summaryrefslogtreecommitdiff
path: root/net/core/page_pool.c
AgeCommit message (Collapse)Author
2025-01-30Merge tag 'net-6.14-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net Pull networking fixes from Jakub Kicinski: "Including fixes from IPSec, netfilter and Bluetooth. Nothing really stands out, but as usual there's a slight concentration of fixes for issues added in the last two weeks before the merge window, and driver bugs from 6.13 which tend to get discovered upon wider distribution. Current release - regressions: - net: revert RTNL changes in unregister_netdevice_many_notify() - Bluetooth: fix possible infinite recursion of btusb_reset - eth: adjust locking in some old drivers which protect their state with spinlocks to avoid sleeping in atomic; core protects netdev state with a mutex now Previous releases - regressions: - eth: - mlx5e: make sure we pass node ID, not CPU ID to kvzalloc_node() - bgmac: reduce max frame size to support just 1500 bytes; the jumbo frame support would previously cause OOB writes, but now fails outright - mptcp: blackhole only if 1st SYN retrans w/o MPC is accepted, avoid false detection of MPTCP blackholing Previous releases - always broken: - mptcp: handle fastopen disconnect correctly - xfrm: - make sure skb->sk is a full sock before accessing its fields - fix taking a lock with preempt disabled for RT kernels - usb: ipheth: improve safety of packet metadata parsing; prevent potential OOB accesses - eth: renesas: fix missing rtnl lock in suspend/resume path" * tag 'net-6.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (88 commits) MAINTAINERS: add Neal to TCP maintainers net: revert RTNL changes in unregister_netdevice_many_notify() net: hsr: fix fill_frame_info() regression vs VLAN packets doc: mptcp: sysctl: blackhole_timeout is per-netns mptcp: blackhole only if 1st SYN retrans w/o MPC is accepted netfilter: nf_tables: reject mismatching sum of field_len with set key length net: sh_eth: Fix missing rtnl lock in suspend/resume path net: ravb: Fix missing rtnl lock in suspend/resume path selftests/net: Add test for loading devbound XDP program in generic mode net: xdp: Disallow attaching device-bound programs in generic mode tcp: correct handling of extreme memory squeeze bgmac: reduce max frame size to support just MTU 1500 vsock/test: Add test for connect() retries vsock/test: Add test for UAF due to socket unbinding vsock/test: Introduce vsock_connect_fd() vsock/test: Introduce vsock_bind() vsock: Allow retrying on connect() failure vsock: Keep the binding until socket destruction Bluetooth: L2CAP: accept zero as a special value for MTU auto-selection Bluetooth: btnxpuart: Fix glitches seen in dual A2DP streaming ...
2025-01-27net: page_pool: don't try to stash the napi idJakub Kicinski
Page ppol tried to cache the NAPI ID in page pool info to avoid having a dependency on the life cycle of the NAPI instance. Since commit under Fixes the NAPI ID is not populated until napi_enable() and there's a good chance that page pool is created before NAPI gets enabled. Protect the NAPI pointer with the existing page pool mutex, the reading path already holds it. napi_id itself we need to READ_ONCE(), it's protected by netdev_lock() which are not holding in page pool. Before this patch napi IDs were missing for mlx5: # ./cli.py --spec netlink/specs/netdev.yaml --dump page-pool-get [{'id': 144, 'ifindex': 2, 'inflight': 3072, 'inflight-mem': 12582912}, {'id': 143, 'ifindex': 2, 'inflight': 5568, 'inflight-mem': 22806528}, {'id': 142, 'ifindex': 2, 'inflight': 5120, 'inflight-mem': 20971520}, {'id': 141, 'ifindex': 2, 'inflight': 4992, 'inflight-mem': 20447232}, ... After: [{'id': 144, 'ifindex': 2, 'inflight': 3072, 'inflight-mem': 12582912, 'napi-id': 565}, {'id': 143, 'ifindex': 2, 'inflight': 4224, 'inflight-mem': 17301504, 'napi-id': 525}, {'id': 142, 'ifindex': 2, 'inflight': 4288, 'inflight-mem': 17563648, 'napi-id': 524}, ... Fixes: 86e25f40aa1e ("net: napi: Add napi_config") Reviewed-by: Mina Almasry <almasrymina@google.com> Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com> Link: https://patch.msgid.link/20250123231620.1086401-1-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-01-26Merge tag 'mm-stable-2025-01-26-14-59' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: "The various patchsets are summarized below. Plus of course many indivudual patches which are described in their changelogs. - "Allocate and free frozen pages" from Matthew Wilcox reorganizes the page allocator so we end up with the ability to allocate and free zero-refcount pages. So that callers (ie, slab) can avoid a refcount inc & dec - "Support large folios for tmpfs" from Baolin Wang teaches tmpfs to use large folios other than PMD-sized ones - "Fix mm/rodata_test" from Petr Tesarik performs some maintenance and fixes for this small built-in kernel selftest - "mas_anode_descend() related cleanup" from Wei Yang tidies up part of the mapletree code - "mm: fix format issues and param types" from Keren Sun implements a few minor code cleanups - "simplify split calculation" from Wei Yang provides a few fixes and a test for the mapletree code - "mm/vma: make more mmap logic userland testable" from Lorenzo Stoakes continues the work of moving vma-related code into the (relatively) new mm/vma.c - "mm/page_alloc: gfp flags cleanups for alloc_contig_*()" from David Hildenbrand cleans up and rationalizes handling of gfp flags in the page allocator - "readahead: Reintroduce fix for improper RA window sizing" from Jan Kara is a second attempt at fixing a readahead window sizing issue. It should reduce the amount of unnecessary reading - "synchronously scan and reclaim empty user PTE pages" from Qi Zheng addresses an issue where "huge" amounts of pte pagetables are accumulated: https://lore.kernel.org/lkml/cover.1718267194.git.zhengqi.arch@bytedance.com/ Qi's series addresses this windup by synchronously freeing PTE memory within the context of madvise(MADV_DONTNEED) - "selftest/mm: Remove warnings found by adding compiler flags" from Muhammad Usama Anjum fixes some build warnings in the selftests code when optional compiler warnings are enabled - "mm: don't use __GFP_HARDWALL when migrating remote pages" from David Hildenbrand tightens the allocator's observance of __GFP_HARDWALL - "pkeys kselftests improvements" from Kevin Brodsky implements various fixes and cleanups in the MM selftests code, mainly pertaining to the pkeys tests - "mm/damon: add sample modules" from SeongJae Park enhances DAMON to estimate application working set size - "memcg/hugetlb: Rework memcg hugetlb charging" from Joshua Hahn provides some cleanups to memcg's hugetlb charging logic - "mm/swap_cgroup: remove global swap cgroup lock" from Kairui Song removes the global swap cgroup lock. A speedup of 10% for a tmpfs-based kernel build was demonstrated - "zram: split page type read/write handling" from Sergey Senozhatsky has several fixes and cleaups for zram in the area of zram_write_page(). A watchdog softlockup warning was eliminated - "move pagetable_*_dtor() to __tlb_remove_table()" from Kevin Brodsky cleans up the pagetable destructor implementations. A rare use-after-free race is fixed - "mm/debug: introduce and use VM_WARN_ON_VMG()" from Lorenzo Stoakes simplifies and cleans up the debugging code in the VMA merging logic - "Account page tables at all levels" from Kevin Brodsky cleans up and regularizes the pagetable ctor/dtor handling. This results in improvements in accounting accuracy - "mm/damon: replace most damon_callback usages in sysfs with new core functions" from SeongJae Park cleans up and generalizes DAMON's sysfs file interface logic - "mm/damon: enable page level properties based monitoring" from SeongJae Park increases the amount of information which is presented in response to DAMOS actions - "mm/damon: remove DAMON debugfs interface" from SeongJae Park removes DAMON's long-deprecated debugfs interfaces. Thus the migration to sysfs is completed - "mm/hugetlb: Refactor hugetlb allocation resv accounting" from Peter Xu cleans up and generalizes the hugetlb reservation accounting - "mm: alloc_pages_bulk: small API refactor" from Luiz Capitulino removes a never-used feature of the alloc_pages_bulk() interface - "mm/damon: extend DAMOS filters for inclusion" from SeongJae Park extends DAMOS filters to support not only exclusion (rejecting), but also inclusion (allowing) behavior - "Add zpdesc memory descriptor for zswap.zpool" from Alex Shi introduces a new memory descriptor for zswap.zpool that currently overlaps with struct page for now. This is part of the effort to reduce the size of struct page and to enable dynamic allocation of memory descriptors - "mm, swap: rework of swap allocator locks" from Kairui Song redoes and simplifies the swap allocator locking. A speedup of 400% was demonstrated for one workload. As was a 35% reduction for kernel build time with swap-on-zram - "mm: update mips to use do_mmap(), make mmap_region() internal" from Lorenzo Stoakes reworks MIPS's use of mmap_region() so that mmap_region() can be made MM-internal - "mm/mglru: performance optimizations" from Yu Zhao fixes a few MGLRU regressions and otherwise improves MGLRU performance - "Docs/mm/damon: add tuning guide and misc updates" from SeongJae Park updates DAMON documentation - "Cleanup for memfd_create()" from Isaac Manjarres does that thing - "mm: hugetlb+THP folio and migration cleanups" from David Hildenbrand provides various cleanups in the areas of hugetlb folios, THP folios and migration - "Uncached buffered IO" from Jens Axboe implements the new RWF_DONTCACHE flag which provides synchronous dropbehind for pagecache reading and writing. To permite userspace to address issues with massive buildup of useless pagecache when reading/writing fast devices - "selftests/mm: virtual_address_range: Reduce memory" from Thomas Weißschuh fixes and optimizes some of the MM selftests" * tag 'mm-stable-2025-01-26-14-59' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (321 commits) mm/compaction: fix UBSAN shift-out-of-bounds warning s390/mm: add missing ctor/dtor on page table upgrade kasan: sw_tags: use str_on_off() helper in kasan_init_sw_tags() tools: add VM_WARN_ON_VMG definition mm/damon/core: use str_high_low() helper in damos_wmark_wait_us() seqlock: add missing parameter documentation for raw_seqcount_try_begin() mm/page-writeback: consolidate wb_thresh bumping logic into __wb_calc_thresh mm/page_alloc: remove the incorrect and misleading comment zram: remove zcomp_stream_put() from write_incompressible_page() mm: separate move/undo parts from migrate_pages_batch() mm/kfence: use str_write_read() helper in get_access_type() selftests/mm/mkdirty: fix memory leak in test_uffdio_copy() kasan: hw_tags: Use str_on_off() helper in kasan_init_hw_tags() selftests/mm: virtual_address_range: avoid reading from VM_IO mappings selftests/mm: vm_util: split up /proc/self/smaps parsing selftests/mm: virtual_address_range: unmap chunks after validation selftests/mm: virtual_address_range: mmap() without PROT_WRITE selftests/memfd/memfd_test: fix possible NULL pointer dereference mm: add FGP_DONTCACHE folio creation flag mm: call filemap_fdatawrite_range_kick() after IOCB_DONTCACHE issue ...
2025-01-25mm: alloc_pages_bulk: rename APILuiz Capitulino
The previous commit removed the page_list argument from alloc_pages_bulk_noprof() along with the alloc_pages_bulk_list() function. Now that only the *_array() flavour of the API remains, we can do the following renaming (along with the _noprof() ones): alloc_pages_bulk_array -> alloc_pages_bulk alloc_pages_bulk_array_mempolicy -> alloc_pages_bulk_mempolicy alloc_pages_bulk_array_node -> alloc_pages_bulk_node Link: https://lkml.kernel.org/r/275a3bbc0be20fbe9002297d60045e67ab3d4ada.1734991165.git.luizcap@redhat.com Signed-off-by: Luiz Capitulino <luizcap@redhat.com> Acked-by: David Hildenbrand <david@redhat.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Yunsheng Lin <linyunsheng@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-01-16selftests: drv-net-hw: inject pp_alloc_fail errors in the right placeJohn Daley
The tool pp_alloc_fail.py tested error recovery by injecting errors into the function page_pool_alloc_pages(). The page pool allocation function page_pool_dev_alloc() does not end up calling page_pool_alloc_pages(). page_pool_alloc_netmems() seems to be the function that is called by all of the page pool alloc functions in the API, so move error injection to that function instead. Signed-off-by: John Daley <johndale@cisco.com> Link: https://patch.msgid.link/20250115181312.3544-2-johndale@cisco.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-12-17net: page_pool: rename page_pool_is_last_ref()Jakub Kicinski
page_pool_is_last_ref() releases a reference while the name, to me at least, suggests it just checks if the refcount is 1. The semantics of the function are the same as those of atomic_dec_and_test() and refcount_dec_and_test(), so just use the _and_test() suffix. Reviewed-by: Alexander Lobakin <aleksander.lobakin@intel.com> Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org> Acked-by: Jesper Dangaard Brouer <hawk@kernel.org> Link: https://patch.msgid.link/20241215212938.99210-1-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-12-12page_pool: disable sync for cpu for dmabuf memory providerMina Almasry
dmabuf dma-addresses should not be dma_sync'd for CPU/device. Typically its the driver responsibility to dma_sync for CPU, but the driver should not dma_sync for CPU if the netmem is actually coming from a dmabuf memory provider. The page_pool already exposes a helper for dma_sync_for_cpu: page_pool_dma_sync_for_cpu. Upgrade this existing helper to handle netmem, and have it skip dma_sync if the memory is from a dmabuf memory provider. Drivers should migrate to using this helper when adding support for netmem. Also minimize the impact on the dma syncing performance for pages. Special case the dma-sync path for pages to not go through the overhead checks for dma-syncing and conversion to netmem. Cc: Alexander Lobakin <aleksander.lobakin@intel.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Signed-off-by: Mina Almasry <almasrymina@google.com> Link: https://patch.msgid.link/20241211212033.1684197-5-almasrymina@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-12-12page_pool: Set `dma_sync` to false for devmem memory providerSamiullah Khawaja
Move the `dma_map` and `dma_sync` checks to `page_pool_init` to make them generic. Set dma_sync to false for devmem memory provider because the dma_sync APIs should not be used for dma_buf backed devmem memory provider. Cc: Jason Gunthorpe <jgg@ziepe.ca> Signed-off-by: Samiullah Khawaja <skhawaja@google.com> Signed-off-by: Mina Almasry <almasrymina@google.com> Link: https://patch.msgid.link/20241211212033.1684197-4-almasrymina@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-12-12net: page_pool: rename page_pool_alloc_netmem to *_netmemsMina Almasry
page_pool_alloc_netmem (without an s) was the mirror of page_pool_alloc_pages (with an s), which was confusing. Rename to page_pool_alloc_netmems so it's the mirror of page_pool_alloc_pages. Signed-off-by: Mina Almasry <almasrymina@google.com> Acked-by: Stanislav Fomichev <sdf@fomichev.me> Link: https://patch.msgid.link/20241211212033.1684197-2-almasrymina@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-12-12page_pool: allow mixing PPs within one bulkAlexander Lobakin
The main reason for this change was to allow mixing pages from different &page_pools within one &xdp_buff/&xdp_frame. Why not? With stuff like devmem and io_uring zerocopy Rx, it's required to have separate PPs for header buffers and payload buffers. Adjust xdp_return_frame_bulk() and page_pool_put_netmem_bulk(), so that they won't be tied to a particular pool. Let the latter create a separate bulk of pages which's PP is different from the first netmem of the bulk and process it after the main loop. This greatly optimizes xdp_return_frame_bulk(): no more hashtable lookups and forced flushes on PP mismatch. Also make xdp_flush_frame_bulk() inline, as it's just one if + function call + one u32 read, not worth extending the call ladder. Co-developed-by: Toke Høiland-Jørgensen <toke@redhat.com> # iterative Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com> Suggested-by: Jakub Kicinski <kuba@kernel.org> # while (count) Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com> Link: https://patch.msgid.link/20241211172649.761483-2-aleksander.lobakin@intel.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-12-05page_pool: make page_pool_put_page_bulk() handle array of netmemsAlexander Lobakin
Currently, page_pool_put_page_bulk() indeed takes an array of pointers to the data, not pages, despite the name. As one side effect, when you're freeing frags from &skb_shared_info, xdp_return_frame_bulk() converts page pointers to virtual addresses and then page_pool_put_page_bulk() converts them back. Moreover, data pointers assume every frag is placed in the host memory, making this function non-universal. Make page_pool_put_page_bulk() handle array of netmems. Pass frag netmems directly and use virt_to_netmem() when freeing xdpf->data, so that the PP core will then get the compound netmem and take care of the rest. Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com> Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com> Link: https://patch.msgid.link/20241203173733.3181246-9-aleksander.lobakin@intel.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-11-12net: page_pool: do not count normal frag allocation in statsJakub Kicinski
Commit 0f6deac3a079 ("net: page_pool: add page allocation stats for two fast page allocate path") added increments for "fast path" allocation to page frag alloc. It mentions performance degradation analysis but the details are unclear. Could be that the author was simply surprised by the alloc stats not matching packet count. In my experience the key metric for page pool is the recycling rate. Page return stats, however, count returned _pages_ not frags. This makes it impossible to calculate recycling rate for drivers using the frag API. Here is example output of the page-pool YNL sample for a driver allocating 1200B frags (4k pages) with nearly perfect recycling: $ ./page-pool eth0[2] page pools: 32 (zombies: 0) refs: 291648 bytes: 1194590208 (refs: 0 bytes: 0) recycling: 33.3% (alloc: 4557:2256365862 recycle: 200476245:551541893) The recycling rate is reported as 33.3% because we give out 4096 // 1200 = 3 frags for every recycled page. Effectively revert the aforementioned commit. This also aligns with the stats we would see for drivers which do the fragmentation themselves, although that's not a strong reason in itself. On the (very unlikely) path where we can reuse the current page let's bump the "cached" stat. The fact that we don't put the page in the cache is just an optimization. Acked-by: Jesper Dangaard Brouer <hawk@kernel.org> Reviewed-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com> Acked-by: Ilias Apalodimas <ilias.apalodimas@linaro.org> Link: https://patch.msgid.link/20241109023303.3366500-1-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-09-11memory-provider: dmabuf devmem memory providerMina Almasry
Implement a memory provider that allocates dmabuf devmem in the form of net_iov. The provider receives a reference to the struct netdev_dmabuf_binding via the pool->mp_priv pointer. The driver needs to set this pointer for the provider in the net_iov. The provider obtains a reference on the netdev_dmabuf_binding which guarantees the binding and the underlying mapping remains alive until the provider is destroyed. Usage of PP_FLAG_DMA_MAP is required for this memory provide such that the page_pool can provide the driver with the dma-addrs of the devmem. Support for PP_FLAG_DMA_SYNC_DEV is omitted for simplicity & p.order != 0. Signed-off-by: Willem de Bruijn <willemb@google.com> Signed-off-by: Kaiyuan Zhang <kaiyuanz@google.com> Signed-off-by: Mina Almasry <almasrymina@google.com> Reviewed-by: Pavel Begunkov <asml.silence@gmail.com> Reviewed-by: Jakub Kicinski <kuba@kernel.org> Link: https://patch.msgid.link/20240910171458.219195-7-almasrymina@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-09-11page_pool: devmem supportMina Almasry
Convert netmem to be a union of struct page and struct netmem. Overload the LSB of struct netmem* to indicate that it's a net_iov, otherwise it's a page. Currently these entries in struct page are rented by the page_pool and used exclusively by the net stack: struct { unsigned long pp_magic; struct page_pool *pp; unsigned long _pp_mapping_pad; unsigned long dma_addr; atomic_long_t pp_ref_count; }; Mirror these (and only these) entries into struct net_iov and implement netmem helpers that can access these common fields regardless of whether the underlying type is page or net_iov. Implement checks for net_iov in netmem helpers which delegate to mm APIs, to ensure net_iov are never passed to the mm stack. Signed-off-by: Mina Almasry <almasrymina@google.com> Reviewed-by: Pavel Begunkov <asml.silence@gmail.com> Acked-by: Jakub Kicinski <kuba@kernel.org> Link: https://patch.msgid.link/20240910171458.219195-6-almasrymina@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-07-10page_pool: use __cacheline_group_{begin, end}_aligned()Alexander Lobakin
Instead of doing __cacheline_group_begin() __aligned(), use the new __cacheline_group_{begin,end}_aligned(), so that it will take care of the group alignment itself. Also replace open-coded `4 * sizeof(long)` in two places with a definition. Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com> Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
2024-07-08net: page_pool: fix warning codeJohannes Berg
WARN_ON_ONCE("string") doesn't really do what appears to be intended, so fix that. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Fixes: 90de47f020db ("page_pool: fragment API support for 32-bit arch with 64-bit DMA") Link: https://patch.msgid.link/20240705134221.2f4de205caa1.I28496dc0f2ced580282d1fb892048017c4491e21@changeid Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-07-02page_pool: convert to use netmemMina Almasry
Abstract the memory type from the page_pool so we can later add support for new memory types. Convert the page_pool to use the new netmem type abstraction, rather than use struct page directly. As of this patch the netmem type is a no-op abstraction: it's always a struct page underneath. All the page pool internals are converted to use struct netmem instead of struct page, and the page pool now exports 2 APIs: 1. The existing struct page API. 2. The new struct netmem API. Keeping the existing API is transitional; we do not want to refactor all the current drivers using the page pool at once. The netmem abstraction is currently a no-op. The page_pool uses page_to_netmem() to convert allocated pages to netmem, and uses netmem_to_page() to convert the netmem back to pages to pass to mm APIs, Follow up patches to this series add non-paged netmem support to the page_pool. This change is factored out on its own to limit the code churn to this 1 patch, for ease of code review. Signed-off-by: Mina Almasry <almasrymina@google.com> Reviewed-by: Pavel Begunkov <asml.silence@gmail.com> Link: https://patch.msgid.link/20240628003253.1694510-6-almasrymina@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-07-02page_pool: export page_pool_disable_direct_recycling()David Wei
56ef27e3 unexported page_pool_unlink_napi() and renamed it to page_pool_disable_direct_recycling(). This is because there was no in-tree user of page_pool_unlink_napi(). Since then Rx queue API and an implementation in bnxt got merged. In the bnxt implementation, it broadly follows the following steps: allocate new queue memory + page pool, stop old rx queue, swap, then destroy old queue memory + page pool. The existing NAPI instance is re-used so when the old page pool that is no longer used but still linked to this shared NAPI instance is destroyed, it will trigger warnings. In my initial patches I unlinked a page pool from a NAPI instance directly. Instead, export page_pool_disable_direct_recycling() and call that instead to avoid having a driver touch a core struct. Suggested-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: David Wei <dw@davidwei.uk> Reviewed-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-06-09page_pool: remove WARN_ON() with ORDavid Wei
Having an OR in WARN_ON() makes me sad because it's impossible to tell which condition is true when triggered. Split a WARN_ON() with an OR in page_pool_disable_direct_recycling(). Signed-off-by: David Wei <dw@davidwei.uk> Reviewed-by: Mina Almasry <almasrymina@google.com> Reviewed-by: Somnath Kotur <somnath.kotur@broadcom.com> Acked-by: Jesper Dangaard Brouer <hawk@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2024-05-20Merge tag 'dma-mapping-6.10-2024-05-20' of ↵Linus Torvalds
git://git.infradead.org/users/hch/dma-mapping Pull dma-mapping updates from Christoph Hellwig: - optimize DMA sync calls when they are no-ops (Alexander Lobakin) - fix swiotlb padding for untrusted devices (Michael Kelley) - add documentation for swiotb (Michael Kelley) * tag 'dma-mapping-6.10-2024-05-20' of git://git.infradead.org/users/hch/dma-mapping: dma: fix DMA sync for drivers not calling dma_set_mask*() xsk: use generic DMA sync shortcut instead of a custom one page_pool: check for DMA sync shortcut earlier page_pool: don't use driver-set flags field directly page_pool: make sure frag API fields don't span between cachelines iommu/dma: avoid expensive indirect calls for sync operations dma: avoid redundant calls for sync operations dma: compile-out DMA sync op calls when not used iommu/dma: fix zeroing of bounce buffer padding used by untrusted devices swiotlb: remove alloc_size argument to swiotlb_tbl_map_single() Documentation/core-api: add swiotlb documentation
2024-05-08page_pool: check for DMA sync shortcut earlierAlexander Lobakin
We can save a couple more function calls in the Page Pool code if we check for dma_need_sync() earlier, just when we test pp->p.dma_sync. Move both these checks into an inline wrapper and call the PP wrapper over the generic DMA sync function only when both are true. You can't cache the result of dma_need_sync() in &page_pool, as it may change anytime if an SWIOTLB buffer is allocated or mapped. Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2024-05-07page_pool: don't use driver-set flags field directlyAlexander Lobakin
page_pool::p is driver-defined params, copied directly from the structure passed to page_pool_create(). The structure isn't meant to be modified by the Page Pool core code and this even might look confusing[0][1]. In order to be able to alter some flags, let's define our own, internal fields the same way as the already existing one (::has_init_callback). They are defined as bits in the driver-set params, leave them so here as well, to not waste byte-per-bit or so. Almost 30 bits are still free for future extensions. We could've defined only new flags here or only the ones we may need to alter, but checking some flags in one place while others in another doesn't sound convenient or intuitive. ::flags passed by the driver can now go to the "slow" PP params. Suggested-by: Jakub Kicinski <kuba@kernel.org> Link[0]: https://lore.kernel.org/netdev/20230703133207.4f0c54ce@kernel.org Suggested-by: Alexander Duyck <alexanderduyck@fb.com> Link[1]: https://lore.kernel.org/netdev/CAKgT0UfZCGnWgOH96E4GV3ZP6LLbROHM7SHE8NKwq+exX+Gk_Q@mail.gmail.com Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2024-05-07page_pool: make sure frag API fields don't span between cachelinesAlexander Lobakin
After commit 5027ec19f104 ("net: page_pool: split the page_pool_params into fast and slow") that made &page_pool contain only "hot" params at the start, cacheline boundary chops frag API fields group in the middle again. To not bother with this each time fast params get expanded or shrunk, let's just align them to `4 * sizeof(long)`, the closest upper pow-2 to their actual size (2 longs + 1 int). This ensures 16-byte alignment for the 32-bit architectures and 32-byte alignment for the 64-bit ones, excluding unnecessary false-sharing. ::page_state_hold_cnt is used quite intensively on hotpath no matter if frag API is used, so move it to the newly created hole in the first cacheline. Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2024-04-30net: page_pool: support error injectionJakub Kicinski
Because of caching / recycling using the general page allocation failures to induce errors in page pool allocation is very hard. Add direct error injection support to page_pool_alloc_pages(). Reviewed-by: Willem de Bruijn <willemb@google.com> Link: https://lore.kernel.org/r/20240429144426.743476-2-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-04-24page_pool: constify some read-only function argumentsAlexander Lobakin
There are several functions taking pointers to data they don't modify. This includes statistics fetching, page and page_pool parameters, etc. Constify the pointers, so that call sites will be able to pass const pointers as well. No functional changes, no visible changes in functions sizes. Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org> Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com> Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
2024-04-02page_pool: try direct bulk recyclingAlexander Lobakin
Now that the checks for direct recycling possibility live inside the Page Pool core, reuse them when performing bulk recycling. page_pool_put_page_bulk() can be called from process context as well, page_pool_napi_local() takes care of this at the very beginning. Under high .ndo_xdp_xmit() traffic load, the win is 2-3% Pps assuming the sending driver uses xdp_return_frame_bulk() on Tx completion. Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com> Link: https://lore.kernel.org/r/20240329165507.3240110-3-aleksander.lobakin@intel.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-04-02page_pool: check for PP direct cache locality laterAlexander Lobakin
Since we have pool->p.napi (Jakub) and pool->cpuid (Lorenzo) to check whether it's safe to use direct recycling, we can use both globally for each page instead of relying solely on @allow_direct argument. Let's assume that @allow_direct means "I'm sure it's local, don't waste time rechecking this" and when it's false, try the mentioned params to still recycle the page directly. If neither is true, we'll lose some CPU cycles, but then it surely won't be hotpath. On the other hand, paths where it's possible to use direct cache, but not possible to safely set @allow_direct, will benefit from this move. The whole propagation of @napi_safe through a dozen of skb freeing functions can now go away, which saves us some stack space. Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com> Link: https://lore.kernel.org/r/20240329165507.3240110-2-aleksander.lobakin@intel.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-03-11net: page_pool: factor out page_pool recycle checkMina Almasry
The check is duplicated in 2 places, factor it out into a common helper. Signed-off-by: Mina Almasry <almasrymina@google.com> Reviewed-by: Yunsheng Lin <linyunsheng@huawei.com> Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org> Link: https://lore.kernel.org/r/20240308204500.1112858-1-almasrymina@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-02-19net: page_pool: fix recycle stats for system page_pool allocatorLorenzo Bianconi
Use global percpu page_pool_recycle_stats counter for system page_pool allocator instead of allocating a separate percpu variable for each (also percpu) page pool instance. Reviewed-by: Toke Hoiland-Jorgensen <toke@redhat.com> Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org> Reviewed-by: Alexander Lobakin <aleksander.lobakin@intel.com> Link: https://lore.kernel.org/r/87f572425e98faea3da45f76c3c68815c01a20ee.1708075412.git.lorenzo@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-02-19page_pool: disable direct recycling based on pool->cpuid on destroyAlexander Lobakin
Now that direct recycling is performed basing on pool->cpuid when set, memory leaks are possible: 1. A pool is destroyed. 2. Alloc cache is emptied (it's done only once). 3. pool->cpuid is still set. 4. napi_pp_put_page() does direct recycling basing on pool->cpuid. 5. Now alloc cache is not empty, but it won't ever be freed. In order to avoid that, rewrite pool->cpuid to -1 when unlinking NAPI to make sure no direct recycling will be possible after emptying the cache. This involves a bit of overhead as pool->cpuid now must be accessed via READ_ONCE() to avoid partial reads. Rename page_pool_unlink_napi() -> page_pool_disable_direct_recycling() to reflect what it actually does and unexport it. Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com> Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com> Link: https://lore.kernel.org/r/20240215113905.96817-1-aleksander.lobakin@intel.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-02-13net: add generic percpu page_pool allocatorLorenzo Bianconi
Introduce generic percpu page_pools allocator. Moreover add page_pool_create_percpu() and cpuid filed in page_pool struct in order to recycle the page in the page_pool "hot" cache if napi_pp_put_page() is running on the same cpu. This is a preliminary patch to add xdp multi-buff support for xdp running in generic mode. Acked-by: Jesper Dangaard Brouer <hawk@kernel.org> Reviewed-by: Toke Hoiland-Jorgensen <toke@redhat.com> Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org> Link: https://lore.kernel.org/r/80bc4285228b6f4220cd03de1999d86e46e3fcbd.1707729884.git.lorenzo@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-12-17page_pool: halve BIAS_MAX for multiple user references of a fragmentLiang Chen
Up to now, we were only subtracting from the number of used page fragments to figure out when a page could be freed or recycled. A following patch introduces support for multiple users referencing the same fragment. So reduce the initial page fragments value to half to avoid overflowing. Signed-off-by: Liang Chen <liangchen.linux@gmail.com> Reviewed-by: Yunsheng Lin <linyunsheng@huawei.com> Reviewed-by: Mina Almasry <almarsymina@google.com> Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-12-13net: page_pool: factor out releasing DMA from releasing the pageJakub Kicinski
Releasing the DMA mapping will be useful for other types of pages, so factor it out. Make sure compiler inlines it, to avoid any regressions. Signed-off-by: Mina Almasry <almasrymina@google.com> Reviewed-by: Shakeel Butt <shakeelb@google.com> Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-12-13page_pool: transition to reference count management after page drainingLiang Chen
To support multiple users referencing the same fragment, 'pp_frag_count' is renamed to 'pp_ref_count', transitioning pp pages from fragment management to reference count management after draining based on the suggestion from [1]. The idea is that the concept of fragmenting exists before the page is drained, and all related functions retain their current names. However, once the page is drained, its management shifts to being governed by 'pp_ref_count'. Therefore, all functions associated with that lifecycle stage of a pp page are renamed. [1] http://lore.kernel.org/netdev/f71d9448-70c8-8793-dc9a-0eb48a570300@huawei.com Signed-off-by: Liang Chen <liangchen.linux@gmail.com> Reviewed-by: Yunsheng Lin <linyunsheng@huawei.com> Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org> Reviewed-by: Mina Almasry <almasrymina@google.com> Link: https://lore.kernel.org/r/20231212044614.42733-2-liangchen.linux@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-11-28net: page_pool: mute the periodic warning for visible page poolsJakub Kicinski
Mute the periodic "stalled pool shutdown" warning if the page pool is visible to user space. Rolling out a driver using page pools to just a few hundred hosts at Meta surfaces applications which fail to reap their broken sockets. Obviously it's best if the applications are fixed, but we don't generally print warnings for application resource leaks. Admins can now depend on the netlink interface for getting page pool info to detect buggy apps. While at it throw in the ID of the pool into the message, in rare cases (pools from destroyed netns) this will make finding the pool with a debugger easier. Reviewed-by: Eric Dumazet <edumazet@google.com> Acked-by: Jesper Dangaard Brouer <hawk@kernel.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-11-28net: page_pool: expose page pool stats via netlinkJakub Kicinski
Dump the stats into netlink. More clever approaches like dumping the stats per-CPU for each CPU individually to see where the packets get consumed can be implemented in the future. A trimmed example from a real (but recently booted system): $ ./cli.py --no-schema --spec netlink/specs/netdev.yaml \ --dump page-pool-stats-get [{'info': {'id': 19, 'ifindex': 2}, 'alloc-empty': 48, 'alloc-fast': 3024, 'alloc-refill': 0, 'alloc-slow': 48, 'alloc-slow-high-order': 0, 'alloc-waive': 0, 'recycle-cache-full': 0, 'recycle-cached': 0, 'recycle-released-refcnt': 0, 'recycle-ring': 0, 'recycle-ring-full': 0}, {'info': {'id': 18, 'ifindex': 2}, 'alloc-empty': 66, 'alloc-fast': 11811, 'alloc-refill': 35, 'alloc-slow': 66, 'alloc-slow-high-order': 0, 'alloc-waive': 0, 'recycle-cache-full': 1145, 'recycle-cached': 6541, 'recycle-released-refcnt': 0, 'recycle-ring': 1275, 'recycle-ring-full': 0}, {'info': {'id': 17, 'ifindex': 2}, 'alloc-empty': 73, 'alloc-fast': 62099, 'alloc-refill': 413, ... Acked-by: Jesper Dangaard Brouer <hawk@kernel.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-11-28net: page_pool: report when page pool was destroyedJakub Kicinski
Report when page pool was destroyed. Together with the inflight / memory use reporting this can serve as a replacement for the warning about leaked page pools we currently print to dmesg. Example output for a fake leaked page pool using some hacks in netdevsim (one "live" pool, and one "leaked" on the same dev): $ ./cli.py --no-schema --spec netlink/specs/netdev.yaml \ --dump page-pool-get [{'id': 2, 'ifindex': 3}, {'id': 1, 'ifindex': 3, 'destroyed': 133, 'inflight': 1}] Tested-by: Dragos Tatulea <dtatulea@nvidia.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Acked-by: Jesper Dangaard Brouer <hawk@kernel.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-11-28net: page_pool: report amount of memory held by page poolsJakub Kicinski
Advanced deployments need the ability to check memory use of various system components. It makes it possible to make informed decisions about memory allocation and to find regressions and leaks. Report memory use of page pools. Report both number of references and bytes held. Acked-by: Jesper Dangaard Brouer <hawk@kernel.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-11-28net: page_pool: id the page poolsJakub Kicinski
To give ourselves the flexibility of creating netlink commands and ability to refer to page pool instances in uAPIs create IDs for page pools. Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org> Reviewed-by: Eric Dumazet <edumazet@google.com> Acked-by: Jesper Dangaard Brouer <hawk@kernel.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Reviewed-by: Shakeel Butt <shakeelb@google.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-11-28net: page_pool: factor out uninitJakub Kicinski
We'll soon (next change in the series) need a fuller unwind path in page_pool_create() so create the inverse of page_pool_init(). Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org> Reviewed-by: Eric Dumazet <edumazet@google.com> Acked-by: Jesper Dangaard Brouer <hawk@kernel.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Reviewed-by: Shakeel Butt <shakeelb@google.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-11-21net: page_pool: avoid touching slow on the fastpathJakub Kicinski
To fully benefit from previous commit add one byte of state in the first cache line recording if we need to look at the slow part. The packing isn't all that impressive right now, we create a 7B hole. I'm expecting Olek's rework will reshuffle this, anyway. Acked-by: Jesper Dangaard Brouer <hawk@kernel.org> Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org> Reviewed-by: Mina Almasry <almasrymina@google.com> Link: https://lore.kernel.org/r/20231121000048.789613-3-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-11-21net: page_pool: split the page_pool_params into fast and slowJakub Kicinski
struct page_pool is rather performance critical and we use 16B of the first cache line to store 2 pointers used only by test code. Future patches will add more informational (non-fast path) attributes. It's convenient for the user of the API to not have to worry which fields are fast and which are slow path. Use struct groups to split the params into the two categories internally. Acked-by: Jesper Dangaard Brouer <hawk@kernel.org> Reviewed-by: Mina Almasry <almasrymina@google.com> Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org> Link: https://lore.kernel.org/r/20231121000048.789613-2-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-11-02net: page_pool: add missing free_percpu when page_pool_init failJian Shen
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>
2023-10-23page_pool: introduce page_pool_alloc() APIYunsheng Lin
Currently page pool supports the below use cases: use case 1: allocate page without page splitting using page_pool_alloc_pages() API if the driver knows that the memory it need is always bigger than half of the page allocated from page pool. use case 2: allocate page frag with page splitting using page_pool_alloc_frag() API if the driver knows that the memory it need is always smaller than or equal to the half of the page allocated from page pool. There is emerging use case [1] & [2] that is a mix of the above two case: the driver doesn't know the size of memory it need beforehand, so the driver may use something like below to allocate memory with least memory utilization and performance penalty: if (size << 1 > max_size) page = page_pool_alloc_pages(); else page = page_pool_alloc_frag(); To avoid the driver doing something like above, add the page_pool_alloc() API to support the above use case, and update the true size of memory that is acctually allocated by updating '*size' back to the driver in order to avoid exacerbating truesize underestimate problem. Rename page_pool_free() which is used in the destroy process to __page_pool_destroy() to avoid confusion with the newly added API. 1. https://lore.kernel.org/all/d3ae6bd3537fbce379382ac6a42f67e22f27ece2.1683896626.git.lorenzo@kernel.org/ 2. https://lore.kernel.org/all/20230526054621.18371-3-liangchen.linux@gmail.com/ Signed-off-by: Yunsheng Lin <linyunsheng@huawei.com> CC: Lorenzo Bianconi <lorenzo@kernel.org> CC: Alexander Duyck <alexander.duyck@gmail.com> CC: Liang Chen <liangchen.linux@gmail.com> CC: Alexander Lobakin <aleksander.lobakin@intel.com> Link: https://lore.kernel.org/r/20231020095952.11055-4-linyunsheng@huawei.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-10-23page_pool: remove PP_FLAG_PAGE_FRAGYunsheng Lin
PP_FLAG_PAGE_FRAG is not really needed after pp_frag_count handling is unified and page_pool_alloc_frag() is supported in 32-bit arch with 64-bit DMA, so remove it. Signed-off-by: Yunsheng Lin <linyunsheng@huawei.com> CC: Lorenzo Bianconi <lorenzo@kernel.org> CC: Alexander Duyck <alexander.duyck@gmail.com> CC: Liang Chen <liangchen.linux@gmail.com> CC: Alexander Lobakin <aleksander.lobakin@intel.com> Link: https://lore.kernel.org/r/20231020095952.11055-3-linyunsheng@huawei.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-10-23page_pool: unify frag_count handling in page_pool_is_last_frag()Yunsheng Lin
Currently when page_pool_create() is called with PP_FLAG_PAGE_FRAG flag, page_pool_alloc_pages() is only allowed to be called under the below constraints: 1. page_pool_fragment_page() need to be called to setup page->pp_frag_count immediately. 2. page_pool_defrag_page() often need to be called to drain the page->pp_frag_count when there is no more user will be holding on to that page. Those constraints exist in order to support a page to be split into multi fragments. And those constraints have some overhead because of the cache line dirtying/bouncing and atomic update. Those constraints are unavoidable for case when we need a page to be split into more than one fragment, but there is also case that we want to avoid the above constraints and their overhead when a page can't be split as it can only hold a fragment as requested by user, depending on different use cases: use case 1: allocate page without page splitting. use case 2: allocate page with page splitting. use case 3: allocate page with or without page splitting depending on the fragment size. Currently page pool only provide page_pool_alloc_pages() and page_pool_alloc_frag() API to enable the 1 & 2 separately, so we can not use a combination of 1 & 2 to enable 3, it is not possible yet because of the per page_pool flag PP_FLAG_PAGE_FRAG. So in order to allow allocating unsplit page without the overhead of split page while still allow allocating split page we need to remove the per page_pool flag in page_pool_is_last_frag(), as best as I can think of, it seems there are two methods as below: 1. Add per page flag/bit to indicate a page is split or not, which means we might need to update that flag/bit everytime the page is recycled, dirtying the cache line of 'struct page' for use case 1. 2. Unify the page->pp_frag_count handling for both split and unsplit page by assuming all pages in the page pool is split into a big fragment initially. As page pool already supports use case 1 without dirtying the cache line of 'struct page' whenever a page is recyclable, we need to support the above use case 3 with minimal overhead, especially not adding any noticeable overhead for use case 1, and we are already doing an optimization by not updating pp_frag_count in page_pool_defrag_page() for the last fragment user, this patch chooses to unify the pp_frag_count handling to support the above use case 3. There is no noticeable performance degradation and some justification for unifying the frag_count handling with this patch applied using a micro-benchmark testing in [1]. 1. https://lore.kernel.org/all/bf2591f8-7b3c-4480-bb2c-31dc9da1d6ac@huawei.com/ Signed-off-by: Yunsheng Lin <linyunsheng@huawei.com> CC: Lorenzo Bianconi <lorenzo@kernel.org> CC: Alexander Duyck <alexander.duyck@gmail.com> CC: Liang Chen <liangchen.linux@gmail.com> CC: Alexander Lobakin <aleksander.lobakin@intel.com> Link: https://lore.kernel.org/r/20231020095952.11055-2-linyunsheng@huawei.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-10-16page_pool: fragment API support for 32-bit arch with 64-bit DMAYunsheng Lin
Currently page_pool_alloc_frag() is not supported in 32-bit arch with 64-bit DMA because of the overlap issue between pp_frag_count and dma_addr_upper in 'struct page' for those arches, which seems to be quite common, see [1], which means driver may need to handle it when using fragment API. It is assumed that the combination of the above arch with an address space >16TB does not exist, as all those arches have 64b equivalent, it seems logical to use the 64b version for a system with a large address space. It is also assumed that dma address is page aligned when we are dma mapping a page aligned buffer, see [2]. That means we're storing 12 bits of 0 at the lower end for a dma address, we can reuse those bits for the above arches to support 32b+12b, which is 16TB of memory. If we make a wrong assumption, a warning is emitted so that user can report to us. 1. https://lore.kernel.org/all/20211117075652.58299-1-linyunsheng@huawei.com/ 2. https://lore.kernel.org/all/20230818145145.4b357c89@kernel.org/ Tested-by: Alexander Lobakin <aleksander.lobakin@intel.com> Signed-off-by: Yunsheng Lin <linyunsheng@huawei.com> CC: Lorenzo Bianconi <lorenzo@kernel.org> CC: Alexander Duyck <alexander.duyck@gmail.com> CC: Liang Chen <liangchen.linux@gmail.com> CC: Guillaume Tucker <guillaume.tucker@collabora.com> CC: Matthew Wilcox <willy@infradead.org> CC: Linux-MM <linux-mm@kvack.org> Link: https://lore.kernel.org/r/20231013064827.61135-2-linyunsheng@huawei.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-08-07page_pool: add a lockdep check for recycling in hardirqJakub Kicinski
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>
2023-08-07net: skbuff: don't include <net/page_pool/types.h> to <linux/skbuff.h>Alexander Lobakin
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>
2023-08-07page_pool: split types and declarations from page_pool.hYunsheng Lin
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>