| Message ID | 20241001050959.1799151-2-gnaaman@drivenets.com (mailing list archive) |
|---|---|
| State | Superseded |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | Improve neigh_flush_dev performance | expand |
On Tue, Oct 01, 2024 at 05:09:56AM +0000, Gilad Naaman wrote: > Use doubly-linked instead of singly-linked list when linking neighbours, > so that it is possible to remove neighbours without traversing the > entire table. > > Signed-off-by: Gilad Naaman <gnaaman@drivenets.com> Hi Gilad, This is not a full review, but rather some feedback to take into account once a proper review arrives. > --- > include/net/neighbour.h | 8 +-- > net/core/neighbour.c | 123 ++++++++++++++-------------------------- > 2 files changed, 45 insertions(+), 86 deletions(-) > > diff --git a/include/net/neighbour.h b/include/net/neighbour.h > index a44f262a7384..77a4aa53aecb 100644 > --- a/include/net/neighbour.h > +++ b/include/net/neighbour.h > @@ -135,7 +135,7 @@ struct neigh_statistics { > #define NEIGH_CACHE_STAT_INC(tbl, field) this_cpu_inc((tbl)->stats->field) > > struct neighbour { > - struct neighbour __rcu *next; > + struct hlist_node __rcu list; > struct neigh_table *tbl; > struct neigh_parms *parms; > unsigned long confirmed; Sparse is having a bit of a cow with rcu changes introduced by this patch. Please take a look at that. ...
Hi Gilad, kernel test robot noticed the following build warnings: [auto build test WARNING on net-next/main] url: https://github.com/intel-lab-lkp/linux/commits/Gilad-Naaman/Convert-neighbour-table-to-use-hlist/20241001-131234 base: net-next/main patch link: https://lore.kernel.org/r/20241001050959.1799151-2-gnaaman%40drivenets.com patch subject: [PATCH net-next 1/2] Convert neighbour-table to use hlist config: x86_64-randconfig-121-20241004 (https://download.01.org/0day-ci/archive/20241004/202410040908.loCFe95v-lkp@intel.com/config) compiler: clang version 18.1.8 (https://github.com/llvm/llvm-project 3b5b5c1ec4a3095ab096dd780e84d7ab81f3d7ff) reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20241004/202410040908.loCFe95v-lkp@intel.com/reproduce) If you fix the issue in a separate patch/commit (i.e. not just a new version of the same patch/commit), kindly add following tags | Reported-by: kernel test robot <lkp@intel.com> | Closes: https://lore.kernel.org/oe-kbuild-all/202410040908.loCFe95v-lkp@intel.com/ sparse warnings: (new ones prefixed by >>) >> net/core/neighbour.c:669:9: sparse: sparse: cast removes address space '__rcu' of expression >> net/core/neighbour.c:669:9: sparse: sparse: cast removes address space '__rcu' of expression >> net/core/neighbour.c:669:9: sparse: sparse: cast removes address space '__rcu' of expression >> net/core/neighbour.c:669:9: sparse: sparse: cast removes address space '__rcu' of expression >> net/core/neighbour.c:669:9: sparse: sparse: cast removes address space '__rcu' of expression >> net/core/neighbour.c:669:9: sparse: sparse: cast removes address space '__rcu' of expression >> net/core/neighbour.c:669:9: sparse: sparse: cast removes address space '__rcu' of expression >> net/core/neighbour.c:669:9: sparse: sparse: cast removes address space '__rcu' of expression >> net/core/neighbour.c:669:9: sparse: sparse: cast removes address space '__rcu' of expression >> net/core/neighbour.c:669:9: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:2698:17: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:2698:17: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:2698:17: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:2698:17: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:2698:17: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:2698:17: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:2698:17: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:2698:17: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:2698:17: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:2698:17: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:3065:17: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:3065:17: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:3065:17: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:3065:17: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:3065:17: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:3065:17: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:3065:17: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:3065:17: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:3065:17: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:3065:17: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:3164:17: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:3164:17: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:3164:17: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:3164:17: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:3164:17: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:3164:17: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:3164:17: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:3164:17: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:3164:17: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:3164:17: sparse: sparse: cast removes address space '__rcu' of expression >> net/core/neighbour.c:215:32: sparse: sparse: incorrect type in argument 1 (different modifiers) @@ expected struct hlist_node *n @@ got struct hlist_node [noderef] * @@ net/core/neighbour.c:215:32: sparse: expected struct hlist_node *n net/core/neighbour.c:215:32: sparse: got struct hlist_node [noderef] * net/core/neighbour.c:370:26: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:382:40: sparse: sparse: incorrect type in argument 1 (different modifiers) @@ expected struct hlist_node *n @@ got struct hlist_node [noderef] * @@ net/core/neighbour.c:382:40: sparse: expected struct hlist_node *n net/core/neighbour.c:382:40: sparse: got struct hlist_node [noderef] * >> net/core/neighbour.c:519:25: sparse: sparse: incorrect type in assignment (different address spaces) @@ expected struct hlist_head [noderef] __rcu *buckets @@ got void *_res @@ net/core/neighbour.c:519:25: sparse: expected struct hlist_head [noderef] __rcu *buckets net/core/neighbour.c:519:25: sparse: got void *_res >> net/core/neighbour.c:524:32: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected void const *ptr @@ got struct hlist_head [noderef] __rcu *[assigned] buckets @@ net/core/neighbour.c:524:32: sparse: expected void const *ptr net/core/neighbour.c:524:32: sparse: got struct hlist_head [noderef] __rcu *[assigned] buckets >> net/core/neighbour.c:546:23: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected void const *objp @@ got struct hlist_head [noderef] __rcu *buckets @@ net/core/neighbour.c:546:23: sparse: expected void const *objp net/core/neighbour.c:546:23: sparse: got struct hlist_head [noderef] __rcu *buckets >> net/core/neighbour.c:548:31: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected void const *ptr @@ got struct hlist_head [noderef] __rcu *buckets @@ net/core/neighbour.c:548:31: sparse: expected void const *ptr net/core/neighbour.c:548:31: sparse: got struct hlist_head [noderef] __rcu *buckets >> net/core/neighbour.c:572:25: sparse: sparse: incompatible types in comparison expression (different address spaces): net/core/neighbour.c:572:25: sparse: struct hlist_node [noderef] __rcu * net/core/neighbour.c:572:25: sparse: struct hlist_node * >> net/core/neighbour.c:669:9: sparse: sparse: cast removes address space '__rcu' of expression >> net/core/neighbour.c:669:9: sparse: sparse: cast removes address space '__rcu' of expression >> net/core/neighbour.c:669:9: sparse: sparse: cast removes address space '__rcu' of expression >> net/core/neighbour.c:669:9: sparse: sparse: cast removes address space '__rcu' of expression >> net/core/neighbour.c:669:9: sparse: sparse: cast removes address space '__rcu' of expression >> net/core/neighbour.c:669:9: sparse: sparse: cast removes address space '__rcu' of expression >> net/core/neighbour.c:669:9: sparse: sparse: cast removes address space '__rcu' of expression >> net/core/neighbour.c:669:9: sparse: sparse: cast removes address space '__rcu' of expression >> net/core/neighbour.c:669:9: sparse: sparse: cast removes address space '__rcu' of expression >> net/core/neighbour.c:669:9: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:688:29: sparse: sparse: incorrect type in argument 1 (different modifiers) @@ expected struct hlist_node *n @@ got struct hlist_node [noderef] * @@ >> net/core/neighbour.c:688:56: sparse: sparse: incorrect type in argument 2 (different address spaces) @@ expected struct hlist_head *h @@ got struct hlist_head [noderef] __rcu * @@ net/core/neighbour.c:948:23: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:971:48: sparse: sparse: incorrect type in argument 1 (different modifiers) @@ expected struct hlist_node *n @@ got struct hlist_node [noderef] * @@ net/core/neighbour.c:2698:17: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:2698:17: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:2698:17: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:2698:17: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:2698:17: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:2698:17: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:2698:17: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:2698:17: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:2698:17: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:2698:17: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:3065:17: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:3065:17: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:3065:17: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:3065:17: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:3065:17: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:3065:17: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:3065:17: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:3065:17: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:3065:17: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:3065:17: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:3086:23: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:3094:48: sparse: sparse: incorrect type in argument 1 (different modifiers) @@ expected struct hlist_node *n @@ got struct hlist_node [noderef] * @@ net/core/neighbour.c:3164:17: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:3164:17: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:3164:17: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:3164:17: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:3164:17: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:3164:17: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:3164:17: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:3164:17: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:3164:17: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:3164:17: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:3203:14: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:3222:30: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:3231:41: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:3231:22: sparse: sparse: cast removes address space '__rcu' of expression net/core/neighbour.c:429:9: sparse: sparse: context imbalance in '__neigh_ifdown' - wrong count at exit >> net/core/neighbour.c:572:25: sparse: sparse: dereference of noderef expression net/core/neighbour.c: note: in included file: >> include/net/neighbour.h:307:38: sparse: sparse: cast removes address space '__rcu' of expression >> include/net/neighbour.h:307:38: sparse: sparse: incompatible types in comparison expression (different address spaces): include/net/neighbour.h:307:38: sparse: struct hlist_node [noderef] __rcu * include/net/neighbour.h:307:38: sparse: struct hlist_node * include/net/neighbour.h:309:38: sparse: sparse: incompatible types in comparison expression (different address spaces): include/net/neighbour.h:309:38: sparse: struct hlist_node [noderef] __rcu * include/net/neighbour.h:309:38: sparse: struct hlist_node * >> include/net/neighbour.h:307:38: sparse: sparse: incompatible types in comparison expression (different address spaces): include/net/neighbour.h:307:38: sparse: struct hlist_node [noderef] __rcu * include/net/neighbour.h:307:38: sparse: struct hlist_node * include/net/neighbour.h:309:38: sparse: sparse: incompatible types in comparison expression (different address spaces): include/net/neighbour.h:309:38: sparse: struct hlist_node [noderef] __rcu * include/net/neighbour.h:309:38: sparse: struct hlist_node * >> include/net/neighbour.h:307:38: sparse: sparse: incompatible types in comparison expression (different address spaces): include/net/neighbour.h:307:38: sparse: struct hlist_node [noderef] __rcu * include/net/neighbour.h:307:38: sparse: struct hlist_node * include/net/neighbour.h:309:38: sparse: sparse: incompatible types in comparison expression (different address spaces): include/net/neighbour.h:309:38: sparse: struct hlist_node [noderef] __rcu * include/net/neighbour.h:309:38: sparse: struct hlist_node * -- net/core/filter.c:1423:39: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected struct sock_filter const *filter @@ got struct sock_filter [noderef] __user *filter @@ net/core/filter.c:1423:39: sparse: expected struct sock_filter const *filter net/core/filter.c:1423:39: sparse: got struct sock_filter [noderef] __user *filter net/core/filter.c:1501:39: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected struct sock_filter const *filter @@ got struct sock_filter [noderef] __user *filter @@ net/core/filter.c:1501:39: sparse: expected struct sock_filter const *filter net/core/filter.c:1501:39: sparse: got struct sock_filter [noderef] __user *filter net/core/filter.c:2340:45: sparse: sparse: incorrect type in argument 2 (different base types) @@ expected restricted __be32 [usertype] daddr @@ got unsigned int [usertype] ipv4_nh @@ net/core/filter.c:2340:45: sparse: expected restricted __be32 [usertype] daddr net/core/filter.c:2340:45: sparse: got unsigned int [usertype] ipv4_nh net/core/filter.c:11048:31: sparse: sparse: symbol 'cg_skb_verifier_ops' was not declared. Should it be static? net/core/filter.c:11054:27: sparse: sparse: symbol 'cg_skb_prog_ops' was not declared. Should it be static? net/core/filter.c:11098:31: sparse: sparse: symbol 'cg_sock_verifier_ops' was not declared. Should it be static? net/core/filter.c:11104:27: sparse: sparse: symbol 'cg_sock_prog_ops' was not declared. Should it be static? net/core/filter.c:11107:31: sparse: sparse: symbol 'cg_sock_addr_verifier_ops' was not declared. Should it be static? net/core/filter.c:11113:27: sparse: sparse: symbol 'cg_sock_addr_prog_ops' was not declared. Should it be static? net/core/filter.c:1943:43: sparse: sparse: incorrect type in argument 2 (different base types) @@ expected restricted __wsum [usertype] diff @@ got unsigned long long [usertype] to @@ net/core/filter.c:1943:43: sparse: expected restricted __wsum [usertype] diff net/core/filter.c:1943:43: sparse: got unsigned long long [usertype] to net/core/filter.c:1946:36: sparse: sparse: incorrect type in argument 2 (different base types) @@ expected restricted __be16 [usertype] old @@ got unsigned long long [usertype] from @@ net/core/filter.c:1946:36: sparse: expected restricted __be16 [usertype] old net/core/filter.c:1946:36: sparse: got unsigned long long [usertype] from net/core/filter.c:1946:42: sparse: sparse: incorrect type in argument 3 (different base types) @@ expected restricted __be16 [usertype] new @@ got unsigned long long [usertype] to @@ net/core/filter.c:1946:42: sparse: expected restricted __be16 [usertype] new net/core/filter.c:1946:42: sparse: got unsigned long long [usertype] to net/core/filter.c:1949:36: sparse: sparse: incorrect type in argument 2 (different base types) @@ expected restricted __be32 [usertype] from @@ got unsigned long long [usertype] from @@ net/core/filter.c:1949:36: sparse: expected restricted __be32 [usertype] from net/core/filter.c:1949:36: sparse: got unsigned long long [usertype] from net/core/filter.c:1949:42: sparse: sparse: incorrect type in argument 3 (different base types) @@ expected restricted __be32 [usertype] to @@ got unsigned long long [usertype] to @@ net/core/filter.c:1949:42: sparse: expected restricted __be32 [usertype] to net/core/filter.c:1949:42: sparse: got unsigned long long [usertype] to net/core/filter.c:1994:59: sparse: sparse: incorrect type in argument 3 (different base types) @@ expected restricted __wsum [usertype] diff @@ got unsigned long long [usertype] to @@ net/core/filter.c:1994:59: sparse: expected restricted __wsum [usertype] diff net/core/filter.c:1994:59: sparse: got unsigned long long [usertype] to net/core/filter.c:1997:52: sparse: sparse: incorrect type in argument 3 (different base types) @@ expected restricted __be16 [usertype] from @@ got unsigned long long [usertype] from @@ net/core/filter.c:1997:52: sparse: expected restricted __be16 [usertype] from net/core/filter.c:1997:52: sparse: got unsigned long long [usertype] from net/core/filter.c:1997:58: sparse: sparse: incorrect type in argument 4 (different base types) @@ expected restricted __be16 [usertype] to @@ got unsigned long long [usertype] to @@ net/core/filter.c:1997:58: sparse: expected restricted __be16 [usertype] to net/core/filter.c:1997:58: sparse: got unsigned long long [usertype] to net/core/filter.c:2000:52: sparse: sparse: incorrect type in argument 3 (different base types) @@ expected restricted __be32 [usertype] from @@ got unsigned long long [usertype] from @@ net/core/filter.c:2000:52: sparse: expected restricted __be32 [usertype] from net/core/filter.c:2000:52: sparse: got unsigned long long [usertype] from net/core/filter.c:2000:58: sparse: sparse: incorrect type in argument 4 (different base types) @@ expected restricted __be32 [usertype] to @@ got unsigned long long [usertype] to @@ net/core/filter.c:2000:58: sparse: expected restricted __be32 [usertype] to net/core/filter.c:2000:58: sparse: got unsigned long long [usertype] to net/core/filter.c:2050:16: sparse: sparse: incorrect type in return expression (different base types) @@ expected unsigned long long @@ got restricted __wsum [assigned] [usertype] ret @@ net/core/filter.c:2050:16: sparse: expected unsigned long long net/core/filter.c:2050:16: sparse: got restricted __wsum [assigned] [usertype] ret net/core/filter.c:2072:35: sparse: sparse: incorrect type in return expression (different base types) @@ expected unsigned long long @@ got restricted __wsum [usertype] csum @@ net/core/filter.c:2072:35: sparse: expected unsigned long long net/core/filter.c:2072:35: sparse: got restricted __wsum [usertype] csum net/core/filter.c: note: in included file (through include/net/dst.h, include/net/sock.h, include/linux/sock_diag.h): >> include/net/neighbour.h:307:38: sparse: sparse: cast removes address space '__rcu' of expression >> include/net/neighbour.h:307:38: sparse: sparse: incompatible types in comparison expression (different address spaces): include/net/neighbour.h:307:38: sparse: struct hlist_node [noderef] __rcu * include/net/neighbour.h:307:38: sparse: struct hlist_node * include/net/neighbour.h:309:38: sparse: sparse: incompatible types in comparison expression (different address spaces): include/net/neighbour.h:309:38: sparse: struct hlist_node [noderef] __rcu * include/net/neighbour.h:309:38: sparse: struct hlist_node * >> include/net/neighbour.h:307:38: sparse: sparse: incompatible types in comparison expression (different address spaces): include/net/neighbour.h:307:38: sparse: struct hlist_node [noderef] __rcu * include/net/neighbour.h:307:38: sparse: struct hlist_node * include/net/neighbour.h:309:38: sparse: sparse: incompatible types in comparison expression (different address spaces): include/net/neighbour.h:309:38: sparse: struct hlist_node [noderef] __rcu * include/net/neighbour.h:309:38: sparse: struct hlist_node * >> include/net/neighbour.h:307:38: sparse: sparse: incompatible types in comparison expression (different address spaces): include/net/neighbour.h:307:38: sparse: struct hlist_node [noderef] __rcu * include/net/neighbour.h:307:38: sparse: struct hlist_node * include/net/neighbour.h:309:38: sparse: sparse: incompatible types in comparison expression (different address spaces): include/net/neighbour.h:309:38: sparse: struct hlist_node [noderef] __rcu * include/net/neighbour.h:309:38: sparse: struct hlist_node * >> include/net/neighbour.h:307:38: sparse: sparse: incompatible types in comparison expression (different address spaces): include/net/neighbour.h:307:38: sparse: struct hlist_node [noderef] __rcu * include/net/neighbour.h:307:38: sparse: struct hlist_node * include/net/neighbour.h:309:38: sparse: sparse: incompatible types in comparison expression (different address spaces): include/net/neighbour.h:309:38: sparse: struct hlist_node [noderef] __rcu * include/net/neighbour.h:309:38: sparse: struct hlist_node * >> include/net/neighbour.h:307:38: sparse: sparse: incompatible types in comparison expression (different address spaces): include/net/neighbour.h:307:38: sparse: struct hlist_node [noderef] __rcu * include/net/neighbour.h:307:38: sparse: struct hlist_node * include/net/neighbour.h:309:38: sparse: sparse: incompatible types in comparison expression (different address spaces): include/net/neighbour.h:309:38: sparse: struct hlist_node [noderef] __rcu * include/net/neighbour.h:309:38: sparse: struct hlist_node * >> include/net/neighbour.h:307:38: sparse: sparse: incompatible types in comparison expression (different address spaces): include/net/neighbour.h:307:38: sparse: struct hlist_node [noderef] __rcu * include/net/neighbour.h:307:38: sparse: struct hlist_node * include/net/neighbour.h:309:38: sparse: sparse: incompatible types in comparison expression (different address spaces): include/net/neighbour.h:309:38: sparse: struct hlist_node [noderef] __rcu * include/net/neighbour.h:309:38: sparse: struct hlist_node * >> include/net/neighbour.h:307:38: sparse: sparse: incompatible types in comparison expression (different address spaces): include/net/neighbour.h:307:38: sparse: struct hlist_node [noderef] __rcu * include/net/neighbour.h:307:38: sparse: struct hlist_node * include/net/neighbour.h:309:38: sparse: sparse: incompatible types in comparison expression (different address spaces): include/net/neighbour.h:309:38: sparse: struct hlist_node [noderef] __rcu * include/net/neighbour.h:309:38: sparse: struct hlist_node * >> include/net/neighbour.h:307:38: sparse: sparse: incompatible types in comparison expression (different address spaces): include/net/neighbour.h:307:38: sparse: struct hlist_node [noderef] __rcu * include/net/neighbour.h:307:38: sparse: struct hlist_node * include/net/neighbour.h:309:38: sparse: sparse: incompatible types in comparison expression (different address spaces): include/net/neighbour.h:309:38: sparse: struct hlist_node [noderef] __rcu * include/net/neighbour.h:309:38: sparse: struct hlist_node * >> include/net/neighbour.h:307:38: sparse: sparse: incompatible types in comparison expression (different address spaces): include/net/neighbour.h:307:38: sparse: struct hlist_node [noderef] __rcu * include/net/neighbour.h:307:38: sparse: struct hlist_node * include/net/neighbour.h:309:38: sparse: sparse: incompatible types in comparison expression (different address spaces): include/net/neighbour.h:309:38: sparse: struct hlist_node [noderef] __rcu * include/net/neighbour.h:309:38: sparse: struct hlist_node * vim +/__rcu +669 net/core/neighbour.c 507 508 static struct neigh_hash_table *neigh_hash_alloc(unsigned int shift) 509 { 510 size_t size = (1 << shift) * sizeof(struct hlist_head); 511 struct neigh_hash_table *ret; 512 struct hlist_head __rcu *buckets; 513 int i; 514 515 ret = kmalloc(sizeof(*ret), GFP_ATOMIC); 516 if (!ret) 517 return NULL; 518 if (size <= PAGE_SIZE) { > 519 buckets = kzalloc(size, GFP_ATOMIC); 520 } else { 521 buckets = (struct hlist_head __rcu *) 522 __get_free_pages(GFP_ATOMIC | __GFP_ZERO, 523 get_order(size)); > 524 kmemleak_alloc(buckets, size, 1, GFP_ATOMIC); 525 } 526 if (!buckets) { 527 kfree(ret); 528 return NULL; 529 } 530 ret->hash_buckets = buckets; 531 ret->hash_shift = shift; 532 for (i = 0; i < NEIGH_NUM_HASH_RND; i++) 533 neigh_get_hash_rnd(&ret->hash_rnd[i]); 534 return ret; 535 } 536 537 static void neigh_hash_free_rcu(struct rcu_head *head) 538 { 539 struct neigh_hash_table *nht = container_of(head, 540 struct neigh_hash_table, 541 rcu); 542 size_t size = (1 << nht->hash_shift) * sizeof(struct hlist_head); 543 struct hlist_head __rcu *buckets = nht->hash_buckets; 544 545 if (size <= PAGE_SIZE) { > 546 kfree(buckets); 547 } else { > 548 kmemleak_free(buckets); 549 free_pages((unsigned long)buckets, get_order(size)); 550 } 551 kfree(nht); 552 } 553 554 static struct neigh_hash_table *neigh_hash_grow(struct neigh_table *tbl, 555 unsigned long new_shift) 556 { 557 unsigned int i, hash; 558 struct neigh_hash_table *new_nht, *old_nht; 559 560 NEIGH_CACHE_STAT_INC(tbl, hash_grows); 561 562 old_nht = rcu_dereference_protected(tbl->nht, 563 lockdep_is_held(&tbl->lock)); 564 new_nht = neigh_hash_alloc(new_shift); 565 if (!new_nht) 566 return old_nht; 567 568 for (i = 0; i < (1 << old_nht->hash_shift); i++) { 569 struct neighbour *n, *next; 570 571 for (n = (struct neighbour *) > 572 rcu_dereference_protected(old_nht->hash_buckets[i].first, 573 lockdep_is_held(&tbl->lock)); 574 n != NULL; 575 n = next) { 576 hash = tbl->hash(n->primary_key, n->dev, 577 new_nht->hash_rnd); 578 579 hash >>= (32 - new_nht->hash_shift); 580 next = (struct neighbour *)hlist_next_rcu(&n->list); 581 hlist_del_rcu(&n->list); 582 hlist_add_head_rcu(&n->list, &new_nht->hash_buckets[hash]); 583 } 584 } 585 586 rcu_assign_pointer(tbl->nht, new_nht); 587 call_rcu(&old_nht->rcu, neigh_hash_free_rcu); 588 return new_nht; 589 } 590 591 struct neighbour *neigh_lookup(struct neigh_table *tbl, const void *pkey, 592 struct net_device *dev) 593 { 594 struct neighbour *n; 595 596 NEIGH_CACHE_STAT_INC(tbl, lookups); 597 598 rcu_read_lock(); 599 n = __neigh_lookup_noref(tbl, pkey, dev); 600 if (n) { 601 if (!refcount_inc_not_zero(&n->refcnt)) 602 n = NULL; 603 NEIGH_CACHE_STAT_INC(tbl, hits); 604 } 605 606 rcu_read_unlock(); 607 return n; 608 } 609 EXPORT_SYMBOL(neigh_lookup); 610 611 static struct neighbour * 612 ___neigh_create(struct neigh_table *tbl, const void *pkey, 613 struct net_device *dev, u32 flags, 614 bool exempt_from_gc, bool want_ref) 615 { 616 u32 hash_val, key_len = tbl->key_len; 617 struct neighbour *n1, *rc, *n; 618 struct neigh_hash_table *nht; 619 int error; 620 621 n = neigh_alloc(tbl, dev, flags, exempt_from_gc); 622 trace_neigh_create(tbl, dev, pkey, n, exempt_from_gc); 623 if (!n) { 624 rc = ERR_PTR(-ENOBUFS); 625 goto out; 626 } 627 628 memcpy(n->primary_key, pkey, key_len); 629 n->dev = dev; 630 netdev_hold(dev, &n->dev_tracker, GFP_ATOMIC); 631 632 /* Protocol specific setup. */ 633 if (tbl->constructor && (error = tbl->constructor(n)) < 0) { 634 rc = ERR_PTR(error); 635 goto out_neigh_release; 636 } 637 638 if (dev->netdev_ops->ndo_neigh_construct) { 639 error = dev->netdev_ops->ndo_neigh_construct(dev, n); 640 if (error < 0) { 641 rc = ERR_PTR(error); 642 goto out_neigh_release; 643 } 644 } 645 646 /* Device specific setup. */ 647 if (n->parms->neigh_setup && 648 (error = n->parms->neigh_setup(n)) < 0) { 649 rc = ERR_PTR(error); 650 goto out_neigh_release; 651 } 652 653 n->confirmed = jiffies - (NEIGH_VAR(n->parms, BASE_REACHABLE_TIME) << 1); 654 655 write_lock_bh(&tbl->lock); 656 nht = rcu_dereference_protected(tbl->nht, 657 lockdep_is_held(&tbl->lock)); 658 659 if (atomic_read(&tbl->entries) > (1 << nht->hash_shift)) 660 nht = neigh_hash_grow(tbl, nht->hash_shift + 1); 661 662 hash_val = tbl->hash(n->primary_key, dev, nht->hash_rnd) >> (32 - nht->hash_shift); 663 664 if (n->parms->dead) { 665 rc = ERR_PTR(-EINVAL); 666 goto out_tbl_unlock; 667 } 668 > 669 hlist_for_each_entry_rcu(n1, 670 &nht->hash_buckets[hash_val], 671 list, 672 lockdep_is_held(&tbl->lock)) { 673 if (dev == n1->dev && !memcmp(n1->primary_key, n->primary_key, key_len)) { 674 if (want_ref) 675 neigh_hold(n1); 676 rc = n1; 677 goto out_tbl_unlock; 678 } 679 } 680 681 n->dead = 0; 682 if (!exempt_from_gc) 683 list_add_tail(&n->gc_list, &n->tbl->gc_list); 684 if (n->flags & NTF_MANAGED) 685 list_add_tail(&n->managed_list, &n->tbl->managed_list); 686 if (want_ref) 687 neigh_hold(n); > 688 hlist_add_head_rcu(&n->list, &nht->hash_buckets[hash_val]); 689 write_unlock_bh(&tbl->lock); 690 neigh_dbg(2, "neigh %p is created\n", n); 691 rc = n; 692 out: 693 return rc; 694 out_tbl_unlock: 695 write_unlock_bh(&tbl->lock); 696 out_neigh_release: 697 if (!exempt_from_gc) 698 atomic_dec(&tbl->gc_entries); 699 neigh_release(n); 700 goto out; 701 } 702
Hey Simon, Thank you for the notes, I'll make sure that Sparse is happy. For some reason I can't get it to accept `hlist_for_each_entry_rcu`, complaining that the cast removes `__rcu`, (even if I add `__rcu` to the `pos` variable definition): > static int neigh_dump_table(struct neigh_table *tbl, struct sk_buff *skb, > struct netlink_callback *cb, > struct neigh_dump_filter *filter) > { > struct net *net = sock_net(skb->sk); > struct neighbour __rcu *n; <snip> Line 2752: > hlist_for_each_entry_rcu(n, &nht->hash_buckets[h], list) { Sparse output: > net/core/neighbour.c:2752:17: sparse: warning: cast removes address space '__rcu' of expression Do you know if this is solveable without reverting to the previous style of iteration? Thank you
diff --git a/include/net/neighbour.h b/include/net/neighbour.h index a44f262a7384..77a4aa53aecb 100644 --- a/include/net/neighbour.h +++ b/include/net/neighbour.h @@ -135,7 +135,7 @@ struct neigh_statistics { #define NEIGH_CACHE_STAT_INC(tbl, field) this_cpu_inc((tbl)->stats->field) struct neighbour { - struct neighbour __rcu *next; + struct hlist_node __rcu list; struct neigh_table *tbl; struct neigh_parms *parms; unsigned long confirmed; @@ -190,7 +190,7 @@ struct pneigh_entry { #define NEIGH_NUM_HASH_RND 4 struct neigh_hash_table { - struct neighbour __rcu **hash_buckets; + struct hlist_head __rcu *hash_buckets; unsigned int hash_shift; __u32 hash_rnd[NEIGH_NUM_HASH_RND]; struct rcu_head rcu; @@ -304,9 +304,9 @@ static inline struct neighbour *___neigh_lookup_noref( u32 hash_val; hash_val = hash(pkey, dev, nht->hash_rnd) >> (32 - nht->hash_shift); - for (n = rcu_dereference(nht->hash_buckets[hash_val]); + for (n = (struct neighbour *)rcu_dereference(nht->hash_buckets[hash_val].first); n != NULL; - n = rcu_dereference(n->next)) { + n = (struct neighbour *)rcu_dereference(n->list.next)) { if (n->dev == dev && key_eq(n, pkey)) return n; } diff --git a/net/core/neighbour.c b/net/core/neighbour.c index 77b819cd995b..5b48ed1fdcf0 100644 --- a/net/core/neighbour.c +++ b/net/core/neighbour.c @@ -37,6 +37,7 @@ #include <linux/string.h> #include <linux/log2.h> #include <linux/inetdevice.h> +#include <linux/rculist.h> #include <net/addrconf.h> #include <trace/events/neigh.h> @@ -205,18 +206,13 @@ static void neigh_update_flags(struct neighbour *neigh, u32 flags, int *notify, } } -static bool neigh_del(struct neighbour *n, struct neighbour __rcu **np, - struct neigh_table *tbl) +static bool neigh_del(struct neighbour *n, struct neigh_table *tbl) { bool retval = false; write_lock(&n->lock); if (refcount_read(&n->refcnt) == 1) { - struct neighbour *neigh; - - neigh = rcu_dereference_protected(n->next, - lockdep_is_held(&tbl->lock)); - rcu_assign_pointer(*np, neigh); + hlist_del_rcu(&n->list); neigh_mark_dead(n); retval = true; } @@ -228,25 +224,7 @@ static bool neigh_del(struct neighbour *n, struct neighbour __rcu **np, bool neigh_remove_one(struct neighbour *ndel, struct neigh_table *tbl) { - struct neigh_hash_table *nht; - void *pkey = ndel->primary_key; - u32 hash_val; - struct neighbour *n; - struct neighbour __rcu **np; - - nht = rcu_dereference_protected(tbl->nht, - lockdep_is_held(&tbl->lock)); - hash_val = tbl->hash(pkey, ndel->dev, nht->hash_rnd); - hash_val = hash_val >> (32 - nht->hash_shift); - - np = &nht->hash_buckets[hash_val]; - while ((n = rcu_dereference_protected(*np, - lockdep_is_held(&tbl->lock)))) { - if (n == ndel) - return neigh_del(n, np, tbl); - np = &n->next; - } - return false; + return neigh_del(ndel, tbl); } static int neigh_forced_gc(struct neigh_table *tbl) @@ -388,21 +366,20 @@ static void neigh_flush_dev(struct neigh_table *tbl, struct net_device *dev, for (i = 0; i < (1 << nht->hash_shift); i++) { struct neighbour *n; - struct neighbour __rcu **np = &nht->hash_buckets[i]; + struct neighbour __rcu **np = + (struct neighbour __rcu **)&nht->hash_buckets[i].first; while ((n = rcu_dereference_protected(*np, lockdep_is_held(&tbl->lock))) != NULL) { if (dev && n->dev != dev) { - np = &n->next; + np = (struct neighbour __rcu **)&n->list.next; continue; } if (skip_perm && n->nud_state & NUD_PERMANENT) { - np = &n->next; + np = (struct neighbour __rcu **)&n->list.next; continue; } - rcu_assign_pointer(*np, - rcu_dereference_protected(n->next, - lockdep_is_held(&tbl->lock))); + hlist_del_rcu(&n->list); write_lock(&n->lock); neigh_del_timer(n); neigh_mark_dead(n); @@ -530,9 +507,9 @@ static void neigh_get_hash_rnd(u32 *x) static struct neigh_hash_table *neigh_hash_alloc(unsigned int shift) { - size_t size = (1 << shift) * sizeof(struct neighbour *); + size_t size = (1 << shift) * sizeof(struct hlist_head); struct neigh_hash_table *ret; - struct neighbour __rcu **buckets; + struct hlist_head __rcu *buckets; int i; ret = kmalloc(sizeof(*ret), GFP_ATOMIC); @@ -541,7 +518,7 @@ static struct neigh_hash_table *neigh_hash_alloc(unsigned int shift) if (size <= PAGE_SIZE) { buckets = kzalloc(size, GFP_ATOMIC); } else { - buckets = (struct neighbour __rcu **) + buckets = (struct hlist_head __rcu *) __get_free_pages(GFP_ATOMIC | __GFP_ZERO, get_order(size)); kmemleak_alloc(buckets, size, 1, GFP_ATOMIC); @@ -562,8 +539,8 @@ static void neigh_hash_free_rcu(struct rcu_head *head) struct neigh_hash_table *nht = container_of(head, struct neigh_hash_table, rcu); - size_t size = (1 << nht->hash_shift) * sizeof(struct neighbour *); - struct neighbour __rcu **buckets = nht->hash_buckets; + size_t size = (1 << nht->hash_shift) * sizeof(struct hlist_head); + struct hlist_head __rcu *buckets = nht->hash_buckets; if (size <= PAGE_SIZE) { kfree(buckets); @@ -591,22 +568,18 @@ static struct neigh_hash_table *neigh_hash_grow(struct neigh_table *tbl, for (i = 0; i < (1 << old_nht->hash_shift); i++) { struct neighbour *n, *next; - for (n = rcu_dereference_protected(old_nht->hash_buckets[i], - lockdep_is_held(&tbl->lock)); + for (n = (struct neighbour *) + rcu_dereference_protected(old_nht->hash_buckets[i].first, + lockdep_is_held(&tbl->lock)); n != NULL; n = next) { hash = tbl->hash(n->primary_key, n->dev, new_nht->hash_rnd); hash >>= (32 - new_nht->hash_shift); - next = rcu_dereference_protected(n->next, - lockdep_is_held(&tbl->lock)); - - rcu_assign_pointer(n->next, - rcu_dereference_protected( - new_nht->hash_buckets[hash], - lockdep_is_held(&tbl->lock))); - rcu_assign_pointer(new_nht->hash_buckets[hash], n); + next = (struct neighbour *)hlist_next_rcu(&n->list); + hlist_del_rcu(&n->list); + hlist_add_head_rcu(&n->list, &new_nht->hash_buckets[hash]); } } @@ -693,11 +666,10 @@ ___neigh_create(struct neigh_table *tbl, const void *pkey, goto out_tbl_unlock; } - for (n1 = rcu_dereference_protected(nht->hash_buckets[hash_val], - lockdep_is_held(&tbl->lock)); - n1 != NULL; - n1 = rcu_dereference_protected(n1->next, - lockdep_is_held(&tbl->lock))) { + hlist_for_each_entry_rcu(n1, + &nht->hash_buckets[hash_val], + list, + lockdep_is_held(&tbl->lock)) { if (dev == n1->dev && !memcmp(n1->primary_key, n->primary_key, key_len)) { if (want_ref) neigh_hold(n1); @@ -713,10 +685,7 @@ ___neigh_create(struct neigh_table *tbl, const void *pkey, list_add_tail(&n->managed_list, &n->tbl->managed_list); if (want_ref) neigh_hold(n); - rcu_assign_pointer(n->next, - rcu_dereference_protected(nht->hash_buckets[hash_val], - lockdep_is_held(&tbl->lock))); - rcu_assign_pointer(nht->hash_buckets[hash_val], n); + hlist_add_head_rcu(&n->list, &nht->hash_buckets[hash_val]); write_unlock_bh(&tbl->lock); neigh_dbg(2, "neigh %p is created\n", n); rc = n; @@ -976,7 +945,7 @@ static void neigh_periodic_work(struct work_struct *work) goto out; for (i = 0 ; i < (1 << nht->hash_shift); i++) { - np = &nht->hash_buckets[i]; + np = (struct neighbour __rcu **)&nht->hash_buckets[i].first; while ((n = rcu_dereference_protected(*np, lockdep_is_held(&tbl->lock))) != NULL) { @@ -999,9 +968,7 @@ static void neigh_periodic_work(struct work_struct *work) (state == NUD_FAILED || !time_in_range_open(jiffies, n->used, n->used + NEIGH_VAR(n->parms, GC_STALETIME)))) { - rcu_assign_pointer(*np, - rcu_dereference_protected(n->next, - lockdep_is_held(&tbl->lock))); + hlist_del_rcu(&n->list); neigh_mark_dead(n); write_unlock(&n->lock); neigh_cleanup_and_release(n); @@ -1010,7 +977,7 @@ static void neigh_periodic_work(struct work_struct *work) write_unlock(&n->lock); next_elt: - np = &n->next; + np = (struct neighbour __rcu **)&n->list.next; } /* * It's fine to release lock here, even if hash table @@ -2728,9 +2695,7 @@ static int neigh_dump_table(struct neigh_table *tbl, struct sk_buff *skb, for (h = s_h; h < (1 << nht->hash_shift); h++) { if (h > s_h) s_idx = 0; - for (n = rcu_dereference(nht->hash_buckets[h]), idx = 0; - n != NULL; - n = rcu_dereference(n->next)) { + hlist_for_each_entry_rcu(n, &nht->hash_buckets[h], list) { if (idx < s_idx || !net_eq(dev_net(n->dev), net)) goto next; if (neigh_ifindex_filtered(n->dev, filter->dev_idx) || @@ -3097,9 +3062,7 @@ void neigh_for_each(struct neigh_table *tbl, void (*cb)(struct neighbour *, void for (chain = 0; chain < (1 << nht->hash_shift); chain++) { struct neighbour *n; - for (n = rcu_dereference(nht->hash_buckets[chain]); - n != NULL; - n = rcu_dereference(n->next)) + hlist_for_each_entry_rcu(n, &nht->hash_buckets[chain], list) cb(n, cookie); } read_unlock_bh(&tbl->lock); @@ -3120,7 +3083,7 @@ void __neigh_for_each_release(struct neigh_table *tbl, struct neighbour *n; struct neighbour __rcu **np; - np = &nht->hash_buckets[chain]; + np = (struct neighbour __rcu **)&nht->hash_buckets[chain].first; while ((n = rcu_dereference_protected(*np, lockdep_is_held(&tbl->lock))) != NULL) { int release; @@ -3128,12 +3091,10 @@ void __neigh_for_each_release(struct neigh_table *tbl, write_lock(&n->lock); release = cb(n); if (release) { - rcu_assign_pointer(*np, - rcu_dereference_protected(n->next, - lockdep_is_held(&tbl->lock))); + hlist_del_rcu(&n->list); neigh_mark_dead(n); } else - np = &n->next; + np = (struct neighbour __rcu **)&n->list.next; write_unlock(&n->lock); if (release) neigh_cleanup_and_release(n); @@ -3200,25 +3161,21 @@ static struct neighbour *neigh_get_first(struct seq_file *seq) state->flags &= ~NEIGH_SEQ_IS_PNEIGH; for (bucket = 0; bucket < (1 << nht->hash_shift); bucket++) { - n = rcu_dereference(nht->hash_buckets[bucket]); - - while (n) { + hlist_for_each_entry_rcu(n, &nht->hash_buckets[bucket], list) { if (!net_eq(dev_net(n->dev), net)) - goto next; + continue; if (state->neigh_sub_iter) { loff_t fakep = 0; void *v; v = state->neigh_sub_iter(state, n, &fakep); if (!v) - goto next; + continue; } if (!(state->flags & NEIGH_SEQ_SKIP_NOARP)) break; if (READ_ONCE(n->nud_state) & ~NUD_NOARP) break; -next: - n = rcu_dereference(n->next); } if (n) @@ -3242,7 +3199,8 @@ static struct neighbour *neigh_get_next(struct seq_file *seq, if (v) return n; } - n = rcu_dereference(n->next); + + n = (struct neighbour *)hlist_next_rcu(&n->list); while (1) { while (n) { @@ -3260,7 +3218,8 @@ static struct neighbour *neigh_get_next(struct seq_file *seq, if (READ_ONCE(n->nud_state) & ~NUD_NOARP) break; next: - n = rcu_dereference(n->next); + + n = (struct neighbour *)hlist_next_rcu(&n->list); } if (n) @@ -3269,7 +3228,7 @@ static struct neighbour *neigh_get_next(struct seq_file *seq, if (++state->bucket >= (1 << nht->hash_shift)) break; - n = rcu_dereference(nht->hash_buckets[state->bucket]); + n = (struct neighbour *)hlist_first_rcu(&nht->hash_buckets[state->bucket]); } if (n && pos)
Use doubly-linked instead of singly-linked list when linking neighbours, so that it is possible to remove neighbours without traversing the entire table. Signed-off-by: Gilad Naaman <gnaaman@drivenets.com> --- include/net/neighbour.h | 8 +-- net/core/neighbour.c | 123 ++++++++++++++-------------------------- 2 files changed, 45 insertions(+), 86 deletions(-)