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author | Ido Schimmel <idosch@OSS.NVIDIA.COM> | 2021-05-17 21:15:18 +0300 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2021-05-18 13:27:32 -0700 |
commit | ce5c9c20d364f156c885efed8c71fca2945db00f (patch) | |
tree | bb4858afb789ab04d7330dc3bff07f999814bbff | |
parent | 2e68ea92684181412b73979baf1af7d04619c52c (diff) | |
download | linux-ce5c9c20d364f156c885efed8c71fca2945db00f.tar.bz2 |
ipv4: Add a sysctl to control multipath hash fields
A subsequent patch will add a new multipath hash policy where the packet
fields used for multipath hash calculation are determined by user space.
This patch adds a sysctl that allows user space to set these fields.
The packet fields are represented using a bitmask and are common between
IPv4 and IPv6 to allow user space to use the same numbering across both
protocols. For example, to hash based on standard 5-tuple:
# sysctl -w net.ipv4.fib_multipath_hash_fields=0x0037
net.ipv4.fib_multipath_hash_fields = 0x0037
The kernel rejects unknown fields, for example:
# sysctl -w net.ipv4.fib_multipath_hash_fields=0x1000
sysctl: setting key "net.ipv4.fib_multipath_hash_fields": Invalid argument
More fields can be added in the future, if needed.
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
-rw-r--r-- | Documentation/networking/ip-sysctl.rst | 27 | ||||
-rw-r--r-- | include/net/ip_fib.h | 43 | ||||
-rw-r--r-- | include/net/netns/ipv4.h | 1 | ||||
-rw-r--r-- | net/ipv4/fib_frontend.c | 6 | ||||
-rw-r--r-- | net/ipv4/sysctl_net_ipv4.c | 12 |
5 files changed, 89 insertions, 0 deletions
diff --git a/Documentation/networking/ip-sysctl.rst b/Documentation/networking/ip-sysctl.rst index c2ecc9894fd0..47494798d03b 100644 --- a/Documentation/networking/ip-sysctl.rst +++ b/Documentation/networking/ip-sysctl.rst @@ -100,6 +100,33 @@ fib_multipath_hash_policy - INTEGER - 1 - Layer 4 - 2 - Layer 3 or inner Layer 3 if present +fib_multipath_hash_fields - UNSIGNED INTEGER + When fib_multipath_hash_policy is set to 3 (custom multipath hash), the + fields used for multipath hash calculation are determined by this + sysctl. + + This value is a bitmask which enables various fields for multipath hash + calculation. + + Possible fields are: + + ====== ============================ + 0x0001 Source IP address + 0x0002 Destination IP address + 0x0004 IP protocol + 0x0008 Unused (Flow Label) + 0x0010 Source port + 0x0020 Destination port + 0x0040 Inner source IP address + 0x0080 Inner destination IP address + 0x0100 Inner IP protocol + 0x0200 Inner Flow Label + 0x0400 Inner source port + 0x0800 Inner destination port + ====== ============================ + + Default: 0x0007 (source IP, destination IP and IP protocol) + fib_sync_mem - UNSIGNED INTEGER Amount of dirty memory from fib entries that can be backlogged before synchronize_rcu is forced. diff --git a/include/net/ip_fib.h b/include/net/ip_fib.h index a914f33f3ed5..3ab2563b1a23 100644 --- a/include/net/ip_fib.h +++ b/include/net/ip_fib.h @@ -466,6 +466,49 @@ int fib_sync_up(struct net_device *dev, unsigned char nh_flags); void fib_sync_mtu(struct net_device *dev, u32 orig_mtu); void fib_nhc_update_mtu(struct fib_nh_common *nhc, u32 new, u32 orig); +/* Fields used for sysctl_fib_multipath_hash_fields. + * Common to IPv4 and IPv6. + * + * Add new fields at the end. This is user API. + */ +#define FIB_MULTIPATH_HASH_FIELD_SRC_IP BIT(0) +#define FIB_MULTIPATH_HASH_FIELD_DST_IP BIT(1) +#define FIB_MULTIPATH_HASH_FIELD_IP_PROTO BIT(2) +#define FIB_MULTIPATH_HASH_FIELD_FLOWLABEL BIT(3) +#define FIB_MULTIPATH_HASH_FIELD_SRC_PORT BIT(4) +#define FIB_MULTIPATH_HASH_FIELD_DST_PORT BIT(5) +#define FIB_MULTIPATH_HASH_FIELD_INNER_SRC_IP BIT(6) +#define FIB_MULTIPATH_HASH_FIELD_INNER_DST_IP BIT(7) +#define FIB_MULTIPATH_HASH_FIELD_INNER_IP_PROTO BIT(8) +#define FIB_MULTIPATH_HASH_FIELD_INNER_FLOWLABEL BIT(9) +#define FIB_MULTIPATH_HASH_FIELD_INNER_SRC_PORT BIT(10) +#define FIB_MULTIPATH_HASH_FIELD_INNER_DST_PORT BIT(11) + +#define FIB_MULTIPATH_HASH_FIELD_OUTER_MASK \ + (FIB_MULTIPATH_HASH_FIELD_SRC_IP | \ + FIB_MULTIPATH_HASH_FIELD_DST_IP | \ + FIB_MULTIPATH_HASH_FIELD_IP_PROTO | \ + FIB_MULTIPATH_HASH_FIELD_FLOWLABEL | \ + FIB_MULTIPATH_HASH_FIELD_SRC_PORT | \ + FIB_MULTIPATH_HASH_FIELD_DST_PORT) + +#define FIB_MULTIPATH_HASH_FIELD_INNER_MASK \ + (FIB_MULTIPATH_HASH_FIELD_INNER_SRC_IP | \ + FIB_MULTIPATH_HASH_FIELD_INNER_DST_IP | \ + FIB_MULTIPATH_HASH_FIELD_INNER_IP_PROTO | \ + FIB_MULTIPATH_HASH_FIELD_INNER_FLOWLABEL | \ + FIB_MULTIPATH_HASH_FIELD_INNER_SRC_PORT | \ + FIB_MULTIPATH_HASH_FIELD_INNER_DST_PORT) + +#define FIB_MULTIPATH_HASH_FIELD_ALL_MASK \ + (FIB_MULTIPATH_HASH_FIELD_OUTER_MASK | \ + FIB_MULTIPATH_HASH_FIELD_INNER_MASK) + +#define FIB_MULTIPATH_HASH_FIELD_DEFAULT_MASK \ + (FIB_MULTIPATH_HASH_FIELD_SRC_IP | \ + FIB_MULTIPATH_HASH_FIELD_DST_IP | \ + FIB_MULTIPATH_HASH_FIELD_IP_PROTO) + #ifdef CONFIG_IP_ROUTE_MULTIPATH int fib_multipath_hash(const struct net *net, const struct flowi4 *fl4, const struct sk_buff *skb, struct flow_keys *flkeys); diff --git a/include/net/netns/ipv4.h b/include/net/netns/ipv4.h index f6af8d96d3c6..746c80cd4257 100644 --- a/include/net/netns/ipv4.h +++ b/include/net/netns/ipv4.h @@ -210,6 +210,7 @@ struct netns_ipv4 { #endif #endif #ifdef CONFIG_IP_ROUTE_MULTIPATH + u32 sysctl_fib_multipath_hash_fields; u8 sysctl_fib_multipath_use_neigh; u8 sysctl_fib_multipath_hash_policy; #endif diff --git a/net/ipv4/fib_frontend.c b/net/ipv4/fib_frontend.c index bfb345c88271..af8814a11378 100644 --- a/net/ipv4/fib_frontend.c +++ b/net/ipv4/fib_frontend.c @@ -1514,6 +1514,12 @@ static int __net_init ip_fib_net_init(struct net *net) if (err) return err; +#ifdef CONFIG_IP_ROUTE_MULTIPATH + /* Default to 3-tuple */ + net->ipv4.sysctl_fib_multipath_hash_fields = + FIB_MULTIPATH_HASH_FIELD_DEFAULT_MASK; +#endif + /* Avoid false sharing : Use at least a full cache line */ size = max_t(size_t, size, L1_CACHE_BYTES); diff --git a/net/ipv4/sysctl_net_ipv4.c b/net/ipv4/sysctl_net_ipv4.c index a62934b9f15a..45bab3733621 100644 --- a/net/ipv4/sysctl_net_ipv4.c +++ b/net/ipv4/sysctl_net_ipv4.c @@ -19,6 +19,7 @@ #include <net/snmp.h> #include <net/icmp.h> #include <net/ip.h> +#include <net/ip_fib.h> #include <net/route.h> #include <net/tcp.h> #include <net/udp.h> @@ -48,6 +49,8 @@ static int ip_ping_group_range_min[] = { 0, 0 }; static int ip_ping_group_range_max[] = { GID_T_MAX, GID_T_MAX }; static u32 u32_max_div_HZ = UINT_MAX / HZ; static int one_day_secs = 24 * 3600; +static u32 fib_multipath_hash_fields_all_mask __maybe_unused = + FIB_MULTIPATH_HASH_FIELD_ALL_MASK; /* obsolete */ static int sysctl_tcp_low_latency __read_mostly; @@ -1052,6 +1055,15 @@ static struct ctl_table ipv4_net_table[] = { .extra1 = SYSCTL_ZERO, .extra2 = &two, }, + { + .procname = "fib_multipath_hash_fields", + .data = &init_net.ipv4.sysctl_fib_multipath_hash_fields, + .maxlen = sizeof(u32), + .mode = 0644, + .proc_handler = proc_douintvec_minmax, + .extra1 = SYSCTL_ONE, + .extra2 = &fib_multipath_hash_fields_all_mask, + }, #endif { .procname = "ip_unprivileged_port_start", |