<feed xmlns='http://www.w3.org/2005/Atom'>
<title>pm24.git/drivers/net/ethernet/intel, branch perf-mon</title>
<subtitle>Unnamed repository; edit this file 'description' to name the repository.
</subtitle>
<id>https://git.kobert.dev/pm24.git/atom?h=perf-mon</id>
<link rel='self' href='https://git.kobert.dev/pm24.git/atom?h=perf-mon'/>
<link rel='alternate' type='text/html' href='https://git.kobert.dev/pm24.git/'/>
<updated>2025-02-03T21:18:44Z</updated>
<entry>
<title>Merge branch '100GbE' of git://git.kernel.org/pub/scm/linux/kernel/git/tnguy/net-queue</title>
<updated>2025-02-03T21:18:44Z</updated>
<author>
<name>Jakub Kicinski</name>
<email>kuba@kernel.org</email>
</author>
<published>2025-02-03T21:18:44Z</published>
<link rel='alternate' type='text/html' href='https://git.kobert.dev/pm24.git/commit/?id=88be092224d51f6ca7b369a8e5d29cfee8754a32'/>
<id>urn:sha1:88be092224d51f6ca7b369a8e5d29cfee8754a32</id>
<content type='text'>
Tony Nguyen says:

====================
ice: fix Rx data path for heavy 9k MTU traffic

Maciej Fijalkowski says:

This patchset fixes a pretty nasty issue that was reported by RedHat
folks which occurred after ~30 minutes (this value varied, just trying
here to state that it was not observed immediately but rather after a
considerable longer amount of time) when ice driver was tortured with
jumbo frames via mix of iperf traffic executed simultaneously with
wrk/nginx on client/server sides (HTTP and TCP workloads basically).

The reported splats were spanning across all the bad things that can
happen to the state of page - refcount underflow, use-after-free, etc.
One of these looked as follows:

[ 2084.019891] BUG: Bad page state in process swapper/34  pfn:97fcd0
[ 2084.025990] page:00000000a60ee772 refcount:-1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x97fcd0
[ 2084.035462] flags: 0x17ffffc0000000(node=0|zone=2|lastcpupid=0x1fffff)
[ 2084.041990] raw: 0017ffffc0000000 dead000000000100 dead000000000122 0000000000000000
[ 2084.049730] raw: 0000000000000000 0000000000000000 ffffffffffffffff 0000000000000000
[ 2084.057468] page dumped because: nonzero _refcount
[ 2084.062260] Modules linked in: bonding tls sunrpc intel_rapl_msr intel_rapl_common intel_uncore_frequency intel_uncore_frequency_common i10nm_edac nfit libnvdimm x86_pkg_temp_thermal intel_powerclamp coretemp kvm_intel kvm mgag200 irqd
[ 2084.137829] CPU: 34 PID: 0 Comm: swapper/34 Kdump: loaded Not tainted 5.14.0-427.37.1.el9_4.x86_64 #1
[ 2084.147039] Hardware name: Dell Inc. PowerEdge R750/0216NK, BIOS 1.13.2 12/19/2023
[ 2084.154604] Call Trace:
[ 2084.157058]  &lt;IRQ&gt;
[ 2084.159080]  dump_stack_lvl+0x34/0x48
[ 2084.162752]  bad_page.cold+0x63/0x94
[ 2084.166333]  check_new_pages+0xb3/0xe0
[ 2084.170083]  rmqueue_bulk+0x2d2/0x9e0
[ 2084.173749]  ? ktime_get+0x35/0xa0
[ 2084.177159]  rmqueue_pcplist+0x13b/0x210
[ 2084.181081]  rmqueue+0x7d3/0xd40
[ 2084.184316]  ? xas_load+0x9/0xa0
[ 2084.187547]  ? xas_find+0x183/0x1d0
[ 2084.191041]  ? xa_find_after+0xd0/0x130
[ 2084.194879]  ? intel_iommu_iotlb_sync_map+0x89/0xe0
[ 2084.199759]  get_page_from_freelist+0x11f/0x530
[ 2084.204291]  __alloc_pages+0xf2/0x250
[ 2084.207958]  ice_alloc_rx_bufs+0xcc/0x1c0 [ice]
[ 2084.212543]  ice_clean_rx_irq+0x631/0xa20 [ice]
[ 2084.217111]  ice_napi_poll+0xdf/0x2a0 [ice]
[ 2084.221330]  __napi_poll+0x27/0x170
[ 2084.224824]  net_rx_action+0x233/0x2f0
[ 2084.228575]  __do_softirq+0xc7/0x2ac
[ 2084.232155]  __irq_exit_rcu+0xa1/0xc0
[ 2084.235821]  common_interrupt+0x80/0xa0
[ 2084.239662]  &lt;/IRQ&gt;
[ 2084.241768]  &lt;TASK&gt;

The fix is mostly about reverting what was done in commit 1dc1a7e7f410
("ice: Centrallize Rx buffer recycling") followed by proper timing on
page_count() storage and then removing the ice_rx_buf::act related logic
(which was mostly introduced for purposes from cited commit).

Special thanks to Xu Du for providing reproducer and Jacob Keller for
initial extensive analysis.

* '100GbE' of git://git.kernel.org/pub/scm/linux/kernel/git/tnguy/net-queue:
  ice: stop storing XDP verdict within ice_rx_buf
  ice: gather page_count()'s of each frag right before XDP prog call
  ice: put Rx buffers after being done with current frame
====================

Link: https://patch.msgid.link/20250131185415.3741532-1-anthony.l.nguyen@intel.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</content>
</entry>
<entry>
<title>ice: Add check for devm_kzalloc()</title>
<updated>2025-02-02T00:57:50Z</updated>
<author>
<name>Jiasheng Jiang</name>
<email>jiashengjiangcool@gmail.com</email>
</author>
<published>2025-01-31T01:38:32Z</published>
<link rel='alternate' type='text/html' href='https://git.kobert.dev/pm24.git/commit/?id=a8aa6a6ddce9b5585f2b74f27f3feea1427fb4e7'/>
<id>urn:sha1:a8aa6a6ddce9b5585f2b74f27f3feea1427fb4e7</id>
<content type='text'>
Add check for the return value of devm_kzalloc() to guarantee the success
of allocation.

Fixes: 42c2eb6b1f43 ("ice: Implement devlink-rate API")
Signed-off-by: Jiasheng Jiang &lt;jiashengjiangcool@gmail.com&gt;
Reviewed-by: Michal Swiatkowski &lt;michal.swiatkowski@linux.intel.com&gt;
Link: https://patch.msgid.link/20250131013832.24805-1-jiashengjiangcool@gmail.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</content>
</entry>
<entry>
<title>ice: stop storing XDP verdict within ice_rx_buf</title>
<updated>2025-01-31T18:07:46Z</updated>
<author>
<name>Maciej Fijalkowski</name>
<email>maciej.fijalkowski@intel.com</email>
</author>
<published>2025-01-23T15:01:18Z</published>
<link rel='alternate' type='text/html' href='https://git.kobert.dev/pm24.git/commit/?id=468a1952df78f65c5991b7ac885c8b5b7dd87bab'/>
<id>urn:sha1:468a1952df78f65c5991b7ac885c8b5b7dd87bab</id>
<content type='text'>
Idea behind having ice_rx_buf::act was to simplify and speed up the Rx
data path by walking through buffers that were representing cleaned HW
Rx descriptors. Since it caused us a major headache recently and we
rolled back to old approach that 'puts' Rx buffers right after running
XDP prog/creating skb, this is useless now and should be removed.

Get rid of ice_rx_buf::act and related logic. We still need to take care
of a corner case where XDP program releases a particular fragment.

Make ice_run_xdp() to return its result and use it within
ice_put_rx_mbuf().

Fixes: 2fba7dc5157b ("ice: Add support for XDP multi-buffer on Rx side")
Reviewed-by: Przemek Kitszel &lt;przemyslaw.kitszel@intel.com&gt;
Reviewed-by: Simon Horman &lt;horms@kernel.org&gt;
Signed-off-by: Maciej Fijalkowski &lt;maciej.fijalkowski@intel.com&gt;
Tested-by: Chandan Kumar Rout &lt;chandanx.rout@intel.com&gt; (A Contingent Worker at Intel)
Signed-off-by: Tony Nguyen &lt;anthony.l.nguyen@intel.com&gt;
</content>
</entry>
<entry>
<title>ice: gather page_count()'s of each frag right before XDP prog call</title>
<updated>2025-01-31T18:06:26Z</updated>
<author>
<name>Maciej Fijalkowski</name>
<email>maciej.fijalkowski@intel.com</email>
</author>
<published>2025-01-23T15:01:17Z</published>
<link rel='alternate' type='text/html' href='https://git.kobert.dev/pm24.git/commit/?id=11c4aa074d547d825b19cd8d9f288254d89d805c'/>
<id>urn:sha1:11c4aa074d547d825b19cd8d9f288254d89d805c</id>
<content type='text'>
If we store the pgcnt on few fragments while being in the middle of
gathering the whole frame and we stumbled upon DD bit not being set, we
terminate the NAPI Rx processing loop and come back later on. Then on
next NAPI execution we work on previously stored pgcnt.

Imagine that second half of page was used actively by networking stack
and by the time we came back, stack is not busy with this page anymore
and decremented the refcnt. The page reuse algorithm in this case should
be good to reuse the page but given the old refcnt it will not do so and
attempt to release the page via page_frag_cache_drain() with
pagecnt_bias used as an arg. This in turn will result in negative refcnt
on struct page, which was initially observed by Xu Du.

Therefore, move the page count storage from ice_get_rx_buf() to a place
where we are sure that whole frame has been collected, but before
calling XDP program as it internally can also change the page count of
fragments belonging to xdp_buff.

Fixes: ac0753391195 ("ice: Store page count inside ice_rx_buf")
Reported-and-tested-by: Xu Du &lt;xudu@redhat.com&gt;
Reviewed-by: Przemek Kitszel &lt;przemyslaw.kitszel@intel.com&gt;
Reviewed-by: Simon Horman &lt;horms@kernel.org&gt;
Co-developed-by: Jacob Keller &lt;jacob.e.keller@intel.com&gt;
Signed-off-by: Jacob Keller &lt;jacob.e.keller@intel.com&gt;
Signed-off-by: Maciej Fijalkowski &lt;maciej.fijalkowski@intel.com&gt;
Tested-by: Chandan Kumar Rout &lt;chandanx.rout@intel.com&gt; (A Contingent Worker at Intel)
Signed-off-by: Tony Nguyen &lt;anthony.l.nguyen@intel.com&gt;
</content>
</entry>
<entry>
<title>ice: put Rx buffers after being done with current frame</title>
<updated>2025-01-31T17:51:47Z</updated>
<author>
<name>Maciej Fijalkowski</name>
<email>maciej.fijalkowski@intel.com</email>
</author>
<published>2025-01-23T15:01:16Z</published>
<link rel='alternate' type='text/html' href='https://git.kobert.dev/pm24.git/commit/?id=743bbd93cf29f653fae0e1416a31f03231689911'/>
<id>urn:sha1:743bbd93cf29f653fae0e1416a31f03231689911</id>
<content type='text'>
Introduce a new helper ice_put_rx_mbuf() that will go through gathered
frags from current frame and will call ice_put_rx_buf() on them. Current
logic that was supposed to simplify and optimize the driver where we go
through a batch of all buffers processed in current NAPI instance turned
out to be broken for jumbo frames and very heavy load that was coming
from both multi-thread iperf and nginx/wrk pair between server and
client. The delay introduced by approach that we are dropping is simply
too big and we need to take the decision regarding page
recycling/releasing as quick as we can.

While at it, address an error path of ice_add_xdp_frag() - we were
missing buffer putting from day 1 there.

As a nice side effect we get rid of annoying and repetitive three-liner:

	xdp-&gt;data = NULL;
	rx_ring-&gt;first_desc = ntc;
	rx_ring-&gt;nr_frags = 0;

by embedding it within introduced routine.

Fixes: 1dc1a7e7f410 ("ice: Centrallize Rx buffer recycling")
Reported-and-tested-by: Xu Du &lt;xudu@redhat.com&gt;
Reviewed-by: Przemek Kitszel &lt;przemyslaw.kitszel@intel.com&gt;
Reviewed-by: Simon Horman &lt;horms@kernel.org&gt;
Co-developed-by: Jacob Keller &lt;jacob.e.keller@intel.com&gt;
Signed-off-by: Jacob Keller &lt;jacob.e.keller@intel.com&gt;
Signed-off-by: Maciej Fijalkowski &lt;maciej.fijalkowski@intel.com&gt;
Tested-by: Chandan Kumar Rout &lt;chandanx.rout@intel.com&gt; (A Contingent Worker at Intel)
Signed-off-by: Tony Nguyen &lt;anthony.l.nguyen@intel.com&gt;
</content>
</entry>
<entry>
<title>iavf: allow changing VLAN state without calling PF</title>
<updated>2025-01-24T18:52:09Z</updated>
<author>
<name>Michal Swiatkowski</name>
<email>michal.swiatkowski@linux.intel.com</email>
</author>
<published>2024-09-05T09:14:10Z</published>
<link rel='alternate' type='text/html' href='https://git.kobert.dev/pm24.git/commit/?id=ee7d79433d783346430ee32f28c9df44a88b3bb6'/>
<id>urn:sha1:ee7d79433d783346430ee32f28c9df44a88b3bb6</id>
<content type='text'>
First case:
&gt; ip l a l $VF name vlanx type vlan id 100
&gt; ip l d vlanx
&gt; ip l a l $VF name vlanx type vlan id 100

As workqueue can be execute after sometime, there is a window to have
call trace like that:
- iavf_del_vlan
- iavf_add_vlan
- iavf_del_vlans (wq)

It means that our VLAN 100 will change the state from IAVF_VLAN_ACTIVE
to IAVF_VLAN_REMOVE (iavf_del_vlan). After that in iavf_add_vlan state
won't be changed because VLAN 100 is on the filter list. The final
result is that the VLAN 100 filter isn't added in hardware (no
iavf_add_vlans call).

To fix that change the state if the filter wasn't removed yet directly
to active. It is save as IAVF_VLAN_REMOVE means that virtchnl message
wasn't sent yet.

Second case:
&gt; ip l a l $VF name vlanx type vlan id 100
Any type of VF reset ex. change trust
&gt; ip l s $PF vf $VF_NUM trust on
&gt; ip l d vlanx
&gt; ip l a l $VF name vlanx type vlan id 100

In case of reset iavf driver is responsible for readding all filters
that are being used. To do that all VLAN filters state are changed to
IAVF_VLAN_ADD. Here is even longer window for changing VLAN state from
kernel side, as workqueue isn't called immediately. We can have call
trace like that:

- changing to IAVF_VLAN_ADD (after reset)
- iavf_del_vlan (called from kernel ops)
- iavf_del_vlans (wq)

Not exsisitng VLAN filters will be removed from hardware. It isn't a
bug, ice driver will handle it fine. However, we can have call trace
like that:

- changing to IAVF_VLAN_ADD (after reset)
- iavf_del_vlan (called from kernel ops)
- iavf_add_vlan (called from kernel ops)
- iavf_del_vlans (wq)

With fix for previous case we end up with no VLAN filters in hardware.
We have to remove VLAN filters if the state is IAVF_VLAN_ADD and delete
VLAN was called. It is save as IAVF_VLAN_ADD means that virtchnl message
wasn't sent yet.

Fixes: 0c0da0e95105 ("iavf: refactor VLAN filter states")
Signed-off-by: Michal Swiatkowski &lt;michal.swiatkowski@linux.intel.com&gt;
Reviewed-by: Przemek Kitszel &lt;przemyslaw.kitszel@intel.com&gt;
Tested-by: Rafal Romanowski &lt;rafal.romanowski@intel.com&gt;
Signed-off-by: Tony Nguyen &lt;anthony.l.nguyen@intel.com&gt;
</content>
</entry>
<entry>
<title>ice: remove invalid parameter of equalizer</title>
<updated>2025-01-24T18:49:42Z</updated>
<author>
<name>Mateusz Polchlopek</name>
<email>mateusz.polchlopek@intel.com</email>
</author>
<published>2024-12-31T09:50:44Z</published>
<link rel='alternate' type='text/html' href='https://git.kobert.dev/pm24.git/commit/?id=c5cc2a27e04f2fcd77c74ada9aef76a758a24697'/>
<id>urn:sha1:c5cc2a27e04f2fcd77c74ada9aef76a758a24697</id>
<content type='text'>
It occurred that in the commit 70838938e89c ("ice: Implement driver
functionality to dump serdes equalizer values") the invalid DRATE parameter
for reading has been added. The output of the command:

  $ ethtool -d &lt;ethX&gt;

returns the garbage value in the place where DRATE value should be
stored.

Remove mentioned parameter to prevent return of corrupted data to
userspace.

Fixes: 70838938e89c ("ice: Implement driver functionality to dump serdes equalizer values")
Signed-off-by: Mateusz Polchlopek &lt;mateusz.polchlopek@intel.com&gt;
Reviewed-by: Michal Swiatkowski &lt;michal.swiatkowski@linux.intel.com&gt;
Tested-by: Rinitha S &lt;sx.rinitha@intel.com&gt; (A Contingent worker at Intel)
Signed-off-by: Tony Nguyen &lt;anthony.l.nguyen@intel.com&gt;
</content>
</entry>
<entry>
<title>ice: fix ice_parser_rt::bst_key array size</title>
<updated>2025-01-24T18:49:30Z</updated>
<author>
<name>Przemek Kitszel</name>
<email>przemyslaw.kitszel@intel.com</email>
</author>
<published>2024-12-19T11:55:16Z</published>
<link rel='alternate' type='text/html' href='https://git.kobert.dev/pm24.git/commit/?id=18625e26fefced78f2ae28b25e80a07079821e04'/>
<id>urn:sha1:18625e26fefced78f2ae28b25e80a07079821e04</id>
<content type='text'>
Fix &amp;ice_parser_rt::bst_key size. It was wrongly set to 10 instead of 20
in the initial impl commit (see Fixes tag). All usage code assumed it was
of size 20. That was also the initial size present up to v2 of the intro
series [2], but halved by v3 [3] refactor described as "Replace magic
hardcoded values with macros." The introducing series was so big that
some ugliness was unnoticed, same for bugs :/

ICE_BST_KEY_TCAM_SIZE and ICE_BST_TCAM_KEY_SIZE were differing by one.
There was tmp variable @j in the scope of edited function, but was not
used in all places. This ugliness is now gone.
I'm moving ice_parser_rt::pg_prio a few positions up, to fill up one of
the holes in order to compensate for the added 10 bytes to the ::bst_key,
resulting in the same size of the whole as prior to the fix, and minimal
changes in the offsets of the fields.

Extend also the debug dump print of the key to cover all bytes. To not
have string with 20 "%02x" and 20 params, switch to
ice_debug_array_w_prefix().

This fix obsoletes Ahmed's attempt at [1].

[1] https://lore.kernel.org/intel-wired-lan/20240823230847.172295-1-ahmed.zaki@intel.com
[2] https://lore.kernel.org/intel-wired-lan/20230605054641.2865142-13-junfeng.guo@intel.com
[3] https://lore.kernel.org/intel-wired-lan/20230817093442.2576997-13-junfeng.guo@intel.com

Reported-by: Dan Carpenter &lt;dan.carpenter@linaro.org&gt;
Closes: https://lore.kernel.org/intel-wired-lan/b1fb6ff9-b69e-4026-9988-3c783d86c2e0@stanley.mountain
Fixes: 9a4c07aaa0f5 ("ice: add parser execution main loop")
CC: Ahmed Zaki &lt;ahmed.zaki@intel.com&gt;
Reviewed-by: Larysa Zaremba &lt;larysa.zaremba@intel.com&gt;
Signed-off-by: Przemek Kitszel &lt;przemyslaw.kitszel@intel.com&gt;
Reviewed-by: Simon Horman &lt;horms@kernel.org&gt;
Tested-by: Rafal Romanowski &lt;rafal.romanowski@intel.com&gt;
Signed-off-by: Tony Nguyen &lt;anthony.l.nguyen@intel.com&gt;
</content>
</entry>
<entry>
<title>idpf: add more info during virtchnl transaction timeout/salt mismatch</title>
<updated>2025-01-24T18:03:39Z</updated>
<author>
<name>Manoj Vishwanathan</name>
<email>manojvishy@google.com</email>
</author>
<published>2024-12-16T16:27:35Z</published>
<link rel='alternate' type='text/html' href='https://git.kobert.dev/pm24.git/commit/?id=d0ea9ebac3e7a5b53bc259e51f54043aa98696ad'/>
<id>urn:sha1:d0ea9ebac3e7a5b53bc259e51f54043aa98696ad</id>
<content type='text'>
Add more information related to the transaction like cookie, vc_op,
salt when transaction times out and include similar information
when transaction salt does not match.

Info output for transaction timeout:
-------------------
(op:5015 cookie:45fe vc_op:5015 salt:45 timeout:60000ms)
-------------------

before it was:

-------------------
(op 5015, 60000ms)
-------------------

Signed-off-by: Manoj Vishwanathan &lt;manojvishy@google.com&gt;
Signed-off-by: Brian Vazquez &lt;brianvv@google.com&gt;
Reviewed-by: Jacob Keller &lt;jacob.e.keller@intel.com&gt;
Reviewed-by: Pavan Kumar Linga &lt;pavan.kumar.linga@intel.com&gt;
Reviewed-by: Paul Menzel &lt;pmenzel@molgen.mpg.de&gt;
Tested-by: Krishneil Singh &lt;krishneil.k.singh@intel.com&gt;
Signed-off-by: Tony Nguyen &lt;anthony.l.nguyen@intel.com&gt;
</content>
</entry>
<entry>
<title>idpf: convert workqueues to unbound</title>
<updated>2025-01-24T18:03:39Z</updated>
<author>
<name>Marco Leogrande</name>
<email>leogrande@google.com</email>
</author>
<published>2024-12-16T16:27:34Z</published>
<link rel='alternate' type='text/html' href='https://git.kobert.dev/pm24.git/commit/?id=9a5b021cb8186f1854bac2812bd4f396bb1e881c'/>
<id>urn:sha1:9a5b021cb8186f1854bac2812bd4f396bb1e881c</id>
<content type='text'>
When a workqueue is created with `WQ_UNBOUND`, its work items are
served by special worker-pools, whose host workers are not bound to
any specific CPU. In the default configuration (i.e. when
`queue_delayed_work` and friends do not specify which CPU to run the
work item on), `WQ_UNBOUND` allows the work item to be executed on any
CPU in the same node of the CPU it was enqueued on. While this
solution potentially sacrifices locality, it avoids contention with
other processes that might dominate the CPU time of the processor the
work item was scheduled on.

This is not just a theoretical problem: in a particular scenario
misconfigured process was hogging most of the time from CPU0, leaving
less than 0.5% of its CPU time to the kworker. The IDPF workqueues
that were using the kworker on CPU0 suffered large completion delays
as a result, causing performance degradation, timeouts and eventual
system crash.

Tested:

* I have also run a manual test to gauge the performance
  improvement. The test consists of an antagonist process
  (`./stress --cpu 2`) consuming as much of CPU 0 as possible. This
  process is run under `taskset 01` to bind it to CPU0, and its
  priority is changed with `chrt -pQ 9900 10000 ${pid}` and
  `renice -n -20 ${pid}` after start.

  Then, the IDPF driver is forced to prefer CPU0 by editing all calls
  to `queue_delayed_work`, `mod_delayed_work`, etc... to use CPU 0.

  Finally, `ktraces` for the workqueue events are collected.

  Without the current patch, the antagonist process can force
  arbitrary delays between `workqueue_queue_work` and
  `workqueue_execute_start`, that in my tests were as high as
  `30ms`. With the current patch applied, the workqueue can be
  migrated to another unloaded CPU in the same node, and, keeping
  everything else equal, the maximum delay I could see was `6us`.

Fixes: 0fe45467a104 ("idpf: add create vport and netdev configuration")
Signed-off-by: Marco Leogrande &lt;leogrande@google.com&gt;
Signed-off-by: Manoj Vishwanathan &lt;manojvishy@google.com&gt;
Signed-off-by: Brian Vazquez &lt;brianvv@google.com&gt;
Reviewed-by: Jacob Keller &lt;jacob.e.keller@intel.com&gt;
Reviewed-by: Pavan Kumar Linga &lt;pavan.kumar.linga@intel.com&gt;
Tested-by: Krishneil Singh &lt;krishneil.k.singh@intel.com&gt;
Signed-off-by: Tony Nguyen &lt;anthony.l.nguyen@intel.com&gt;
</content>
</entry>
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