From 96360004b8628541f5d05a845ea213267db0b1a2 Mon Sep 17 00:00:00 2001 From: Björn Töpel Date: Thu, 19 Dec 2019 07:10:03 +0100 Subject: xdp: Make devmap flush_list common for all map instances MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The devmap flush list is used to track entries that need to flushed from via the xdp_do_flush_map() function. This list used to be per-map, but there is really no reason for that. Instead make the flush list global for all devmaps, which simplifies __dev_map_flush() and dev_map_init_map(). Signed-off-by: Björn Töpel Signed-off-by: Alexei Starovoitov Acked-by: Toke Høiland-Jørgensen Link: https://lore.kernel.org/bpf/20191219061006.21980-6-bjorn.topel@gmail.com --- include/linux/bpf.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'include/linux') diff --git a/include/linux/bpf.h b/include/linux/bpf.h index d467983e61bb..31191804ca09 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -959,7 +959,7 @@ struct sk_buff; struct bpf_dtab_netdev *__dev_map_lookup_elem(struct bpf_map *map, u32 key); struct bpf_dtab_netdev *__dev_map_hash_lookup_elem(struct bpf_map *map, u32 key); -void __dev_map_flush(struct bpf_map *map); +void __dev_map_flush(void); int dev_map_enqueue(struct bpf_dtab_netdev *dst, struct xdp_buff *xdp, struct net_device *dev_rx); int dev_map_generic_redirect(struct bpf_dtab_netdev *dst, struct sk_buff *skb, @@ -1068,7 +1068,7 @@ static inline struct net_device *__dev_map_hash_lookup_elem(struct bpf_map *map return NULL; } -static inline void __dev_map_flush(struct bpf_map *map) +static inline void __dev_map_flush(void) { } -- cgit v1.3-14-g43fede From cdfafe98cabefeedbbc65af5c191c59745c03298 Mon Sep 17 00:00:00 2001 From: Björn Töpel Date: Thu, 19 Dec 2019 07:10:04 +0100 Subject: xdp: Make cpumap flush_list common for all map instances MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The cpumap flush list is used to track entries that need to flushed from via the xdp_do_flush_map() function. This list used to be per-map, but there is really no reason for that. Instead make the flush list global for all devmaps, which simplifies __cpu_map_flush() and cpu_map_alloc(). Signed-off-by: Björn Töpel Signed-off-by: Alexei Starovoitov Acked-by: Toke Høiland-Jørgensen Link: https://lore.kernel.org/bpf/20191219061006.21980-7-bjorn.topel@gmail.com --- include/linux/bpf.h | 4 ++-- kernel/bpf/cpumap.c | 36 ++++++++++++++++++------------------ net/core/filter.c | 2 +- 3 files changed, 21 insertions(+), 21 deletions(-) (limited to 'include/linux') diff --git a/include/linux/bpf.h b/include/linux/bpf.h index 31191804ca09..8f3e00c84f39 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -966,7 +966,7 @@ int dev_map_generic_redirect(struct bpf_dtab_netdev *dst, struct sk_buff *skb, struct bpf_prog *xdp_prog); struct bpf_cpu_map_entry *__cpu_map_lookup_elem(struct bpf_map *map, u32 key); -void __cpu_map_flush(struct bpf_map *map); +void __cpu_map_flush(void); int cpu_map_enqueue(struct bpf_cpu_map_entry *rcpu, struct xdp_buff *xdp, struct net_device *dev_rx); @@ -1097,7 +1097,7 @@ struct bpf_cpu_map_entry *__cpu_map_lookup_elem(struct bpf_map *map, u32 key) return NULL; } -static inline void __cpu_map_flush(struct bpf_map *map) +static inline void __cpu_map_flush(void) { } diff --git a/kernel/bpf/cpumap.c b/kernel/bpf/cpumap.c index f9deed659798..70f71b154fa5 100644 --- a/kernel/bpf/cpumap.c +++ b/kernel/bpf/cpumap.c @@ -72,17 +72,18 @@ struct bpf_cpu_map { struct bpf_map map; /* Below members specific for map type */ struct bpf_cpu_map_entry **cpu_map; - struct list_head __percpu *flush_list; }; +static DEFINE_PER_CPU(struct list_head, cpu_map_flush_list); + static int bq_flush_to_queue(struct xdp_bulk_queue *bq); static struct bpf_map *cpu_map_alloc(union bpf_attr *attr) { struct bpf_cpu_map *cmap; int err = -ENOMEM; - int ret, cpu; u64 cost; + int ret; if (!capable(CAP_SYS_ADMIN)) return ERR_PTR(-EPERM); @@ -106,7 +107,6 @@ static struct bpf_map *cpu_map_alloc(union bpf_attr *attr) /* make sure page count doesn't overflow */ cost = (u64) cmap->map.max_entries * sizeof(struct bpf_cpu_map_entry *); - cost += sizeof(struct list_head) * num_possible_cpus(); /* Notice returns -EPERM on if map size is larger than memlock limit */ ret = bpf_map_charge_init(&cmap->map.memory, cost); @@ -115,23 +115,14 @@ static struct bpf_map *cpu_map_alloc(union bpf_attr *attr) goto free_cmap; } - cmap->flush_list = alloc_percpu(struct list_head); - if (!cmap->flush_list) - goto free_charge; - - for_each_possible_cpu(cpu) - INIT_LIST_HEAD(per_cpu_ptr(cmap->flush_list, cpu)); - /* Alloc array for possible remote "destination" CPUs */ cmap->cpu_map = bpf_map_area_alloc(cmap->map.max_entries * sizeof(struct bpf_cpu_map_entry *), cmap->map.numa_node); if (!cmap->cpu_map) - goto free_percpu; + goto free_charge; return &cmap->map; -free_percpu: - free_percpu(cmap->flush_list); free_charge: bpf_map_charge_finish(&cmap->map.memory); free_cmap: @@ -526,7 +517,6 @@ static void cpu_map_free(struct bpf_map *map) /* bq flush and cleanup happens after RCU grace-period */ __cpu_map_entry_replace(cmap, i, NULL); /* call_rcu */ } - free_percpu(cmap->flush_list); bpf_map_area_free(cmap->cpu_map); kfree(cmap); } @@ -618,7 +608,7 @@ static int bq_flush_to_queue(struct xdp_bulk_queue *bq) */ static int bq_enqueue(struct bpf_cpu_map_entry *rcpu, struct xdp_frame *xdpf) { - struct list_head *flush_list = this_cpu_ptr(rcpu->cmap->flush_list); + struct list_head *flush_list = this_cpu_ptr(&cpu_map_flush_list); struct xdp_bulk_queue *bq = this_cpu_ptr(rcpu->bulkq); if (unlikely(bq->count == CPU_MAP_BULK_SIZE)) @@ -657,10 +647,9 @@ int cpu_map_enqueue(struct bpf_cpu_map_entry *rcpu, struct xdp_buff *xdp, return 0; } -void __cpu_map_flush(struct bpf_map *map) +void __cpu_map_flush(void) { - struct bpf_cpu_map *cmap = container_of(map, struct bpf_cpu_map, map); - struct list_head *flush_list = this_cpu_ptr(cmap->flush_list); + struct list_head *flush_list = this_cpu_ptr(&cpu_map_flush_list); struct xdp_bulk_queue *bq, *tmp; list_for_each_entry_safe(bq, tmp, flush_list, flush_node) { @@ -670,3 +659,14 @@ void __cpu_map_flush(struct bpf_map *map) wake_up_process(bq->obj->kthread); } } + +static int __init cpu_map_init(void) +{ + int cpu; + + for_each_possible_cpu(cpu) + INIT_LIST_HEAD(&per_cpu(cpu_map_flush_list, cpu)); + return 0; +} + +subsys_initcall(cpu_map_init); diff --git a/net/core/filter.c b/net/core/filter.c index b7570cb84902..c706325b3e66 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -3558,7 +3558,7 @@ void xdp_do_flush_map(void) __dev_map_flush(); break; case BPF_MAP_TYPE_CPUMAP: - __cpu_map_flush(map); + __cpu_map_flush(); break; case BPF_MAP_TYPE_XSKMAP: __xsk_map_flush(); -- cgit v1.3-14-g43fede From 332f22a60e4c3492d4953cd6f7aaa4e8bd0bba97 Mon Sep 17 00:00:00 2001 From: Björn Töpel Date: Thu, 19 Dec 2019 07:10:05 +0100 Subject: xdp: Remove map_to_flush and map swap detection MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Now that all XDP maps that can be used with bpf_redirect_map() tracks entries to be flushed in a global fashion, there is not need to track that the map has changed and flush from xdp_do_generic_map() anymore. All entries will be flushed in xdp_do_flush_map(). This means that the map_to_flush can be removed, and the corresponding checks. Moving the flush logic to one place, xdp_do_flush_map(), give a bulking behavior and performance boost. Signed-off-by: Björn Töpel Signed-off-by: Alexei Starovoitov Acked-by: Toke Høiland-Jørgensen Link: https://lore.kernel.org/bpf/20191219061006.21980-8-bjorn.topel@gmail.com --- include/linux/filter.h | 1 - net/core/filter.c | 27 +++------------------------ 2 files changed, 3 insertions(+), 25 deletions(-) (limited to 'include/linux') diff --git a/include/linux/filter.h b/include/linux/filter.h index 37ac7025031d..69d6706fc889 100644 --- a/include/linux/filter.h +++ b/include/linux/filter.h @@ -592,7 +592,6 @@ struct bpf_redirect_info { u32 tgt_index; void *tgt_value; struct bpf_map *map; - struct bpf_map *map_to_flush; u32 kern_flags; }; diff --git a/net/core/filter.c b/net/core/filter.c index c706325b3e66..d9caa3e57ea1 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -3547,26 +3547,9 @@ static int __bpf_tx_xdp_map(struct net_device *dev_rx, void *fwd, void xdp_do_flush_map(void) { - struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info); - struct bpf_map *map = ri->map_to_flush; - - ri->map_to_flush = NULL; - if (map) { - switch (map->map_type) { - case BPF_MAP_TYPE_DEVMAP: - case BPF_MAP_TYPE_DEVMAP_HASH: - __dev_map_flush(); - break; - case BPF_MAP_TYPE_CPUMAP: - __cpu_map_flush(); - break; - case BPF_MAP_TYPE_XSKMAP: - __xsk_map_flush(); - break; - default: - break; - } - } + __dev_map_flush(); + __cpu_map_flush(); + __xsk_map_flush(); } EXPORT_SYMBOL_GPL(xdp_do_flush_map); @@ -3615,14 +3598,10 @@ static int xdp_do_redirect_map(struct net_device *dev, struct xdp_buff *xdp, ri->tgt_value = NULL; WRITE_ONCE(ri->map, NULL); - if (ri->map_to_flush && unlikely(ri->map_to_flush != map)) - xdp_do_flush_map(); - err = __bpf_tx_xdp_map(dev, fwd, map, xdp); if (unlikely(err)) goto err; - ri->map_to_flush = map; _trace_xdp_redirect_map(dev, xdp_prog, fwd, map, index); return 0; err: -- cgit v1.3-14-g43fede