include/net/hotdata.h

Source file repositories/reference/linux-study-clean/include/net/hotdata.h

File Facts

System: Linux kernel
Corpus path: include/net/hotdata.h
Extension: .h
Size: 1873 bytes
Lines: 66
Domain: Networking Core
Bucket: Sockets, Protocols, Packet Path, And Network Policy
Inferred role: Networking Core: implementation source
Status: source implementation candidate

Why This File Exists

Networking stack implementation surface: socket APIs, protocol dispatch, packet flow, routing, filtering, and network namespaces.

Networking stack implementation surface: socket APIs, protocol dispatch, packet flow, routing, filtering, and network namespaces.
Uses kernel synchronization; read lock ordering, sleepability, and interrupt context assumptions before translating.
Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.

Dependency Surface

linux/llist.h
linux/types.h
linux/netdevice.h
net/protocol.h
net/rps-types.h

Detected Declarations

struct skb_defer_node
struct net_hotdata

Annotated Snippet

struct skb_defer_node {
	struct llist_head	defer_list;
	atomic_long_t		defer_count;
} ____cacheline_aligned_in_smp;

/* Read mostly data used in network fast paths. */
struct net_hotdata {
#if IS_ENABLED(CONFIG_INET)
	struct packet_offload	ip_packet_offload;
	struct net_offload	tcpv4_offload;
	struct net_protocol	tcp_protocol;
	struct net_offload 	udpv4_offload;
	struct net_protocol	udp_protocol;
	struct packet_offload	ipv6_packet_offload;
	struct net_offload	tcpv6_offload;
#if IS_ENABLED(CONFIG_IPV6)
	struct inet6_protocol	tcpv6_protocol;
	struct inet6_protocol	udpv6_protocol;
#endif
	struct net_offload	udpv6_offload;
#endif
	struct list_head	offload_base;
	struct kmem_cache	*skbuff_cache;
	struct kmem_cache	*skbuff_fclone_cache;
	struct kmem_cache	*skb_small_head_cache;
#ifdef CONFIG_RPS
	rps_tag_ptr		rps_sock_flow_table;
	u32			rps_cpu_mask;
#endif
	struct skb_defer_node __percpu *skb_defer_nodes;
	int			gro_normal_batch;
	int			netdev_budget;
	int			netdev_budget_usecs;
	int			tstamp_prequeue;
	int			max_backlog;
	int			qdisc_max_burst;
	int			dev_tx_weight;
	int			dev_rx_weight;
	int			sysctl_max_skb_frags;
	int			sysctl_skb_defer_max;
	int			sysctl_mem_pcpu_rsv;
};

#define inet_ehash_secret	net_hotdata.tcp_protocol.secret
#define udp_ehash_secret	net_hotdata.udp_protocol.secret
#define inet6_ehash_secret	net_hotdata.tcpv6_protocol.secret
#define tcp_ipv6_hash_secret	net_hotdata.tcpv6_offload.secret
#define udp6_ehash_secret	net_hotdata.udpv6_protocol.secret
#define udp_ipv6_hash_secret	net_hotdata.udpv6_offload.secret

extern struct net_hotdata net_hotdata;

#endif /* _NET_HOTDATA_H */

Annotation

Immediate include surface: `linux/llist.h`, `linux/types.h`, `linux/netdevice.h`, `net/protocol.h`, `net/rps-types.h`.
Detected declarations: `struct skb_defer_node`, `struct net_hotdata`.
Atlas domain: Networking Core / Sockets, Protocols, Packet Path, And Network Policy.
Implementation status: source implementation candidate.
Synchronization appears in or near this file; preserve lock ordering, sleepability, and interrupt-context constraints.

Implementation Notes

This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.