17 Jan, 2012
1 commit
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Since a32618d2 (ARM: pgtable: switch to use pgtable-nopud.h), assabet
warns as follows:arch/arm/mach-sa1100/assabet.c: In function 'map_sa1100_gpio_regs':
arch/arm/mach-sa1100/assabet.c:264: warning: passing argument 1 of 'pmd_offset' from incompatible pointer typeFix this by adding the necessary pud_offset() macro.
Signed-off-by: Russell King
13 Jan, 2012
39 commits
-
Several platforms are now using the memblock_alloc+memblock_free+
memblock_remove trick to obtain memory which won't be mapped in the
kernel's page tables. Most platforms do this (correctly) in the
->reserve callback. However, OMAP has started to call these functions
outside of this callback, and this is extremely unsafe - memory will
not be unmapped, and could well be given out after memblock is no
longer responsible for its management.So, provide arm_memblock_steal() to perform this function, and ensure
that it panic()s if it is used inappropriately. Convert everyone
over, including OMAP.As a result, OMAP with OMAP4_ERRATA_I688 enabled will panic on boot
with this change. Mark this option as BROKEN and make it depend on
BROKEN. OMAP needs to be fixed, or 137d105d50 (ARM: OMAP4: Fix
errata i688 with MPU interconnect barriers.) reverted until such
time it can be fixed correctly.Signed-off-by: Russell King
-
This patch adds a check for the presence of the LPAE feature during the
CPU initialisation. If not present, it reports an error when
CONFIG_DEBUG_LL is enabled.Signed-off-by: Catalin Marinas
Acked-by: Nicolas Pitre
Signed-off-by: Russell King -
This change ensures the platform device name matches nuc900-ac97 platform
driver name.Signed-off-by: Axel Lin
Acked-by: Wan Zongshun
Signed-off-by: Russell King -
Andrew explains:
- various misc stuff
- Most of the rest of MM: memcg, threaded hugepages, others.
- cpumask
- kexec
- kdump
- some direct-io performance tweaking
- radix-tree optimisations
- new selftests code
A note on this: often people will develop a new userspace-visible
feature and will develop userspace code to exercise/test that
feature. Then they merge the patch and the selftest code dies.
Sometimes we paste it into the changelog. Sometimes the code gets
thrown into Documentation/(!).This saddens me. So this patch creates a bare-bones framework which
will henceforth allow me to ask people to include their test apps in
the kernel tree so we can keep them alive. Then when people enhance
or fix the feature, I can ask them to update the test app too.The infrastruture is terribly trivial at present - let's see how it
evolves.- checkpoint/restart feature work.
A note on this: this is a project by various mad Russians to perform
c/r mainly from userspace, with various oddball helper code added
into the kernel where the need is demonstrated.So rather than some large central lump of code, what we have is
little bits and pieces popping up in various places which either
expose something new or which permit something which is normally
kernel-private to be modified.The overall project is an ongoing thing. I've judged that the size
and scope of the thing means that we're more likely to be successful
with it if we integrate the support into mainline piecemeal rather
than allowing it all to develop out-of-tree.However I'm less confident than the developers that it will all
eventually work! So what I'm asking them to do is to wrap each piece
of new code inside CONFIG_CHECKPOINT_RESTORE. So if it all
eventually comes to tears and the project as a whole fails, it should
be a simple matter to go through and delete all trace of it.This lot pretty much wraps up the -rc1 merge for me.
* akpm: (96 commits)
unlzo: fix input buffer free
ramoops: update parameters only after successful init
ramoops: fix use of rounddown_pow_of_two()
c/r: prctl: add PR_SET_MM codes to set up mm_struct entries
c/r: procfs: add start_data, end_data, start_brk members to /proc/$pid/stat v4
c/r: introduce CHECKPOINT_RESTORE symbol
selftests: new x86 breakpoints selftest
selftests: new very basic kernel selftests directory
radix_tree: take radix_tree_path off stack
radix_tree: remove radix_tree_indirect_to_ptr()
dio: optimize cache misses in the submission path
vfs: cache request_queue in struct block_device
fs/direct-io.c: calculate fs_count correctly in get_more_blocks()
drivers/parport/parport_pc.c: fix warnings
panic: don't print redundant backtraces on oops
sysctl: add the kernel.ns_last_pid control
kdump: add udev events for memory online/offline
include/linux/crash_dump.h needs elf.h
kdump: fix crash_kexec()/smp_send_stop() race in panic()
kdump: crashk_res init check for /sys/kernel/kexec_crash_size
... -
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (69 commits)
pptp: Accept packet with seq zero
RDS: Remove some unused iWARP code
net: fsl: fec: handle 10Mbps speed in RMII mode
drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c: add missing iounmap
drivers/net/ethernet/tundra/tsi108_eth.c: add missing iounmap
ksz884x: fix mtu for VLAN
net_sched: sfq: add optional RED on top of SFQ
dp83640: Fix NOHZ local_softirq_pending 08 warning
gianfar: Fix invalid TX frames returned on error queue when time stamping
gianfar: Fix missing sock reference when processing TX time stamps
phylib: introduce mdiobus_alloc_size()
net: decrement memcg jump label when limit, not usage, is changed
net: reintroduce missing rcu_assign_pointer() calls
inet_diag: Rename inet_diag_req_compat into inet_diag_req
inet_diag: Rename inet_diag_req into inet_diag_req_v2
bond_alb: don't disable softirq under bond_alb_xmit
mac80211: fix rx->key NULL pointer dereference in promiscuous mode
nl80211: fix old station flags compatibility
mdio-octeon: use an unique MDIO bus name.
mdio-gpio: use an unique MDIO bus name.
... -
unlzo modifies the pointer to in_buf, so we have to free the original
buffer, not the modified pointer.Signed-off-by: Sascha Hauer
Cc: Lasse Collin
Cc: Namhyung Kim
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
If a platform device exists on the system, but ramoops fails to attach to
it, the module parameters are overridden before ramoops can fall back and
try to use passed module parameters. Move update to end of init routine.Signed-off-by: Kees Cook
Cc: Marco Stornelli
Cc: Sergiu Iordache
Cc: Seiji Aguchi
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
The return value of rounddown_pow_of_two wasn't evaluated, so the
operation was a no-op.Signed-off-by: Marco Stornelli
Reported-by: Andrew Morton
Reviewed-by: WANG Cong
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
When we restore a task we need to set up text, data and data heap sizes
from userspace to the values a task had at checkpoint time. This patch
adds auxilary prctl codes for that.While most of them have a statistical nature (their values are involved
into calculation of /proc//statm output) the start_brk and brk values
are used to compute an allowed size of program data segment expansion.
Which means an arbitrary changes of this values might be dangerous
operation. So to restrict access the following requirements applied to
prctl calls:- The process has to have CAP_SYS_ADMIN capability granted.
- For all opcodes except start_brk/brk members an appropriate
VMA area must exist and should fit certain VMA flags,
such as:
- code segment must be executable but not writable;
- data segment must not be executable.start_brk/brk values must not intersect with data segment and must not
exceed RLIMIT_DATA resource limit.Still the main guard is CAP_SYS_ADMIN capability check.
Note the kernel should be compiled with CONFIG_CHECKPOINT_RESTORE support
otherwise these prctl calls will return -EINVAL.[akpm@linux-foundation.org: cache current->mm in a local, saving 200 bytes text]
Signed-off-by: Cyrill Gorcunov
Reviewed-by: Kees Cook
Cc: Tejun Heo
Cc: Andrew Vagin
Cc: Serge Hallyn
Cc: Pavel Emelyanov
Cc: Vasiliy Kulikov
Cc: KAMEZAWA Hiroyuki
Cc: Michael Kerrisk
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
The mm->start_code/end_code, mm->start_data/end_data, mm->start_brk are
involved into calculation of program text/data segment sizes (which might
be seen in /proc//statm) and into brk() call final address.For restore we need to know all these values. While
mm->start_code/end_code already present in /proc/$pid/stat, the rest
members are not, so this patch brings them in.The restore procedure of these members is addressed in another patch using
prctl().Signed-off-by: Cyrill Gorcunov
Acked-by: Serge Hallyn
Reviewed-by: Kees Cook
Reviewed-by: KAMEZAWA Hiroyuki
Cc: Alexey Dobriyan
Cc: Tejun Heo
Cc: Andrew Vagin
Cc: Vasiliy Kulikov
Cc: Alexey Dobriyan
Cc: "Eric W. Biederman"
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
For checkpoint/restore we need auxilary features being compiled into the
kernel, such as additional prctl codes, /proc//map_files and etc...
but same time these features are not mandatory for a regular kernel so
CHECKPOINT_RESTORE config symbol should bring a way to disable them all at
once if one wish to get rid of additional functionality.Signed-off-by: Cyrill Gorcunov
Cc: Tejun Heo
Cc: Andrew Vagin
Cc: Serge Hallyn
Cc: Vasiliy Kulikov
Reviewed-by: Kees Cook
Cc: KAMEZAWA Hiroyuki
Cc: Alexey Dobriyan
Cc: "Eric W. Biederman"
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Bring a first selftest in the relevant directory. This tests several
combinations of breakpoints and watchpoints in x86, as well as icebp traps
and int3 traps. Given the amount of breakpoint regressions we raised
after we merged the generic breakpoint infrastructure, such selftest
became necessary and can still serve today as a basis for new patches that
touch the do_debug() path.Signed-off-by: Frederic Weisbecker
Cc: Thomas Gleixner
Cc: Ingo Molnar
Cc: H. Peter Anvin
Cc: Jason Wessel
Cc: Will Deacon
Cc: Michal Marek
Cc: Sam Ravnborg
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Bring a new kernel selftests directory in tools/testing/selftests. To
add a new selftest, create a subdirectory with the sources and a
makefile that creates a target named "run_test" then add the
subdirectory name to the TARGET var in tools/testing/selftests/Makefile
and tools/testing/selftests/run_tests script.This can help centralizing and maintaining any useful selftest that
developers usually tend to let rust in peace on some random server.Suggested-by: Andrew Morton
Signed-off-by: Frederic Weisbecker
Cc: Thomas Gleixner
Cc: Ingo Molnar
Cc: "H. Peter Anvin"
Cc: Jason Wessel
Cc: Will Deacon
Cc: Steven Rostedt
Cc: Michal Marek
Cc: Sam Ravnborg
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Down, down in the deepest depths of GFP_NOIO page reclaim, we have
shrink_page_list() calling __remove_mapping() calling __delete_from_
swap_cache() or __delete_from_page_cache().You would not expect those to need much stack, but in fact they call
radix_tree_delete(): which declares a 192-byte radix_tree_path array on
its stack (to record the node,offsets it visits when descending, in case
it needs to ascend to update them). And if any tag is still set [1],
that calls radix_tree_tag_clear(), which declares a further such
192-byte radix_tree_path array on the stack. (At least we have
interrupts disabled here, so won't then be pushing registers too.)That was probably a good choice when most users were 32-bit (array of
half the size), and adding fields to radix_tree_node would have bloated
it unnecessarily. But nowadays many are 64-bit, and each
radix_tree_node contains a struct rcu_head, which is only used when
freeing; whereas the radix_tree_path info is only used for updating the
tree (deleting, clearing tags or setting tags if tagged) when a lock
must be held, of no interest when accessing the tree locklessly.So add a parent pointer to the radix_tree_node, in union with the
rcu_head, and remove all uses of the radix_tree_path. There would be
space in that union to save the offset when descending as before (we can
argue that a lock must already be held to exclude other users), but
recalculating it when ascending is both easy (a constant shift and a
constant mask) and uncommon, so it seems better just to do that.Two little optimizations: no need to decrement height when descending,
adjusting shift is enough; and once radix_tree_tag_if_tagged() has set
tag on a node and its ancestors, it need not ascend from that node
again.perf on the radix tree test harness reports radix_tree_insert() as 2%
slower (now having to set parent), but radix_tree_delete() 24% faster.
Surely that's an exaggeration from rtth's artificially low map shift 3,
but forcing it back to 6 still rates radix_tree_delete() 8% faster.[1] Can a pagecache tag (dirty, writeback or towrite) actually still be
set at the time of radix_tree_delete()? Perhaps not if the filesystem is
well-behaved. But although I've not tracked any stack overflow down to
this cause, I have observed a curious case in which a dirty tag is set
and left set on tmpfs: page migration's migrate_page_copy() happens to
use __set_page_dirty_nobuffers() to set PageDirty on the newpage, and
that sets PAGECACHE_TAG_DIRTY as a side-effect - harmless to a
filesystem which doesn't use tags, except for this stack depth issue.Signed-off-by: Hugh Dickins
Cc: Jan Kara
Cc: Dave Chinner
Cc: Mel Gorman
Cc: Nai Xia
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
It is not used anymore, remove it
Signed-off-by: Xiao Guangrong
Acked-by: Hugh Dickins
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Some investigation of a transaction processing workload showed that a
major consumer of cycles in __blockdev_direct_IO is the cache miss while
accessing the block size. This is because it has to walk the chain from
block_dev to gendisk to queue.The block size is needed early on to check alignment and sizes. It's only
done if the check for the inode block size fails. But the costly block
device state is unconditionally fetched.- Reorganize the code to only fetch block dev state when actually
needed.Then do a prefetch on the block dev early on in the direct IO path. This
is worth it, because there is substantial code run before we actually
touch the block dev now.- I also added some unlikelies to make it clear the compiler that block
device fetch code is not normally executed.This gave a small, but measurable improvement on a large database
benchmark (about 0.3%)[akpm@linux-foundation.org: coding-style fixes]
[sfr@canb.auug.org.au: using prefetch requires including prefetch.h]
Signed-off-by: Andi Kleen
Cc: Jeff Moyer
Cc: Jens Axboe
Cc: Christoph Hellwig
Signed-off-by: Stephen Rothwell
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
This makes it possible to get from the inode to the request_queue with one
less cache miss. Used in followon optimization.The livetime of the pointer is the same as the gendisk.
This assumes that the queue will always stay the same in the gendisk while
it's visible to block_devices. I think that's safe correct?Signed-off-by: Andi Kleen
Acked-by: Jeff Moyer
Cc: Jens Axboe
Cc: Christoph Hellwig
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
In get_more_blocks(), we use dio_count to calcuate fs_count and do some
tricky things to increase fs_count if dio_count isn't aligned. But
actually it still has some corner cases that can't be coverd. See the
following example:dio_write foo -s 1024 -w 4096
(direct write 4096 bytes at offset 1024). The same goes if the offset
isn't aligned to fs_blocksize.In this case, the old calculation counts fs_count to be 1, but actually we
will write into 2 different blocks (if fs_blocksize=4096). The old code
just works, since it will call get_block twice (and may have to allocate
and create extents twice for filesystems like ext4). So we'd better call
get_block just once with the proper fs_count.Signed-off-by: Tao Ma
Cc: "Theodore Ts'o"
Cc: Christoph Hellwig
Cc: Al Viro
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
drivers/parport/parport_pc.c: In function '__check_irq':
drivers/parport/parport_pc.c:3415: warning: return from incompatible pointer type
drivers/parport/parport_pc.c: In function '__check_dma':
drivers/parport/parport_pc.c:3417: warning: return from incompatible pointer typeSigned-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
When an oops causes a panic and panic prints another backtrace it's pretty
common to have the original oops data be scrolled away on a 80x50 screen.The second backtrace is quite redundant and not needed anyways.
So don't print the panic backtrace when oops_in_progress is true.
[akpm@linux-foundation.org: add comment]
Signed-off-by: Andi Kleen
Cc: Michael Holzheu
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
The sysctl works on the current task's pid namespace, getting and setting
its last_pid field.Writing is allowed for CAP_SYS_ADMIN-capable tasks thus making it possible
to create a task with desired pid value. This ability is required badly
for the checkpoint/restore in userspace.This approach suits all the parties for now.
Signed-off-by: Pavel Emelyanov
Acked-by: Tejun Heo
Cc: Oleg Nesterov
Cc: Cyrill Gorcunov
Cc: "Eric W. Biederman"
Cc: Serge Hallyn
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Currently no udev events for memory hotplug "online" and "offline" are
generated:# udevadm monitor
# echo offline > /sys/devices/system/memory/memory4/state
==> No eventWhen kdump is loaded, kexec detects the current memory configuration and
stores it in the pre-allocated ELF core header. Therefore, for kdump it
is necessary to reload the kdump kernel with kexec when the memory
configuration changes (e.g. for online/offline hotplug memory).In order to do this automatically, udev rules should be used. This kernel
patch adds udev events for "online" and "offline". Together with this
kernel patch, the following udev rules for online/offline have to be added
to "/etc/udev/rules.d/98-kexec.rules":SUBSYSTEM=="memory", ACTION=="online", PROGRAM="/etc/init.d/kdump restart"
SUBSYSTEM=="memory", ACTION=="offline", PROGRAM="/etc/init.d/kdump restart"[sfr@canb.auug.org.au: fixups for class to subsystem conversion]
Signed-off-by: Michael Holzheu
Cc: Heiko Carstens
Cc: Vivek Goyal
Cc: "Eric W. Biederman"
Cc: Kay Sievers
Cc: Dave Hansen
Cc: Martin Schwidefsky
Cc: Greg KH
Signed-off-by: Stephen Rothwell
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Building an ARM target we get the following warnings:
CC arch/arm/kernel/setup.o
In file included from arch/arm/kernel/setup.c:39:
arch/arm/include/asm/elf.h:102:1: warning: "vmcore_elf64_check_arch" redefined
In file included from arch/arm/kernel/setup.c:24:
include/linux/crash_dump.h:30:1: warning: this is the location of the previous definitionQuoting Russell King:
"linux/crash_dump.h makes no attempt to include asm/elf.h, but it depends
on stuff in asm/elf.h to determine how stuff inside this file is defined
at parse time.So, if asm/elf.h is included after linux/crash_dump.h or not at all, you
get a different result from the situation where asm/elf.h is included
before."So add elf.h header to crash_dump.h to avoid this problem.
The original discussion about this can be found at:
http://www.spinics.net/lists/arm-kernel/msg154113.htmlSigned-off-by: Fabio Estevam
Cc: Russell King
Cc: [3.2.1]
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
When two CPUs call panic at the same time there is a possible race
condition that can stop kdump. The first CPU calls crash_kexec() and the
second CPU calls smp_send_stop() in panic() before crash_kexec() finished
on the first CPU. So the second CPU stops the first CPU and therefore
kdump fails:1st CPU:
panic()->crash_kexec()->mutex_trylock(&kexec_mutex)-> do kdump2nd CPU:
panic()->crash_kexec()->kexec_mutex already held by 1st CPU
->smp_send_stop()-> stop 1st CPU (stop kdump)This patch fixes the problem by introducing a spinlock in panic that
allows only one CPU to process crash_kexec() and the subsequent panic
code.All other CPUs call the weak function panic_smp_self_stop() that stops the
CPU itself. This function can be overloaded by architecture code. For
example "tile" can use their lower-power "nap" instruction for that.Signed-off-by: Michael Holzheu
Acked-by: Chris Metcalf
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Currently it is possible to set the crash_size via the sysfs
/sys/kernel/kexec_crash_size even if no crash kernel memory has been
defined with the "crashkernel" parameter. In this case "crashk_res" is
not initialized and crashk_res.start = crashk_res.end = 0. Unfortunately
resource_size(&crashk_res) returns 1 in this case. This breaks the s390
implementation of crash_(un)map_reserved_pages().To fix the problem the correct "old_size" is now calculated in
crash_shrink_memory(). "old_size is set to "0" if crashk_res is not
initialized. With this change crash_shrink_memory() will do nothing, when
"crashk_res" is not initialized. It will return "0" for "echo 0 >
/sys/kernel/kexec_crash_size" and -EINVAL for "echo [not zero] >
/sys/kernel/kexec_crash_size".In addition to that this patch also simplifies the "ret = -EINVAL" vs.
"ret = 0" logic as suggested by Simon Horman.Signed-off-by: Michael Holzheu
Reviewed-by: Dave Young
Reviewed-by: WANG Cong
Reviewed-by: Simon Horman
Cc: Vivek Goyal
Cc: "Eric W. Biederman"
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
When shrinking crashkernel memory using /sys/kernel/kexec_crash_size for
the newly added memory no RAM resource is created at the moment.Example:
$ cat /proc/iomem
00000000-bfffffff : System RAM
00000000-005b7ac3 : Kernel code
005b7ac4-009743bf : Kernel data
009bb000-00a85c33 : Kernel bss
c0000000-cfffffff : Crash kernel
d0000000-ffffffff : System RAM$ echo 0 > /sys/kernel/kexec_crash_size
$ cat /proc/iomem
00000000-bfffffff : System RAM
00000000-005b7ac3 : Kernel code
005b7ac4-009743bf : Kernel data
009bb000-00a85c33 : Kernel bss
< /sys/kernel/kexec_crash_size
$ cat /proc/iomem
00000000-bfffffff : System RAM
00000000-005b7ac3 : Kernel code
005b7ac4-009743bf : Kernel data
009bb000-00a85c33 : Kernel bss
c0000000-cfffffff : System RAM <
Cc: Vivek Goyal
Cc: "Eric W. Biederman"
Cc: Heiko Carstens
Cc: Martin Schwidefsky
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
KMSG_DUMP_KEXEC is useless because we already save kernel messages inside
/proc/vmcore, and it is unsafe to allow modules to do other stuffs in a
crash dump scenario.[akpm@linux-foundation.org: fix powerpc build]
Signed-off-by: WANG Cong
Reported-by: Vivek Goyal
Acked-by: Vivek Goyal
Acked-by: Jarod Wilson
Cc: "Eric W. Biederman"
Cc: KOSAKI Motohiro
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
node_to_cpumask() has been replaced by cpumask_of_node(), and wholly
removed since commit 29c337a0 ("cpumask: remove obsolete node_to_cpumask
now everyone uses cpumask_of_node").So update the comments for setup_node_to_cpumask_map().
Signed-off-by: Wanlong Gao
Acked-by: Rusty Russell
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
If either of the vas or vms arrays are not properly kzalloced, then the
code jumps to the err_free label.The err_free label runs a loop to check and free each of the array members
of the vas and vms arrays which is not required for this situation as none
of the array members have been allocated till this point.Eliminate the extra loop we have to go through by introducing a new label
err_free2 and then jumping to it.[akpm@linux-foundation.org: remove now-unneeded tests]
Signed-off-by: Kautuk Consul
Acked-by: David Rientjes
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
There is sometimes confusion between the global putback_lru_pages() in
migrate.c and the static putback_lru_pages() in vmscan.c: rename the
latter putback_inactive_pages(): it helps shrink_inactive_list() rather as
move_active_pages_to_lru() helps shrink_active_list().Remove unused scan_control arg from putback_inactive_pages() and from
update_isolated_counts(). Move clear_active_flags() inside
update_isolated_counts(). Move NR_ISOLATED accounting up into
shrink_inactive_list() itself, so the balance is clearer.Do the spin_lock_irq() before calling putback_inactive_pages() and
spin_unlock_irq() after return from it, so that it better matches
update_isolated_counts() and move_active_pages_to_lru().Signed-off-by: Hugh Dickins
Cc: Johannes Weiner
Cc: KOSAKI Motohiro
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
The isolate_pages() level in vmscan.c offers little but indirection: merge
it into isolate_lru_pages() as the compiler does, and use the names
nr_to_scan and nr_scanned in each case.Signed-off-by: Hugh Dickins
Reviewed-by: KOSAKI Motohiro
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
del_page_from_lru() repeats del_page_from_lru_list(), also working out
which LRU the page was on, clearing the relevant bits. Decouple those
functions: remove del_page_from_lru() and add page_off_lru().Signed-off-by: Hugh Dickins
Reviewed-by: KOSAKI Motohiro
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Mostly we use "enum lru_list lru": change those few "l"s to "lru"s.
Signed-off-by: Hugh Dickins
Reviewed-by: KOSAKI Motohiro
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
checkpatch rightly protests
WARNING: EXPORT_SYMBOL(foo); should immediately follow its function/variable
so fix the five offenders in mm/swap.c.
Signed-off-by: Hugh Dickins
Reviewed-by: KOSAKI Motohiro
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
What's so special about ____pagevec_lru_add() that it needs four leading
underscores? Nothing, it just helped to distinguish from
__pagevec_lru_add() in 2.6.28 development. Cut two leading underscores.Signed-off-by: Hugh Dickins
Reviewed-by: KOSAKI Motohiro
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Replace pagevecs in putback_lru_pages() and move_active_pages_to_lru()
by lists of pages_to_free: then apply Konstantin Khlebnikov's
free_hot_cold_page_list() to them instead of pagevec_release().Which simplifies the flow (no need to drop and retake lock whenever
pagevec fills up) and reduces stale addresses in stack backtraces
(which often showed through the pagevecs); but more importantly,
removes another 120 bytes from the deepest stacks in page reclaim.
Although I've not recently seen an actual stack overflow here with
a vanilla kernel, move_active_pages_to_lru() has often featured in
deep backtraces.However, free_hot_cold_page_list() does not handle compound pages
(nor need it: a Transparent HugePage would have been split by the
time it reaches the call in shrink_page_list()), but it is possible
for putback_lru_pages() or move_active_pages_to_lru() to be left
holding the last reference on a THP, so must exclude the unlikely
compound case before putting on pages_to_free.Remove pagevec_strip(), its work now done in move_active_pages_to_lru().
The pagevec in scan_mapping_unevictable_pages() remains in mm/vmscan.c,
but that is never on the reclaim path, and cannot be replaced by a list.Signed-off-by: Hugh Dickins
Reviewed-by: KOSAKI Motohiro
Reviewed-by: Konstantin Khlebnikov
Cc: KAMEZAWA Hiroyuki
Cc: Mel Gorman
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
If DEBUG_VM, mem_cgroup_print_bad_page() is called whenever bad_page()
shows a "Bad page state" message, removes page from circulation, adds a
taint and continues. This is at a very low level, often when a spinlock
is held (sometimes when page table lock is held, for example).We want to recover from this badness, not make it worse: we must not
kmalloc memory here, we must not do a cgroup path lookup via dubious
pointers. No doubt that code was useful to debug a particular case at one
time, and may be again, but take it out of the mainline kernel.Signed-off-by: Hugh Dickins
Cc: Daisuke Nishimura
Cc: KAMEZAWA Hiroyuki
Cc: Johannes Weiner
Cc: Michal Hocko
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
This patch started off as a cleanup: __split_huge_page_refcounts() has to
cope with two scenarios, when the hugepage being split is already on LRU,
and when it is not; but why does it have to split that accounting across
three different sites? Consolidate it in lru_add_page_tail(), handling
evictable and unevictable alike, and use standard add_page_to_lru_list()
when accounting is needed (when the head is not yet on LRU).But a recent regression in -next, I guess the removal of PageCgroupAcctLRU
test from mem_cgroup_split_huge_fixup(), makes this now a necessary fix:
under load, the MEM_CGROUP_ZSTAT count was wrapping to a huge number,
messing up reclaim calculations and causing a freeze at rmdir of cgroup.Add a VM_BUG_ON to mem_cgroup_lru_del_list() when we're about to wrap that
count - this has not been the only such incident. Document that
lru_add_page_tail() is for Transparent HugePages by #ifdef around it.Signed-off-by: Hugh Dickins
Cc: Daisuke Nishimura
Cc: KAMEZAWA Hiroyuki
Cc: Johannes Weiner
Cc: Michal Hocko
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
