tools/testing/selftests/bpf/progs/bpf_iter_tcp6.c
Source file repositories/reference/linux-study-clean/tools/testing/selftests/bpf/progs/bpf_iter_tcp6.c
File Facts
- System
- Linux kernel
- Corpus path
tools/testing/selftests/bpf/progs/bpf_iter_tcp6.c- Extension
.c- Size
- 6889 bytes
- Lines
- 250
- Domain
- Support Tooling And Documentation
- Bucket
- tools
- Inferred role
- Support Tooling And Documentation: implementation source
- Status
- source implementation candidate
Why This File Exists
Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.
- Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.
- Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.
Dependency Surface
vmlinux.hbpf_tracing_net.hbpf/bpf_helpers.hbpf/bpf_endian.h
Detected Declarations
function hlist_unhashed_locklessfunction timer_pendingfunction jiffies_to_clock_tfunction jiffies_delta_to_clock_tfunction sock_i_inofunction inet_csk_in_pingpong_modefunction tcp_in_initial_slowstartfunction dump_tcp6_sockfunction dump_tw_sockfunction dump_req_sockfunction dump_tcp6
Annotated Snippet
// SPDX-License-Identifier: GPL-2.0
/* Copyright (c) 2020 Facebook */
#include <vmlinux.h>
#include "bpf_tracing_net.h"
#include <bpf/bpf_helpers.h>
#include <bpf/bpf_endian.h>
char _license[] SEC("license") = "GPL";
static int hlist_unhashed_lockless(const struct hlist_node *h)
{
return !(h->pprev);
}
static int timer_pending(const struct timer_list * timer)
{
return !hlist_unhashed_lockless(&timer->entry);
}
extern unsigned CONFIG_HZ __kconfig;
#define USER_HZ 100
#define NSEC_PER_SEC 1000000000ULL
static clock_t jiffies_to_clock_t(unsigned long x)
{
/* The implementation here tailored to a particular
* setting of USER_HZ.
*/
u64 tick_nsec = (NSEC_PER_SEC + CONFIG_HZ/2) / CONFIG_HZ;
u64 user_hz_nsec = NSEC_PER_SEC / USER_HZ;
if ((tick_nsec % user_hz_nsec) == 0) {
if (CONFIG_HZ < USER_HZ)
return x * (USER_HZ / CONFIG_HZ);
else
return x / (CONFIG_HZ / USER_HZ);
}
return x * tick_nsec/user_hz_nsec;
}
static clock_t jiffies_delta_to_clock_t(long delta)
{
if (delta <= 0)
return 0;
return jiffies_to_clock_t(delta);
}
static long sock_i_ino(const struct sock *sk)
{
const struct socket *sk_socket = sk->sk_socket;
const struct inode *inode;
unsigned long ino;
if (!sk_socket)
return 0;
inode = &container_of(sk_socket, struct socket_alloc, socket)->vfs_inode;
bpf_probe_read_kernel(&ino, sizeof(ino), &inode->i_ino);
return ino;
}
static bool
inet_csk_in_pingpong_mode(const struct inet_connection_sock *icsk)
{
return icsk->icsk_ack.pingpong >= TCP_PINGPONG_THRESH;
}
static bool tcp_in_initial_slowstart(const struct tcp_sock *tcp)
{
return tcp->snd_ssthresh >= TCP_INFINITE_SSTHRESH;
}
static int dump_tcp6_sock(struct seq_file *seq, struct tcp6_sock *tp,
uid_t uid, __u32 seq_num)
{
const struct inet_connection_sock *icsk;
const struct fastopen_queue *fastopenq;
const struct in6_addr *dest, *src;
const struct inet_sock *inet;
unsigned long timer_expires;
const struct sock *sp;
__u16 destp, srcp;
int timer_active;
int rx_queue;
int state;
icsk = &tp->tcp.inet_conn;
inet = &icsk->icsk_inet;
sp = &inet->sk;
Annotation
- Immediate include surface: `vmlinux.h`, `bpf_tracing_net.h`, `bpf/bpf_helpers.h`, `bpf/bpf_endian.h`.
- Detected declarations: `function hlist_unhashed_lockless`, `function timer_pending`, `function jiffies_to_clock_t`, `function jiffies_delta_to_clock_t`, `function sock_i_ino`, `function inet_csk_in_pingpong_mode`, `function tcp_in_initial_slowstart`, `function dump_tcp6_sock`, `function dump_tw_sock`, `function dump_req_sock`.
- Atlas domain: Support Tooling And Documentation / tools.
- Implementation status: source implementation candidate.
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.