wireguard-linux/include/trace/events/xdp.h, branch jd/unified-crypt-queue

devmap: Adjust tracepoint for map-less queue flush

2020-01-17T04:03:34Z

Now that we don't have a reference to a devmap when flushing the device bulk queue, let's change the the devmap_xmit tracepoint to remote the map_id and map_index fields entirely. Rearrange the fields so 'drops' and 'sent' stay in the same position in the tracepoint struct, to make it possible for the xdp_monitor utility to read both the old and the new format. Signed-off-by: Jesper Dangaard Brouer Signed-off-by: Toke Høiland-Jørgensen Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/157918768613.1458396.9165902403373826572.stgit@toke.dk

xdp: Use bulking for non-map XDP_REDIRECT and consolidate code paths

2020-01-17T04:03:34Z

Since the bulk queue used by XDP_REDIRECT now lives in struct net_device, we can re-use the bulking for the non-map version of the bpf_redirect() helper. This is a simple matter of having xdp_do_redirect_slow() queue the frame on the bulk queue instead of sending it out with __bpf_tx_xdp(). Unfortunately we can't make the bpf_redirect() helper return an error if the ifindex doesn't exit (as bpf_redirect_map() does), because we don't have a reference to the network namespace of the ingress device at the time the helper is called. So we have to leave it as-is and keep the device lookup in xdp_do_redirect_slow(). Since this leaves less reason to have the non-map redirect code in a separate function, so we get rid of the xdp_do_redirect_slow() function entirely. This does lose us the tracepoint disambiguation, but fortunately the xdp_redirect and xdp_redirect_map tracepoints use the same tracepoint entry structures. This means both can contain a map index, so we can just amend the tracepoint definitions so we always emit the xdp_redirect(_err) tracepoints, but with the map ID only populated if a map is present. This means we retire the xdp_redirect_map(_err) tracepoints entirely, but keep the definitions around in case someone is still listening for them. With this change, the performance of the xdp_redirect sample program goes from 5Mpps to 8.4Mpps (a 68% increase). Since the flush functions are no longer map-specific, rename the flush() functions to drop _map from their names. One of the renamed functions is the xdp_do_flush_map() callback used in all the xdp-enabled drivers. To keep from having to update all drivers, use a #define to keep the old name working, and only update the virtual drivers in this patch. Signed-off-by: Toke Høiland-Jørgensen Signed-off-by: Alexei Starovoitov Acked-by: John Fastabend Link: https://lore.kernel.org/bpf/157918768505.1458396.17518057312953572912.stgit@toke.dk

xdp: Move devmap bulk queue into struct net_device

2020-01-17T04:03:34Z

Commit 96360004b862 ("xdp: Make devmap flush_list common for all map instances"), changed devmap flushing to be a global operation instead of a per-map operation. However, the queue structure used for bulking was still allocated as part of the containing map. This patch moves the devmap bulk queue into struct net_device. The motivation for this is reusing it for the non-map variant of XDP_REDIRECT, which will be changed in a subsequent commit. To avoid other fields of struct net_device moving to different cache lines, we also move a couple of other members around. We defer the actual allocation of the bulk queue structure until the NETDEV_REGISTER notification devmap.c. This makes it possible to check for ndo_xdp_xmit support before allocating the structure, which is not possible at the time struct net_device is allocated. However, we keep the freeing in free_netdev() to avoid adding another RCU callback on NETDEV_UNREGISTER. Because of this change, we lose the reference back to the map that originated the redirect, so change the tracepoint to always return 0 as the map ID and index. Otherwise no functional change is intended with this patch. After this patch, the relevant part of struct net_device looks like this, according to pahole: /* --- cacheline 14 boundary (896 bytes) --- */ struct netdev_queue * _tx __attribute__((__aligned__(64))); /* 896 8 */ unsigned int num_tx_queues; /* 904 4 */ unsigned int real_num_tx_queues; /* 908 4 */ struct Qdisc * qdisc; /* 912 8 */ unsigned int tx_queue_len; /* 920 4 */ spinlock_t tx_global_lock; /* 924 4 */ struct xdp_dev_bulk_queue * xdp_bulkq; /* 928 8 */ struct xps_dev_maps * xps_cpus_map; /* 936 8 */ struct xps_dev_maps * xps_rxqs_map; /* 944 8 */ struct mini_Qdisc * miniq_egress; /* 952 8 */ /* --- cacheline 15 boundary (960 bytes) --- */ struct hlist_head qdisc_hash[16]; /* 960 128 */ /* --- cacheline 17 boundary (1088 bytes) --- */ struct timer_list watchdog_timer; /* 1088 40 */ /* XXX last struct has 4 bytes of padding */ int watchdog_timeo; /* 1128 4 */ /* XXX 4 bytes hole, try to pack */ struct list_head todo_list; /* 1136 16 */ /* --- cacheline 18 boundary (1152 bytes) --- */ Signed-off-by: Toke Høiland-Jørgensen Signed-off-by: Alexei Starovoitov Acked-by: Björn Töpel Acked-by: John Fastabend Link: https://lore.kernel.org/bpf/157918768397.1458396.12673224324627072349.stgit@toke.dk

page_pool: do not release pool until inflight == 0.

2019-11-16T20:39:10Z

The page pool keeps track of the number of pages in flight, and it isn't safe to remove the pool until all pages are returned. Disallow removing the pool until all pages are back, so the pool is always available for page producers. Make the page pool responsible for its own delayed destruction instead of relying on XDP, so the page pool can be used without the xdp memory model. When all pages are returned, free the pool and notify xdp if the pool is registered with the xdp memory system. Have the callback perform a table walk since some drivers (cpsw) may share the pool among multiple xdp_rxq_info. Note that the increment of pages_state_release_cnt may result in inflight == 0, resulting in the pool being released. Fixes: d956a048cd3f ("xdp: force mem allocator removal and periodic warning") Signed-off-by: Jonathan Lemon Acked-by: Jesper Dangaard Brouer Acked-by: Ilias Apalodimas Signed-off-by: David S. Miller

xdp: Fix type of string pointer in __XDP_ACT_SYM_TAB

2019-10-22T19:39:54Z

The table entry in __XDP_ACT_SYM_TAB for the last item is set to { -1, 0 } where it should be { -1, NULL } as the second item is a pointer to a string. Fixes the following sparse warnings: ./include/trace/events/xdp.h:28:1: warning: Using plain integer as NULL pointer ./include/trace/events/xdp.h:53:1: warning: Using plain integer as NULL pointer ./include/trace/events/xdp.h:82:1: warning: Using plain integer as NULL pointer ./include/trace/events/xdp.h:140:1: warning: Using plain integer as NULL pointer ./include/trace/events/xdp.h:155:1: warning: Using plain integer as NULL pointer ./include/trace/events/xdp.h:190:1: warning: Using plain integer as NULL pointer ./include/trace/events/xdp.h:225:1: warning: Using plain integer as NULL pointer ./include/trace/events/xdp.h:260:1: warning: Using plain integer as NULL pointer ./include/trace/events/xdp.h:318:1: warning: Using plain integer as NULL pointer ./include/trace/events/xdp.h:356:1: warning: Using plain integer as NULL pointer ./include/trace/events/xdp.h:390:1: warning: Using plain integer as NULL pointer Signed-off-by: Ben Dooks (Codethink) Signed-off-by: Daniel Borkmann Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20191022125925.10508-1-ben.dooks@codethink.co.uk

xdp: Add devmap_hash map type for looking up devices by hashed index

2019-07-29T20:50:48Z

A common pattern when using xdp_redirect_map() is to create a device map where the lookup key is simply ifindex. Because device maps are arrays, this leaves holes in the map, and the map has to be sized to fit the largest ifindex, regardless of how many devices actually are actually needed in the map. This patch adds a second type of device map where the key is looked up using a hashmap, instead of being used as an array index. This allows maps to be densely packed, so they can be smaller. Signed-off-by: Toke Høiland-Jørgensen Acked-by: Yonghong Song Acked-by: Jesper Dangaard Brouer Signed-off-by: Alexei Starovoitov

bpf_xdp_redirect_map: Perform map lookup in eBPF helper

2019-06-28T23:31:09Z

The bpf_redirect_map() helper used by XDP programs doesn't return any indication of whether it can successfully redirect to the map index it was given. Instead, BPF programs have to track this themselves, leading to programs using duplicate maps to track which entries are populated in the devmap. This patch fixes this by moving the map lookup into the bpf_redirect_map() helper, which makes it possible to return failure to the eBPF program. The lower bits of the flags argument is used as the return code, which means that existing users who pass a '0' flag argument will get XDP_ABORTED. With this, a BPF program can check the return code from the helper call and react by, for instance, substituting a different redirect. This works for any type of map used for redirect. Signed-off-by: Toke Høiland-Jørgensen Acked-by: Jonathan Lemon Acked-by: Andrii Nakryiko Signed-off-by: Daniel Borkmann

xdp: Add tracepoint for bulk XDP_TX

2019-06-25T12:26:50Z

This is introduced for admins to check what is happening on XDP_TX when bulk XDP_TX is in use, which will be first introduced in veth in next commit. v3: - Add act field to be in line with other XDP tracepoints. Signed-off-by: Toshiaki Makita Acked-by: Jesper Dangaard Brouer Signed-off-by: Daniel Borkmann

xdp: add tracepoints for XDP mem

2019-06-19T15:23:13Z

These tracepoints make it easier to troubleshoot XDP mem id disconnect. The xdp:mem_disconnect tracepoint cannot be replaced via kprobe. It is placed at the last stable place for the pointer to struct xdp_mem_allocator, just before it's scheduled for RCU removal. It also extract info on 'safe_to_remove' and 'force'. Detailed info about in-flight pages is not available at this layer. The next patch will added tracepoints needed at the page_pool layer for this. Signed-off-by: Jesper Dangaard Brouer Signed-off-by: David S. Miller

bpf: fix redirect to map under tail calls

2018-08-17T22:56:23Z

Commits 109980b894e9 ("bpf: don't select potentially stale ri->map from buggy xdp progs") and 7c3001313396 ("bpf: fix ri->map_owner pointer on bpf_prog_realloc") tried to mitigate that buggy programs using bpf_redirect_map() helper call do not leave stale maps behind. Idea was to add a map_owner cookie into the per CPU struct redirect_info which was set to prog->aux by the prog making the helper call as a proof that the map is not stale since the prog is implicitly holding a reference to it. This owner cookie could later on get compared with the program calling into BPF whether they match and therefore the redirect could proceed with processing the map safely. In (obvious) hindsight, this approach breaks down when tail calls are involved since the original caller's prog->aux pointer does not have to match the one from one of the progs out of the tail call chain, and therefore the xdp buffer will be dropped instead of redirected. A way around that would be to fix the issue differently (which also allows to remove related work in fast path at the same time): once the life-time of a redirect map has come to its end we use it's map free callback where we need to wait on synchronize_rcu() for current outstanding xdp buffers and remove such a map pointer from the redirect info if found to be present. At that time no program is using this map anymore so we simply invalidate the map pointers to NULL iff they previously pointed to that instance while making sure that the redirect path only reads out the map once. Fixes: 97f91a7cf04f ("bpf: add bpf_redirect_map helper routine") Fixes: 109980b894e9 ("bpf: don't select potentially stale ri->map from buggy xdp progs") Reported-by: Sebastiano Miano Signed-off-by: Daniel Borkmann Acked-by: John Fastabend Signed-off-by: Alexei Starovoitov