Wang Weidong says:
====================
sctp: remove some macro locking wrappers
In sctp.h we can find some macro locking wrappers. As Neil point out that:
"Its because in the origional implementation of the sctp protocol, there was a
user space test harness which built the kernel module for userspace execution to
cary our some unit testing on the code. It did so by redefining some of those
locking macros to user space friendly code. IIRC we haven't use those unit
tests in years, and so should be removing them, not adding them to other
locations."
So I remove them.
====================
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Redefined bh_[un]lock_sock to sctp_bh[un]lock_sock for user
space friendly code which we haven't use in years, so removing them.
Signed-off-by: Wang Weidong <wangweidong1@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Redefined {lock|release}_sock to sctp_{lock|release}_sock for user space friendly
code which we haven't use in years, so removing them.
Signed-off-by: Wang Weidong <wangweidong1@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Redefined read_[un]lock to sctp_read_[un]lock for user space
friendly code which we haven't use in years, and the macros
we never used, so removing them.
Signed-off-by: Wang Weidong <wangweidong1@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Redefined write_[un]lock to sctp_write_[un]lock for user space
friendly code which we haven't use in years, so removing them.
Signed-off-by: Wang Weidong <wangweidong1@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Redefined spin_[un]lock to sctp_spin_[un]lock for user space friendly
code which we haven't use in years, so removing them.
Signed-off-by: Wang Weidong <wangweidong1@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Redefined local_bh_{disable|enable} to sctp_local_bh_{disable|enable}
for user space friendly code which we haven't use in years, so removing them.
Signed-off-by: Wang Weidong <wangweidong1@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Redefined spin_[un]lock_irqstore to sctp_spin_[un]lock_irqrestore for user
space friendly code which we haven't use in years, so removing them.
Signed-off-by: Wang Weidong <wangweidong1@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull libata updates from Tejun Heo:
"Support for some new embedded controllers.
A couple late (<= a week) fixes have stable cc'd and one patch ("SATA:
MV: Add support for the optional PHYs") got committed yesterday
because otherwise the resulting kernel would fail boot on an embedded
board due to interdependent changes in its platform tree.
Other than that, nothing too noteworthy"
* 'for-3.14' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/libata:
SATA: MV: Add support for the optional PHYs
sata-highbank: Remove unnecessary ahci_platform.h include
libata: disable LPM for some WD SATA-I devices
ARM: mvebu: update the SATA compatible string for Armada 370/XP
ata: sata_mv: fix disk hotplug for Armada 370/XP SoCs
ata: sata_mv: introduce compatible string "marvell, armada-370-sata"
ata: pata_samsung_cf: Remove unused macros
ata: pata_samsung_cf: Use devm_ioremap_resource()
ata: pata_samsung_cf: Merge pata_samsung_cf.h into pata_samsung_cf.c
ata: pata_samsung_cf: Move plat/regs-ata.h to drivers/ata
drivers: ata: Mark the function as static in libahci.c
drivers: ata: Mark the function ahci_init_interrupts() as static in ahci.c
ahci: imx: fix the error handling in imx_ahci_probe()
ahci: imx: ahci_imx_softreset() can be static
ahci: imx: Add i.MX53 support
ahci: imx: Pull out the clock enable/disable calls
libata, dt: Document sata_rcar bindings
sata_rcar: Add R-Car Gen2 SATA PHY support
ahci: mcp89: enter AHCI mode under Apple BIOS emulation
ata: libata-eh: Remove unnecessary snprintf arithmetic
Use ether_addr_copy instead of memcpy(a, b, ETH_ALEN) to
save some cycles on arm and powerpc.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use ether_addr_copy instead of memcpy(a, b, ETH_ALEN) to
save some cycles on arm and powerpc.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use ether_addr_copy instead of memcpy(a, b, ETH_ALEN) to
save some cycles on arm and powerpc.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use ether_addr_copy instead of memcpy(a, b, ETH_ALEN) to
save some cycles on arm and powerpc.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use ether_addr_copy instead of memcpy(a, b, ETH_ALEN) to
save some cycles on arm and powerpc.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use ether_addr_copy instead of memcpy(a, b, ETH_ALEN) to
save some cycles on arm and powerpc.
Convert struct aarp_entry.hwaddr[6] to hwaddr[ETH_ALEN].
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use ether_addr_copy instead of memcpy(a, b, ETH_ALEN) to
save some cycles on arm and powerpc.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Or Gerlitz says:
====================
net: Add GRO support for UDP encapsulating protocols
This series adds GRO handlers for protocols that do UDP encapsulation, with the
intent of being able to coalesce packets which encapsulate packets belonging to
the same TCP session.
For GRO purposes, the destination UDP port takes the role of the ether type
field in the ethernet header or the next protocol in the IP header.
The UDP GRO handler will only attempt to coalesce packets whose destination
port is registered to have gro handler.
The patches done against net-next 75e4364f67 "net: stmmac: fix NULL pointer
dereference in stmmac_get_tx_hwtstamp"
Or.
v4 --> v5 changes:
- followed Eric's directives to avoid using atomic get/put ops on the
udp gro receive and complete callbacks and instead keep the rcu_read_lock
when calling the next handler on the chain.
v3 --> v4 changes:
- applied feedback from Tom on some micro-optimizations that save
branches and goto directives in the udp gro logic
- applied feedback from Eric on correct RCU programming for the
add/remove flow of the upper protocols udp gro handlers
v2 --> v3 changes:
- moved to use linked list to store the udp gro handlers, this solves the
problem of consuming 512KB of memory for the handlers.
- use a mark on the skb GRO CB data to disallow running the udp gro_receive twice
on a packet, this solves the problem of udp encapsulated packets whose inner VM
packet is udp and happen to carry a port which has registered offloads - and flush it.
- invoke the udp offload protocol registration and de-registration from the vxlan driver
in a sleepable context
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Export the gro_find_receive/complete_by_type helpers to they can be invoked
by the gro callbacks of encapsulation protocols such as vxlan.
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add GRO handlers for protocols that do UDP encapsulation, with the intent of
being able to coalesce packets which encapsulate packets belonging to
the same TCP session.
For GRO purposes, the destination UDP port takes the role of the ether type
field in the ethernet header or the next protocol in the IP header.
The UDP GRO handler will only attempt to coalesce packets whose destination
port is registered to have gro handler.
Use a mark on the skb GRO CB data to disallow (flush) running the udp gro receive
code twice on a packet. This solves the problem of udp encapsulated packets whose
inner VM packet is udp and happen to carry a port which has registered offloads.
Signed-off-by: Shlomo Pongratz <shlomop@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull cgroup updates from Tejun Heo:
"The bulk of changes are cleanups and preparations for the upcoming
kernfs conversion.
- cgroup_event mechanism which is and will be used only by memcg is
moved to memcg.
- pidlist handling is updated so that it can be served by seq_file.
Also, the list is not sorted if sane_behavior. cgroup
documentation explicitly states that the file is not sorted but it
has been for quite some time.
- All cgroup file handling now happens on top of seq_file. This is
to prepare for kernfs conversion. In addition, all operations are
restructured so that they map 1-1 to kernfs operations.
- Other cleanups and low-pri fixes"
* 'for-3.14' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: (40 commits)
cgroup: trivial style updates
cgroup: remove stray references to css_id
doc: cgroups: Fix typo in doc/cgroups
cgroup: fix fail path in cgroup_load_subsys()
cgroup: fix missing unlock on error in cgroup_load_subsys()
cgroup: remove for_each_root_subsys()
cgroup: implement for_each_css()
cgroup: factor out cgroup_subsys_state creation into create_css()
cgroup: combine css handling loops in cgroup_create()
cgroup: reorder operations in cgroup_create()
cgroup: make for_each_subsys() useable under cgroup_root_mutex
cgroup: css iterations and css_from_dir() are safe under cgroup_mutex
cgroup: unify pidlist and other file handling
cgroup: replace cftype->read_seq_string() with cftype->seq_show()
cgroup: attach cgroup_open_file to all cgroup files
cgroup: generalize cgroup_pidlist_open_file
cgroup: unify read path so that seq_file is always used
cgroup: unify cgroup_write_X64() and cgroup_write_string()
cgroup: remove cftype->read(), ->read_map() and ->write()
hugetlb_cgroup: convert away from cftype->read()
...
Pull percpu changes from Tejun Heo:
"Two trivial changes - addition of WARN_ONCE() in lib/percpu-refcount.c
and use of VMALLOC_TOTAL instead of END - START in percpu.c"
* 'for-3.14' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu:
percpu: use VMALLOC_TOTAL instead of VMALLOC_END - VMALLOC_START
percpu-refcount: Add a WARN() for ref going negative
Pull workqueue update from Tejun Heo:
"Just one patch to add destroy_work_on_stack() annotations to help
debugobj debugging"
* 'for-3.14' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
workqueue: Calling destroy_work_on_stack() to pair with INIT_WORK_ONSTACK()
This set includes a single change to speed up
recovery times when using SCTP connections.
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Merge tag 'dlm-3.14' of git://git.kernel.org/pub/scm/linux/kernel/git/teigland/linux-dlm
Pull dlm update from David Teigland:
"A single change to speed up recovery times when using SCTP
connections"
* tag 'dlm-3.14' of git://git.kernel.org/pub/scm/linux/kernel/git/teigland/linux-dlm:
dlm: set zero linger time on sctp socket
improvements when searching resource groups and several updates
to quotas which should increase scalability. The quota changes
follow on from those in the last merge window, and there will
likely be further work to come in this area in due course.
There are also a few patches which help to improve efficiency
of adding entries into directories, and clean up some of that
code.
One on-disk change is included this time, which is to write some
additional information which should be useful to fsck and
also potentially for debugging.
Other than that, its just a few small random bug fixes and
clean ups.
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Merge tag 'gfs2-merge-window' of git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-3.0-nmw
Pull GFS2 updates from Steven Whitehouse:
"The main topics this time are allocation, in the form of Bob's
improvements when searching resource groups and several updates to
quotas which should increase scalability. The quota changes follow on
from those in the last merge window, and there will likely be further
work to come in this area in due course.
There are also a few patches which help to improve efficiency of
adding entries into directories, and clean up some of that code.
One on-disk change is included this time, which is to write some
additional information which should be useful to fsck and also
potentially for debugging.
Other than that, its just a few small random bug fixes and clean ups"
* tag 'gfs2-merge-window' of git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-3.0-nmw: (24 commits)
GFS2: revert "GFS2: d_splice_alias() can't return error"
GFS2: Small cleanup
GFS2: Don't use ENOBUFS when ENOMEM is the correct error code
GFS2: Fix kbuild test robot reported warning
GFS2: Move quota bitmap operations under their own lock
GFS2: Clean up quota slot allocation
GFS2: Only run logd and quota when mounted read/write
GFS2: Use RCU/hlist_bl based hash for quotas
GFS2: No need to invalidate pages for a dio read
GFS2: Add initialization for address space in super block
GFS2: Add hints to directory leaf blocks
GFS2: For exhash conversion, only one block is needed
GFS2: Increase i_writecount during gfs2_setattr_chown
GFS2: Remember directory insert point
GFS2: Consolidate transaction blocks calculation for dir add
GFS2: Add directory addition info structure
GFS2: Use only a single address space for rgrps
GFS2: Use range based functions for rgrp sync/invalidation
GFS2: Remove test which is always true
GFS2: Remove gfs2_quota_change_host structure
...
This change adds a parameter for the Synopsys 10/100/1000
stmmac Ethernet driver to configure the maximum frame
size supported by the EMAC driver. Synopsys allows the FIFO
sizes to be configured when the cores are built for a particular
device, but do not provide a way for the driver to read
information from the device about the maximum MTU size
supported as limited by the device's FIFO size.
Signed-off-by: Vince Bridgers <vbridgers2013@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Smatch complains because we are using an untrusted index into the
rxrpc_acks[] array. It's just a read and it's only in the debug code,
but it's simple enough to add a check and fix it.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Replace deprecated 'vconfig' tool with 'ip' from 'iproute2'. Add
some beautifications like replacing 'ethernet' with 'Ethernet' and
removing unneeded spaces.
Signed-off-by: Yegor Yefremov <yegorslists@googlemail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Some ipv6 protocols cannot handle ipv4 addresses, so we must not allow
connecting and binding to them. sendmsg logic does already check msg->name
for this but must trust already connected sockets which could be set up
for connection to ipv4 address family.
Per-socket flag ipv6only is of no use here, as it is under users control
by setsockopt.
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
- Uses ipv6_anycast_destination() in icmp6_send().
Suggested-by: Bill Fink <billfink@mindspring.com>
Signed-off-by: Francois-Xavier Le Bail <fx.lebail@yahoo.com>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
As tcp_rcv_state_process() has already calls tcp_mtup_init() for non-fastopen
sock, we can delete the redundant calls of tcp_mtup_init() in
tcp_{v4,v6}_syn_recv_sock().
Signed-off-by: Weiping Pan <panweiping3@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Doesn't bring much, but also doesn't hurt us to fix 'em:
1) In tpacket_rcv() flush dcache page we can restirct the scope
for start and end and remove one layer of indent.
2) In tpacket_destruct_skb() we can restirct the scope for ph.
3) In alloc_one_pg_vec_page() we can remove the NULL assignment
and change spacing a bit.
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Since commit c544193214("GRE: Refactor GRE tunneling code")
introduced function ip_tunnel_hash(), the argument itn is no
longer in use, so remove it.
Signed-off-by: Duan Jiong <duanj.fnst@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
As release_stripe and __release_stripe decrement ->count and then
manipulate ->lru both under ->device_lock, it is important that
get_active_stripe() increments ->count and clears ->lru also under
->device_lock.
However we currently list_del_init ->lru under the lock, but increment
the ->count outside the lock. This can lead to races and list
corruption.
So move the atomic_inc(&sh->count) up inside the ->device_lock
protected region.
Note that we still increment ->count without device lock in the case
where get_free_stripe() was called, and in fact don't take
->device_lock at all in that path.
This is safe because if the stripe_head can be found by
get_free_stripe, then the hash lock assures us the no-one else could
possibly be calling release_stripe() at the same time.
Fixes: 566c09c534
Cc: stable@vger.kernel.org (3.13)
Reported-and-tested-by: Ian Kumlien <ian.kumlien@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
softnet_data is already set to 0, no need to use memset or initialize
specific fields to 0 or NULL afterwards.
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add a description to the vxlan module, helping save the world
from the minions of destruction and confusion.
Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
CC: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Some part of putback_lru_pages() and putback_movable_pages() is
duplicated, so it could confuse us what we should use. We can remove
putback_lru_pages() since it is not really needed now. This makes us
undestand and maintain the code more easily.
And comment on putback_movable_pages() is stale now, so fix it.
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Reviewed-by: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Rafael Aquini <aquini@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We should remove the page from the list if we fail with ENOSYS, since
migrate_pages() consider error cases except -ENOMEM and -EAGAIN as
permanent failure and it assumes that the page would be removed from the
list. Without this patch, we could overcount number of failure.
In addition, we should put back the new hugepage if
!hugepage_migration_support(). If not, we would leak hugepage memory.
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Acked-by: Christoph Lameter <cl@linux.com>
Reviewed-by: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Reviewed-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Rafael Aquini <aquini@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Let's add a comment about where the failed page goes to, which makes
code more readable.
Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Acked-by: Christoph Lameter <cl@linux.com>
Reviewed-by: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Acked-by: Rafael Aquini <aquini@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
__GFP_NOFAIL may return NULL when coupled with GFP_NOWAIT or GFP_ATOMIC.
Luckily, nothing currently does such craziness. So instead of causing
such allocations to loop (potentially forever), we maintain the current
behavior and also warn about the new users of the deprecated flag.
Suggested-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David Rientjes <rientjes@google.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Compaction used to start its migrate and free page scaners at the zone's
lowest and highest pfn, respectively. Later, caching was introduced to
remember the scanners' progress across compaction attempts so that
pageblocks are not re-scanned uselessly. Additionally, pageblocks where
isolation failed are marked to be quickly skipped when encountered again
in future compactions.
Currently, both the reset of cached pfn's and clearing of the pageblock
skip information for a zone is done in __reset_isolation_suitable().
This function gets called when:
- compaction is restarting after being deferred
- compact_blockskip_flush flag is set in compact_finished() when the scanners
meet (and not again cleared when direct compaction succeeds in allocation)
and kswapd acts upon this flag before going to sleep
This behavior is suboptimal for several reasons:
- when direct sync compaction is called after async compaction fails (in the
allocation slowpath), it will effectively do nothing, unless kswapd
happens to process the compact_blockskip_flush flag meanwhile. This is racy
and goes against the purpose of sync compaction to more thoroughly retry
the compaction of a zone where async compaction has failed.
The restart-after-deferring path cannot help here as deferring happens only
after the sync compaction fails. It is also done only for the preferred
zone, while the compaction might be done for a fallback zone.
- the mechanism of marking pageblock to be skipped has little value since the
cached pfn's are reset only together with the pageblock skip flags. This
effectively limits pageblock skip usage to parallel compactions.
This patch changes compact_finished() so that cached pfn's are reset
immediately when the scanners meet. Clearing pageblock skip flags is
unchanged, as well as the other situations where cached pfn's are reset.
This allows the sync-after-async compaction to retry pageblocks not
marked as skipped, such as blocks !MIGRATE_MOVABLE blocks that async
compactions now skips without marking them.
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Rik van Riel <riel@redhat.com>
Acked-by: Mel Gorman <mgorman@suse.de>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Compaction temporarily marks pageblocks where it fails to isolate pages
as to-be-skipped in further compactions, in order to improve efficiency.
One of the reasons to fail isolating pages is that isolation is not
attempted in pageblocks that are not of MIGRATE_MOVABLE (or CMA) type.
The problem is that blocks skipped due to not being MIGRATE_MOVABLE in
async compaction become skipped due to the temporary mark also in future
sync compaction. Moreover, this may follow quite soon during
__alloc_page_slowpath, without much time for kswapd to clear the
pageblock skip marks. This goes against the idea that sync compaction
should try to scan these blocks more thoroughly than the async
compaction.
The fix is to ensure in async compaction that these !MIGRATE_MOVABLE
blocks are not marked to be skipped. Note this should not affect
performance or locking impact of further async compactions, as skipping
a block due to being !MIGRATE_MOVABLE is done soon after skipping a
block marked to be skipped, both without locking.
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Rik van Riel <riel@redhat.com>
Acked-by: Mel Gorman <mgorman@suse.de>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Compaction of a zone is finished when the migrate scanner (which begins
at the zone's lowest pfn) meets the free page scanner (which begins at
the zone's highest pfn). This is detected in compact_zone() and in the
case of direct compaction, the compact_blockskip_flush flag is set so
that kswapd later resets the cached scanner pfn's, and a new compaction
may again start at the zone's borders.
The meeting of the scanners can happen during either scanner's activity.
However, it may currently fail to be detected when it occurs in the free
page scanner, due to two problems. First, isolate_freepages() keeps
free_pfn at the highest block where it isolated pages from, for the
purposes of not missing the pages that are returned back to allocator
when migration fails. Second, failing to isolate enough free pages due
to scanners meeting results in -ENOMEM being returned by
migrate_pages(), which makes compact_zone() bail out immediately without
calling compact_finished() that would detect scanners meeting.
This failure to detect scanners meeting might result in repeated
attempts at compaction of a zone that keep starting from the cached
pfn's close to the meeting point, and quickly failing through the
-ENOMEM path, without the cached pfns being reset, over and over. This
has been observed (through additional tracepoints) in the third phase of
the mmtests stress-highalloc benchmark, where the allocator runs on an
otherwise idle system. The problem was observed in the DMA32 zone,
which was used as a fallback to the preferred Normal zone, but on the
4GB system it was actually the largest zone. The problem is even
amplified for such fallback zone - the deferred compaction logic, which
could (after being fixed by a previous patch) reset the cached scanner
pfn's, is only applied to the preferred zone and not for the fallbacks.
The problem in the third phase of the benchmark was further amplified by
commit 81c0a2bb51 ("mm: page_alloc: fair zone allocator policy") which
resulted in a non-deterministic regression of the allocation success
rate from ~85% to ~65%. This occurs in about half of benchmark runs,
making bisection problematic. It is unlikely that the commit itself is
buggy, but it should put more pressure on the DMA32 zone during phases 1
and 2, which may leave it more fragmented in phase 3 and expose the bugs
that this patch fixes.
The fix is to make scanners meeting in isolate_freepage() stay that way,
and to check in compact_zone() for scanners meeting when migrate_pages()
returns -ENOMEM. The result is that compact_finished() also detects
scanners meeting and sets the compact_blockskip_flush flag to make
kswapd reset the scanner pfn's.
The results in stress-highalloc benchmark show that the "regression" by
commit 81c0a2bb51 in phase 3 no longer occurs, and phase 1 and 2
allocation success rates are also significantly improved.
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Compaction caches pfn's for its migrate and free scanners to avoid
scanning the whole zone each time. In compact_zone(), the cached values
are read to set up initial values for the scanners. There are several
situations when these cached pfn's are reset to the first and last pfn
of the zone, respectively. One of these situations is when a compaction
has been deferred for a zone and is now being restarted during a direct
compaction, which is also done in compact_zone().
However, compact_zone() currently reads the cached pfn's *before*
resetting them. This means the reset doesn't affect the compaction that
performs it, and with good chance also subsequent compactions, as
update_pageblock_skip() is likely to be called and update the cached
pfn's to those being processed. Another chance for a successful reset
is when a direct compaction detects that migration and free scanners
meet (which has its own problems addressed by another patch) and sets
update_pageblock_skip flag which kswapd uses to do the reset because it
goes to sleep.
This is clearly a bug that results in non-deterministic behavior, so
this patch moves the cached pfn reset to be performed *before* the
values are read.
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Mel Gorman <mgorman@suse.de>
Acked-by: Rik van Riel <riel@redhat.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently there are several functions to manipulate the deferred
compaction state variables. The remaining case where the variables are
touched directly is when a successful allocation occurs in direct
compaction, or is expected to be successful in the future by kswapd.
Here, the lowest order that is expected to fail is updated, and in the
case of successful allocation, the deferred status and counter is reset
completely.
Create a new function compaction_defer_reset() to encapsulate this
functionality and make it easier to understand the code. No functional
change.
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Mel Gorman <mgorman@suse.de>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The broad goal of the series is to improve allocation success rates for
huge pages through memory compaction, while trying not to increase the
compaction overhead. The original objective was to reintroduce
capturing of high-order pages freed by the compaction, before they are
split by concurrent activity. However, several bugs and opportunities
for simple improvements were found in the current implementation, mostly
through extra tracepoints (which are however too ugly for now to be
considered for sending).
The patches mostly deal with two mechanisms that reduce compaction
overhead, which is caching the progress of migrate and free scanners,
and marking pageblocks where isolation failed to be skipped during
further scans.
Patch 1 (from mgorman) adds tracepoints that allow calculate time spent in
compaction and potentially debug scanner pfn values.
Patch 2 encapsulates the some functionality for handling deferred compactions
for better maintainability, without a functional change
type is not determined without being actually needed.
Patch 3 fixes a bug where cached scanner pfn's are sometimes reset only after
they have been read to initialize a compaction run.
Patch 4 fixes a bug where scanners meeting is sometimes not properly detected
and can lead to multiple compaction attempts quitting early without
doing any work.
Patch 5 improves the chances of sync compaction to process pageblocks that
async compaction has skipped due to being !MIGRATE_MOVABLE.
Patch 6 improves the chances of sync direct compaction to actually do anything
when called after async compaction fails during allocation slowpath.
The impact of patches were validated using mmtests's stress-highalloc
benchmark with mmtests's stress-highalloc benchmark on a x86_64 machine
with 4GB memory.
Due to instability of the results (mostly related to the bugs fixed by
patches 2 and 3), 10 iterations were performed, taking min,mean,max
values for success rates and mean values for time and vmstat-based
metrics.
First, the default GFP_HIGHUSER_MOVABLE allocations were tested with the
patches stacked on top of v3.13-rc2. Patch 2 is OK to serve as baseline
due to no functional changes in 1 and 2. Comments below.
stress-highalloc
3.13-rc2 3.13-rc2 3.13-rc2 3.13-rc2 3.13-rc2
2-nothp 3-nothp 4-nothp 5-nothp 6-nothp
Success 1 Min 9.00 ( 0.00%) 10.00 (-11.11%) 43.00 (-377.78%) 43.00 (-377.78%) 33.00 (-266.67%)
Success 1 Mean 27.50 ( 0.00%) 25.30 ( 8.00%) 45.50 (-65.45%) 45.90 (-66.91%) 46.30 (-68.36%)
Success 1 Max 36.00 ( 0.00%) 36.00 ( 0.00%) 47.00 (-30.56%) 48.00 (-33.33%) 52.00 (-44.44%)
Success 2 Min 10.00 ( 0.00%) 8.00 ( 20.00%) 46.00 (-360.00%) 45.00 (-350.00%) 35.00 (-250.00%)
Success 2 Mean 26.40 ( 0.00%) 23.50 ( 10.98%) 47.30 (-79.17%) 47.60 (-80.30%) 48.10 (-82.20%)
Success 2 Max 34.00 ( 0.00%) 33.00 ( 2.94%) 48.00 (-41.18%) 50.00 (-47.06%) 54.00 (-58.82%)
Success 3 Min 65.00 ( 0.00%) 63.00 ( 3.08%) 85.00 (-30.77%) 84.00 (-29.23%) 85.00 (-30.77%)
Success 3 Mean 76.70 ( 0.00%) 70.50 ( 8.08%) 86.20 (-12.39%) 85.50 (-11.47%) 86.00 (-12.13%)
Success 3 Max 87.00 ( 0.00%) 86.00 ( 1.15%) 88.00 ( -1.15%) 87.00 ( 0.00%) 87.00 ( 0.00%)
3.13-rc2 3.13-rc2 3.13-rc2 3.13-rc2 3.13-rc2
2-nothp 3-nothp 4-nothp 5-nothp 6-nothp
User 6437.72 6459.76 5960.32 5974.55 6019.67
System 1049.65 1049.09 1029.32 1031.47 1032.31
Elapsed 1856.77 1874.48 1949.97 1994.22 1983.15
3.13-rc2 3.13-rc2 3.13-rc2 3.13-rc2 3.13-rc2
2-nothp 3-nothp 4-nothp 5-nothp 6-nothp
Minor Faults 253952267 254581900 250030122 250507333 250157829
Major Faults 420 407 506 530 530
Swap Ins 4 9 9 6 6
Swap Outs 398 375 345 346 333
Direct pages scanned 197538 189017 298574 287019 299063
Kswapd pages scanned 1809843 1801308 1846674 1873184 1861089
Kswapd pages reclaimed 1806972 1798684 1844219 1870509 1858622
Direct pages reclaimed 197227 188829 298380 286822 298835
Kswapd efficiency 99% 99% 99% 99% 99%
Kswapd velocity 953.382 970.449 952.243 934.569 922.286
Direct efficiency 99% 99% 99% 99% 99%
Direct velocity 104.058 101.832 153.961 143.200 148.205
Percentage direct scans 9% 9% 13% 13% 13%
Zone normal velocity 347.289 359.676 348.063 339.933 332.983
Zone dma32 velocity 710.151 712.605 758.140 737.835 737.507
Zone dma velocity 0.000 0.000 0.000 0.000 0.000
Page writes by reclaim 557.600 429.000 353.600 426.400 381.800
Page writes file 159 53 7 79 48
Page writes anon 398 375 345 346 333
Page reclaim immediate 825 644 411 575 420
Sector Reads 2781750 2769780 2878547 2939128 2910483
Sector Writes 12080843 12083351 12012892 12002132 12010745
Page rescued immediate 0 0 0 0 0
Slabs scanned 1575654 1545344 1778406 1786700 1794073
Direct inode steals 9657 10037 15795 14104 14645
Kswapd inode steals 46857 46335 50543 50716 51796
Kswapd skipped wait 0 0 0 0 0
THP fault alloc 97 91 81 71 77
THP collapse alloc 456 506 546 544 565
THP splits 6 5 5 4 4
THP fault fallback 0 1 0 0 0
THP collapse fail 14 14 12 13 12
Compaction stalls 1006 980 1537 1536 1548
Compaction success 303 284 562 559 578
Compaction failures 702 696 974 976 969
Page migrate success 1177325 1070077 3927538 3781870 3877057
Page migrate failure 0 0 0 0 0
Compaction pages isolated 2547248 2306457 8301218 8008500 8200674
Compaction migrate scanned 42290478 38832618 153961130 154143900 159141197
Compaction free scanned 89199429 79189151 356529027 351943166 356326727
Compaction cost 1566 1426 5312 5156 5294
NUMA PTE updates 0 0 0 0 0
NUMA hint faults 0 0 0 0 0
NUMA hint local faults 0 0 0 0 0
NUMA hint local percent 100 100 100 100 100
NUMA pages migrated 0 0 0 0 0
AutoNUMA cost 0 0 0 0 0
Observations:
- The "Success 3" line is allocation success rate with system idle
(phases 1 and 2 are with background interference). I used to get stable
values around 85% with vanilla 3.11. The lower min and mean values came
with 3.12. This was bisected to commit 81c0a2bb ("mm: page_alloc: fair
zone allocator policy") As explained in comment for patch 3, I don't
think the commit is wrong, but that it makes the effect of compaction
bugs worse. From patch 3 onwards, the results are OK and match the 3.11
results.
- Patch 4 also clearly helps phases 1 and 2, and exceeds any results
I've seen with 3.11 (I didn't measure it that thoroughly then, but it
was never above 40%).
- Compaction cost and number of scanned pages is higher, especially due
to patch 4. However, keep in mind that patches 3 and 4 fix existing
bugs in the current design of compaction overhead mitigation, they do
not change it. If overhead is found unacceptable, then it should be
decreased differently (and consistently, not due to random conditions)
than the current implementation does. In contrast, patches 5 and 6
(which are not strictly bug fixes) do not increase the overhead (but
also not success rates). This might be a limitation of the
stress-highalloc benchmark as it's quite uniform.
Another set of results is when configuring stress-highalloc t allocate
with similar flags as THP uses:
(GFP_HIGHUSER_MOVABLE|__GFP_NOMEMALLOC|__GFP_NORETRY|__GFP_NO_KSWAPD)
stress-highalloc
3.13-rc2 3.13-rc2 3.13-rc2 3.13-rc2 3.13-rc2
2-thp 3-thp 4-thp 5-thp 6-thp
Success 1 Min 2.00 ( 0.00%) 7.00 (-250.00%) 18.00 (-800.00%) 19.00 (-850.00%) 26.00 (-1200.00%)
Success 1 Mean 19.20 ( 0.00%) 17.80 ( 7.29%) 29.20 (-52.08%) 29.90 (-55.73%) 32.80 (-70.83%)
Success 1 Max 27.00 ( 0.00%) 29.00 ( -7.41%) 35.00 (-29.63%) 36.00 (-33.33%) 37.00 (-37.04%)
Success 2 Min 3.00 ( 0.00%) 8.00 (-166.67%) 21.00 (-600.00%) 21.00 (-600.00%) 32.00 (-966.67%)
Success 2 Mean 19.30 ( 0.00%) 17.90 ( 7.25%) 32.20 (-66.84%) 32.60 (-68.91%) 35.70 (-84.97%)
Success 2 Max 27.00 ( 0.00%) 30.00 (-11.11%) 36.00 (-33.33%) 37.00 (-37.04%) 39.00 (-44.44%)
Success 3 Min 62.00 ( 0.00%) 62.00 ( 0.00%) 85.00 (-37.10%) 75.00 (-20.97%) 64.00 ( -3.23%)
Success 3 Mean 66.30 ( 0.00%) 65.50 ( 1.21%) 85.60 (-29.11%) 83.40 (-25.79%) 83.50 (-25.94%)
Success 3 Max 70.00 ( 0.00%) 69.00 ( 1.43%) 87.00 (-24.29%) 86.00 (-22.86%) 87.00 (-24.29%)
3.13-rc2 3.13-rc2 3.13-rc2 3.13-rc2 3.13-rc2
2-thp 3-thp 4-thp 5-thp 6-thp
User 6547.93 6475.85 6265.54 6289.46 6189.96
System 1053.42 1047.28 1043.23 1042.73 1038.73
Elapsed 1835.43 1821.96 1908.67 1912.74 1956.38
3.13-rc2 3.13-rc2 3.13-rc2 3.13-rc2 3.13-rc2
2-thp 3-thp 4-thp 5-thp 6-thp
Minor Faults 256805673 253106328 253222299 249830289 251184418
Major Faults 395 375 423 434 448
Swap Ins 12 10 10 12 9
Swap Outs 530 537 487 455 415
Direct pages scanned 71859 86046 153244 152764 190713
Kswapd pages scanned 1900994 1870240 1898012 1892864 1880520
Kswapd pages reclaimed 1897814 1867428 1894939 1890125 1877924
Direct pages reclaimed 71766 85908 153167 152643 190600
Kswapd efficiency 99% 99% 99% 99% 99%
Kswapd velocity 1029.000 1067.782 1000.091 991.049 951.218
Direct efficiency 99% 99% 99% 99% 99%
Direct velocity 38.897 49.127 80.747 79.983 96.468
Percentage direct scans 3% 4% 7% 7% 9%
Zone normal velocity 351.377 372.494 348.910 341.689 335.310
Zone dma32 velocity 716.520 744.414 731.928 729.343 712.377
Zone dma velocity 0.000 0.000 0.000 0.000 0.000
Page writes by reclaim 669.300 604.000 545.700 538.900 429.900
Page writes file 138 66 58 83 14
Page writes anon 530 537 487 455 415
Page reclaim immediate 806 655 772 548 517
Sector Reads 2711956 2703239 2811602 2818248 2839459
Sector Writes 12163238 12018662 12038248 11954736 11994892
Page rescued immediate 0 0 0 0 0
Slabs scanned 1385088 1388364 1507968 1513292 1558656
Direct inode steals 1739 2564 4622 5496 6007
Kswapd inode steals 47461 46406 47804 48013 48466
Kswapd skipped wait 0 0 0 0 0
THP fault alloc 110 82 84 69 70
THP collapse alloc 445 482 467 462 539
THP splits 6 5 4 5 3
THP fault fallback 3 0 0 0 0
THP collapse fail 15 14 14 14 13
Compaction stalls 659 685 1033 1073 1111
Compaction success 222 225 410 427 456
Compaction failures 436 460 622 646 655
Page migrate success 446594 439978 1085640 1095062 1131716
Page migrate failure 0 0 0 0 0
Compaction pages isolated 1029475 1013490 2453074 2482698 2565400
Compaction migrate scanned 9955461 11344259 24375202 27978356 30494204
Compaction free scanned 27715272 28544654 80150615 82898631 85756132
Compaction cost 552 555 1344 1379 1436
NUMA PTE updates 0 0 0 0 0
NUMA hint faults 0 0 0 0 0
NUMA hint local faults 0 0 0 0 0
NUMA hint local percent 100 100 100 100 100
NUMA pages migrated 0 0 0 0 0
AutoNUMA cost 0 0 0 0 0
There are some differences from the previous results for THP-like allocations:
- Here, the bad result for unpatched kernel in phase 3 is much more
consistent to be between 65-70% and not related to the "regression" in
3.12. Still there is the improvement from patch 4 onwards, which brings
it on par with simple GFP_HIGHUSER_MOVABLE allocations.
- Compaction costs have increased, but nowhere near as much as the
non-THP case. Again, the patches should be worth the gained
determininsm.
- Patches 5 and 6 somewhat increase the number of migrate-scanned pages.
This is most likely due to __GFP_NO_KSWAPD flag, which means the cached
pfn's and pageblock skip bits are not reset by kswapd that often (at
least in phase 3 where no concurrent activity would wake up kswapd) and
the patches thus help the sync-after-async compaction. It doesn't
however show that the sync compaction would help so much with success
rates, which can be again seen as a limitation of the benchmark
scenario.
This patch (of 6):
Add two tracepoints for compaction begin and end of a zone. Using this it
is possible to calculate how much time a workload is spending within
compaction and potentially debug problems related to cached pfns for
scanning. In combination with the direct reclaim and slab trace points it
should be possible to estimate most allocation-related overhead for a
workload.
Signed-off-by: Mel Gorman <mgorman@suse.de>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Rik van Riel <riel@redhat.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
mem_cgroup_print_oom_info uses a static buffer (memcg_name) to store the
name of the cgroup. This is not safe as pointed out by David Rientjes
because memcg oom is locked only for its hierarchy and nothing prevents
another parallel hierarchy to trigger oom as well and overwrite the
already in-use buffer.
This patch introduces oom_info_lock hidden inside
mem_cgroup_print_oom_info which is held throughout the function. It
makes access to memcg_name safe and as a bonus it also prevents parallel
memcg ooms to interleave their statistics which would make the printed
data hard to analyze otherwise.
Signed-off-by: Michal Hocko <mhocko@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
