net: page_pool: add missing free_percpu when page_pool_init fail

[ Upstream commit 8ffbd1669ed1d58939d6e878dffaa2f60bf961a4 ]

When ptr_ring_init() returns failure in page_pool_init(), free_percpu()

net: page_pool: add missing free_percpu when page_pool_init fail

[ Upstream commit 8ffbd1669ed1d58939d6e878dffaa2f60bf961a4 ]

When ptr_ring_init() returns failure in page_pool_init(), free_percpu()
is not called to free pool->recycle_stats, which may cause memory
leak.

Fixes: ad6fa1e1ab1b ("page_pool: Add recycle stats")
Signed-off-by: Jian Shen <shenjian15@huawei.com>
Signed-off-by: Jijie Shao <shaojijie@huawei.com>
Reviewed-by: Yunsheng Lin <linyunsheng@huawei.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Reviewed-by: Somnath Kotur <somnath.kotur@broadcom.com>
Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Link: https://lore.kernel.org/r/20231030091256.2915394-1-shaojijie@huawei.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

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page_pool: add a lockdep check for recycling in hardirq

Page pool use in hardirq is prohibited, add debug checks
to catch misuses. IIRC we previously discussed using
DEBUG_NET_WARN_ON_ONCE() for thi

page_pool: add a lockdep check for recycling in hardirq

Page pool use in hardirq is prohibited, add debug checks
to catch misuses. IIRC we previously discussed using
DEBUG_NET_WARN_ON_ONCE() for this, but there were concerns
that people will have DEBUG_NET enabled in perf testing.
I don't think anyone enables lockdep in perf testing,
so use lockdep to avoid pushback and arguing :)

Acked-by: Jesper Dangaard Brouer <hawk@kernel.org>
Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Reviewed-by: Alexander Duyck <alexanderduyck@fb.com>
Link: https://lore.kernel.org/r/20230804180529.2483231-6-aleksander.lobakin@intel.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

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net: skbuff: don't include <net/page_pool/types.h> to <linux/skbuff.h>

Currently, touching <net/page_pool/types.h> triggers a rebuild of more
than half of the kernel. That's because it's included in

net: skbuff: don't include <net/page_pool/types.h> to <linux/skbuff.h>

Currently, touching <net/page_pool/types.h> triggers a rebuild of more
than half of the kernel. That's because it's included in
<linux/skbuff.h>. And each new include to page_pool/types.h adds more
[useless] data for the toolchain to process per each source file from
that pile.

In commit 6a5bcd84e886 ("page_pool: Allow drivers to hint on SKB
recycling"), Matteo included it to be able to call a couple of functions
defined there. Then, in commit 57f05bc2ab24 ("page_pool: keep pp info as
long as page pool owns the page") one of the calls was removed, so only
one was left. It's the call to page_pool_return_skb_page() in
napi_frag_unref(). The function is external and doesn't have any
dependencies. Having very niche page_pool_types.h included only for that
looks like an overkill.

As %PP_SIGNATURE is not local to page_pool.c (was only in the
early submissions), nothing holds this function there. Teleport
page_pool_return_skb_page() to skbuff.c, just next to the main consumer,
skb_pp_recycle(), and rename it to napi_pp_put_page(), as it doesn't
work with skbs at all and the former name tells nothing. The #if guards
here are only to not compile and have it in the vmlinux when not needed
-- both call sites are already guarded.
Now, touching page_pool_types.h only triggers rebuilding of the drivers
using it and a couple of core networking files.

Suggested-by: Jakub Kicinski <kuba@kernel.org> # make skbuff.h less heavy
Suggested-by: Alexander Duyck <alexanderduyck@fb.com> # move to skbuff.c
Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Reviewed-by: Alexander Duyck <alexanderduyck@fb.com>
Link: https://lore.kernel.org/r/20230804180529.2483231-3-aleksander.lobakin@intel.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

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page_pool: split types and declarations from page_pool.h

Split types and pure function declarations from page_pool.h
and add them in page_page/types.h, so that C sources can
include page_pool.h and

page_pool: split types and declarations from page_pool.h

Split types and pure function declarations from page_pool.h
and add them in page_page/types.h, so that C sources can
include page_pool.h and headers should generally only include
page_pool/types.h as suggested by jakub.
Rename page_pool.h to page_pool/helpers.h to have both in
one place.

Signed-off-by: Yunsheng Lin <linyunsheng@huawei.com>
Suggested-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Reviewed-by: Alexander Duyck <alexanderduyck@fb.com>
Link: https://lore.kernel.org/r/20230804180529.2483231-2-aleksander.lobakin@intel.com
[Jakub: change microsoft/mana, fix kdoc paths in Documentation]
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

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docs: net: page_pool: use kdoc to avoid duplicating the information

All struct members of the driver-facing APIs are documented twice,
in the code and under Documentation. This is a bit tedious.

I

docs: net: page_pool: use kdoc to avoid duplicating the information

All struct members of the driver-facing APIs are documented twice,
in the code and under Documentation. This is a bit tedious.

I also get the feeling that a lot of developers will read the header
when coding, rather than the doc. Bring the two a little closer
together by using kdoc for structs and functions.

Using kdoc also gives us links (mentioning a function or struct
in the text gets replaced by a link to its doc).

Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Jesper Dangaard Brouer <hawk@kernel.org>
Link: https://lore.kernel.org/r/20230802161821.3621985-3-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

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net: page_pool: merge page_pool_release_page() with page_pool_return_page()

Now that page_pool_release_page() is not exported we can
merge it with page_pool_return_page(). I believe that
the "Do not

net: page_pool: merge page_pool_release_page() with page_pool_return_page()

Now that page_pool_release_page() is not exported we can
merge it with page_pool_return_page(). I believe that
the "Do not replace this with page_pool_return_page()"
comment was there in case page_pool_return_page() was
not inlined, to avoid two function calls.

Acked-by: Jesper Dangaard Brouer <hawk@kernel.org>
Reviewed-by: Yunsheng Lin <linyunsheng@huawei.com>
Link: https://lore.kernel.org/r/20230720010409.1967072-5-kuba@kernel.org
Reviewed-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

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net: page_pool: hide page_pool_release_page()

There seems to be no user calling page_pool_release_page()
for legit reasons, all the users simply haven't been converted
to skb-based recycling, yet. P

net: page_pool: hide page_pool_release_page()

There seems to be no user calling page_pool_release_page()
for legit reasons, all the users simply haven't been converted
to skb-based recycling, yet. Previous changes converted them.
Update the docs, and unexport the function.

Link: https://lore.kernel.org/r/20230720010409.1967072-4-kuba@kernel.org
Reviewed-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

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page_pool: fix inconsistency for page_pool_ring_[un]lock()

page_pool_ring_[un]lock() use in_softirq() to decide which
spin lock variant to use, and when they are called in the
context with in_softir

page_pool: fix inconsistency for page_pool_ring_[un]lock()

page_pool_ring_[un]lock() use in_softirq() to decide which
spin lock variant to use, and when they are called in the
context with in_softirq() being false, spin_lock_bh() is
called in page_pool_ring_lock() while spin_unlock() is
called in page_pool_ring_unlock(), because spin_lock_bh()
has disabled the softirq in page_pool_ring_lock(), which
causes inconsistency for spin lock pair calling.

This patch fixes it by returning in_softirq state from
page_pool_producer_lock(), and use it to decide which
spin lock variant to use in page_pool_producer_unlock().

As pool->ring has both producer and consumer lock, so
rename it to page_pool_producer_[un]lock() to reflect
the actual usage. Also move them to page_pool.c as they
are only used there, and remove the 'inline' as the
compiler may have better idea to do inlining or not.

Fixes: 7886244736a4 ("net: page_pool: Add bulk support for ptr_ring")
Signed-off-by: Yunsheng Lin <linyunsheng@huawei.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Link: https://lore.kernel.org/r/20230522031714.5089-1-linyunsheng@huawei.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

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page_pool: unlink from napi during destroy

Jesper points out that we must prevent recycling into cache
after page_pool_destroy() is called, because page_pool_destroy()
is not synchronized with recyc

page_pool: unlink from napi during destroy

Jesper points out that we must prevent recycling into cache
after page_pool_destroy() is called, because page_pool_destroy()
is not synchronized with recycling (some pages may still be
outstanding when destroy() gets called).

I assumed this will not happen because NAPI can't be scheduled
if its page pool is being destroyed. But I missed the fact that
NAPI may get reused. For instance when user changes ring configuration
driver may allocate a new page pool, stop NAPI, swap, start NAPI,
and then destroy the old pool. The NAPI is running so old page
pool will think it can recycle to the cache, but the consumer
at that point is the destroy() path, not NAPI.

To avoid extra synchronization let the drivers do "unlinking"
during the "swap" stage while NAPI is indeed disabled.

Fixes: 8c48eea3adf3 ("page_pool: allow caching from safely localized NAPI")
Reported-by: Jesper Dangaard Brouer <jbrouer@redhat.com>
Link: https://lore.kernel.org/all/e8df2654-6a5b-3c92-489d-2fe5e444135f@redhat.com/
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Link: https://lore.kernel.org/r/20230419182006.719923-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

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page_pool: add DMA_ATTR_WEAK_ORDERING on all mappings

Commit c519fe9a4f0d ("bnxt: add dma mapping attributes") added
DMA_ATTR_WEAK_ORDERING to DMA attrs on bnxt. It has since spread
to a few more dr

page_pool: add DMA_ATTR_WEAK_ORDERING on all mappings

Commit c519fe9a4f0d ("bnxt: add dma mapping attributes") added
DMA_ATTR_WEAK_ORDERING to DMA attrs on bnxt. It has since spread
to a few more drivers (possibly as a copy'n'paste).

DMA_ATTR_WEAK_ORDERING only seems to matter on Sparc and PowerPC/cell,
the rarity of these platforms is likely why we never bothered adding
the attribute in the page pool, even though it should be safe to add.

To make the page pool migration in drivers which set this flag less
of a risk (of regressing the precious sparc database workloads or
whatever needed this) let's add DMA_ATTR_WEAK_ORDERING on all
page pool DMA mappings.

We could make this a driver opt-in but frankly I don't think it's
worth complicating the API. I can't think of a reason why device
accesses to packet memory would have to be ordered.

Acked-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Acked-by: Somnath Kotur <somnath.kotur@broadcom.com>
Reviewed-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Link: https://lore.kernel.org/r/20230417152805.331865-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

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page_pool: allow caching from safely localized NAPI

Recent patches to mlx5 mentioned a regression when moving from
driver local page pool to only using the generic page pool code.
Page pool has two

page_pool: allow caching from safely localized NAPI

Recent patches to mlx5 mentioned a regression when moving from
driver local page pool to only using the generic page pool code.
Page pool has two recycling paths (1) direct one, which runs in
safe NAPI context (basically consumer context, so producing
can be lockless); and (2) via a ptr_ring, which takes a spin
lock because the freeing can happen from any CPU; producer
and consumer may run concurrently.

Since the page pool code was added, Eric introduced a revised version
of deferred skb freeing. TCP skbs are now usually returned to the CPU
which allocated them, and freed in softirq context. This places the
freeing (producing of pages back to the pool) enticingly close to
the allocation (consumer).

If we can prove that we're freeing in the same softirq context in which
the consumer NAPI will run - lockless use of the cache is perfectly fine,
no need for the lock.

Let drivers link the page pool to a NAPI instance. If the NAPI instance
is scheduled on the same CPU on which we're freeing - place the pages
in the direct cache.

With that and patched bnxt (XDP enabled to engage the page pool, sigh,
bnxt really needs page pool work :() I see a 2.6% perf boost with
a TCP stream test (app on a different physical core than softirq).

The CPU use of relevant functions decreases as expected:

page_pool_refill_alloc_cache 1.17% -> 0%
_raw_spin_lock 2.41% -> 0.98%

Only consider lockless path to be safe when NAPI is scheduled
- in practice this should cover majority if not all of steady state
workloads. It's usually the NAPI kicking in that causes the skb flush.

The main case we'll miss out on is when application runs on the same
CPU as NAPI. In that case we don't use the deferred skb free path.

Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Tested-by: Dragos Tatulea <dtatulea@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

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net: page_pool: use in_softirq() instead

We use BH context only for synchronization, so we don't care if it's
actually serving softirq or not.

As a side node, in case of threaded NAPI, in_serving_s

net: page_pool: use in_softirq() instead

We use BH context only for synchronization, so we don't care if it's
actually serving softirq or not.

As a side node, in case of threaded NAPI, in_serving_softirq() will
return false because it's in process context with BH off, making
page_pool_recycle_in_cache() unreachable.

Signed-off-by: Qingfang DENG <qingfang.deng@siflower.com.cn>
Tested-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: David S. Miller <davem@davemloft.net>

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net: page_pool: optimize page pool page allocation in NUMA scenario

Currently NIC packet receiving performance based on page pool deteriorates
occasionally. To analysis the causes of this problem pa

net: page_pool: optimize page pool page allocation in NUMA scenario

Currently NIC packet receiving performance based on page pool deteriorates
occasionally. To analysis the causes of this problem page allocation stats
are collected. Here are the stats when NIC rx performance deteriorates:

bandwidth(Gbits/s) 16.8 6.91
rx_pp_alloc_fast 13794308 21141869
rx_pp_alloc_slow 108625 166481
rx_pp_alloc_slow_h 0 0
rx_pp_alloc_empty 8192 8192
rx_pp_alloc_refill 0 0
rx_pp_alloc_waive 100433 158289
rx_pp_recycle_cached 0 0
rx_pp_recycle_cache_full 0 0
rx_pp_recycle_ring 362400 420281
rx_pp_recycle_ring_full 6064893 9709724
rx_pp_recycle_released_ref 0 0

The rx_pp_alloc_waive count indicates that a large number of pages' numa
node are inconsistent with the NIC device numa node. Therefore these pages
can't be reused by the page pool. As a result, many new pages would be
allocated by __page_pool_alloc_pages_slow which is time consuming. This
causes the NIC rx performance fluctuations.

The main reason of huge numa mismatch pages in page pool is that page pool
uses alloc_pages_bulk_array to allocate original pages. This function is
not suitable for page allocation in NUMA scenario. So this patch uses
alloc_pages_bulk_array_node which has a NUMA id input parameter to ensure
the NUMA consistent between NIC device and allocated pages.

Repeated NIC rx performance tests are performed 40 times. NIC rx bandwidth
is higher and more stable compared to the datas above. Here are three test
stats, the rx_pp_alloc_waive count is zero and rx_pp_alloc_slow which
indicates pages allocated from slow patch is relatively low.

bandwidth(Gbits/s) 93 93.9 93.8
rx_pp_alloc_fast 60066264 61266386 60938254
rx_pp_alloc_slow 16512 16517 16539
rx_pp_alloc_slow_ho 0 0 0
rx_pp_alloc_empty 16512 16517 16539
rx_pp_alloc_refill 473841 481910 481585
rx_pp_alloc_waive 0 0 0
rx_pp_recycle_cached 0 0 0
rx_pp_recycle_cache_full 0 0 0
rx_pp_recycle_ring 29754145 30358243 30194023
rx_pp_recycle_ring_full 0 0 0
rx_pp_recycle_released_ref 0 0 0

Signed-off-by: Jie Wang <wangjie125@huawei.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Link: https://lore.kernel.org/r/20220705113515.54342-1-huangguangbin2@huawei.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

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mm/swap: convert __put_page() to __folio_put()

Saves 11 bytes of text by removing a check of PageTail.

Link: https://lkml.kernel.org/r/20220617175020.717127-16-willy@infradead.org
Signed-off-by: Ma

mm/swap: convert __put_page() to __folio_put()

Saves 11 bytes of text by removing a check of PageTail.

Link: https://lkml.kernel.org/r/20220617175020.717127-16-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

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net: page_pool: add page allocation stats for two fast page allocate path

Currently If use page pool allocation stats to analysis a RX performance
degradation problem. These stats only count for pag

net: page_pool: add page allocation stats for two fast page allocate path

Currently If use page pool allocation stats to analysis a RX performance
degradation problem. These stats only count for pages allocate from
page_pool_alloc_pages. But nic drivers such as hns3 use
page_pool_dev_alloc_frag to allocate pages, so page stats in this API
should also be counted.

Signed-off-by: Jie Wang <wangjie125@huawei.com>
Signed-off-by: Guangbin Huang <huangguangbin2@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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net: page_pool: introduce ethtool stats

Introduce page_pool APIs to report stats through ethtool and reduce
duplicated code in each driver.

Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Revi

net: page_pool: introduce ethtool stats

Introduce page_pool APIs to report stats through ethtool and reduce
duplicated code in each driver.

Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

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page_pool: Add recycle stats to page_pool_put_page_bulk

Add missing recycle stats to page_pool_put_page_bulk routine.

Reviewed-by: Joe Damato <jdamato@fastly.com>
Signed-off-by: Lorenzo Bianconi <l

page_pool: Add recycle stats to page_pool_put_page_bulk

Add missing recycle stats to page_pool_put_page_bulk routine.

Reviewed-by: Joe Damato <jdamato@fastly.com>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Link: https://lore.kernel.org/r/3712178b51c007cfaed910ea80e68f00c916b1fa.1649685634.git.lorenzo@kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

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page_pool: Add function to batch and return stats

Adds a function page_pool_get_stats which can be used by drivers to obtain
stats for a specified page_pool.

Signed-off-by: Joe Damato <jdamato@fast

page_pool: Add function to batch and return stats

Adds a function page_pool_get_stats which can be used by drivers to obtain
stats for a specified page_pool.

Signed-off-by: Joe Damato <jdamato@fastly.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

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page_pool: Add recycle stats

Add per-cpu stats tracking page pool recycling events:
- cached: recycling placed page in the page pool cache
- cache_full: page pool cache was full
- ring: page plac

page_pool: Add recycle stats

Add per-cpu stats tracking page pool recycling events:
- cached: recycling placed page in the page pool cache
- cache_full: page pool cache was full
- ring: page placed into the ptr ring
- ring_full: page released from page pool because the ptr ring was full
- released_refcnt: page released (and not recycled) because refcnt > 1

Signed-off-by: Joe Damato <jdamato@fastly.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

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page_pool: Add allocation stats

Add per-pool statistics counters for the allocation path of a page pool.
These stats are incremented in softirq context, so no locking or per-cpu
variables are needed

page_pool: Add allocation stats

Add per-pool statistics counters for the allocation path of a page pool.
These stats are incremented in softirq context, so no locking or per-cpu
variables are needed.

This code is disabled by default and a kernel config option is provided for
users who wish to enable them.

The statistics added are:
- fast: successful fast path allocations
- slow: slow path order-0 allocations
- slow_high_order: slow path high order allocations
- empty: ptr ring is empty, so a slow path allocation was forced.
- refill: an allocation which triggered a refill of the cache
- waive: pages obtained from the ptr ring that cannot be added to
the cache due to a NUMA mismatch.

Signed-off-by: Joe Damato <jdamato@fastly.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

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page_pool: Refactor page_pool to enable fragmenting after allocation

This change is meant to permit a driver to perform "fragmenting" of the
page from within the driver instead of the current model

page_pool: Refactor page_pool to enable fragmenting after allocation

This change is meant to permit a driver to perform "fragmenting" of the
page from within the driver instead of the current model which requires
pre-partitioning the page. The main motivation behind this is to support
use cases where the page will be split up by the driver after DMA instead
of before.

With this change it becomes possible to start using page pool to replace
some of the existing use cases where multiple references were being used
for a single page, but the number needed was unknown as the size could be
dynamic.

For example, with this code it would be possible to do something like
the following to handle allocation:
page = page_pool_alloc_pages();
if (!page)
return NULL;
page_pool_fragment_page(page, DRIVER_PAGECNT_BIAS_MAX);
rx_buf->page = page;
rx_buf->pagecnt_bias = DRIVER_PAGECNT_BIAS_MAX;

Then we would process a received buffer by handling it with:
rx_buf->pagecnt_bias--;

Once the page has been fully consumed we could then flush the remaining
instances with:
if (page_pool_defrag_page(page, rx_buf->pagecnt_bias))
continue;
page_pool_put_defragged_page(pool, page -1, !!budget);

The general idea is that we want to have the ability to allocate a page
with excess fragment count and then trim off the unneeded fragments.

Signed-off-by: Alexander Duyck <alexanderduyck@fb.com>
Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

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page_pool: remove spinlock in page_pool_refill_alloc_cache()

As page_pool_refill_alloc_cache() is only called by
__page_pool_get_cached(), which assumes non-concurrent access
as suggested by the com

page_pool: remove spinlock in page_pool_refill_alloc_cache()

As page_pool_refill_alloc_cache() is only called by
__page_pool_get_cached(), which assumes non-concurrent access
as suggested by the comment in __page_pool_get_cached(), and
ptr_ring allows concurrent access between consumer and producer,
so remove the spinlock in page_pool_refill_alloc_cache().

Signed-off-by: Yunsheng Lin <linyunsheng@huawei.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Link: https://lore.kernel.org/r/20220107090042.13605-1-linyunsheng@huawei.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

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page_pool: Store the XDP mem id

Store the XDP mem ID inside the page_pool struct so it can be retrieved
later for use in bpf_prog_run().

Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Sign

page_pool: Store the XDP mem id

Store the XDP mem ID inside the page_pool struct so it can be retrieved
later for use in bpf_prog_run().

Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Link: https://lore.kernel.org/bpf/20220103150812.87914-4-toke@redhat.com

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page_pool: Add callback to init pages when they are allocated

Add a new callback function to page_pool that, if set, will be called every
time a new page is allocated. This will be used from bpf_tes

page_pool: Add callback to init pages when they are allocated

Add a new callback function to page_pool that, if set, will be called every
time a new page is allocated. This will be used from bpf_test_run() to
initialise the page data with the data provided by userspace when running
XDP programs with redirect turned on.

Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Link: https://lore.kernel.org/bpf/20220103150812.87914-3-toke@redhat.com

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page_pool: Revert "page_pool: disable dma mapping support..."

This reverts commit d00e60ee54b12de945b8493cf18c1ada9e422514.

As reported by Guillaume in [1]:
Enabling LPAE always enables CONFIG_ARCH

page_pool: Revert "page_pool: disable dma mapping support..."

This reverts commit d00e60ee54b12de945b8493cf18c1ada9e422514.

As reported by Guillaume in [1]:
Enabling LPAE always enables CONFIG_ARCH_DMA_ADDR_T_64BIT
in 32-bit systems, which breaks the bootup proceess when a
ethernet driver is using page pool with PP_FLAG_DMA_MAP flag.
As we were hoping we had no active consumers for such system
when we removed the dma mapping support, and LPAE seems like
a common feature for 32 bits system, so revert it.

1. https://www.spinics.net/lists/netdev/msg779890.html

Fixes: d00e60ee54b1 ("page_pool: disable dma mapping support for 32-bit arch with 64-bit DMA")
Signed-off-by: Yunsheng Lin <linyunsheng@huawei.com>
Reported-by: "kernelci.org bot" <bot@kernelci.org>
Tested-by: "kernelci.org bot" <bot@kernelci.org>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

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