Signed-off-by: NStefan Schmidt <s.schmidt@samsung.com>
Acked-by: NAlexander Aring <alex.aring@gmail.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

Signed-off-by: NStefan Schmidt <s.schmidt@samsung.com>
Acked-by: NAlexander Aring <alex.aring@gmail.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

Signed-off-by: NStefan Schmidt <s.schmidt@samsung.com>
Acked-by: NAlexander Aring <alex.aring@gmail.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

This patch adds the default cca setting after device reset for at86rf230
driver.
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

The current cca setting handle is a driver specific call. We need to
introduce some 802.15.4 specific layer and mapping 802.15.4 cca modes to
driver specific ones inside the 802.15.4 driver. This patch will add
such 802.15.4 layer and mapping the cca settings to driver specific ones.
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

Set hdev->set_bdaddr handler for ath3012. It sends the vendor specific HCI
command to change the public address. The change doesn't persist across
power cycle.
Signed-off-by: NToshi Kikuchi <toshik@chromium.org>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

An earlier commit to resolve an issue with encapsulation offloads missed
setting a bit in the outer netdev features flag. This results in loss of TSO
feature on a VxLAN interface.

Fixes: 630f4b70 ("Export tunnel offloads only when a VxLAN tunnel is created")
Signed-off-by: NSriharsha Basavapatna <sriharsha.basavapatna@emulex.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Noticed when debugging ptp.
Signed-off-by: NJiri Benc <jbenc@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Commit bc96f648 (xen-netback: make
feature-rx-notify mandatory) incorrectly assumed that there were no
frontends in use that did not support this feature.  But the frontend
driver in MiniOS does not and since this is used by (qemu) stubdoms,
these stopped working.

Netback sort of works as-is in this mode except:

- If there are no Rx requests and the internal Rx queue fills, only
  the drain timeout will wake the thread.  The default drain timeout
  of 10 s would give unacceptable pauses.

- If an Rx stall was detected and the internal Rx queue is drained,
  then the Rx thread would never wake.

Handle these two cases (when feature-rx-notify is disabled) by:

- Reducing the drain timeout to 30 ms.

- Disabling Rx stall detection.
Reported-by: NJohn <jw@nuclearfallout.net>
Tested-by: NJohn <jw@nuclearfallout.net>
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>
Reviewed-by: NWei Liu <wei.liu2@citrix.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

QSA module was getting decoded as QSFP module in ethtool get settings, this
patch fixes it.
Signed-off-by: NHariprasad Shenai <hariprasad@chelsio.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The current implementations all use dev_uc_add_excl() and such whose API
doesn't support vlans, so we can't make it with NICs HW for now.

Fixes: f6f6424b ('net: make vid as a parameter for ndo_fdb_add/ndo_fdb_del')
Signed-off-by: NOr Gerlitz <ogerlitz@mellanox.com>
Reviewed-by: NJiri Pirko <jiri@resnulli.us>
Acked-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This commit contains 2 fixes for the 128B CQE/EQE stride feaure.
Wei found that mlx4_QUERY_HCA function marked the wrong capability
in flags (64B CQE/EQE), when CQE/EQE stride feature was enabled.
Also added small fix in initial CQE ownership bit assignment, when CQE
is size is not default 32B.

Fixes: 77507aa2 (net/mlx4: Enable CQE/EQE stride support)
Signed-off-by: NWei Yang <weiyang@linux.vnet.ibm.com>
Signed-off-by: NIdo Shamay <idos@mellanox.com>
Signed-off-by: NAmir Vadai <amirv@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Do camera capture test on i.MX6q sabresd board, and save the capture data to
nfs rootfs. The command is:
gst-launch-1.0 -e imxv4l2src device=/dev/video1 num-buffers=2592000 ! tee name=t !
queue ! imxv4l2sink sync=false t. ! queue ! vpuenc ! queue ! mux. pulsesrc num-buffers=3720937
blocksize=4096 ! 'audio/x-raw, rate=44100, channels=2' ! queue ! imxmp3enc ! mpegaudioparse !
queue ! mux. qtmux name=mux ! filesink location=video_recording_long.mov

After about 10 hours running, there have net watchdog timeout kernel dump:
...
WARNING: CPU: 0 PID: 0 at net/sched/sch_generic.c:264 dev_watchdog+0x2b4/0x2d8()
NETDEV WATCHDOG: eth0 (fec): transmit queue 0 timed out
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 3.14.24-01051-gdb840b7 #440
[<80014e6c>] (unwind_backtrace) from [<800118ac>] (show_stack+0x10/0x14)
[<800118ac>] (show_stack) from [<806ae3f0>] (dump_stack+0x78/0xc0)
[<806ae3f0>] (dump_stack) from [<8002b504>] (warn_slowpath_common+0x68/0x8c)
[<8002b504>] (warn_slowpath_common) from [<8002b558>] (warn_slowpath_fmt+0x30/0x40)
[<8002b558>] (warn_slowpath_fmt) from [<8055e0d4>] (dev_watchdog+0x2b4/0x2d8)
[<8055e0d4>] (dev_watchdog) from [<800352d8>] (call_timer_fn.isra.33+0x24/0x8c)
[<800352d8>] (call_timer_fn.isra.33) from [<800354c4>] (run_timer_softirq+0x184/0x220)
[<800354c4>] (run_timer_softirq) from [<8002f420>] (__do_softirq+0xc0/0x22c)
[<8002f420>] (__do_softirq) from [<8002f804>] (irq_exit+0xa8/0xf4)
[<8002f804>] (irq_exit) from [<8000ee5c>] (handle_IRQ+0x54/0xb4)
[<8000ee5c>] (handle_IRQ) from [<80008598>] (gic_handle_irq+0x28/0x5c)
[<80008598>] (gic_handle_irq) from [<800123c0>] (__irq_svc+0x40/0x74)
Exception stack(0x80d27f18 to 0x80d27f60)
7f00:                                                       80d27f60 0000014c
7f20: 8858c60e 0000004d 884e4540 0000004d ab7250d0 80d34348 00000000 00000000
7f40: 00000001 00000000 00000017 80d27f60 800702a4 80476e6c 600f0013 ffffffff
[<800123c0>] (__irq_svc) from [<80476e6c>] (cpuidle_enter_state+0x50/0xe0)
[<80476e6c>] (cpuidle_enter_state) from [<80476fa8>] (cpuidle_idle_call+0xac/0x154)
[<80476fa8>] (cpuidle_idle_call) from [<8000f174>] (arch_cpu_idle+0x8/0x44)
[<8000f174>] (arch_cpu_idle) from [<80064c54>] (cpu_startup_entry+0x100/0x158)
[<80064c54>] (cpu_startup_entry) from [<80cd8a9c>] (start_kernel+0x304/0x368)
---[ end trace 09ebd32fb032f86d ]---
...

There might have a race in napi_schedule(), leaving interrupts disabled forever.
After these patch, the case still work more than 40 hours running.
Signed-off-by: NFugang Duan <B38611@freescale.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

After d75b1ade (net: less interrupt
masking in NAPI) the napi instance is removed from the per-cpu list
prior to calling the n->poll(), and is only requeued if all of the
budget was used.  This inadvertently broke netfront because netfront
does not use NAPI correctly.

If netfront had not used all of its budget it would do a final check
for any Rx responses and avoid calling napi_complete() if there were
more responses.  It would still return under budget so it would never
be rescheduled.  The final check would also not re-enable the Rx
interrupt.

Additionally, xenvif_poll() would also call napi_complete() /after/
enabling the interrupt.  This resulted in a race between the
napi_complete() and the napi_schedule() in the interrupt handler.  The
use of local_irq_save/restore() avoided by race iff the handler is
running on the same CPU but not if it was running on a different CPU.

Fix both of these by always calling napi_compete() if the budget was
not all used, and then calling napi_schedule() if the final checks
says there's more work.
Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>
Cc: Eric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Otherwise we get things like:

warning: (NET_DSA_BCM_SF2 && BCMGENET && SYSTEMPORT) selects FIXED_PHY which has unmet direct dependencies (NETDEVICES && PHYLIB=y)

In order to make this work we have to rename fixed.c to fixed_phy.c
because the regulator drivers already have a module named "fixed.o".
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Use TUNSETVNETLE/TUNGETVNETLE instead.
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Use TUNSETVNETLE/TUNGETVNETLE instead.
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

flags field in ifreq is only 16 bit wide, but
we read it as a 32 bit value.
If userspace doesn't zero-initialize unused fields,
this will lead to failures.
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

There is no need to do the following:

select FIXED_PHY if NET_DSA_BCM_SF2=y, as this implies that we will not be
able to build and/or run the driver correctly when built as a module,
which is no longer an issue since commit 37e9a690 ("net: phy: export
fixed_phy_register()").

Fixes: 246d7f77 ("net: dsa: add Broadcom SF2 switch driver")
Signed-off-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

There is no need to do the following:

select FIXED_PHY if SYSTEMPORT=y, as this implies that we will not be able
to build and/or run the driver correctly when built as a module, which
is no longer an issue since commit 37e9a690 ("net: phy: export
fixed_phy_register()")

Fixes: a3862db2 ("net: systemport: hook SYSTEMPORT driver in the build")
Signed-off-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

There is no need to do the following:

select FIXED_PHY if BCMGENET=y, as this implies that we will not be able
to build and/or run the driver correctly when built as a module, which
is no longer an issue since commit 37e9a690 ("net: phy: export
fixed_phy_register()")

Fixes: b0ba512e225d ("net: bcmgenet: enable driver to work without device tree"
Fixes: bdaa53bd ("net: bcmgenet: hook into the build system")
Signed-off-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The setting of this flag was missed in previous modifications.
Signed-off-by: NLarry Finger <Larry.Finger@lwfinger.net>
Cc: Stable <stable@vger.kernel.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Debug code prints the fifo name via custom dev_warn() wrappers. The
fifo_names array is only non-zero when debugging is manually enabled,
which is all well and good. However, it's *not* good that this array
uses zero-length arrays in the non-debug case, and so it doesn't
actually have any memory allocated to it. This means that as far as we
know, fifo_names[i] actually points to garbage memory.

I've seen this in my log:

[ 4601.205511] brcmsmac bcma0:1: wl0: brcms_c_d11hdrs_mac80211: �GeL txop exceeded phylen 137/256 dur 1602/1504

So let's give this array space enough to fill it with a NULL byte.
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>
Cc: Brett Rudley <brudley@broadcom.com>
Cc: Arend van Spriel <arend@broadcom.com>
Cc: "Franky (Zhenhui) Lin" <frankyl@broadcom.com>
Cc: Hante Meuleman <meuleman@broadcom.com>
Cc: "John W. Linville" <linville@tuxdriver.com>
Cc: linux-wireless@vger.kernel.org
Cc: brcm80211-dev-list@broadcom.com
Cc: netdev@vger.kernel.org
Acked-by: NArend van Spriel <arend@broadcom.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Fixes the following sparse warning:

drivers/net/wireless/rtlwifi/rtl8192cu/hw.c:1595:6: warning:
 symbol 'usb_cmd_send_packet' was not declared. Should it be static?
Signed-off-by: NWei Yongjun <yongjun_wei@trendmicro.com.cn>
Acked-by: NLarry Finger <Larry.Finger@lwfinger.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Replace a misspelled function name by %s and then __func__.

8821 was written as 8812.

This was done using Coccinelle, including the use of Levenshtein distance,
as proposed by Rasmus Villemoes.
Signed-off-by: NJulia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Replace a misspelled function name by %s and then __func__.

This was done using Coccinelle, including the use of Levenshtein distance,
as proposed by Rasmus Villemoes.
Signed-off-by: NJulia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Replace a misspelled function name by %s and then __func__.

This was done using Coccinelle, including the use of Levenshtein distance,
as proposed by Rasmus Villemoes.
Signed-off-by: NJulia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Inside macb_probe(), when devm_request_irq() fails on queue q, there is no need
to call devm_free_irq() on queues 0..q-1 because the managed device resources
are released later when calling free_netdev().

Also removing devm_free_irq() call from macb_remove() for the same reason.
Signed-off-by: NCyrille Pitchen <cyrille.pitchen@atmel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

fix a bug introduced by the multiqueue support patch:
"net/macb: add TX multiqueue support for gem"

the "bp" pointer to the netdev private data was dereferenced and used after the
associated memory had been freed by calling free_netdev().
Signed-off-by: NCyrille Pitchen <cyrille.pitchen@atmel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

If CONFIG_OF is not set:

drivers/net/ethernet/stmicro/stmmac/dwmac-sti.c: In function ‘sti_dwmac_parse_data’:
drivers/net/ethernet/stmicro/stmmac/dwmac-sti.c:318: warning: ‘rs’ is used uninitialized in this function

of_property_read_string() will return -ENOSYS in this case, and rs will
be an uninitialized pointer.

While the fallback clock selection is already selected correctly in this
case, the string comparisons should be skipped too, else the system will
crash while dereferencing the uninitialized pointer.
Signed-off-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

If GPIOLIB=n the following build errors occur:

drivers/net/ethernet/smsc/smc91x.c: In function 'try_toggle_control_gpio':
drivers/net/ethernet/smsc/smc91x.c:2204:2: error: implicit declaration of function 'devm_gpiod_get_index' [-Werror=implicit-function-declaration]
drivers/net/ethernet/smsc/smc91x.c:2204:7: warning: assignment makes pointer from integer without a cast [enabled by default]
drivers/net/ethernet/smsc/smc91x.c:2213:2: error: implicit declaration of function 'gpiod_direction_output' [-Werror=implicit-function-declaration]
drivers/net/ethernet/smsc/smc91x.c:2216:3: error: implicit declaration of function 'devm_gpiod_put' [-Werror=implicit-function-declaration]
drivers/net/ethernet/smsc/smc91x.c:2222:2: error: implicit declaration of function 'gpiod_set_value_cansleep' [-Werror=implicit-function-declaration]

Fix this by letting the driver depend on GPIOLIB if OF is selected.

Fixes: 7d2911c4 ("net: smc91x: Fix gpios for device tree based booting")
Cc: Tony Lindgren <tony@atomide.com>
Signed-off-by: NTobias Klauser <tklauser@distanz.ch>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

To be future-proof and for better readability the time comparisons are
modified to use time_before, time_after, and time_after_eq instead of
plain, error-prone math.
Signed-off-by: NAsaf Vertz <asaf.vertz@tandemg.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

To support asymmetric EQ allocations, we should query the device
capabilities prior to enabling SRIOV. As a side effect of adding that,
we are dumping the PF device capabilities twice. Avoid that by moving
the printing into a helper function which is called once.

Fixes: 7ae0e400 ('net/mlx4_core: Flexible (asymmetric) allocation of
		     EQs and MSI-X vectors for PF/VFs')
Signed-off-by: NOr Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The current mlx4_load_one has a memory leak as it always allocates
dev_cap, but frees it only on error.

In addition, even if VFs exist when mlx4_load_one is called,
we still need to notify probed VFs that we're loading (by
incrementing pf_loading).

Fixes: a0eacca9 ('net/mlx4_core: Refactor mlx4_load_one')
Signed-off-by: NMatan Barak <matanb@mellanox.com>
Signed-off-by: NOr Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In current zram, we use DEVICE_ATTR() to define sys device attributes.
SO, we need to set (S_IRUGO | S_IWUSR) permission and other arguments
manually.  Linux already provids the macro DEVICE_ATTR_[RW|RO|WO] to
define sys device attribute.  It is simple and readable.

This patch uses kernel defined macro DEVICE_ATTR_[RW|RO|WO] to define
zram device attribute.
Signed-off-by: NGanesh Mahendran <opensource.ganesh@gmail.com>
Acked-by: NJerome Marchand <jmarchan@redhat.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

In struct zram_table_entry, the element *value* contains obj size and obj
zram flags.  Bit 0 to bit (ZRAM_FLAG_SHIFT - 1) represent obj size, and
bit ZRAM_FLAG_SHIFT to the highest bit of unsigned long represent obj
zram_flags.  So the first zram flag(ZRAM_ZERO) should be from
ZRAM_FLAG_SHIFT instead of (ZRAM_FLAG_SHIFT + 1).

This patch fixes this cosmetic issue.

Also fix a typo, "page in now accessed" -> "page is now accessed"
Signed-off-by: NMahendran Ganesh <opensource.ganesh@gmail.com>
Acked-by: NMinchan Kim <minchan@kernel.org>
Acked-by: NWeijie Yang <weijie.yang@samsung.com>
Acked-by: NSergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Nitin Gupta <ngupta@vflare.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This patch implements rw_page operation for zram block device.

I implemented the feature in zram and tested it.  Test bed was the G2, LG
electronic mobile device, whtich has msm8974 processor and 2GB memory.

With a memory allocation test program consuming memory, the system
generates swap.

Operating time of swap_write_page() was measured.

--------------------------------------------------
|             |   operating time   | improvement |
|             |  (20 runs average) |             |
--------------------------------------------------
|with patch   |    1061.15 us      |    +2.4%    |
--------------------------------------------------
|without patch|    1087.35 us      |             |
--------------------------------------------------

Each test(with paged_io,with BIO) result set shows normal distribution and
has equal variance.  I mean the two values are valid result to compare.  I
can say operation with paged I/O(without BIO) is faster 2.4% with
confidence level 95%.

[minchan@kernel.org: make rw_page opeartion return 0]
[minchan@kernel.org: rely on the bi_end_io for zram_rw_page fails]
[sergey.senozhatsky@gmail.com: code cleanup]
[minchan@kernel.org: add comment]
Signed-off-by: Nkaram.lee <karam.lee@lge.com>
Acked-by: NMinchan Kim <minchan@kernel.org>
Acked-by: NJerome Marchand <jmarchan@redhat.com>
Cc: Matthew Wilcox <matthew.r.wilcox@intel.com>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: <seungho1.park@lge.com>
Signed-off-by: NMinchan Kim <minchan@kernel.org>
Signed-off-by: NSergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This patch changes parameter of valid_io_request for common usage.  The
purpose of valid_io_request() is to determine if bio request is valid or
not.

This patch use I/O start address and size instead of a BIO parameter for
common usage.
Signed-off-by: Nkaram.lee <karam.lee@lge.com>
Acked-by: NMinchan Kim <minchan@kernel.org>
Acked-by: NJerome Marchand <jmarchan@redhat.com>
Cc: Matthew Wilcox <matthew.r.wilcox@intel.com>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: <seungho1.park@lge.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Recently rw_page block device operation has been added.  This patchset
implements rw_page operation for zram block device and does some clean-up.

This patch (of 3):

Remove an unnecessary parameter(bio) from zram_bvec_rw() and
zram_bvec_read().  zram_bvec_read() doesn't use a bio parameter, so remove
it.  zram_bvec_rw() calls a read/write operation not using bio, so a rw
parameter replaces a bio parameter.
Signed-off-by: Nkaram.lee <karam.lee@lge.com>
Acked-by: NMinchan Kim <minchan@kernel.org>
Acked-by: NJerome Marchand <jmarchan@redhat.com>
Cc: Matthew Wilcox <matthew.r.wilcox@intel.com>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: <seungho1.park@lge.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The slab shrinkers are currently invoked from the zonelist walkers in
kswapd, direct reclaim, and zone reclaim, all of which roughly gauge the
eligible LRU pages and assemble a nodemask to pass to NUMA-aware
shrinkers, which then again have to walk over the nodemask.  This is
redundant code, extra runtime work, and fairly inaccurate when it comes to
the estimation of actually scannable LRU pages.  The code duplication will
only get worse when making the shrinkers cgroup-aware and requiring them
to have out-of-band cgroup hierarchy walks as well.

Instead, invoke the shrinkers from shrink_zone(), which is where all
reclaimers end up, to avoid this duplication.

Take the count for eligible LRU pages out of get_scan_count(), which
considers many more factors than just the availability of swap space, like
zone_reclaimable_pages() currently does.  Accumulate the number over all
visited lruvecs to get the per-zone value.

Some nodes have multiple zones due to memory addressing restrictions.  To
avoid putting too much pressure on the shrinkers, only invoke them once
for each such node, using the class zone of the allocation as the pivot
zone.

For now, this integrates the slab shrinking better into the reclaim logic
and gets rid of duplicative invocations from kswapd, direct reclaim, and
zone reclaim.  It also prepares for cgroup-awareness, allowing
memcg-capable shrinkers to be added at the lruvec level without much
duplication of both code and runtime work.

This changes kswapd behavior, which used to invoke the shrinkers for each
zone, but with scan ratios gathered from the entire node, resulting in
meaningless pressure quantities on multi-zone nodes.

Zone reclaim behavior also changes.  It used to shrink slabs until the
same amount of pages were shrunk as were reclaimed from the LRUs.  Now it
merely invokes the shrinkers once with the zone's scan ratio, which makes
the shrinkers go easier on caches that implement aging and would prefer
feeding back pressure from recently used slab objects to unused LRU pages.

[vdavydov@parallels.com: assure class zone is populated]
Signed-off-by: NJohannes Weiner <hannes@cmpxchg.org>
Cc: Dave Chinner <david@fromorbit.com>
Signed-off-by: NVladimir Davydov <vdavydov@parallels.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>