A bug was brought to my attention against a distro kernel but it affects
mainline and I believe problems like this have been reported in various
guises on the mailing lists although I don't have specific examples at the
moment.
The reported problem was that malloc() stalled for a long time (minutes in
some cases) if a large tmpfs mount was occupying a large percentage of
memory overall. The pages did not get cleaned or reclaimed by
zone_reclaim() because the zone_reclaim_mode was unsuitable, but the lists
are uselessly scanned frequencly making the CPU spin at near 100%.
This patchset intends to address that bug and bring the behaviour of
zone_reclaim() more in line with expectations which were noticed during
investigation. It is based on top of mmotm and takes advantage of
Kosaki's work with respect to zone_reclaim().
Patch 1 fixes the heuristics that zone_reclaim() uses to determine if the
scan should go ahead. The broken heuristic is what was causing the
malloc() stall as it uselessly scanned the LRU constantly. Currently,
zone_reclaim is assuming zone_reclaim_mode is 1 and historically it
could not deal with tmpfs pages at all. This fixes up the heuristic so
that an unnecessary scan is more likely to be correctly avoided.
Patch 2 notes that zone_reclaim() returning a failure automatically means
the zone is marked full. This is not always true. It could have
failed because the GFP mask or zone_reclaim_mode were unsuitable.
Patch 3 introduces a counter zreclaim_failed that will increment each
time the zone_reclaim scan-avoidance heuristics fail. If that
counter is rapidly increasing, then zone_reclaim_mode should be
set to 0 as a temporarily resolution and a bug reported because
the scan-avoidance heuristic is still broken.
This patch:
On NUMA machines, the administrator can configure zone_reclaim_mode that
is a more targetted form of direct reclaim. On machines with large NUMA
distances for example, a zone_reclaim_mode defaults to 1 meaning that
clean unmapped pages will be reclaimed if the zone watermarks are not
being met.
There is a heuristic that determines if the scan is worthwhile but the
problem is that the heuristic is not being properly applied and is
basically assuming zone_reclaim_mode is 1 if it is enabled. The lack of
proper detection can manfiest as high CPU usage as the LRU list is scanned
uselessly.
Historically, once enabled it was depending on NR_FILE_PAGES which may
include swapcache pages that the reclaim_mode cannot deal with. Patch
vmscan-change-the-number-of-the-unmapped-files-in-zone-reclaim.patch by
Kosaki Motohiro noted that zone_page_state(zone, NR_FILE_PAGES) included
pages that were not file-backed such as swapcache and made a calculation
based on the inactive, active and mapped files. This is far superior when
zone_reclaim==1 but if RECLAIM_SWAP is set, then NR_FILE_PAGES is a
reasonable starting figure.
This patch alters how zone_reclaim() works out how many pages it might be
able to reclaim given the current reclaim_mode. If RECLAIM_SWAP is set in
the reclaim_mode it will either consider NR_FILE_PAGES as potential
candidates or else use NR_{IN}ACTIVE}_PAGES-NR_FILE_MAPPED to discount
swapcache and other non-file-backed pages. If RECLAIM_WRITE is not set,
then NR_FILE_DIRTY number of pages are not candidates. If RECLAIM_SWAP is
not set, then NR_FILE_MAPPED are not.
[kosaki.motohiro@jp.fujitsu.com: Estimate unmapped pages minus tmpfs pages]
[fengguang.wu@intel.com: Fix underflow problem in Kosaki's estimate]
Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Reviewed-by: Rik van Riel <riel@redhat.com>
Acked-by: Christoph Lameter <cl@linux-foundation.org>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The per-task oom_adj value is a characteristic of its mm more than the
task itself since it's not possible to oom kill any thread that shares the
mm. If a task were to be killed while attached to an mm that could not be
freed because another thread were set to OOM_DISABLE, it would have
needlessly been terminated since there is no potential for future memory
freeing.
This patch moves oomkilladj (now more appropriately named oom_adj) from
struct task_struct to struct mm_struct. This requires task_lock() on a
task to check its oom_adj value to protect against exec, but it's already
necessary to take the lock when dereferencing the mm to find the total VM
size for the badness heuristic.
This fixes a livelock if the oom killer chooses a task and another thread
sharing the same memory has an oom_adj value of OOM_DISABLE. This occurs
because oom_kill_task() repeatedly returns 1 and refuses to kill the
chosen task while select_bad_process() will repeatedly choose the same
task during the next retry.
Taking task_lock() in select_bad_process() to check for OOM_DISABLE and in
oom_kill_task() to check for threads sharing the same memory will be
removed in the next patch in this series where it will no longer be
necessary.
Writing to /proc/pid/oom_adj for a kthread will now return -EINVAL since
these threads are immune from oom killing already. They simply report an
oom_adj value of OOM_DISABLE.
Cc: Nick Piggin <npiggin@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Some bit ranges were inclusive and some not. Fix them to be consistently
inclusive.
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Matt Mackall <mpm@selenic.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
ALLOC_WMARK_MIN, ALLOC_WMARK_LOW and ALLOC_WMARK_HIGH determin whether
pages_min, pages_low or pages_high is used as the zone watermark when
allocating the pages. Two branches in the allocator hotpath determine
which watermark to use.
This patch uses the flags as an array index into a watermark array that is
indexed with WMARK_* defines accessed via helpers. All call sites that
use zone->pages_* are updated to use the helpers for accessing the values
and the array offsets for setting.
Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Reviewed-by: Christoph Lameter <cl@linux-foundation.org>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Dave Hansen <dave@linux.vnet.ibm.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The Makefiles in the build directories use the internal make variable
MAKEFILE_LIST which is available from make 3.80 only. (The patch would be
valid back to 2.6.25)
Signed-off-by: Adam Lackorzynski <adam@os.inf.tu-dresden.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
There is sometimes a need for the ocores driver to add devices to the
bus when installed.
i2c_register_board_info can not always be used, because the I2C devices
are not known at an early state, they could for instance be connected
on a I2C bus on a PCI device which has the Open Cores IP.
i2c_new_device can not be used in all cases either since the resulting
bus nummer might be unknown.
The solution is the pass a list of I2C devices in the platform data to
the Open Cores driver. This is useful for MFD drivers.
Signed-off-by: Richard Röjfors <richard.rojfors.ext@mocean-labs.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Remove the ->suspend_late() and ->resume_early() callbacks
from struct bus_type V2. These callbacks are legacy stuff
at this point and since there seem to be no in-tree users
we may as well remove them. New users should use dev_pm_ops.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Acked-by: Pavel Machek <pavel@ucw.cz>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
It is outdated here and can be found in the MAINTAINERS file. Also
remove the URL of the previous maintainer, similar content can be found
in the SubmittingPatches file.
Signed-off-by: Markus Heidelberg <markus.heidelberg@web.de>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Remove a period from end of command-line and fix misplaced comma.
Signed-off-by: Masanori Kobayasi <zap03216@nifty.ne.jp>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
The first formal parameter of the rb_link_node() is a pointer, and the
"node" is define a data struct (pls see line 67 and line 73 in the
doc), so the actual parameter should use "&data->node".
Signed-off-by: Figo.zhang <figo.zhang@kolorific.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Support the VIRTIO_RING_F_INDIRECT_DESC feature.
This is a simple matter of changing the descriptor walking
code to operate on a struct vring_desc* and supplying it
with an indirect table if detected.
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
The Guest only really needs to tell us about activity when we're going
to listen to the eventfd: normally, we don't want to know.
So if there are no available buffers, turn on notifications, re-check,
then wait for the Guest to notify us via the eventfd, then turn
notifications off again.
There's enough else going on that the differences are in the noise.
Before: Secs RxKicks TxKicks
1G TCP Guest->Host: 3.94 4686 32815
1M normal pings: 104 142862 1000010
1M 1k pings (-l 120): 57 142026 1000007
After:
1G TCP Guest->Host: 3.76 4691 32811
1M normal pings: 111 142859 997467
1M 1k pings (-l 120): 55 19648 501549
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Rather than triggering an interrupt every time, we only trigger an
interrupt when there are no more incoming packets (or the recv queue
is full).
However, the overhead of doing the select to figure this out is
measurable: 1M pings goes from 98 to 104 seconds, and 1G Guest->Host
TCP goes from 3.69 to 3.94 seconds. It's close to the noise though.
I tested various timeouts, including reducing it as the number of
pending packets increased, timing a 1 gigabyte TCP send from Guest ->
Host and Host -> Guest (GSO disabled, to increase packet rate).
// time tcpblast -o -s 65536 -c 16k 192.168.2.1:9999 > /dev/null
Timeout Guest->Host Pkts/irq Host->Guest Pkts/irq
Before 11.3s 1.0 6.3s 1.0
0 11.7s 1.0 6.6s 23.5
1 17.1s 8.8 8.6s 26.0
1/pending 13.4s 1.9 6.6s 23.8
2/pending 13.6s 2.8 6.6s 24.1
5/pending 14.1s 5.0 6.6s 24.4
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
If we track how many buffers we've used, we can tell whether we really
need to interrupt the Guest. This happens as a side effect of
spurious notifications.
Spurious notifications happen because it can take a while before the
Host thread wakes up and sets the VRING_USED_F_NO_NOTIFY flag, and
meanwhile the Guest can more notifications.
A real fix would be to use wake counts, rather than a suppression
flag, but the practical difference is generally in the noise: the
interrupt is usually coalesced into a pending one anyway so we just
save a system call which isn't clearly measurable.
Secs Spurious IRQS
1G TCP Guest->Host: 3.93 58
1M normal pings: 100 72
1M 1k pings (-l 120): 57 492904
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Rather than sending an interrupt on every buffer, we only send an interrupt
when we're about to wait for the Guest to send us a new one. The console
input and network input still send interrupts manually, but the block device,
network and console output queues can simply rely on this logic to send
interrupts to the Guest at the right time.
The patch is cluttered by moving trigger_irq() higher in the code.
In practice, two factors make this optimization less interesting:
(1) we often only get one input at a time, even for networking,
(2) triggering an interrupt rapidly tends to get coalesced anyway.
Before: Secs RxIRQS TxIRQs
1G TCP Guest->Host: 3.72 32784 32771
1M normal pings: 99 1000004 995541
100,000 1k pings (-l 120): 5 49510 49058
After:
1G TCP Guest->Host: 3.69 32809 32769
1M normal pings: 99 1000004 996196
100,000 1k pings (-l 120): 5 52435 52361
(Note the interrupt count on 100k pings goes *up*: see next patch).
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Currently lguest has three threads: the main Launcher thread, a Waker
thread, and a thread for the block device (because synchronous block
was simply too painful to bear).
The Waker selects() on all the input file descriptors (eg. stdin, net
devices, pipe to the block thread) and when one becomes readable it calls
into the kernel to kick the Launcher thread out into userspace, which
repeats the poll, services the device(s), and then tells the kernel to
release the Waker before re-entering the kernel to run the Guest.
Also, to make a slightly-decent network transmit routine, the Launcher
would suppress further network interrupts while it set a timer: that
signal handler would write to a pipe, which would rouse the Waker
which would prod the Launcher out of the kernel to check the network
device again.
Now we can convert all our virtqueues to separate threads: each one has
a separate eventfd for when the Guest pokes the device, and can trigger
interrupts in the Guest directly.
The linecount shows how much this simplifies, but to really bring it
home, here's an strace analysis of single Guest->Host ping before:
* Guest sends packet, notifies xmit vq, return control to Launcher
* Launcher clears notification flag on xmit ring
* Launcher writes packet to TUN device
writev(4, [{"\0\0\0\0\0\0\0\0\0\0", 10}, {"\366\r\224`\2058\272m\224vf\274\10\0E\0\0T\0\0@\0@\1\265"..., 98}], 2) = 108
* Launcher sets up interrupt for Guest (xmit ring is empty)
write(10, "\2\0\0\0\3\0\0\0", 8) = 0
* Launcher sets up timer for interrupt mitigation
setitimer(ITIMER_REAL, {it_interval={0, 0}, it_value={0, 505}}, NULL) = 0
* Launcher re-runs guest
pread64(10, 0xbfa5f4d4, 4, 0) ...
* Waker notices reply packet in tun device (it was in select)
select(12, [0 3 4 6 11], NULL, NULL, NULL) = 1 (in [4])
* Waker kicks Launcher out of guest:
pwrite64(10, "\3\0\0\0\1\0\0\0", 8, 0) = 0
* Launcher returns from running guest:
... = -1 EAGAIN (Resource temporarily unavailable)
* Launcher looks at input fds:
select(7, [0 3 4 6], NULL, NULL, {0, 0}) = 1 (in [4], left {0, 0})
* Launcher reads pong from tun device:
readv(4, [{"\0\0\0\0\0\0\0\0\0\0", 10}, {"\272m\224vf\274\366\r\224`\2058\10\0E\0\0T\364\26\0\0@"..., 1518}], 2) = 108
* Launcher injects guest notification:
write(10, "\2\0\0\0\2\0\0\0", 8) = 0
* Launcher rechecks fds:
select(7, [0 3 4 6], NULL, NULL, {0, 0}) = 0 (Timeout)
* Launcher clears Waker:
pwrite64(10, "\3\0\0\0\0\0\0\0", 8, 0) = 0
* Launcher reruns Guest:
pread64(10, 0xbfa5f4d4, 4, 0) = ? ERESTARTSYS (To be restarted)
* Signal comes in, uses pipe to wake up Launcher:
--- SIGALRM (Alarm clock) @ 0 (0) ---
write(8, "\0", 1) = 1
sigreturn() = ? (mask now [])
* Waker sees write on pipe:
select(12, [0 3 4 6 11], NULL, NULL, NULL) = 1 (in [6])
* Waker kicks Launcher out of Guest:
pwrite64(10, "\3\0\0\0\1\0\0\0", 8, 0) = 0
* Launcher exits from kernel:
pread64(10, 0xbfa5f4d4, 4, 0) = -1 EAGAIN (Resource temporarily unavailable)
* Launcher looks to see what fd woke it:
select(7, [0 3 4 6], NULL, NULL, {0, 0}) = 1 (in [6], left {0, 0})
* Launcher reads timeout fd, sets notification flag on xmit ring
read(6, "\0", 32) = 1
* Launcher rechecks fds:
select(7, [0 3 4 6], NULL, NULL, {0, 0}) = 0 (Timeout)
* Launcher clears Waker:
pwrite64(10, "\3\0\0\0\0\0\0\0", 8, 0) = 0
* Launcher resumes Guest:
pread64(10, "\0p\0\4", 4, 0) ....
strace analysis of single Guest->Host ping after:
* Guest sends packet, notifies xmit vq, creates event on eventfd.
* Network xmit thread wakes from read on eventfd:
read(7, "\1\0\0\0\0\0\0\0", 8) = 8
* Network xmit thread writes packet to TUN device
writev(4, [{"\0\0\0\0\0\0\0\0\0\0", 10}, {"J\217\232FI\37j\27\375\276\0\304\10\0E\0\0T\0\0@\0@\1\265"..., 98}], 2) = 108
* Network recv thread wakes up from read on tunfd:
readv(4, [{"\0\0\0\0\0\0\0\0\0\0", 10}, {"j\27\375\276\0\304J\217\232FI\37\10\0E\0\0TiO\0\0@\1\214"..., 1518}], 2) = 108
* Network recv thread sets up interrupt for the Guest
write(6, "\2\0\0\0\2\0\0\0", 8) = 0
* Network recv thread goes back to reading tunfd
13:39:42.460285 readv(4, <unfinished ...>
* Network xmit thread sets up interrupt for Guest (xmit ring is empty)
write(6, "\2\0\0\0\3\0\0\0", 8) = 0
* Network xmit thread goes back to reading from eventfd
read(7, <unfinished ...>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This version requires that host and guest have the same PAE status.
NX cap is not offered to the guest, yet.
Signed-off-by: Matias Zabaljauregui <zabaljauregui@gmail.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
The "len" field in the used ring for virtio indicates the number of
bytes *written* to the buffer. This means the guest doesn't have to
zero the buffers in advance as it always knows the used length.
Erroneously, the console and network example code puts the length
*read* into that field. The guest ignores it, but it's wrong.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
18 months ago 5bbf89fc26 changed to loading
bzImages directly, and no longer manually ungzipping them, so we no longer
need libz.
Also, -m32 is useful for those on 64-bit platforms (and harmless on
32-bit).
Reported-by: Ron Minnich <rminnich@gmail.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2088761152 (lguest: notify on empty) introduced
lguest support for the VIRTIO_F_NOTIFY_ON_EMPTY flag, but in fact it turned on
interrupts all the time.
Because we always process one buffer at a time, the inflight count is always 0
when call trigger_irq and so we always ignore VRING_AVAIL_F_NO_INTERRUPT from
the Guest.
It should be looking to see if there are more buffers in the Guest's queue:
if it's empty, then we force an interrupt.
This makes little difference, since we usually have an empty queue; but
that's the subject of another patch.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Since the Launcher process runs the Guest, it doesn't have to be very
serious about its barriers: the Guest isn't running while we are (Guest
is UP).
Before we change to use threads to service devices, we need to fix this.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We hand the /dev/lguest fd everywhere; it's far neater to just make it
a global (it already is, in fact, hidden in the waker_fds struct).
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We can't trust the values in the device descriptor table once the
guest has booted, so keep local copies. They could set them to
strange values then cause us to segv (they're 8 bit values, so they
can't make our pointers go too wild).
This becomes more important with the following patches which read them.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Commit b00055aacd " [NET] core: add
RFC2863 operstate" defined new interface flag values. Its
documentation specified that these flags could be accessed from user
space via SIOCGIFFLAGS. However, this does not work because the new
flags do not fit in that ioctl's argument width.
Change the documentation to match the code's behavior. Also change
the source to explicitly show the truncation. This _should_ have no
effect on executable code, and did not with gcc 4.2.4 generating x86
code.
A new ioctl could be defined to return all interface flags to user
space. However, since this has been broken for three years with no
one complaining, there doesn't seem much need. They are still
accessible via netlink.
Reported-by: "Fredrik Arnerup" <fredrik.arnerup@edgeware.tv>
Signed-off-by: John Dykstra <john.dykstra1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds the Documentation/kmemleak.txt file with some
information about how kmemleak works.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
This patch introduces three boot options (no_cmci, dont_log_ce
and ignore_ce) to control handling for corrected errors.
The "mce=no_cmci" boot option disables the CMCI feature.
Since CMCI is a new feature so having boot controls to disable
it will be a help if the hardware is misbehaving.
The "mce=dont_log_ce" boot option disables logging for corrected
errors. All reported corrected errors will be cleared silently.
This option will be useful if you never care about corrected
errors.
The "mce=ignore_ce" boot option disables features for corrected
errors, i.e. polling timer and cmci. All corrected events are
not cleared and kept in bank MSRs.
Usually this disablement is not recommended, however it will be
a help if there are some conflict with the BIOS or hardware
monitoring applications etc., that clears corrected events in
banks instead of OS.
[ And trivial cleanup (space -> tab) for doc is included. ]
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
LKML-Reference: <4A30ACDF.5030408@jp.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The function graph tracer is called just "function_graph" (no trailing
"_tracer" needed).
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
LKML-Reference: <1244623722-6325-1-git-send-email-vapier@gentoo.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
All the KCONFIG_ environment variables were previously located in a
section "Environment variables in 'menuconfig'", but neither are they
restricted to 'menuconfig' nor are they all used by 'menuconfig'.
Introduce the following three sections for these variables:
* Environment variables for '*config'
* Environment variables for '{allyes/allmod/allno/rand}config'
* Environment variables for 'silentoldconfig'
Furthermore this puts MENUCONFIG_MODE next to MENUCONFIG_COLOR into a
common section "User interface options for 'menuconfig'".
Signed-off-by: Markus Heidelberg <markus.heidelberg@web.de>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
There is an error in the make syntax for one of the kbuild examples
Signed-off-by: David VomLehn <dvomlehn@cisco.com>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Add MAINTAINERS entry and a small text describing our stack interfaces,
how to hook the drivers, etc.
Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Signed-off-by: Sergey Lapin <slapin@ossfans.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Added 7.1 support for MSI GX620 and jack quirk.
Reference: kernel bug#13430
http://bugzilla.kernel.org/show_bug.cgi?id=13430
Signed-off-by: David Heidelberger <d.okias@gmail.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Clarify calling context and return codes of callback methods, and
add a description of the _cmsg structure and helper functions.
Impact: documentation
Signed-off-by: Tilman Schmidt <tilman@imap.cc>
Signed-off-by: David S. Miller <davem@davemloft.net>
Change the name of the Kernel CAPI exported function capi_ctr_reseted()
to something representing its purpose better.
Impact: renaming, no functional change
Signed-off-by: Tilman Schmidt <tilman@imap.cc>
Signed-off-by: David S. Miller <davem@davemloft.net>
From the perspective of most users of recent systems, disabling Host
Protected Area (HPA) can break vendor RAID formats, GPT partitions and
risks corrupting firmware or overwriting vendor system recovery tools.
Unfortunately the original (kernels < 2.6.30) behavior (unconditionally
disabling HPA and using full disk capacity) was introduced at the time
when the main use of HPA was to make the drive look small enough for the
BIOS to allow the system to boot with large capacity drives.
Thus to allow the maximum compatibility with the existing setups (using
HPA and partitioned with HPA disabled) we automically disable HPA if
any partitions overlapping HPA are detected. Additionally HPA can also
be disabled using the "nohpa" module parameter (i.e. "ide_core.nohpa=0.0"
to disable HPA on /dev/hda).
v2:
Fix ->resume HPA support.
While at it:
- remove stale "idebus=" entry from Documentation/kernel-parameters.txt
Cc: Robert Hancock <hancockrwd@gmail.com>
Cc: Frans Pop <elendil@planet.nl>
Cc: "Andries E. Brouwer" <Andries.Brouwer@cwi.nl>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
[patch description was based on input from Alan Cox and Frans Pop]
Emphatically-Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Several people have suggested that 'perf' has become a full-fledged
tool that should be moved out of Documentation/. Move it to the
(new) tools/ directory.
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Prepare for the 'perf annotate' implementation by splitting off
builtin-annotate.c from builtin-report.c.
( We keep this commit separate to ease the later librarization
of the facilities that perf-report and perf-annotate shares. )
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Mel Gorman