diff mbox series

[bpf-next,1/2] bpf, xdp: per-map bpf_redirect_map functions for XDP

Message ID 20210219145922.63655-2-bjorn.topel@gmail.com (mailing list archive)
State Superseded
Delegated to: BPF
Headers show
Series Optimize bpf_redirect_map()/xdp_do_redirect() | expand

Checks

Context Check Description
netdev/cover_letter success Link
netdev/fixes_present success Link
netdev/patch_count success Link
netdev/tree_selection success Clearly marked for bpf-next
netdev/subject_prefix success Link
netdev/cc_maintainers warning 7 maintainers not CCed: jonathan.lemon@gmail.com andrii@kernel.org yhs@fb.com bjorn@kernel.org kpsingh@kernel.org songliubraving@fb.com kafai@fb.com
netdev/source_inline success Was 1 now: 0
netdev/verify_signedoff success Link
netdev/module_param success Was 0 now: 0
netdev/build_32bit fail Errors and warnings before: 12076 this patch: 12077
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/verify_fixes success Link
netdev/checkpatch warning WARNING: line length of 81 exceeds 80 columns WARNING: line length of 82 exceeds 80 columns WARNING: line length of 84 exceeds 80 columns WARNING: line length of 87 exceeds 80 columns WARNING: line length of 88 exceeds 80 columns WARNING: line length of 89 exceeds 80 columns WARNING: line length of 91 exceeds 80 columns WARNING: line length of 94 exceeds 80 columns WARNING: line length of 95 exceeds 80 columns
netdev/build_allmodconfig_warn fail Errors and warnings before: 12718 this patch: 12719
netdev/header_inline success Link
netdev/stable success Stable not CCed

Commit Message

Björn Töpel Feb. 19, 2021, 2:59 p.m. UTC 
From: Björn Töpel <bjorn.topel@intel.com>

Currently the bpf_redirect_map() implementation dispatches to the
correct map-lookup function via a switch-statement. To avoid the
dispatching, this change adds one bpf_redirect_map() implementation per
map. Correct function is automatically selected by the BPF verifier.

rfc->v1: Get rid of the macro and use __always_inline. (Jesper)

Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
---
 include/linux/bpf.h    | 20 +++++++------
 include/linux/filter.h |  2 ++
 include/net/xdp_sock.h |  6 ++--
 kernel/bpf/cpumap.c    |  2 +-
 kernel/bpf/devmap.c    |  4 +--
 kernel/bpf/verifier.c  | 28 +++++++++++-------
 net/core/filter.c      | 67 ++++++++++++++++++++++++++----------------
 7 files changed, 76 insertions(+), 53 deletions(-)

Comments

Toke Høiland-Jørgensen Feb. 19, 2021, 5:05 p.m. UTC | #1 
Björn Töpel <bjorn.topel@gmail.com> writes:

> From: Björn Töpel <bjorn.topel@intel.com>
>
> Currently the bpf_redirect_map() implementation dispatches to the
> correct map-lookup function via a switch-statement. To avoid the
> dispatching, this change adds one bpf_redirect_map() implementation per
> map. Correct function is automatically selected by the BPF verifier.
>
> rfc->v1: Get rid of the macro and use __always_inline. (Jesper)
>
> Signed-off-by: Björn Töpel <bjorn.topel@intel.com>

Nice! Way better with the __always_inline. One small nit below, but
otherwise:

Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>

> ---
>  include/linux/bpf.h    | 20 +++++++------
>  include/linux/filter.h |  2 ++
>  include/net/xdp_sock.h |  6 ++--
>  kernel/bpf/cpumap.c    |  2 +-
>  kernel/bpf/devmap.c    |  4 +--
>  kernel/bpf/verifier.c  | 28 +++++++++++-------
>  net/core/filter.c      | 67 ++++++++++++++++++++++++++----------------
>  7 files changed, 76 insertions(+), 53 deletions(-)
>
> diff --git a/include/linux/bpf.h b/include/linux/bpf.h
> index cccaef1088ea..3dd186eeaf98 100644
> --- a/include/linux/bpf.h
> +++ b/include/linux/bpf.h
> @@ -314,12 +314,14 @@ enum bpf_return_type {
>  	RET_PTR_TO_BTF_ID,		/* returns a pointer to a btf_id */
>  };
>  
> +typedef u64 (*bpf_func_proto_func)(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5);
> +
>  /* eBPF function prototype used by verifier to allow BPF_CALLs from eBPF programs
>   * to in-kernel helper functions and for adjusting imm32 field in BPF_CALL
>   * instructions after verifying
>   */
>  struct bpf_func_proto {
> -	u64 (*func)(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5);
> +	bpf_func_proto_func func;
>  	bool gpl_only;
>  	bool pkt_access;
>  	enum bpf_return_type ret_type;
> @@ -1429,9 +1431,11 @@ struct btf *bpf_get_btf_vmlinux(void);
>  /* Map specifics */
>  struct xdp_buff;
>  struct sk_buff;
> +struct bpf_dtab_netdev;
> +struct bpf_cpu_map_entry;
>  
> -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_lookup_elem(struct bpf_map *map, u32 key);
> +void *__dev_map_hash_lookup_elem(struct bpf_map *map, u32 key);
>  void __dev_flush(void);
>  int dev_xdp_enqueue(struct net_device *dev, struct xdp_buff *xdp,
>  		    struct net_device *dev_rx);
> @@ -1441,7 +1445,7 @@ int dev_map_generic_redirect(struct bpf_dtab_netdev *dst, struct sk_buff *skb,
>  			     struct bpf_prog *xdp_prog);
>  bool dev_map_can_have_prog(struct bpf_map *map);
>  
> -struct bpf_cpu_map_entry *__cpu_map_lookup_elem(struct bpf_map *map, u32 key);
> +void *__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);
> @@ -1568,14 +1572,12 @@ static inline int bpf_obj_get_user(const char __user *pathname, int flags)
>  	return -EOPNOTSUPP;
>  }
>  
> -static inline struct net_device  *__dev_map_lookup_elem(struct bpf_map *map,
> -						       u32 key)
> +static inline void  *__dev_map_lookup_elem(struct bpf_map *map, u32 key)
>  {
>  	return NULL;
>  }
>  
> -static inline struct net_device  *__dev_map_hash_lookup_elem(struct bpf_map *map,
> -							     u32 key)
> +static inline void  *__dev_map_hash_lookup_elem(struct bpf_map *map, u32 key)
>  {
>  	return NULL;
>  }
> @@ -1615,7 +1617,7 @@ static inline int dev_map_generic_redirect(struct bpf_dtab_netdev *dst,
>  }
>  
>  static inline
> -struct bpf_cpu_map_entry *__cpu_map_lookup_elem(struct bpf_map *map, u32 key)
> +void *__cpu_map_lookup_elem(struct bpf_map *map, u32 key)
>  {
>  	return NULL;
>  }
> diff --git a/include/linux/filter.h b/include/linux/filter.h
> index 3b00fc906ccd..1dedcf66b694 100644
> --- a/include/linux/filter.h
> +++ b/include/linux/filter.h
> @@ -1472,4 +1472,6 @@ static inline bool bpf_sk_lookup_run_v6(struct net *net, int protocol,
>  }
>  #endif /* IS_ENABLED(CONFIG_IPV6) */
>  
> +bpf_func_proto_func get_xdp_redirect_func(enum bpf_map_type map_type);
> +
>  #endif /* __LINUX_FILTER_H__ */
> diff --git a/include/net/xdp_sock.h b/include/net/xdp_sock.h
> index cc17bc957548..da4139a58630 100644
> --- a/include/net/xdp_sock.h
> +++ b/include/net/xdp_sock.h
> @@ -80,8 +80,7 @@ int xsk_generic_rcv(struct xdp_sock *xs, struct xdp_buff *xdp);
>  int __xsk_map_redirect(struct xdp_sock *xs, struct xdp_buff *xdp);
>  void __xsk_map_flush(void);
>  
> -static inline struct xdp_sock *__xsk_map_lookup_elem(struct bpf_map *map,
> -						     u32 key)
> +static inline void *__xsk_map_lookup_elem(struct bpf_map *map, u32 key)
>  {
>  	struct xsk_map *m = container_of(map, struct xsk_map, map);
>  	struct xdp_sock *xs;
> @@ -109,8 +108,7 @@ static inline void __xsk_map_flush(void)
>  {
>  }
>  
> -static inline struct xdp_sock *__xsk_map_lookup_elem(struct bpf_map *map,
> -						     u32 key)
> +static inline void *__xsk_map_lookup_elem(struct bpf_map *map, u32 key)
>  {
>  	return NULL;
>  }
> diff --git a/kernel/bpf/cpumap.c b/kernel/bpf/cpumap.c
> index 5d1469de6921..a4d2cb93cd69 100644
> --- a/kernel/bpf/cpumap.c
> +++ b/kernel/bpf/cpumap.c
> @@ -563,7 +563,7 @@ static void cpu_map_free(struct bpf_map *map)
>  	kfree(cmap);
>  }
>  
> -struct bpf_cpu_map_entry *__cpu_map_lookup_elem(struct bpf_map *map, u32 key)
> +void *__cpu_map_lookup_elem(struct bpf_map *map, u32 key)
>  {
>  	struct bpf_cpu_map *cmap = container_of(map, struct bpf_cpu_map, map);
>  	struct bpf_cpu_map_entry *rcpu;
> diff --git a/kernel/bpf/devmap.c b/kernel/bpf/devmap.c
> index 85d9d1b72a33..37ac4cde9713 100644
> --- a/kernel/bpf/devmap.c
> +++ b/kernel/bpf/devmap.c
> @@ -258,7 +258,7 @@ static int dev_map_get_next_key(struct bpf_map *map, void *key, void *next_key)
>  	return 0;
>  }
>  
> -struct bpf_dtab_netdev *__dev_map_hash_lookup_elem(struct bpf_map *map, u32 key)
> +void *__dev_map_hash_lookup_elem(struct bpf_map *map, u32 key)
>  {
>  	struct bpf_dtab *dtab = container_of(map, struct bpf_dtab, map);
>  	struct hlist_head *head = dev_map_index_hash(dtab, key);
> @@ -392,7 +392,7 @@ void __dev_flush(void)
>   * update happens in parallel here a dev_put wont happen until after reading the
>   * ifindex.
>   */
> -struct bpf_dtab_netdev *__dev_map_lookup_elem(struct bpf_map *map, u32 key)
> +void *__dev_map_lookup_elem(struct bpf_map *map, u32 key)
>  {
>  	struct bpf_dtab *dtab = container_of(map, struct bpf_dtab, map);
>  	struct bpf_dtab_netdev *obj;
> diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
> index 3d34ba492d46..b5fb0c4e911a 100644
> --- a/kernel/bpf/verifier.c
> +++ b/kernel/bpf/verifier.c
> @@ -5409,7 +5409,8 @@ record_func_map(struct bpf_verifier_env *env, struct bpf_call_arg_meta *meta,
>  	    func_id != BPF_FUNC_map_delete_elem &&
>  	    func_id != BPF_FUNC_map_push_elem &&
>  	    func_id != BPF_FUNC_map_pop_elem &&
> -	    func_id != BPF_FUNC_map_peek_elem)
> +	    func_id != BPF_FUNC_map_peek_elem &&
> +	    func_id != BPF_FUNC_redirect_map)
>  		return 0;
>  
>  	if (map == NULL) {
> @@ -11860,17 +11861,22 @@ static int fixup_bpf_calls(struct bpf_verifier_env *env)
>  		}
>  
>  patch_call_imm:
> -		fn = env->ops->get_func_proto(insn->imm, env->prog);
> -		/* all functions that have prototype and verifier allowed
> -		 * programs to call them, must be real in-kernel functions
> -		 */
> -		if (!fn->func) {
> -			verbose(env,
> -				"kernel subsystem misconfigured func %s#%d\n",
> -				func_id_name(insn->imm), insn->imm);
> -			return -EFAULT;
> +		if (insn->imm == BPF_FUNC_redirect_map) {
> +			aux = &env->insn_aux_data[i];
> +			map_ptr = BPF_MAP_PTR(aux->map_ptr_state);
> +			insn->imm = get_xdp_redirect_func(map_ptr->map_type) - __bpf_call_base;
> +		} else {
> +			fn = env->ops->get_func_proto(insn->imm, env->prog);
> +			/* all functions that have prototype and verifier allowed
> +			 * programs to call them, must be real in-kernel functions
> +			 */
> +			if (!fn->func) {
> +				verbose(env, "kernel subsystem misconfigured func %s#%d\n",
> +					func_id_name(insn->imm), insn->imm);
> +				return -EFAULT;
> +			}
> +			insn->imm = fn->func - __bpf_call_base;
>  		}
> -		insn->imm = fn->func - __bpf_call_base;
>  	}
>  
>  	/* Since poke tab is now finalized, publish aux to tracker. */
> diff --git a/net/core/filter.c b/net/core/filter.c
> index adfdad234674..fd64d768e16a 100644
> --- a/net/core/filter.c
> +++ b/net/core/filter.c
> @@ -3944,22 +3944,6 @@ void xdp_do_flush(void)
>  }
>  EXPORT_SYMBOL_GPL(xdp_do_flush);
>  
> -static inline void *__xdp_map_lookup_elem(struct bpf_map *map, u32 index)
> -{
> -	switch (map->map_type) {
> -	case BPF_MAP_TYPE_DEVMAP:
> -		return __dev_map_lookup_elem(map, index);
> -	case BPF_MAP_TYPE_DEVMAP_HASH:
> -		return __dev_map_hash_lookup_elem(map, index);
> -	case BPF_MAP_TYPE_CPUMAP:
> -		return __cpu_map_lookup_elem(map, index);
> -	case BPF_MAP_TYPE_XSKMAP:
> -		return __xsk_map_lookup_elem(map, index);
> -	default:
> -		return NULL;
> -	}
> -}
> -
>  void bpf_clear_redirect_map(struct bpf_map *map)
>  {
>  	struct bpf_redirect_info *ri;
> @@ -4110,22 +4094,17 @@ static const struct bpf_func_proto bpf_xdp_redirect_proto = {
>  	.arg2_type      = ARG_ANYTHING,
>  };
>  
> -BPF_CALL_3(bpf_xdp_redirect_map, struct bpf_map *, map, u32, ifindex,
> -	   u64, flags)
> +static __always_inline s64 __bpf_xdp_redirect_map(struct bpf_map *map, u32 ifindex, u64 flags,
> +						  void *lookup_elem(struct bpf_map *map,
> +								    u32 key))
>  {
>  	struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
>  
> -	/* Lower bits of the flags are used as return code on lookup failure */
>  	if (unlikely(flags > XDP_TX))
>  		return XDP_ABORTED;
>  
> -	ri->tgt_value = __xdp_map_lookup_elem(map, ifindex);
> +	ri->tgt_value = lookup_elem(map, ifindex);
>  	if (unlikely(!ri->tgt_value)) {
> -		/* If the lookup fails we want to clear out the state in the
> -		 * redirect_info struct completely, so that if an eBPF program
> -		 * performs multiple lookups, the last one always takes
> -		 * precedence.
> -		 */

Why remove the comments?

>  		WRITE_ONCE(ri->map, NULL);
>  		return flags;
>  	}
> @@ -4137,8 +4116,44 @@ BPF_CALL_3(bpf_xdp_redirect_map, struct bpf_map *, map, u32, ifindex,
>  	return XDP_REDIRECT;
>  }
>  
> +BPF_CALL_3(bpf_xdp_redirect_devmap, struct bpf_map *, map, u32, ifindex, u64, flags)
> +{
> +	return __bpf_xdp_redirect_map(map, ifindex, flags, __dev_map_lookup_elem);
> +}
> +
> +BPF_CALL_3(bpf_xdp_redirect_devmap_hash, struct bpf_map *, map, u32, ifindex, u64, flags)
> +{
> +	return __bpf_xdp_redirect_map(map, ifindex, flags, __dev_map_hash_lookup_elem);
> +}
> +
> +BPF_CALL_3(bpf_xdp_redirect_cpumap, struct bpf_map *, map, u32, ifindex, u64, flags)
> +{
> +	return __bpf_xdp_redirect_map(map, ifindex, flags, __cpu_map_lookup_elem);
> +}
> +
> +BPF_CALL_3(bpf_xdp_redirect_xskmap, struct bpf_map *, map, u32, ifindex, u64, flags)
> +{
> +	return __bpf_xdp_redirect_map(map, ifindex, flags, __xsk_map_lookup_elem);
> +}
> +
> +bpf_func_proto_func get_xdp_redirect_func(enum bpf_map_type map_type)
> +{
> +	switch (map_type) {
> +	case BPF_MAP_TYPE_DEVMAP:
> +		return bpf_xdp_redirect_devmap;
> +	case BPF_MAP_TYPE_DEVMAP_HASH:
> +		return bpf_xdp_redirect_devmap_hash;
> +	case BPF_MAP_TYPE_CPUMAP:
> +		return bpf_xdp_redirect_cpumap;
> +	case BPF_MAP_TYPE_XSKMAP:
> +		return bpf_xdp_redirect_xskmap;
> +	default:
> +		return NULL;
> +	}
> +}
> +
> +/* NB! .func is NULL! get_xdp_redirect_func() is used instead! */
>  static const struct bpf_func_proto bpf_xdp_redirect_map_proto = {
> -	.func           = bpf_xdp_redirect_map,
>  	.gpl_only       = false,
>  	.ret_type       = RET_INTEGER,
>  	.arg1_type      = ARG_CONST_MAP_PTR,
> -- 
> 2.27.0
kernel test robot Feb. 19, 2021, 5:08 p.m. UTC | #2 
Hi "Björn,

I love your patch! Perhaps something to improve:

[auto build test WARNING on 7b1e385c9a488de9291eaaa412146d3972e9dec5]

url:    https://github.com/0day-ci/linux/commits/Bj-rn-T-pel/Optimize-bpf_redirect_map-xdp_do_redirect/20210219-230349
base:   7b1e385c9a488de9291eaaa412146d3972e9dec5
config: nds32-randconfig-r006-20210219 (attached as .config)
compiler: nds32le-linux-gcc (GCC) 9.3.0
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # https://github.com/0day-ci/linux/commit/e784328ffb3b588155aeee02ff6a96b4a6b7cf20
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Bj-rn-T-pel/Optimize-bpf_redirect_map-xdp_do_redirect/20210219-230349
        git checkout e784328ffb3b588155aeee02ff6a96b4a6b7cf20
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=nds32 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All warnings (new ones prefixed by >>):

   In file included from include/linux/bpf-cgroup.h:5,
                    from include/linux/cgroup-defs.h:22,
                    from include/linux/cgroup.h:28,
                    from include/linux/hugetlb.h:9,
                    from kernel/events/core.c:31:
>> include/linux/bpf.h:1629:42: warning: 'struct bpf_cpu_map_entry' declared inside parameter list will not be visible outside of this definition or declaration
    1629 | static inline int cpu_map_enqueue(struct bpf_cpu_map_entry *rcpu,
         |                                          ^~~~~~~~~~~~~~~~~
   kernel/events/core.c:6539:6: warning: no previous prototype for 'perf_pmu_snapshot_aux' [-Wmissing-prototypes]
    6539 | long perf_pmu_snapshot_aux(struct perf_buffer *rb,
         |      ^~~~~~~~~~~~~~~~~~~~~
--
   In file included from include/linux/bpf-cgroup.h:5,
                    from include/linux/cgroup-defs.h:22,
                    from include/linux/cgroup.h:28,
                    from include/linux/perf_event.h:57,
                    from kernel/events/ring_buffer.c:11:
>> include/linux/bpf.h:1629:42: warning: 'struct bpf_cpu_map_entry' declared inside parameter list will not be visible outside of this definition or declaration
    1629 | static inline int cpu_map_enqueue(struct bpf_cpu_map_entry *rcpu,
         |                                          ^~~~~~~~~~~~~~~~~


vim +1629 include/linux/bpf.h

9c270af37bb62e Jesper Dangaard Brouer 2017-10-16  1628  
9c270af37bb62e Jesper Dangaard Brouer 2017-10-16 @1629  static inline int cpu_map_enqueue(struct bpf_cpu_map_entry *rcpu,
9c270af37bb62e Jesper Dangaard Brouer 2017-10-16  1630  				  struct xdp_buff *xdp,
9c270af37bb62e Jesper Dangaard Brouer 2017-10-16  1631  				  struct net_device *dev_rx)
9c270af37bb62e Jesper Dangaard Brouer 2017-10-16  1632  {
9c270af37bb62e Jesper Dangaard Brouer 2017-10-16  1633  	return 0;
9c270af37bb62e Jesper Dangaard Brouer 2017-10-16  1634  }
040ee69226f8a9 Al Viro                2017-12-02  1635  

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
Björn Töpel Feb. 19, 2021, 5:47 p.m. UTC | #3 
On 2021-02-19 18:05, Toke Høiland-Jørgensen wrote:
> Björn Töpel <bjorn.topel@gmail.com> writes:
> 

[...]


>> @@ -4110,22 +4094,17 @@ static const struct bpf_func_proto bpf_xdp_redirect_proto = {
>>   	.arg2_type      = ARG_ANYTHING,
>>   };
>>   
>> -BPF_CALL_3(bpf_xdp_redirect_map, struct bpf_map *, map, u32, ifindex,
>> -	   u64, flags)
>> +static __always_inline s64 __bpf_xdp_redirect_map(struct bpf_map *map, u32 ifindex, u64 flags,
>> +						  void *lookup_elem(struct bpf_map *map,
>> +								    u32 key))
>>   {
>>   	struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
>>   
>> -	/* Lower bits of the flags are used as return code on lookup failure */
>>   	if (unlikely(flags > XDP_TX))
>>   		return XDP_ABORTED;
>>   
>> -	ri->tgt_value = __xdp_map_lookup_elem(map, ifindex);
>> +	ri->tgt_value = lookup_elem(map, ifindex);
>>   	if (unlikely(!ri->tgt_value)) {
>> -		/* If the lookup fails we want to clear out the state in the
>> -		 * redirect_info struct completely, so that if an eBPF program
>> -		 * performs multiple lookups, the last one always takes
>> -		 * precedence.
>> -		 */
> 
> Why remove the comments?
>

Ugh, no reason. I'll do a v2. LKP had a warning as well.


Thanks,
Björn

[...]
kernel test robot Feb. 19, 2021, 6:13 p.m. UTC | #4 
Hi "Björn,

I love your patch! Yet something to improve:

[auto build test ERROR on 7b1e385c9a488de9291eaaa412146d3972e9dec5]

url:    https://github.com/0day-ci/linux/commits/Bj-rn-T-pel/Optimize-bpf_redirect_map-xdp_do_redirect/20210219-230349
base:   7b1e385c9a488de9291eaaa412146d3972e9dec5
config: x86_64-randconfig-r032-20210219 (attached as .config)
compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project c9439ca36342fb6013187d0a69aef92736951476)
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # install x86_64 cross compiling tool for clang build
        # apt-get install binutils-x86-64-linux-gnu
        # https://github.com/0day-ci/linux/commit/e784328ffb3b588155aeee02ff6a96b4a6b7cf20
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Bj-rn-T-pel/Optimize-bpf_redirect_map-xdp_do_redirect/20210219-230349
        git checkout e784328ffb3b588155aeee02ff6a96b4a6b7cf20
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=x86_64 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All error/warnings (new ones prefixed by >>):

   In file included from arch/x86/kernel/asm-offsets.c:13:
   In file included from include/linux/suspend.h:5:
   In file included from include/linux/swap.h:9:
   In file included from include/linux/memcontrol.h:13:
   In file included from include/linux/cgroup.h:28:
   In file included from include/linux/cgroup-defs.h:22:
   In file included from include/linux/bpf-cgroup.h:5:
>> include/linux/bpf.h:1629:42: warning: declaration of 'struct bpf_cpu_map_entry' will not be visible outside of this function [-Wvisibility]
   static inline int cpu_map_enqueue(struct bpf_cpu_map_entry *rcpu,
                                            ^
   1 warning generated.
--
   In file included from arch/x86/mm/ioremap.c:23:
   In file included from arch/x86/include/asm/efi.h:7:
   In file included from arch/x86/include/asm/tlb.h:12:
   In file included from include/asm-generic/tlb.h:15:
   In file included from include/linux/swap.h:9:
   In file included from include/linux/memcontrol.h:13:
   In file included from include/linux/cgroup.h:28:
   In file included from include/linux/cgroup-defs.h:22:
   In file included from include/linux/bpf-cgroup.h:5:
>> include/linux/bpf.h:1629:42: warning: declaration of 'struct bpf_cpu_map_entry' will not be visible outside of this function [-Wvisibility]
   static inline int cpu_map_enqueue(struct bpf_cpu_map_entry *rcpu,
                                            ^
   arch/x86/mm/ioremap.c:737:17: warning: no previous prototype for function 'early_memremap_pgprot_adjust' [-Wmissing-prototypes]
   pgprot_t __init early_memremap_pgprot_adjust(resource_size_t phys_addr,
                   ^
   arch/x86/mm/ioremap.c:737:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
   pgprot_t __init early_memremap_pgprot_adjust(resource_size_t phys_addr,
   ^
   static 
   2 warnings generated.
--
   In file included from arch/x86/mm/extable.c:9:
   In file included from arch/x86/include/asm/traps.h:9:
   In file included from arch/x86/include/asm/idtentry.h:9:
   In file included from include/linux/entry-common.h:5:
   In file included from include/linux/tracehook.h:50:
   In file included from include/linux/memcontrol.h:13:
   In file included from include/linux/cgroup.h:28:
   In file included from include/linux/cgroup-defs.h:22:
   In file included from include/linux/bpf-cgroup.h:5:
>> include/linux/bpf.h:1629:42: warning: declaration of 'struct bpf_cpu_map_entry' will not be visible outside of this function [-Wvisibility]
   static inline int cpu_map_enqueue(struct bpf_cpu_map_entry *rcpu,
                                            ^
   arch/x86/mm/extable.c:27:16: warning: no previous prototype for function 'ex_handler_default' [-Wmissing-prototypes]
   __visible bool ex_handler_default(const struct exception_table_entry *fixup,
                  ^
   arch/x86/mm/extable.c:27:11: note: declare 'static' if the function is not intended to be used outside of this translation unit
   __visible bool ex_handler_default(const struct exception_table_entry *fixup,
             ^
             static 
   arch/x86/mm/extable.c:37:16: warning: no previous prototype for function 'ex_handler_fault' [-Wmissing-prototypes]
   __visible bool ex_handler_fault(const struct exception_table_entry *fixup,
                  ^
   arch/x86/mm/extable.c:37:11: note: declare 'static' if the function is not intended to be used outside of this translation unit
   __visible bool ex_handler_fault(const struct exception_table_entry *fixup,
             ^
             static 
   arch/x86/mm/extable.c:58:16: warning: no previous prototype for function 'ex_handler_fprestore' [-Wmissing-prototypes]
   __visible bool ex_handler_fprestore(const struct exception_table_entry *fixup,
                  ^
   arch/x86/mm/extable.c:58:11: note: declare 'static' if the function is not intended to be used outside of this translation unit
   __visible bool ex_handler_fprestore(const struct exception_table_entry *fixup,
             ^
             static 
   arch/x86/mm/extable.c:73:16: warning: no previous prototype for function 'ex_handler_uaccess' [-Wmissing-prototypes]
   __visible bool ex_handler_uaccess(const struct exception_table_entry *fixup,
                  ^
   arch/x86/mm/extable.c:73:11: note: declare 'static' if the function is not intended to be used outside of this translation unit
   __visible bool ex_handler_uaccess(const struct exception_table_entry *fixup,
             ^
             static 
   arch/x86/mm/extable.c:84:16: warning: no previous prototype for function 'ex_handler_copy' [-Wmissing-prototypes]
   __visible bool ex_handler_copy(const struct exception_table_entry *fixup,
                  ^
   arch/x86/mm/extable.c:84:11: note: declare 'static' if the function is not intended to be used outside of this translation unit
   __visible bool ex_handler_copy(const struct exception_table_entry *fixup,
             ^
             static 
   arch/x86/mm/extable.c:96:16: warning: no previous prototype for function 'ex_handler_rdmsr_unsafe' [-Wmissing-prototypes]
   __visible bool ex_handler_rdmsr_unsafe(const struct exception_table_entry *fixup,
                  ^
   arch/x86/mm/extable.c:96:11: note: declare 'static' if the function is not intended to be used outside of this translation unit
   __visible bool ex_handler_rdmsr_unsafe(const struct exception_table_entry *fixup,
             ^
             static 
   arch/x86/mm/extable.c:113:16: warning: no previous prototype for function 'ex_handler_wrmsr_unsafe' [-Wmissing-prototypes]
   __visible bool ex_handler_wrmsr_unsafe(const struct exception_table_entry *fixup,
                  ^
   arch/x86/mm/extable.c:113:11: note: declare 'static' if the function is not intended to be used outside of this translation unit
   __visible bool ex_handler_wrmsr_unsafe(const struct exception_table_entry *fixup,
             ^
             static 
   arch/x86/mm/extable.c:129:16: warning: no previous prototype for function 'ex_handler_clear_fs' [-Wmissing-prototypes]
   __visible bool ex_handler_clear_fs(const struct exception_table_entry *fixup,
                  ^
   arch/x86/mm/extable.c:129:11: note: declare 'static' if the function is not intended to be used outside of this translation unit
   __visible bool ex_handler_clear_fs(const struct exception_table_entry *fixup,
             ^
             static 
   9 warnings generated.
--
   In file included from <built-in>:3:
   In file included from drivers/gpu/drm/i915/display/intel_cdclk.h:11:
   In file included from drivers/gpu/drm/i915/i915_drv.h:46:
   In file included from include/linux/perf_event.h:57:
   In file included from include/linux/cgroup.h:28:
   In file included from include/linux/cgroup-defs.h:22:
   In file included from include/linux/bpf-cgroup.h:5:
>> include/linux/bpf.h:1629:42: error: declaration of 'struct bpf_cpu_map_entry' will not be visible outside of this function [-Werror,-Wvisibility]
   static inline int cpu_map_enqueue(struct bpf_cpu_map_entry *rcpu,
                                            ^
   1 error generated.
--
   In file included from arch/x86/kernel/asm-offsets.c:13:
   In file included from include/linux/suspend.h:5:
   In file included from include/linux/swap.h:9:
   In file included from include/linux/memcontrol.h:13:
   In file included from include/linux/cgroup.h:28:
   In file included from include/linux/cgroup-defs.h:22:
   In file included from include/linux/bpf-cgroup.h:5:
>> include/linux/bpf.h:1629:42: warning: declaration of 'struct bpf_cpu_map_entry' will not be visible outside of this function [-Wvisibility]
   static inline int cpu_map_enqueue(struct bpf_cpu_map_entry *rcpu,
                                            ^
   1 warning generated.


vim +1629 include/linux/bpf.h

9c270af37bb62e Jesper Dangaard Brouer 2017-10-16  1628  
9c270af37bb62e Jesper Dangaard Brouer 2017-10-16 @1629  static inline int cpu_map_enqueue(struct bpf_cpu_map_entry *rcpu,
9c270af37bb62e Jesper Dangaard Brouer 2017-10-16  1630  				  struct xdp_buff *xdp,
9c270af37bb62e Jesper Dangaard Brouer 2017-10-16  1631  				  struct net_device *dev_rx)
9c270af37bb62e Jesper Dangaard Brouer 2017-10-16  1632  {
9c270af37bb62e Jesper Dangaard Brouer 2017-10-16  1633  	return 0;
9c270af37bb62e Jesper Dangaard Brouer 2017-10-16  1634  }
040ee69226f8a9 Al Viro                2017-12-02  1635  

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
diff mbox series

Patch

diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index cccaef1088ea..3dd186eeaf98 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -314,12 +314,14 @@  enum bpf_return_type {
 	RET_PTR_TO_BTF_ID,		/* returns a pointer to a btf_id */
 };
 
+typedef u64 (*bpf_func_proto_func)(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5);
+
 /* eBPF function prototype used by verifier to allow BPF_CALLs from eBPF programs
  * to in-kernel helper functions and for adjusting imm32 field in BPF_CALL
  * instructions after verifying
  */
 struct bpf_func_proto {
-	u64 (*func)(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5);
+	bpf_func_proto_func func;
 	bool gpl_only;
 	bool pkt_access;
 	enum bpf_return_type ret_type;
@@ -1429,9 +1431,11 @@  struct btf *bpf_get_btf_vmlinux(void);
 /* Map specifics */
 struct xdp_buff;
 struct sk_buff;
+struct bpf_dtab_netdev;
+struct bpf_cpu_map_entry;
 
-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_lookup_elem(struct bpf_map *map, u32 key);
+void *__dev_map_hash_lookup_elem(struct bpf_map *map, u32 key);
 void __dev_flush(void);
 int dev_xdp_enqueue(struct net_device *dev, struct xdp_buff *xdp,
 		    struct net_device *dev_rx);
@@ -1441,7 +1445,7 @@  int dev_map_generic_redirect(struct bpf_dtab_netdev *dst, struct sk_buff *skb,
 			     struct bpf_prog *xdp_prog);
 bool dev_map_can_have_prog(struct bpf_map *map);
 
-struct bpf_cpu_map_entry *__cpu_map_lookup_elem(struct bpf_map *map, u32 key);
+void *__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);
@@ -1568,14 +1572,12 @@  static inline int bpf_obj_get_user(const char __user *pathname, int flags)
 	return -EOPNOTSUPP;
 }
 
-static inline struct net_device  *__dev_map_lookup_elem(struct bpf_map *map,
-						       u32 key)
+static inline void  *__dev_map_lookup_elem(struct bpf_map *map, u32 key)
 {
 	return NULL;
 }
 
-static inline struct net_device  *__dev_map_hash_lookup_elem(struct bpf_map *map,
-							     u32 key)
+static inline void  *__dev_map_hash_lookup_elem(struct bpf_map *map, u32 key)
 {
 	return NULL;
 }
@@ -1615,7 +1617,7 @@  static inline int dev_map_generic_redirect(struct bpf_dtab_netdev *dst,
 }
 
 static inline
-struct bpf_cpu_map_entry *__cpu_map_lookup_elem(struct bpf_map *map, u32 key)
+void *__cpu_map_lookup_elem(struct bpf_map *map, u32 key)
 {
 	return NULL;
 }
diff --git a/include/linux/filter.h b/include/linux/filter.h
index 3b00fc906ccd..1dedcf66b694 100644
--- a/include/linux/filter.h
+++ b/include/linux/filter.h
@@ -1472,4 +1472,6 @@  static inline bool bpf_sk_lookup_run_v6(struct net *net, int protocol,
 }
 #endif /* IS_ENABLED(CONFIG_IPV6) */
 
+bpf_func_proto_func get_xdp_redirect_func(enum bpf_map_type map_type);
+
 #endif /* __LINUX_FILTER_H__ */
diff --git a/include/net/xdp_sock.h b/include/net/xdp_sock.h
index cc17bc957548..da4139a58630 100644
--- a/include/net/xdp_sock.h
+++ b/include/net/xdp_sock.h
@@ -80,8 +80,7 @@  int xsk_generic_rcv(struct xdp_sock *xs, struct xdp_buff *xdp);
 int __xsk_map_redirect(struct xdp_sock *xs, struct xdp_buff *xdp);
 void __xsk_map_flush(void);
 
-static inline struct xdp_sock *__xsk_map_lookup_elem(struct bpf_map *map,
-						     u32 key)
+static inline void *__xsk_map_lookup_elem(struct bpf_map *map, u32 key)
 {
 	struct xsk_map *m = container_of(map, struct xsk_map, map);
 	struct xdp_sock *xs;
@@ -109,8 +108,7 @@  static inline void __xsk_map_flush(void)
 {
 }
 
-static inline struct xdp_sock *__xsk_map_lookup_elem(struct bpf_map *map,
-						     u32 key)
+static inline void *__xsk_map_lookup_elem(struct bpf_map *map, u32 key)
 {
 	return NULL;
 }
diff --git a/kernel/bpf/cpumap.c b/kernel/bpf/cpumap.c
index 5d1469de6921..a4d2cb93cd69 100644
--- a/kernel/bpf/cpumap.c
+++ b/kernel/bpf/cpumap.c
@@ -563,7 +563,7 @@  static void cpu_map_free(struct bpf_map *map)
 	kfree(cmap);
 }
 
-struct bpf_cpu_map_entry *__cpu_map_lookup_elem(struct bpf_map *map, u32 key)
+void *__cpu_map_lookup_elem(struct bpf_map *map, u32 key)
 {
 	struct bpf_cpu_map *cmap = container_of(map, struct bpf_cpu_map, map);
 	struct bpf_cpu_map_entry *rcpu;
diff --git a/kernel/bpf/devmap.c b/kernel/bpf/devmap.c
index 85d9d1b72a33..37ac4cde9713 100644
--- a/kernel/bpf/devmap.c
+++ b/kernel/bpf/devmap.c
@@ -258,7 +258,7 @@  static int dev_map_get_next_key(struct bpf_map *map, void *key, void *next_key)
 	return 0;
 }
 
-struct bpf_dtab_netdev *__dev_map_hash_lookup_elem(struct bpf_map *map, u32 key)
+void *__dev_map_hash_lookup_elem(struct bpf_map *map, u32 key)
 {
 	struct bpf_dtab *dtab = container_of(map, struct bpf_dtab, map);
 	struct hlist_head *head = dev_map_index_hash(dtab, key);
@@ -392,7 +392,7 @@  void __dev_flush(void)
  * update happens in parallel here a dev_put wont happen until after reading the
  * ifindex.
  */
-struct bpf_dtab_netdev *__dev_map_lookup_elem(struct bpf_map *map, u32 key)
+void *__dev_map_lookup_elem(struct bpf_map *map, u32 key)
 {
 	struct bpf_dtab *dtab = container_of(map, struct bpf_dtab, map);
 	struct bpf_dtab_netdev *obj;
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 3d34ba492d46..b5fb0c4e911a 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -5409,7 +5409,8 @@  record_func_map(struct bpf_verifier_env *env, struct bpf_call_arg_meta *meta,
 	    func_id != BPF_FUNC_map_delete_elem &&
 	    func_id != BPF_FUNC_map_push_elem &&
 	    func_id != BPF_FUNC_map_pop_elem &&
-	    func_id != BPF_FUNC_map_peek_elem)
+	    func_id != BPF_FUNC_map_peek_elem &&
+	    func_id != BPF_FUNC_redirect_map)
 		return 0;
 
 	if (map == NULL) {
@@ -11860,17 +11861,22 @@  static int fixup_bpf_calls(struct bpf_verifier_env *env)
 		}
 
 patch_call_imm:
-		fn = env->ops->get_func_proto(insn->imm, env->prog);
-		/* all functions that have prototype and verifier allowed
-		 * programs to call them, must be real in-kernel functions
-		 */
-		if (!fn->func) {
-			verbose(env,
-				"kernel subsystem misconfigured func %s#%d\n",
-				func_id_name(insn->imm), insn->imm);
-			return -EFAULT;
+		if (insn->imm == BPF_FUNC_redirect_map) {
+			aux = &env->insn_aux_data[i];
+			map_ptr = BPF_MAP_PTR(aux->map_ptr_state);
+			insn->imm = get_xdp_redirect_func(map_ptr->map_type) - __bpf_call_base;
+		} else {
+			fn = env->ops->get_func_proto(insn->imm, env->prog);
+			/* all functions that have prototype and verifier allowed
+			 * programs to call them, must be real in-kernel functions
+			 */
+			if (!fn->func) {
+				verbose(env, "kernel subsystem misconfigured func %s#%d\n",
+					func_id_name(insn->imm), insn->imm);
+				return -EFAULT;
+			}
+			insn->imm = fn->func - __bpf_call_base;
 		}
-		insn->imm = fn->func - __bpf_call_base;
 	}
 
 	/* Since poke tab is now finalized, publish aux to tracker. */
diff --git a/net/core/filter.c b/net/core/filter.c
index adfdad234674..fd64d768e16a 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -3944,22 +3944,6 @@  void xdp_do_flush(void)
 }
 EXPORT_SYMBOL_GPL(xdp_do_flush);
 
-static inline void *__xdp_map_lookup_elem(struct bpf_map *map, u32 index)
-{
-	switch (map->map_type) {
-	case BPF_MAP_TYPE_DEVMAP:
-		return __dev_map_lookup_elem(map, index);
-	case BPF_MAP_TYPE_DEVMAP_HASH:
-		return __dev_map_hash_lookup_elem(map, index);
-	case BPF_MAP_TYPE_CPUMAP:
-		return __cpu_map_lookup_elem(map, index);
-	case BPF_MAP_TYPE_XSKMAP:
-		return __xsk_map_lookup_elem(map, index);
-	default:
-		return NULL;
-	}
-}
-
 void bpf_clear_redirect_map(struct bpf_map *map)
 {
 	struct bpf_redirect_info *ri;
@@ -4110,22 +4094,17 @@  static const struct bpf_func_proto bpf_xdp_redirect_proto = {
 	.arg2_type      = ARG_ANYTHING,
 };
 
-BPF_CALL_3(bpf_xdp_redirect_map, struct bpf_map *, map, u32, ifindex,
-	   u64, flags)
+static __always_inline s64 __bpf_xdp_redirect_map(struct bpf_map *map, u32 ifindex, u64 flags,
+						  void *lookup_elem(struct bpf_map *map,
+								    u32 key))
 {
 	struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
 
-	/* Lower bits of the flags are used as return code on lookup failure */
 	if (unlikely(flags > XDP_TX))
 		return XDP_ABORTED;
 
-	ri->tgt_value = __xdp_map_lookup_elem(map, ifindex);
+	ri->tgt_value = lookup_elem(map, ifindex);
 	if (unlikely(!ri->tgt_value)) {
-		/* If the lookup fails we want to clear out the state in the
-		 * redirect_info struct completely, so that if an eBPF program
-		 * performs multiple lookups, the last one always takes
-		 * precedence.
-		 */
 		WRITE_ONCE(ri->map, NULL);
 		return flags;
 	}
@@ -4137,8 +4116,44 @@  BPF_CALL_3(bpf_xdp_redirect_map, struct bpf_map *, map, u32, ifindex,
 	return XDP_REDIRECT;
 }
 
+BPF_CALL_3(bpf_xdp_redirect_devmap, struct bpf_map *, map, u32, ifindex, u64, flags)
+{
+	return __bpf_xdp_redirect_map(map, ifindex, flags, __dev_map_lookup_elem);
+}
+
+BPF_CALL_3(bpf_xdp_redirect_devmap_hash, struct bpf_map *, map, u32, ifindex, u64, flags)
+{
+	return __bpf_xdp_redirect_map(map, ifindex, flags, __dev_map_hash_lookup_elem);
+}
+
+BPF_CALL_3(bpf_xdp_redirect_cpumap, struct bpf_map *, map, u32, ifindex, u64, flags)
+{
+	return __bpf_xdp_redirect_map(map, ifindex, flags, __cpu_map_lookup_elem);
+}
+
+BPF_CALL_3(bpf_xdp_redirect_xskmap, struct bpf_map *, map, u32, ifindex, u64, flags)
+{
+	return __bpf_xdp_redirect_map(map, ifindex, flags, __xsk_map_lookup_elem);
+}
+
+bpf_func_proto_func get_xdp_redirect_func(enum bpf_map_type map_type)
+{
+	switch (map_type) {
+	case BPF_MAP_TYPE_DEVMAP:
+		return bpf_xdp_redirect_devmap;
+	case BPF_MAP_TYPE_DEVMAP_HASH:
+		return bpf_xdp_redirect_devmap_hash;
+	case BPF_MAP_TYPE_CPUMAP:
+		return bpf_xdp_redirect_cpumap;
+	case BPF_MAP_TYPE_XSKMAP:
+		return bpf_xdp_redirect_xskmap;
+	default:
+		return NULL;
+	}
+}
+
+/* NB! .func is NULL! get_xdp_redirect_func() is used instead! */
 static const struct bpf_func_proto bpf_xdp_redirect_map_proto = {
-	.func           = bpf_xdp_redirect_map,
 	.gpl_only       = false,
 	.ret_type       = RET_INTEGER,
 	.arg1_type      = ARG_CONST_MAP_PTR,