introduce support for XDP programs in CPUMAP
Subsystems (9)
v5 cover introduce support for XDP programs in CPUMAP
Similar to what David Ahern proposed in [1] for DEVMAPs, introduce the capability to attach and run a XDP program to CPUMAP entries.
The idea behind this feature is to add the possibility to define on which CPU run the eBPF program if the underlying hw does not support RSS.
I respin patch 1/6 from a previous series sent by David [2].
The functionality has been tested on Marvell Espressobin, i40e and mlx5. Detailed tests results can be found here:
https://github.com/xdp-project/xdp-project/blob/master/areas/cpumap/cpumap04-map-xdp-prog.org
Changes since v4:
- move xdp_clear_return_frame_no_direct inside rcu section
- update David Ahern's email address
Changes since v3:
- fix typo in commit message
- fix access to ctx->ingress_ifindex in cpumap bpf selftest
Changes since v2:
- improved comments
- fix return value in xdp_convert_buff_to_frame
- added patch 1/9: "cpumap: use non-locked version __ptr_ring_consume_batched"
- do not run kmem_cache_alloc_bulk if all frames have been consumed by the XDP program attached to the CPUMAP entry
- removed bpf_trace_printk in kselftest
Changes since v1:
- added performance test results
- added kselftest support
- fixed memory accounting with page_pool
- extended xdp_redirect_cpu_user.c to load an external program to perform redirect
- reported ifindex to attached eBPF program
- moved bpf_cpumap_val definition to include/uapi/linux/bpf.h
[1] https://patchwork.ozlabs.org/project/netdev/cover/[email protected]/
[2] https://patchwork.ozlabs.org/project/netdev/patch/[email protected]/
David Ahern (1):
net: refactor xdp_convert_buff_to_frame
Jesper Dangaard Brouer (1):
cpumap: use non-locked version __ptr_ring_consume_batched
Lorenzo Bianconi (7):
samples/bpf: xdp_redirect_cpu_user: do not update bpf maps in option
loop
cpumap: formalize map value as a named struct
bpf: cpumap: add the possibility to attach an eBPF program to cpumap
bpf: cpumap: implement XDP_REDIRECT for eBPF programs attached to map
entries
libbpf: add SEC name for xdp programs attached to CPUMAP samples/bpf: xdp_redirect_cpu: load a eBPF program on cpumap
selftest: add tests for XDP programs in CPUMAP entries
include/linux/bpf.h | 6 + include/net/xdp.h | 41 ++-- include/trace/events/xdp.h | 16 +- include/uapi/linux/bpf.h | 14 ++ kernel/bpf/cpumap.c | 161 +++++++++++--- net/core/dev.c | 9 + samples/bpf/xdp_redirect_cpu_kern.c | 25 ++- samples/bpf/xdp_redirect_cpu_user.c | 209 ++++++++++++++++-- tools/include/uapi/linux/bpf.h | 14 ++ tools/lib/bpf/libbpf.c | 2 + .../bpf/prog_tests/xdp_cpumap_attach.c | 70 ++++++ .../bpf/progs/test_xdp_with_cpumap_helpers.c | 36 +++ 12 files changed, 531 insertions(+), 72 deletions(-) create mode 100644 tools/testing/selftests/bpf/prog_tests/xdp_cpumap_attach.c create mode 100644 tools/testing/selftests/bpf/progs/test_xdp_with_cpumap_helpers.c
Signature · 1 line
2.26.2
PATCH v5 1/9 cpumap: use non-locked version __ptr_ring_consume_batched
From: Jesper Dangaard Brouer <[email protected]>
Commit 77361825bb01 ("bpf: cpumap use ptr_ring_consume_batched") changed away from using single frame ptr_ring dequeue (__ptr_ring_consume) to consume a batched, but it uses a locked version, which as the comment explain isn't needed.
Change to use the non-locked version __ptr_ring_consume_batched.
--- kernel/bpf/cpumap.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
kernel/bpf/cpumap.c +1 -1
@@ -259,7 +259,7 @@ static int cpu_map_kthread_run(void *data)* kthread CPU pinned. Lockless access to ptr_ring * consume side valid as no-resize allowed of queue. */ - n =ptr_ring_consume_batched (rcpu->queue, frames,CPUMAP_BATCH ); + n =__ptr_ring_consume_batched (rcpu->queue, frames,CPUMAP_BATCH );for (i =0 ; i < n; i++) {void *f = frames[i];
Signature · 1 line
2.26.2
PATCH v5 2/9 net: refactor xdp_convert_buff_to_frame
In reply to Lorenzo BianconiFrom: David Ahern <[email protected]>
Move the guts of xdp_convert_buff_to_frame to a new helper, xdp_update_frame_from_buff so it can be reused removing code duplication
--- include/net/xdp.h | 35 ++++++++++++++++++++++------------- 1 file changed, 22 insertions(+), 13 deletions(-)
include/net/xdp.h +22 -13
@@ -121,39 +121,48 @@ void xdp_convert_frame_to_buff(struct xdp_frame *frame, struct xdp_buff *xdp) xdp->frame_sz = frame->frame_sz; } -/* Convert xdp_buff to xdp_frame */ static inline -struct xdp_frame *xdp_convert_buff_to_frame (struct xdp_buff *xdp) +int xdp_update_frame_from_buff (struct xdp_buff *xdp, +struct xdp_frame *xdp_frame) { -struct xdp_frame *xdp_frame; -int metasize; -int headroom; - -if (xdp->rxq->mem.type ==MEM_TYPE_XSK_BUFF_POOL ) -return xdp_convert_zc_to_xdp_frame (xdp); +int metasize, headroom;/* Assure headroom is available for storing info */ headroom = xdp->data - xdp->data_hard_start; metasize = xdp->data - xdp->data_meta; metasize = metasize >0 ? metasize :0 ;if (unlikely ((headroom - metasize) <sizeof (*xdp_frame))) -return NULL ; +return -ENOSPC ;/* Catch if driver didn't reserve tailroom for skb_shared_info */ if (unlikely (xdp->data_end >xdp_data_hard_end (xdp))) {XDP_WARN ("Driver BUG: missing reserved tailroom" ); -return NULL ; +return -ENOSPC ; } -/* Store info in top of packet */ - xdp_frame = xdp->data_hard_start; - xdp_frame->data = xdp->data; xdp_frame->len = xdp->data_end - xdp->data; xdp_frame->headroom = headroom -sizeof (*xdp_frame); xdp_frame->metasize = metasize; xdp_frame->frame_sz = xdp->frame_sz; +return 0 ; +} + +/* Convert xdp_buff to xdp_frame */ +static inline +struct xdp_frame *xdp_convert_buff_to_frame (struct xdp_buff *xdp) +{ +struct xdp_frame *xdp_frame; + +if (xdp->rxq->mem.type ==MEM_TYPE_XSK_BUFF_POOL ) +return xdp_convert_zc_to_xdp_frame (xdp); + +/* Store info in top of packet */ + xdp_frame = xdp->data_hard_start; +if (unlikely (xdp_update_frame_from_buff (xdp, xdp_frame) <0 )) +return NULL ; +/* rxq only valid until napi_schedule ends, convert to xdp_mem_info */ xdp_frame->mem = xdp->rxq->mem;
Signature · 1 line
2.26.2
PATCH v5 3/9 samples/bpf: xdp_redirect_cpu_user: do not update bpf maps in option loop
In reply to Lorenzo BianconiDo not update xdp_redirect_cpu maps running while option loop but defer it after all available options have been parsed. This is a preliminary patch to pass the program name we want to attach to the map entries as a user option
--- samples/bpf/xdp_redirect_cpu_user.c | 36 +++++++++++++++++++++-------- 1 file changed, 27 insertions(+), 9 deletions(-)
samples/bpf/xdp_redirect_cpu_user.c +27 -9
@@ -681,6 +681,7 @@ int main(int argc, char **argv)int add_cpu =-1 ;int opt, err;int prog_fd; +int *cpu, i;__u32 qsize; n_cpus =get_nprocs_conf ();
@@ -716,6 +717,13 @@ int main(int argc, char **argv) }mark_cpus_unavailable (); + cpu =malloc (n_cpus *sizeof (int )); +if (!cpu) { +fprintf (stderr,"failed to allocate cpu array\n" ); +return EXIT_FAIL ; + } +memset (cpu,0 , n_cpus *sizeof (int )); +/* Parse commands line args */ while ((opt =getopt_long (argc, argv,"hSd:s:p:q:c:xzF" , long_options, &longindex)) !=-1 ) {
@@ -760,8 +768,7 @@ int main(int argc, char **argv) errno, strerror(errno)); goto error; } -create_cpu_entry (add_cpu, qsize, added_cpus, true); - added_cpus++; + cpu[added_cpus++] = add_cpu;break ;case 'q' : qsize =atoi (optarg);
@@ -772,6 +779,7 @@ int main(int argc, char **argv)case 'h' : error:default : +free (cpu);usage (argv, obj);return EXIT_FAIL_OPTION ; }
@@ -784,16 +792,21 @@ int main(int argc, char **argv)if (ifindex ==-1 ) {fprintf (stderr,"ERR: required option --dev missing\n" );usage (argv, obj); -return EXIT_FAIL_OPTION ; + err =EXIT_FAIL_OPTION ; + goto out; }/* Required option */ if (add_cpu ==-1 ) {fprintf (stderr,"ERR: required option --cpu missing\n" );fprintf (stderr," Specify multiple --cpu option to add more\n" );usage (argv, obj); -return EXIT_FAIL_OPTION ; + err =EXIT_FAIL_OPTION ; + goto out; } +for (i =0 ; i < added_cpus; i++) +create_cpu_entry (cpu[i], qsize, i, true); +/* Remove XDP program when program is interrupted or killed */ signal (SIGINT , int_exit);signal (SIGTERM , int_exit);
@@ -801,27 +814,32 @@ int main(int argc, char **argv) prog =bpf_object__find_program_by_title (obj, prog_name);if (!prog) {fprintf (stderr,"bpf_object__find_program_by_title failed\n" ); -return EXIT_FAIL ; + err =EXIT_FAIL ; + goto out; } prog_fd =bpf_program__fd (prog);if (prog_fd <0 ) {fprintf (stderr,"bpf_program__fd failed\n" ); -return EXIT_FAIL ; + err =EXIT_FAIL ; + goto out; }if (bpf_set_link_xdp_fd (ifindex, prog_fd, xdp_flags) <0 ) {fprintf (stderr,"link set xdp fd failed\n" ); -return EXIT_FAIL_XDP ; + err =EXIT_FAIL_XDP ; + goto out; } err =bpf_obj_get_info_by_fd (prog_fd, &info, &info_len);if (err) {printf ("can't get prog info - %s\n" ,strerror (errno)); -return err; + goto out; } prog_id = info.id;stats_poll (interval, use_separators, prog_name, stress_mode); -return EXIT_OK ; +out: +free (cpu); +return err; }
Signature · 1 line
2.26.2
PATCH v5 4/9 cpumap: formalize map value as a named struct
In reply to Lorenzo BianconiAs it has been already done for devmap, introduce 'struct bpf_cpumap_val' to formalize the expected values that can be passed in for a CPUMAP. Update cpumap code to use the struct.
--- include/uapi/linux/bpf.h | 9 +++++++++ kernel/bpf/cpumap.c | 25 +++++++++++++------------ tools/include/uapi/linux/bpf.h | 9 +++++++++ 3 files changed, 31 insertions(+), 12 deletions(-)
include/uapi/linux/bpf.h +9 -0
@@ -3812,6 +3812,15 @@ struct bpf_devmap_val { } bpf_prog; }; +/* CPUMAP map-value layout +* +* The struct data-layout of map-value is a configuration interface. +* New members can only be added to the end of this structure. +*/ +struct bpf_cpumap_val { +__u32 qsize;/* queue size to remote target CPU */ +}; +enum sk_action {SK_DROP =0 ,SK_PASS ,
kernel/bpf/cpumap.c +13 -12
@@ -52,7 +52,6 @@ struct xdp_bulk_queue {struct bpf_cpu_map_entry {u32 cpu;/* kthread CPU and map index */ int map_id;/* Back reference to map */ -u32 qsize;/* Queue size placeholder for map lookup */ /* XDP can run multiple RX-ring queues, need __percpu enqueue store */ struct xdp_bulk_queue __percpu *bulkq;
@@ -66,6 +65,8 @@ struct bpf_cpu_map_entry {atomic_t refcnt;/* Control when this struct can be free'ed */ struct rcu_head rcu; + +struct bpf_cpumap_val value; };struct bpf_cpu_map {
@@ -307,8 +308,8 @@ static int cpu_map_kthread_run(void *data)return 0 ; } -static struct bpf_cpu_map_entry *__cpu_map_entry_alloc (u32 qsize,u32 cpu, -int map_id) +static struct bpf_cpu_map_entry * +__cpu_map_entry_alloc (struct bpf_cpumap_val *value,u32 cpu,int map_id) {gfp_t gfp =GFP_KERNEL | __GFP_NOWARN;struct bpf_cpu_map_entry *rcpu;
@@ -338,13 +339,13 @@ static struct bpf_cpu_map_entry *__cpu_map_entry_alloc(u32 qsize, u32 cpu,if (!rcpu->queue) goto free_bulkq; - err =ptr_ring_init (rcpu->queue, qsize, gfp); + err =ptr_ring_init (rcpu->queue, value->qsize, gfp);if (err) goto free_queue; rcpu->cpu = cpu; rcpu->map_id = map_id; - rcpu->qsize = qsize; + rcpu->value.qsize = value->qsize;/* Setup kthread */ rcpu->kthread = kthread_create_on_node(cpu_map_kthread_run, rcpu, numa,
@@ -437,12 +438,12 @@ static int cpu_map_update_elem(struct bpf_map *map, void *key, void *value, u64 map_flags) { struct bpf_cpu_map *cmap = container_of(map, struct bpf_cpu_map, map); +struct bpf_cpumap_val cpumap_value = {};struct bpf_cpu_map_entry *rcpu; -/* Array index key correspond to CPU number */ u32 key_cpu = *(u32 *)key; -/* Value is the queue size */ -u32 qsize = *(u32 *)value; + +memcpy (&cpumap_value, value, map->value_size);if (unlikely (map_flags >BPF_EXIST ))return -EINVAL ;
@@ -450,18 +451,18 @@ static int cpu_map_update_elem(struct bpf_map *map, void *key, void *value,return -E2BIG ;if (unlikely (map_flags ==BPF_NOEXIST ))return -EEXIST ; -if (unlikely (qsize >16384 ))/* sanity limit on qsize */ +if (unlikely (cpumap_value.qsize >16384 ))/* sanity limit on qsize */ return -EOVERFLOW ;/* Make sure CPU is a valid possible cpu */ if (key_cpu >= nr_cpumask_bits || !cpu_possible (key_cpu))return -ENODEV ; -if (qsize ==0 ) { +if (cpumap_value.qsize ==0 ) { rcpu =NULL ;/* Same as deleting */ }else {/* Updating qsize cause re-allocation of bpf_cpu_map_entry */ - rcpu =__cpu_map_entry_alloc (qsize, key_cpu, map->id); + rcpu =__cpu_map_entry_alloc (&cpumap_value, key_cpu, map->id);if (!rcpu)return -ENOMEM ; rcpu->cmap = cmap;
@@ -523,7 +524,7 @@ static void *cpu_map_lookup_elem(struct bpf_map *map, void *key)struct bpf_cpu_map_entry *rcpu =__cpu_map_lookup_elem (map, *(u32 *)key); -return rcpu ? &rcpu->qsize :NULL ; +return rcpu ? &rcpu->value :NULL ; }static int cpu_map_get_next_key (struct bpf_map *map,void *key,void *next_key)
tools/include/uapi/linux/bpf.h +9 -0
@@ -3812,6 +3812,15 @@ struct bpf_devmap_val { } bpf_prog; }; +/* CPUMAP map-value layout +* +* The struct data-layout of map-value is a configuration interface. +* New members can only be added to the end of this structure. +*/ +struct bpf_cpumap_val { +__u32 qsize;/* queue size to remote target CPU */ +}; +enum sk_action {SK_DROP =0 ,SK_PASS ,
Signature · 1 line
2.26.2
PATCH v5 5/9 bpf: cpumap: add the possibility to attach an eBPF program to cpumap
In reply to Lorenzo BianconiIntroduce the capability to attach an eBPF program to cpumap entries. The idea behind this feature is to add the possibility to define on which CPU run the eBPF program if the underlying hw does not support RSS. Current supported verdicts are XDP_DROP and XDP_PASS.
This patch has been tested on Marvell ESPRESSObin using xdp_redirect_cpu sample available in the kernel tree to identify possible performance regressions. Results show there are no observable differences in packet-per-second:
$./xdp_redirect_cpu --progname xdp_cpu_map0 --dev eth0 --cpu 1
rx: 354.8 Kpps
rx: 356.0 Kpps
rx: 356.8 Kpps
rx: 356.3 Kpps
rx: 356.6 Kpps
rx: 356.6 Kpps
rx: 356.7 Kpps
rx: 355.8 Kpps
rx: 356.8 Kpps
rx: 356.8 Kpps
--- include/linux/bpf.h | 6 ++ include/net/xdp.h | 5 ++ include/trace/events/xdp.h | 14 ++-- include/uapi/linux/bpf.h | 5 ++ kernel/bpf/cpumap.c | 123 +++++++++++++++++++++++++++++---- net/core/dev.c | 9 +++ tools/include/uapi/linux/bpf.h | 5 ++ 7 files changed, 150 insertions(+), 17 deletions(-)
include/linux/bpf.h +6 -0
@@ -1272,6 +1272,7 @@ struct bpf_cpu_map_entry *__cpu_map_lookup_elem(struct bpf_map *map, u32 key);void __cpu_map_flush (void );int cpu_map_enqueue (struct bpf_cpu_map_entry *rcpu,struct xdp_buff *xdp,struct net_device *dev_rx); +bool cpu_map_prog_allowed (struct bpf_map *map);/* Return map's numa specified by userspace */ static inline int bpf_map_attr_numa_node (const union bpf_attr *attr)
@@ -1432,6 +1433,11 @@ static inline int cpu_map_enqueue(struct bpf_cpu_map_entry *rcpu,return 0 ; } +static inline bool cpu_map_prog_allowed (struct bpf_map *map) +{ +return false; +} +static inline struct bpf_prog *bpf_prog_get_type_path (const char *name,enum bpf_prog_type type) {
include/net/xdp.h +5 -0
@@ -98,6 +98,11 @@ struct xdp_frame {struct net_device *dev_rx;/* used by cpumap */ }; +struct xdp_cpumap_stats { +unsigned int pass; +unsigned int drop; +}; +/* Clear kernel pointers in xdp_frame */ static inline void xdp_scrub_frame (struct xdp_frame *frame) {
include/trace/events/xdp.h +10 -4
@@ -177,9 +177,9 @@ DEFINE_EVENT(xdp_redirect_template, xdp_redirect_map_err, TRACE_EVENT(xdp_cpumap_kthread, TP_PROTO(int map_id, unsigned int processed, unsigned int drops, - int sched), + int sched, struct xdp_cpumap_stats *xdp_stats), - TP_ARGS(map_id, processed, drops, sched), + TP_ARGS(map_id, processed, drops, sched, xdp_stats), TP_STRUCT__entry( __field(int, map_id)
@@ -188,6 +188,8 @@ TRACE_EVENT(xdp_cpumap_kthread, __field(unsigned int, drops) __field(unsigned int, processed) __field(int, sched) + __field(unsigned int, xdp_pass) + __field(unsigned int, xdp_drop) ), TP_fast_assign(
@@ -197,16 +199,20 @@ TRACE_EVENT(xdp_cpumap_kthread, __entry->drops = drops; __entry->processed = processed; __entry->sched = sched; + __entry->xdp_pass = xdp_stats->pass; + __entry->xdp_drop = xdp_stats->drop; ),TP_printk ("kthread" " cpu=%d map_id=%d action=%s" " processed=%u drops=%u" -" sched=%d" , +" sched=%d" +" xdp_pass=%u xdp_drop=%u" , __entry->cpu, __entry->map_id,__print_symbolic (__entry->act, __XDP_ACT_SYM_TAB), __entry->processed, __entry->drops, - __entry->sched) + __entry->sched, + __entry->xdp_pass, __entry->xdp_drop) ); TRACE_EVENT(xdp_cpumap_enqueue,
include/uapi/linux/bpf.h +5 -0
@@ -226,6 +226,7 @@ enum bpf_attach_type {BPF_CGROUP_INET4_GETSOCKNAME ,BPF_CGROUP_INET6_GETSOCKNAME ,BPF_XDP_DEVMAP , +BPF_XDP_CPUMAP , __MAX_BPF_ATTACH_TYPE };
@@ -3819,6 +3820,10 @@ struct bpf_devmap_val {*/ struct bpf_cpumap_val {__u32 qsize;/* queue size to remote target CPU */ +union { +int fd;/* prog fd on map write */ +__u32 id;/* prog id on map read */ + } bpf_prog; };enum sk_action {
kernel/bpf/cpumap.c +110 -13
201 lines not on this page · raw message
net/core/dev.c +9 -0
@@ -5440,6 +5440,8 @@ static int generic_xdp_install(struct net_device *dev, struct netdev_bpf *xdp)for (i =0 ; i < new->aux->used_map_cnt; i++) {if (dev_map_can_have_prog (new->aux->used_maps[i]))return -EINVAL ; +if (cpu_map_prog_allowed (new->aux->used_maps[i])) +return -EINVAL ; } }
@@ -8864,6 +8866,13 @@ int dev_change_xdp_fd(struct net_device *dev, struct netlink_ext_ack *extack,return -EINVAL ; } +if (prog->expected_attach_type ==BPF_XDP_CPUMAP ) { +NL_SET_ERR_MSG (extack, +"BPF_XDP_CPUMAP programs can not be attached to a device" ); +bpf_prog_put (prog); +return -EINVAL ; + } +/* prog->aux->id may be 0 for orphaned device-bound progs */ if (prog->aux->id && prog->aux->id == prog_id) {bpf_prog_put (prog);
tools/include/uapi/linux/bpf.h +5 -0
@@ -226,6 +226,7 @@ enum bpf_attach_type {BPF_CGROUP_INET4_GETSOCKNAME ,BPF_CGROUP_INET6_GETSOCKNAME ,BPF_XDP_DEVMAP , +BPF_XDP_CPUMAP , __MAX_BPF_ATTACH_TYPE };
@@ -3819,6 +3820,10 @@ struct bpf_devmap_val {*/ struct bpf_cpumap_val {__u32 qsize;/* queue size to remote target CPU */ +union { +int fd;/* prog fd on map write */ +__u32 id;/* prog id on map read */ + } bpf_prog; };enum sk_action {
Signature · 1 line
2.26.2
Daniel Borkmann
maintainerRe: [PATCH v5 bpf-next 5/9] bpf: cpumap: add the possibility to attach an eBPF program to cpumap
On 6/30/20 2:49 PM, Lorenzo Bianconi wrote:
[...]
Quoted 66 lines
include/uapi/linux/bpf.h +5
-0@@ -226,6 +226,7 @@ enum bpf_attach_type {BPF_CGROUP_INET4_GETSOCKNAME ,BPF_CGROUP_INET6_GETSOCKNAME ,BPF_XDP_DEVMAP , +BPF_XDP_CPUMAP , __MAX_BPF_ATTACH_TYPE };@@ -3819,6 +3820,10 @@ struct bpf_devmap_val {*/ struct bpf_cpumap_val {__u32 qsize;/* queue size to remote target CPU */ +union { +int fd;/* prog fd on map write */ +__u32 id;/* prog id on map read */ + } bpf_prog; };enum sk_action {kernel/bpf/cpumap.c +13
-1@@ -67,6 +67,7 @@ struct bpf_cpu_map_entry {struct rcu_head rcu;struct bpf_cpumap_val value; +struct bpf_prog *prog; };struct bpf_cpu_map {@@ -81,6 +82,7 @@ static int bq_flush_to_queue(struct xdp_bulk_queue *bq);static struct bpf_map *cpu_map_alloc (union bpf_attr *attr) { +u32 value_size = attr->value_size;struct bpf_cpu_map *cmap;int err = -ENOMEM ;u64 cost;@@ -91,7 +93,9 @@ static struct bpf_map *cpu_map_alloc(union bpf_attr *attr)/* check sanity of attributes */ if (attr->max_entries ==0 || attr->key_size !=4 || - attr->value_size !=4 || attr->map_flags & ~BPF_F_NUMA_NODE ) + (value_size != offsetofend(struct bpf_cpumap_val, qsize) && + value_size != offsetofend(struct bpf_cpumap_val, bpf_prog.fd)) || + attr->map_flags & ~BPF_F_NUMA_NODE )return ERR_PTR (-EINVAL ); cmap =kzalloc (sizeof (*cmap),GFP_USER );@@ -221,6 +225,64 @@ static void put_cpu_map_entry(struct bpf_cpu_map_entry *rcpu) } } +static int cpu_map_bpf_prog_run_xdp (struct bpf_cpu_map_entry *rcpu, +void **frames,int n, +struct xdp_cpumap_stats *stats) +{ +struct xdp_rxq_info rxq; +struct bpf_prog *prog; +struct xdp_buff xdp; +int i, nframes =0 ;
kernel/bpf/cpumap.c static void put_cpu_map_entry(struct bpf_cpu_map_entry *rcpu) · line 245
Quoted 10 lines
kernel/bpf/cpumap.c +10
-0+ +if (!rcpu->prog) +return n; + +rcu_read_lock (); + +xdp_set_return_frame_no_direct (); + xdp.rxq = &rxq; + + prog =READ_ONCE (rcpu->prog);
What purpose does the READ_ONCE() have here, also given you don't use it in above check? Since upon map update you realloc, repopulate and then xchg() the rcpu entry itself, there is never the case where you xchg() or WRITE_ONCE() the rcpu->prog, so what does READ_ONCE() serve in this context? Imho, it should probably just be deleted and plain rcpu->prog used to avoid confusion.
Quoted 39 lines
kernel/bpf/cpumap.c +39
-0+for (i =0 ; i < n; i++) { +struct xdp_frame *xdpf = frames[i]; +u32 act; +int err; + + rxq.dev = xdpf->dev_rx; + rxq.mem = xdpf->mem; +/* TODO: report queue_index to xdp_rxq_info */ + +xdp_convert_frame_to_buff (xdpf, &xdp); + + act =bpf_prog_run_xdp (prog, &xdp); +switch (act) { +case XDP_PASS : + err =xdp_update_frame_from_buff (&xdp, xdpf); +if (err <0 ) { +xdp_return_frame (xdpf); + stats->drop++; + }else { + frames[nframes++] = xdpf; + stats->pass++; + } +break ; +default : +bpf_warn_invalid_xdp_action (act); +/* fallthrough */ +case XDP_DROP : +xdp_return_frame (xdpf); + stats->drop++; +break ; + } + } + +xdp_clear_return_frame_no_direct (); + +rcu_read_unlock (); + +return nframes; +}
[...]
kernel/bpf/cpumap.c static int cpu_map_kthread_run(void *data) · line 388
Quoted 11 lines
kernel/bpf/cpumap.c +11
-0+bool cpu_map_prog_allowed (struct bpf_map *map) +{ +return map->map_type ==BPF_MAP_TYPE_CPUMAP && + map->value_size != offsetofend(struct bpf_cpumap_val, qsize); +} + +static int __cpu_map_load_bpf_program (struct bpf_cpu_map_entry *rcpu,int fd) +{ +struct bpf_prog *prog; + + prog =bpf_prog_get_type_dev (fd,BPF_PROG_TYPE_XDP , false);
Nit: why the _dev variant; just use bpf_prog_get_type()?
Quoted 14 lines
kernel/bpf/cpumap.c +14
-0+if (IS_ERR (prog)) +return PTR_ERR (prog); + +if (prog->expected_attach_type !=BPF_XDP_CPUMAP ) { +bpf_prog_put (prog); +return -EINVAL ; + } + + rcpu->value.bpf_prog.id = prog->aux->id; + rcpu->prog = prog; + +return 0 ; +} +
Re: [PATCH v5 bpf-next 5/9] bpf: cpumap: add the possibility to attach an eBPF program to cpumap
Quoted 2 lines · Lorenzo Bianconi
[...]
[...]
Quoted 7 lines
kernel/bpf/cpumap.c static void put_cpu_map_entry(struct bpf_cpu_map_entry *rcpu) · line 245
Quoted 1 line
kernel/bpf/cpumap.c +1
-0+ prog =READ_ONCE (rcpu->prog);What purpose does the
READ_ONCE()have here, also given you don't use it in above check? Since upon map update you realloc, repopulate and thenxchg()the rcpu entry itself, there is never the case where youxchg()orWRITE_ONCE()thercpu->prog, so what doesREAD_ONCE()serve in this context? Imho, it should probably just be deleted and plainrcpu->progused to avoid confusion.
Hi Daniel,
ack, I will fix it in v6
Quoted 41 lines
Quoted 40 lines
kernel/bpf/cpumap.c +39
-0+for (i =0 ; i < n; i++) { +struct xdp_frame *xdpf = frames[i]; +u32 act; +int err; + + rxq.dev = xdpf->dev_rx; + rxq.mem = xdpf->mem; +/* TODO: report queue_index to xdp_rxq_info */ + +xdp_convert_frame_to_buff (xdpf, &xdp); + + act =bpf_prog_run_xdp (prog, &xdp); +switch (act) { +case XDP_PASS : + err =xdp_update_frame_from_buff (&xdp, xdpf); +if (err <0 ) { +xdp_return_frame (xdpf); + stats->drop++; + }else { + frames[nframes++] = xdpf; + stats->pass++; + } +break ; +default : +bpf_warn_invalid_xdp_action (act); +/* fallthrough */ +case XDP_DROP : +xdp_return_frame (xdpf); + stats->drop++; +break ; + } + } + +xdp_clear_return_frame_no_direct (); + +rcu_read_unlock (); + +return nframes; +}[...]
Quoted 13 lines
kernel/bpf/cpumap.c static int cpu_map_kthread_run(void *data) · line 388
Quoted 11 lines
kernel/bpf/cpumap.c +11
-0+bool cpu_map_prog_allowed (struct bpf_map *map) +{ +return map->map_type ==BPF_MAP_TYPE_CPUMAP && + map->value_size != offsetofend(struct bpf_cpumap_val, qsize); +} + +static int __cpu_map_load_bpf_program (struct bpf_cpu_map_entry *rcpu,int fd) +{ +struct bpf_prog *prog; + + prog =bpf_prog_get_type_dev (fd,BPF_PROG_TYPE_XDP , false);Nit: why the
_devvariant; just usebpf_prog_get_type()?
ack, I will fix in v6
Regards,
Lorenzo
Quoted 15 lines
Quoted 15 lines
kernel/bpf/cpumap.c +14
-0+if (IS_ERR (prog)) +return PTR_ERR (prog); + +if (prog->expected_attach_type !=BPF_XDP_CPUMAP ) { +bpf_prog_put (prog); +return -EINVAL ; + } + + rcpu->value.bpf_prog.id = prog->aux->id; + rcpu->prog = prog; + +return 0 ; +} +
Daniel Borkmann
maintainerRe: [PATCH v5 bpf-next 5/9] bpf: cpumap: add the possibility to attach an eBPF program to cpumap
In reply to Lorenzo BianconiOn 6/30/20 2:49 PM, Lorenzo Bianconi wrote:
[...]
Quoted 125 lines
kernel/bpf/cpumap.c +74
-11+static int cpu_map_bpf_prog_run_xdp (struct bpf_cpu_map_entry *rcpu, +void **frames,int n, +struct xdp_cpumap_stats *stats) +{ +struct xdp_rxq_info rxq; +struct bpf_prog *prog; +struct xdp_buff xdp; +int i, nframes =0 ; + +if (!rcpu->prog) +return n; + +rcu_read_lock (); + +xdp_set_return_frame_no_direct (); + xdp.rxq = &rxq; + + prog =READ_ONCE (rcpu->prog); +for (i =0 ; i < n; i++) { +struct xdp_frame *xdpf = frames[i]; +u32 act; +int err; + + rxq.dev = xdpf->dev_rx; + rxq.mem = xdpf->mem; +/* TODO: report queue_index to xdp_rxq_info */ + +xdp_convert_frame_to_buff (xdpf, &xdp); + + act =bpf_prog_run_xdp (prog, &xdp); +switch (act) { +case XDP_PASS : + err =xdp_update_frame_from_buff (&xdp, xdpf); +if (err <0 ) { +xdp_return_frame (xdpf); + stats->drop++; + }else { + frames[nframes++] = xdpf; + stats->pass++; + } +break ; +default : +bpf_warn_invalid_xdp_action (act); +/* fallthrough */ +case XDP_DROP : +xdp_return_frame (xdpf); + stats->drop++; +break ; + } + } + +xdp_clear_return_frame_no_direct (); + +rcu_read_unlock (); + +return nframes; +} +#define CPUMAP_BATCH 8static int cpu_map_kthread_run (void *data)@@ -235,11 +297,12 @@ static int cpu_map_kthread_run(void *data)* kthread_stop signal until queue is empty. */ while (!kthread_should_stop () || !__ptr_ring_empty (rcpu->queue)) { +struct xdp_cpumap_stats stats = {};/* zero stats */ +gfp_t gfp = __GFP_ZERO |GFP_ATOMIC ;unsigned int drops =0 , sched =0 ;void *frames[CPUMAP_BATCH ];void *skbs[CPUMAP_BATCH ]; -gfp_t gfp = __GFP_ZERO |GFP_ATOMIC ; -int i, n, m; +int i, n, m, nframes;/* Release CPU reschedule checks */ if (__ptr_ring_empty (rcpu->queue)) {@@ -260,8 +323,8 @@ static int cpu_map_kthread_run(void *data)* kthread CPU pinned. Lockless access to ptr_ring * consume side valid as no-resize allowed of queue. */ - n =__ptr_ring_consume_batched (rcpu->queue, frames,CPUMAP_BATCH ); - + n =__ptr_ring_consume_batched (rcpu->queue, frames, +CPUMAP_BATCH );for (i =0 ; i < n; i++) {void *f = frames[i];struct page *page =virt_to_page (f);@@ -273,15 +336,19 @@ static int cpu_map_kthread_run(void *data)prefetchw (page); } - m =kmem_cache_alloc_bulk (skbuff_head_cache, gfp, n, skbs); -if (unlikely (m ==0 )) { -for (i =0 ; i < n; i++) - skbs[i] =NULL ;/* effect: xdp_return_frame */ - drops = n; +/* Support running another XDP prog on this CPU */ + nframes =cpu_map_bpf_prog_run_xdp (rcpu, frames, n, &stats); +if (nframes) { + m =kmem_cache_alloc_bulk (skbuff_head_cache, gfp, nframes, skbs); +if (unlikely (m ==0 )) { +for (i =0 ; i < nframes; i++) + skbs[i] =NULL ;/* effect: xdp_return_frame */ + drops += nframes; + } }local_bh_disable (); -for (i =0 ; i < n; i++) { +for (i =0 ; i < nframes; i++) {struct xdp_frame *xdpf = frames[i];struct sk_buff *skb = skbs[i];int ret;@@ -298,7 +365,7 @@ static int cpu_map_kthread_run(void *data) drops++; }/* Feedback loop via tracepoint */ -trace_xdp_cpumap_kthread (rcpu->map_id, n, drops, sched); +trace_xdp_cpumap_kthread (rcpu->map_id, n, drops, sched, &stats);local_bh_enable ();/* resched point, may call do_softirq() */ }@@ -308,13 +375,38 @@ static int cpu_map_kthread_run(void *data)return 0 ; }
[...]
kernel/bpf/cpumap.c static void __cpu_map_entry_replace(struct bpf_cpu_map *cmap, · line 517
Quoted 9 lines
kernel/bpf/cpumap.c +2
-0@@ -415,6 +510,8 @@ static void __cpu_map_entry_replace(struct bpf_cpu_map *cmap, old_rcpu =xchg (&cmap->cpu_map[key_cpu], rcpu);if (old_rcpu) { +if (old_rcpu->prog) +bpf_prog_put (old_rcpu->prog);call_rcu (&old_rcpu->rcu, __cpu_map_entry_free);INIT_WORK (&old_rcpu->kthread_stop_wq, cpu_map_kthread_stop);schedule_work (&old_rcpu->kthread_stop_wq);
Hm, not quite sure I follow the logic here. Why is the bpf_prog_put() not placed inside __cpu_map_entry_free(), for example? Wouldn't this at least leave a potential small race window of UAF given the rest is still live? If we already piggy-back from RCU side on rcpu entry, why not having it in __cpu_map_entry_free()?
Thanks,
Daniel
Re: [PATCH v5 bpf-next 5/9] bpf: cpumap: add the possibility to attach an eBPF program to cpumap
Quoted 2 lines · Lorenzo Bianconi
[...]
[...]
Quoted 4 lines
Quoted 4 lines
old_rcpu = xchg(&cmap->cpu_map[key_cpu], rcpu); if (old_rcpu) {kernel/bpf/cpumap.c +2
-0+if (old_rcpu->prog) +bpf_prog_put (old_rcpu->prog);
Quoted 8 lines
Quoted 3 lines
call_rcu(&old_rcpu->rcu, __cpu_map_entry_free); INIT_WORK(&old_rcpu->kthread_stop_wq, cpu_map_kthread_stop); schedule_work(&old_rcpu->kthread_stop_wq);Hm, not quite sure I follow the logic here. Why is the
bpf_prog_put()not placed inside__cpu_map_entry_free(), for example? Wouldn't this at least leave a potential small race window of UAF given the rest is still live? If we already piggy-back from RCU side on rcpu entry, why not having it in__cpu_map_entry_free()?
ack right, thanks for spotting this issue. I guess we can even move "bpf_prog_put(rcpu->prog)" in put_cpu_map_entry() so the last consumer of bpf_cpu_map_entry will free the attached program. Agree?
Regards,
Lorenzo
Quoted 3 lines
Thanks,
Daniel
Daniel Borkmann
maintainerRe: [PATCH v5 bpf-next 5/9] bpf: cpumap: add the possibility to attach an eBPF program to cpumap
Quoted 18 lines · Lorenzo Bianconi
Quoted 2 lines · Lorenzo Bianconi
[...]
[...]
Quoted 4 lines
Quoted 4 lines
old_rcpu = xchg(&cmap->cpu_map[key_cpu], rcpu); if (old_rcpu) {kernel/bpf/cpumap.c +2
-0+if (old_rcpu->prog) +bpf_prog_put (old_rcpu->prog);Quoted 8 lines
Quoted 3 lines
call_rcu(&old_rcpu->rcu, __cpu_map_entry_free); INIT_WORK(&old_rcpu->kthread_stop_wq, cpu_map_kthread_stop); schedule_work(&old_rcpu->kthread_stop_wq);Hm, not quite sure I follow the logic here. Why is the
bpf_prog_put()not placed inside__cpu_map_entry_free(), for example? Wouldn't this at least leave a potential small race window of UAF given the rest is still live? If we already piggy-back from RCU side on rcpu entry, why not having it in__cpu_map_entry_free()?
Quoted 3 lines
ack right, thanks for spotting this issue. I guess we can even move "
bpf_prog_put(rcpu->prog)" input_cpu_map_entry()so the last consumer ofbpf_cpu_map_entrywill free the attached program. Agree?
Yes, that sounds reasonable to me.
Thanks,
Daniel
PATCH v5 6/9 bpf: cpumap: implement XDP_REDIRECT for eBPF programs attached to map entries
In reply to Lorenzo BianconiIntroduce XDP_REDIRECT support for eBPF programs attached to cpumap entries.
This patch has been tested on Marvell ESPRESSObin using a modified version of xdp_redirect_cpu sample in order to attach a XDP program to CPUMAP entries to perform a redirect on the mvneta interface. In particular the following scenario has been tested:
rq (cpu0) --> mvneta - XDP_REDIRECT (cpu0) --> CPUMAP - XDP_REDIRECT (cpu1) --> mvneta
$./xdp_redirect_cpu -p xdp_cpu_map0 -d eth0 -c 1 -e xdp_redirect \
-f xdp_redirect_kern.o -m tx_port -r eth0
tx: 285.2 Kpps rx: 285.2 Kpps
Attaching a simple XDP program on eth0 to perform XDP_TX gives comparable results:
tx: 288.4 Kpps rx: 288.4 Kpps
--- include/net/xdp.h | 1 + include/trace/events/xdp.h | 6 ++++-- kernel/bpf/cpumap.c | 17 +++++++++++++++-- 3 files changed, 20 insertions(+), 4 deletions(-)
include/net/xdp.h +1 -0
@@ -99,6 +99,7 @@ struct xdp_frame { };struct xdp_cpumap_stats { +unsigned int redirect;unsigned int pass;unsigned int drop; };
include/trace/events/xdp.h +4 -2
@@ -190,6 +190,7 @@ TRACE_EVENT(xdp_cpumap_kthread, __field(int, sched) __field(unsigned int, xdp_pass) __field(unsigned int, xdp_drop) + __field(unsigned int, xdp_redirect) ), TP_fast_assign(
@@ -201,18 +202,19 @@ TRACE_EVENT(xdp_cpumap_kthread, __entry->sched = sched; __entry->xdp_pass = xdp_stats->pass; __entry->xdp_drop = xdp_stats->drop; + __entry->xdp_redirect = xdp_stats->redirect; ),TP_printk ("kthread" " cpu=%d map_id=%d action=%s" " processed=%u drops=%u" " sched=%d" -" xdp_pass=%u xdp_drop=%u" , +" xdp_pass=%u xdp_drop=%u xdp_redirect=%u" , __entry->cpu, __entry->map_id,__print_symbolic (__entry->act, __XDP_ACT_SYM_TAB), __entry->processed, __entry->drops, __entry->sched, - __entry->xdp_pass, __entry->xdp_drop) + __entry->xdp_pass, __entry->xdp_drop, __entry->xdp_redirect) ); TRACE_EVENT(xdp_cpumap_enqueue,
kernel/bpf/cpumap.c +15 -2
@@ -237,7 +237,7 @@ static int cpu_map_bpf_prog_run_xdp(struct bpf_cpu_map_entry *rcpu,if (!rcpu->prog)return n; -rcu_read_lock (); +rcu_read_lock_bh ();xdp_set_return_frame_no_direct (); xdp.rxq = &rxq;
@@ -266,6 +266,16 @@ static int cpu_map_bpf_prog_run_xdp(struct bpf_cpu_map_entry *rcpu, stats->pass++; }break ; +case XDP_REDIRECT : + err =xdp_do_redirect (xdpf->dev_rx, &xdp, + prog); +if (unlikely (err)) { +xdp_return_frame (xdpf); + stats->drop++; + }else { + stats->redirect++; + } +break ;default :bpf_warn_invalid_xdp_action (act);/* fallthrough */
@@ -276,9 +286,12 @@ static int cpu_map_bpf_prog_run_xdp(struct bpf_cpu_map_entry *rcpu, } } +if (stats->redirect) +xdp_do_flush_map (); +xdp_clear_return_frame_no_direct (); -rcu_read_unlock (); +rcu_read_unlock_bh ();/* resched point, may call do_softirq() */ return nframes; }
Signature · 1 line
2.26.2
PATCH v5 7/9 libbpf: add SEC name for xdp programs attached to CPUMAP
In reply to Lorenzo BianconiAs for DEVMAP, support SEC("xdp_cpumap/") as a short cut for loading the program with type BPF_PROG_TYPE_XDP and expected attach type BPF_XDP_CPUMAP.
--- tools/lib/bpf/libbpf.c | 2 ++ 1 file changed, 2 insertions(+)
tools/lib/bpf/libbpf.c +2 -0
@@ -6906,6 +6906,8 @@ static const struct bpf_sec_def section_defs[] = { .attach_fn = attach_iter),BPF_EAPROG_SEC ("xdp_devmap" ,BPF_PROG_TYPE_XDP ,BPF_XDP_DEVMAP ), +BPF_EAPROG_SEC ("xdp_cpumap/" ,BPF_PROG_TYPE_XDP , +BPF_XDP_CPUMAP ),BPF_PROG_SEC ("xdp" ,BPF_PROG_TYPE_XDP ),BPF_PROG_SEC ("perf_event" ,BPF_PROG_TYPE_PERF_EVENT ), BPF_PROG_SEC("lwt_in", BPF_PROG_TYPE_LWT_IN),
Signature · 1 line
2.26.2
PATCH v5 8/9 samples/bpf: xdp_redirect_cpu: load a eBPF program on cpumap
In reply to Lorenzo BianconiExtend xdp_redirect_cpu_{usr,kern}.c adding the possibility to load a XDP program on cpumap entries. The following options have been added:
- mprog-name: cpumap entry program name
- mprog-filename: cpumap entry program filename
- redirect-device: output interface if the cpumap program performs a XDP_REDIRECT to an egress interface
- redirect-map: bpf map used to perform XDP_REDIRECT to an egress interface
- mprog-disable: disable loading XDP program on cpumap entries
Add xdp_pass, xdp_drop, xdp_redirect stats accounting
--- samples/bpf/xdp_redirect_cpu_kern.c | 25 ++-- samples/bpf/xdp_redirect_cpu_user.c | 175 +++++++++++++++++++++++++--- 2 files changed, 178 insertions(+), 22 deletions(-)
samples/bpf/xdp_redirect_cpu_kern.c +17 -8
@@ -21,7 +21,7 @@struct { __uint(type, BPF_MAP_TYPE_CPUMAP); __uint(key_size, sizeof(u32)); - __uint(value_size, sizeof(u32)); + __uint(value_size, sizeof(struct bpf_cpumap_val)); __uint(max_entries, MAX_CPUS); } cpu_map SEC(".maps");
@@ -30,6 +30,9 @@ struct datarec {__u64 processed;__u64 dropped;__u64 issue; +__u64 xdp_pass; +__u64 xdp_drop; +__u64 xdp_redirect; };/* Count RX packets, as XDP bpf_prog doesn't get direct TX-success
@@ -692,13 +695,16 @@ int trace_xdp_cpumap_enqueue(struct cpumap_enqueue_ctx *ctx)* Code in: kernel/include/trace/events/xdp.h */ struct cpumap_kthread_ctx { -u64 __pad;// First 8 bytes are not accessible by bpf code -int map_id;// offset:8; size:4; signed:1; -u32 act;// offset:12; size:4; signed:0; -int cpu;// offset:16; size:4; signed:1; -unsigned int drops;// offset:20; size:4; signed:0; -unsigned int processed;// offset:24; size:4; signed:0; -int sched;// offset:28; size:4; signed:1; +u64 __pad;// First 8 bytes are not accessible +int map_id;// offset:8; size:4; signed:1; +u32 act;// offset:12; size:4; signed:0; +int cpu;// offset:16; size:4; signed:1; +unsigned int drops;// offset:20; size:4; signed:0; +unsigned int processed;// offset:24; size:4; signed:0; +int sched;// offset:28; size:4; signed:1; +unsigned int xdp_pass;// offset:32; size:4; signed:0; +unsigned int xdp_drop;// offset:36; size:4; signed:0; +unsigned int xdp_redirect;// offset:40; size:4; signed:0; };SEC ("tracepoint/xdp/xdp_cpumap_kthread" )
@@ -712,6 +718,9 @@ int trace_xdp_cpumap_kthread(struct cpumap_kthread_ctx *ctx)return 0 ; rec->processed += ctx->processed; rec->dropped += ctx->drops; + rec->xdp_pass += ctx->xdp_pass; + rec->xdp_drop += ctx->xdp_drop; + rec->xdp_redirect += ctx->xdp_redirect;/* Count times kthread yielded CPU via schedule call */ if (ctx->sched)
samples/bpf/xdp_redirect_cpu_user.c +161 -14
310 lines not on this page · raw message
Signature · 1 line
2.26.2
PATCH v5 9/9 selftest: add tests for XDP programs in CPUMAP entries
In reply to Lorenzo BianconiSimilar to what have been done for DEVMAP, introduce tests to verify ability to add a XDP program to an entry in a CPUMAP. Verify CPUMAP programs can not be attached to devices as a normal XDP program, and only programs with BPF_XDP_CPUMAP attach type can be loaded in a CPUMAP.
--- .../bpf/prog_tests/xdp_cpumap_attach.c | 70 +++++++++++++++++++ .../bpf/progs/test_xdp_with_cpumap_helpers.c | 36 ++++++++++ 2 files changed, 106 insertions(+) create mode 100644 tools/testing/selftests/bpf/prog_tests/xdp_cpumap_attach.c create mode 100644 tools/testing/selftests/bpf/progs/test_xdp_with_cpumap_helpers.c
tools/testing/selftests/bpf/prog_tests/xdp_cpumap_attach.c new file +70 -0
@@ -0,0 +1,70 @@ +// SPDX-License-Identifier: GPL-2.0 +#include <uapi/linux/bpf.h> +#include <linux/if_link.h> +#include <test_progs.h> + +#include "test_xdp_with_cpumap_helpers.skel.h" + +#define IFINDEX_LO 1 + +void test_xdp_with_cpumap_helpers (void ) +{ +struct test_xdp_with_cpumap_helpers *skel; +struct bpf_prog_info info = {}; +struct bpf_cpumap_val val = { + .qsize =192 , + }; +__u32 duration =0 , idx =0 ; +__u32 len =sizeof (info); +int err, prog_fd, map_fd; + + skel =test_xdp_with_cpumap_helpers__open_and_load (); +if (CHECK_FAIL (!skel)) { +perror ("test_xdp_with_cpumap_helpers__open_and_load" ); +return ; + } + +/* can not attach program with cpumaps that allow programs +* as xdp generic +*/ + prog_fd =bpf_program__fd (skel->progs.xdp_redir_prog); + err =bpf_set_link_xdp_fd (IFINDEX_LO , prog_fd,XDP_FLAGS_SKB_MODE ); +CHECK (err ==0 ,"Generic attach of program with 8-byte CPUMAP" , +"should have failed\n" ); + + prog_fd =bpf_program__fd (skel->progs.xdp_dummy_cm); + map_fd =bpf_map__fd (skel->maps.cpu_map); + err =bpf_obj_get_info_by_fd (prog_fd, &info, &len); +if (CHECK_FAIL (err)) + goto out_close; + + val.bpf_prog.fd = prog_fd; + err =bpf_map_update_elem (map_fd, &idx, &val,0 ); +CHECK (err,"Add program to cpumap entry" ,"err %d errno %d\n" , + err, errno); + + err =bpf_map_lookup_elem (map_fd, &idx, &val); +CHECK (err,"Read cpumap entry" ,"err %d errno %d\n" , err, errno); +CHECK (info.id != val.bpf_prog.id,"Expected program id in cpumap entry" , +"expected %u read %u\n" , info.id, val.bpf_prog.id); + +/* can not attach BPF_XDP_CPUMAP program to a device */ + err =bpf_set_link_xdp_fd (IFINDEX_LO , prog_fd,XDP_FLAGS_SKB_MODE ); +CHECK (err ==0 ,"Attach of BPF_XDP_CPUMAP program" , +"should have failed\n" ); + + val.qsize =192 ; + val.bpf_prog.fd =bpf_program__fd (skel->progs.xdp_dummy_prog); + err =bpf_map_update_elem (map_fd, &idx, &val,0 ); +CHECK (err ==0 ,"Add non-BPF_XDP_CPUMAP program to cpumap entry" , +"should have failed\n" ); + +out_close: +test_xdp_with_cpumap_helpers__destroy (skel); +} + +void test_xdp_cpumap_attach (void ) +{ +if (test__start_subtest ("cpumap_with_progs" )) +test_xdp_with_cpumap_helpers (); +}
tools/testing/selftests/bpf/progs/test_xdp_with_cpumap_helpers.c new file +36 -0
@@ -0,0 +1,36 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include <linux/bpf.h> +#include <bpf/bpf_helpers.h> + +#define IFINDEX_LO 1 + +struct { + __uint(type, BPF_MAP_TYPE_CPUMAP); + __uint(key_size, sizeof(__u32)); + __uint(value_size, sizeof(struct bpf_cpumap_val)); + __uint(max_entries, 4); +} cpu_map SEC(".maps"); + +SEC("xdp_redir") +int xdp_redir_prog (struct xdp_md *ctx) +{ +return bpf_redirect_map (&cpu_map,1 ,0 ); +} + +SEC("xdp_dummy") +int xdp_dummy_prog (struct xdp_md *ctx) +{ +return XDP_PASS ; +} + +SEC("xdp_cpumap/dummy_cm") +int xdp_dummy_cm (struct xdp_md *ctx) +{ +if (ctx->ingress_ifindex ==IFINDEX_LO ) +return XDP_DROP ; + +return XDP_PASS ; +} + +char _license[] SEC("license") = "GPL";
Signature · 1 line
2.26.2