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632ca50f2c
A busy-wait loop is used to implement waiting for bits to be copied from the skb to the kernel buffer before retiring a block. This is a problem on PREEMPT_RT because the copying task could be preempted by the busy-waiting task and thus live lock in the busy-wait loop. Replace the busy-wait logic with an rwlock_t. This provides lockdep coverage and makes the code RT ready. Signed-off-by: John Ogness <john.ogness@linutronix.de> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
147 lines
3.3 KiB
C
147 lines
3.3 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
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#ifndef __PACKET_INTERNAL_H__
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#define __PACKET_INTERNAL_H__
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#include <linux/refcount.h>
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struct packet_mclist {
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struct packet_mclist *next;
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int ifindex;
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int count;
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unsigned short type;
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unsigned short alen;
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unsigned char addr[MAX_ADDR_LEN];
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};
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/* kbdq - kernel block descriptor queue */
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struct tpacket_kbdq_core {
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struct pgv *pkbdq;
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unsigned int feature_req_word;
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unsigned int hdrlen;
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unsigned char reset_pending_on_curr_blk;
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unsigned char delete_blk_timer;
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unsigned short kactive_blk_num;
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unsigned short blk_sizeof_priv;
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/* last_kactive_blk_num:
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* trick to see if user-space has caught up
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* in order to avoid refreshing timer when every single pkt arrives.
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*/
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unsigned short last_kactive_blk_num;
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char *pkblk_start;
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char *pkblk_end;
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int kblk_size;
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unsigned int max_frame_len;
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unsigned int knum_blocks;
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uint64_t knxt_seq_num;
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char *prev;
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char *nxt_offset;
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struct sk_buff *skb;
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rwlock_t blk_fill_in_prog_lock;
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/* Default is set to 8ms */
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#define DEFAULT_PRB_RETIRE_TOV (8)
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unsigned short retire_blk_tov;
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unsigned short version;
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unsigned long tov_in_jiffies;
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/* timer to retire an outstanding block */
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struct timer_list retire_blk_timer;
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};
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struct pgv {
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char *buffer;
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};
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struct packet_ring_buffer {
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struct pgv *pg_vec;
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unsigned int head;
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unsigned int frames_per_block;
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unsigned int frame_size;
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unsigned int frame_max;
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unsigned int pg_vec_order;
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unsigned int pg_vec_pages;
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unsigned int pg_vec_len;
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unsigned int __percpu *pending_refcnt;
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union {
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unsigned long *rx_owner_map;
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struct tpacket_kbdq_core prb_bdqc;
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};
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};
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extern struct mutex fanout_mutex;
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#define PACKET_FANOUT_MAX 256
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struct packet_fanout {
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possible_net_t net;
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unsigned int num_members;
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u16 id;
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u8 type;
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u8 flags;
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union {
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atomic_t rr_cur;
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struct bpf_prog __rcu *bpf_prog;
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};
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struct list_head list;
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struct sock *arr[PACKET_FANOUT_MAX];
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spinlock_t lock;
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refcount_t sk_ref;
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struct packet_type prot_hook ____cacheline_aligned_in_smp;
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};
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struct packet_rollover {
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int sock;
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atomic_long_t num;
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atomic_long_t num_huge;
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atomic_long_t num_failed;
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#define ROLLOVER_HLEN (L1_CACHE_BYTES / sizeof(u32))
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u32 history[ROLLOVER_HLEN] ____cacheline_aligned;
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} ____cacheline_aligned_in_smp;
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struct packet_sock {
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/* struct sock has to be the first member of packet_sock */
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struct sock sk;
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struct packet_fanout *fanout;
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union tpacket_stats_u stats;
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struct packet_ring_buffer rx_ring;
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struct packet_ring_buffer tx_ring;
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int copy_thresh;
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spinlock_t bind_lock;
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struct mutex pg_vec_lock;
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unsigned int running; /* bind_lock must be held */
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unsigned int auxdata:1, /* writer must hold sock lock */
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origdev:1,
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has_vnet_hdr:1,
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tp_loss:1,
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tp_tx_has_off:1;
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int pressure;
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int ifindex; /* bound device */
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__be16 num;
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struct packet_rollover *rollover;
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struct packet_mclist *mclist;
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atomic_t mapped;
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enum tpacket_versions tp_version;
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unsigned int tp_hdrlen;
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unsigned int tp_reserve;
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unsigned int tp_tstamp;
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struct completion skb_completion;
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struct net_device __rcu *cached_dev;
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int (*xmit)(struct sk_buff *skb);
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struct packet_type prot_hook ____cacheline_aligned_in_smp;
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atomic_t tp_drops ____cacheline_aligned_in_smp;
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};
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static struct packet_sock *pkt_sk(struct sock *sk)
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{
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return (struct packet_sock *)sk;
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}
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#endif
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