xref: /linux/include/net/proto_memory.h (revision 6dfafbd0299a60bfb5d5e277fdf100037c7ded07)
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 #ifndef _PROTO_MEMORY_H
3 #define _PROTO_MEMORY_H
4 
5 #include <net/sock.h>
6 #include <net/hotdata.h>
7 
8 /* 1 MB per cpu, in page units */
9 #define SK_MEMORY_PCPU_RESERVE (1 << (20 - PAGE_SHIFT))
10 
11 static inline bool sk_has_memory_pressure(const struct sock *sk)
12 {
13 	return sk->sk_prot->memory_pressure != NULL;
14 }
15 
16 static inline bool
17 proto_memory_pressure(const struct proto *prot)
18 {
19 	if (!prot->memory_pressure)
20 		return false;
21 	return !!READ_ONCE(*prot->memory_pressure);
22 }
23 
24 static inline bool sk_under_global_memory_pressure(const struct sock *sk)
25 {
26 	return proto_memory_pressure(sk->sk_prot);
27 }
28 
29 static inline bool sk_under_memory_pressure(const struct sock *sk)
30 {
31 	if (!sk->sk_prot->memory_pressure)
32 		return false;
33 
34 	if (mem_cgroup_sk_enabled(sk) &&
35 	    mem_cgroup_sk_under_memory_pressure(sk))
36 		return true;
37 
38 	if (sk->sk_bypass_prot_mem)
39 		return false;
40 
41 	return !!READ_ONCE(*sk->sk_prot->memory_pressure);
42 }
43 
44 static inline long
45 proto_memory_allocated(const struct proto *prot)
46 {
47 	return max(0L, atomic_long_read(prot->memory_allocated));
48 }
49 
50 static inline long
51 sk_memory_allocated(const struct sock *sk)
52 {
53 	return proto_memory_allocated(sk->sk_prot);
54 }
55 
56 static inline void proto_memory_pcpu_drain(struct proto *proto)
57 {
58 	int val = this_cpu_xchg(*proto->per_cpu_fw_alloc, 0);
59 
60 	if (val)
61 		atomic_long_add(val, proto->memory_allocated);
62 }
63 
64 static inline void
65 sk_memory_allocated_add(const struct sock *sk, int val)
66 {
67 	struct proto *proto = sk->sk_prot;
68 
69 	val = this_cpu_add_return(*proto->per_cpu_fw_alloc, val);
70 
71 	if (unlikely(val >= READ_ONCE(net_hotdata.sysctl_mem_pcpu_rsv)))
72 		proto_memory_pcpu_drain(proto);
73 }
74 
75 static inline void
76 sk_memory_allocated_sub(const struct sock *sk, int val)
77 {
78 	struct proto *proto = sk->sk_prot;
79 
80 	val = this_cpu_sub_return(*proto->per_cpu_fw_alloc, val);
81 
82 	if (unlikely(val <= -READ_ONCE(net_hotdata.sysctl_mem_pcpu_rsv)))
83 		proto_memory_pcpu_drain(proto);
84 }
85 
86 #endif /* _PROTO_MEMORY_H */
87