit info, currently just manufacturer
and device codes; datasheets hint at future uses for upper bytes in
other fields.
Signed-off-by: Todd Poynor <tpoynor@mvista.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
[IA64] Remove getting break_num by decoding instruction
break.b always sets cr.iim to 0 and the current code tries to
get the break_num by decoding instruction. However, their
seems to be a race condition while reading the regs->cr_iip,
as on other cpu the break.b at regs->cr_iip might have been
replaced with the original instruction as a result of
unregister_kprobe() and hence decoding instruction to
obtain break_num will result in wrong value in this case.
Also includes changes to kprobes.c which now has to handle
break number zero.
Signed-off-by: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
Dean Roe [Wed, 9 Nov 2005 20:25:06 +0000 (14:25 -0600)]
[IA64] - Make pfn_valid more precise for SGI Altix systems
A single SGI Altix system can be divided into multiple partitions,
each running their own instance of the Linux kernel. pfn_valid()
is currently not optimal for any but the first partition, since it
does not compare the pfn with min_low_pfn before calling the more
costly ia64_pfn_valid().
Signed-off-by: Dean Roe <roe@sgi.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
Thomas Gleixner [Tue, 29 Nov 2005 15:57:17 +0000 (16:57 +0100)]
[JFFS2] Fix the slab cache constructor of 'struct jffs2_inode_info' objects.
JFFS2 initialize f->sem mutex as "locked" in the slab constructor which is a
bug. Objects are freed with unlocked f->sem mutex. So, when they allocated
again, f->sem is unlocked because the slab cache constructor is not called for
them. The constructor is called only once when memory pages are allocated for
objects (namely, when the slab layer allocates new slabs). So, sometimes
'struct jffs2_inode_info' are allocated with unlocked f->sem, sometimes with
locked. This is a bug. Instead, initialize f->sem as unlocked in the
constructor. I.e., in the "constructed" state f->sem must be unlocked.
From: Keijiro Yano <keijiro_yano@yahoo.co.jp> Acked-by: Artem B. Bityutskiy <dedekind@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Andrea Arcangeli [Mon, 28 Nov 2005 21:44:15 +0000 (13:44 -0800)]
[PATCH] shrinker->nr = LONG_MAX means deadlock for icache
With Andrew Morton <akpm@osdl.org>
The slab scanning code tries to balance the scanning rate of slabs versus the
scanning rate of LRU pages. To do this, it retains state concerning how many
slabs have been scanned - if a particular slab shrinker didn't scan enough
objects, we remember that for next time, and scan more objects on the next
pass.
The problem with this is that with (say) a huge number of GFP_NOIO
direct-reclaim attempts, the number of objects which are to be scanned when we
finally get a GFP_KERNEL request can be huge. Because some shrinker handlers
just bail out if !__GFP_FS.
So the patch clamps the number of objects-to-be-scanned to 2* the total number
of objects in the slab cache.
Signed-off-by: Andrea Arcangeli <andrea@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
NeilBrown [Mon, 28 Nov 2005 21:44:13 +0000 (13:44 -0800)]
[PATCH] md: fix --re-add for raid1 and raid6
If you have an array with a write-intent-bitmap, and you remove a device, then
re-add it, a full recovery isn't needed. We detect a re-add by looking at
saved_raid_disk. For raid1, it doesn't matter which disk it was, only whether
or not it was an active device. The old code being removed set a value of
'mirror' which was then ignored, so it can go. The changed code performs the
correct check.
For raid6, if there are two missing devices, make sure we chose the right slot
on --re-add rather than always the first slot.
Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
NeilBrown [Mon, 28 Nov 2005 21:44:12 +0000 (13:44 -0800)]
[PATCH] md: set default_bitmap_offset properly in set_array_info
If an array is created using set_array_info, default_bitmap_offset isn't set
properly meaning that an internal bitmap cannot be hot-added until the array
is stopped and re-assembled.
Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
NeilBrown [Mon, 28 Nov 2005 21:44:11 +0000 (13:44 -0800)]
[PATCH] md: fix problem with raid6 intent bitmap
When doing a recovery, we need to know whether the array will still be
degraded after the recovery has finished, so we can know whether bits can be
clearred yet or not. This patch performs the required check.
Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
NeilBrown [Mon, 28 Nov 2005 21:44:09 +0000 (13:44 -0800)]
[PATCH] md: improve read speed to raid10 arrays using 'far copies'
raid10 has two different layouts. One uses near-copies (so multiple
copies of a block are at the same or similar offsets of different
devices) and the other uses far-copies (so multiple copies of a block
are stored a greatly different offsets on different devices). The point
of far-copies is that it allows the first section (normally first half)
to be layed out in normal raid0 style, and thus provide raid0 sequential
read performance.
Unfortunately, the read balancing in raid10 makes some poor decisions
for far-copies arrays and you don't get the desired performance. So
turn off that bad bit of read_balance for far-copies arrays.
With this patch, read speed of an 'f2' array is comparable with a raid0
with the same number of devices, though write speed is ofcourse still
very slow.
Signed-off-by: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Rik van Riel [Mon, 28 Nov 2005 21:44:07 +0000 (13:44 -0800)]
[PATCH] temporarily disable swap token on memory pressure
Some users (hi Zwane) have seen a problem when running a workload that
eats nearly all of physical memory - th system does an OOM kill, even
when there is still a lot of swap free.
The problem appears to be a very big task that is holding the swap
token, and the VM has a very hard time finding any other page in the
system that is swappable.
Instead of ignoring the swap token when sc->priority reaches 0, we could
simply take the swap token away from the memory hog and make sure we
don't give it back to the memory hog for a few seconds.
This patch resolves the problem Zwane ran into.
Signed-off-by: Rik van Riel <riel@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>