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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-19 10:09:22 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-19 10:09:22 -0700
commitf4cdf7ca9a1fdcca413157df19753f388a5a224e (patch)
tree60a31895b2446cd7fa27514e8c2843534a0de0da /include/net/rps.h
downloadlinux-stable-f4cdf7ca9a1fdcca413157df19753f388a5a224e.tar.gz
linux-stable-f4cdf7ca9a1fdcca413157df19753f388a5a224e.zip
Merge tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-mediagrafted
Pull media updates from Mauro Carvalho Chehab: - v4l2-core: added ISP statistics support and per-block validation - v4l2-core: Allow unknown HDR10 white point and luminance - New camera sensors: Sony IMX678 and IMX471m, Himax HM1092 IR sensor - New codec: Milos: VPU v2.0 codec support - isp driver: gained support for Dreamchip RPPX1 ISP framework - vsp1 driver: gained support for RZ/T2H and RZ/N2H - Novalake driver: gained CVS support for new NVL hardware - dvb-core: fix feed leak on failed DMX_ADD_PID - several driver fixes, cleanups and minor improvements * tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (308 commits) media: ipu-bridge: check all DMI entries when overriding sensor rotation media: v4l2-async: avoid deleting unlinked ASC entry on link error media: rzg2l-cru: Align bytesperline to hardware DMA stride requirement media: intel/ipu6: fix async notifier cleanup leak on parse error media: staging/ipu7: fix async notifier UAF on probe error path media: amd: isp4: fix self-deadlock in isp4sd_pwron_and_init() error path media: amd: isp4: release partial allocations in isp4if_alloc_fw_gpumem() media: rcar-isp: Fix VSPX reference leaks media: rcar-isp: Release ISPCORE resources media: i2c: imx415: Release runtime PM reference on VBLANK error media: i2c: imx415: Return test pattern write errors media: renesas: vsp1: Declare index variables in for loop statement media: renesas: vsp1: Make reset control optional to support platforms without a reset line media: dt-bindings: media: renesas,vsp1: Document RZ/T2H and RZ/N2H SoCs media: dt-bindings: media: renesas,fcp: Document RZ/T2H and RZ/N2H SoCs media: nxp: imx8-isi: Add additional 32-bit RGB format support media: nxp: imx8-isi: Add 16-bit raw Bayer format support media: nxp: imx8-isi: Implement per-stream reference counting for multiplexed streams media: nxp: imx8-isi: Use BIT_ULL() for 64-bit stream masks media: nxp: imx8-isi: Correct color map between V4L2 and ISI ...
Diffstat (limited to 'include/net/rps.h')
-rw-r--r--include/net/rps.h197
1 files changed, 197 insertions, 0 deletions
diff --git a/include/net/rps.h b/include/net/rps.h
new file mode 100644
index 000000000..e33c6a2fa
--- /dev/null
+++ b/include/net/rps.h
@@ -0,0 +1,197 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+#ifndef _NET_RPS_H
+#define _NET_RPS_H
+
+#include <linux/types.h>
+#include <linux/static_key.h>
+#include <net/sock.h>
+#include <net/hotdata.h>
+
+#ifdef CONFIG_RPS
+#include <net/rps-types.h>
+
+extern struct static_key_false rps_needed;
+extern struct static_key_false rfs_needed;
+
+/*
+ * This structure holds an RPS map which can be of variable length. The
+ * map is an array of CPUs.
+ */
+struct rps_map {
+ unsigned int len;
+ struct rcu_head rcu;
+ u16 cpus[];
+};
+#define RPS_MAP_SIZE(_num) (sizeof(struct rps_map) + ((_num) * sizeof(u16)))
+
+/*
+ * The rps_dev_flow structure contains the mapping of a flow to a CPU, the
+ * tail pointer for that CPU's input queue at the time of last enqueue, a
+ * hardware filter index, and the hash of the flow if aRFS is enabled.
+ */
+struct rps_dev_flow {
+ u16 cpu;
+ u16 filter;
+ unsigned int last_qtail;
+#ifdef CONFIG_RFS_ACCEL
+ u32 hash;
+#endif
+};
+#define RPS_NO_FILTER 0xffff
+
+/*
+ * The rps_sock_flow_table contains mappings of flows to the last CPU
+ * on which they were processed by the application (set in recvmsg).
+ * Each entry is a 32bit value. Upper part is the high-order bits
+ * of flow hash, lower part is CPU number.
+ * rps_cpu_mask is used to partition the space, depending on number of
+ * possible CPUs : rps_cpu_mask = roundup_pow_of_two(nr_cpu_ids) - 1
+ * For example, if 64 CPUs are possible, rps_cpu_mask = 0x3f,
+ * meaning we use 32-6=26 bits for the hash.
+ */
+struct rps_sock_flow_table {
+ u32 ent;
+};
+
+#define RPS_NO_CPU 0xffff
+
+static inline void rps_record_sock_flow(rps_tag_ptr tag_ptr, u32 hash)
+{
+ unsigned int index = hash & rps_tag_to_mask(tag_ptr);
+ u32 val = hash & ~net_hotdata.rps_cpu_mask;
+ struct rps_sock_flow_table *table;
+
+ /* We only give a hint, preemption can change CPU under us */
+ val |= raw_smp_processor_id();
+
+ table = rps_tag_to_table(tag_ptr);
+ /* The following WRITE_ONCE() is paired with the READ_ONCE()
+ * here, and another one in get_rps_cpu().
+ */
+ if (READ_ONCE(table[index].ent) != val)
+ WRITE_ONCE(table[index].ent, val);
+}
+
+static inline void _sock_rps_record_flow_hash(__u32 hash)
+{
+ rps_tag_ptr tag_ptr;
+
+ if (!hash)
+ return;
+ rcu_read_lock();
+ tag_ptr = READ_ONCE(net_hotdata.rps_sock_flow_table);
+ if (tag_ptr)
+ rps_record_sock_flow(tag_ptr, hash);
+ rcu_read_unlock();
+}
+
+static inline void _sock_rps_record_flow(const struct sock *sk)
+{
+ /* Reading sk->sk_rxhash might incur an expensive cache line
+ * miss.
+ *
+ * TCP_ESTABLISHED does cover almost all states where RFS
+ * might be useful, and is cheaper [1] than testing :
+ * IPv4: inet_sk(sk)->inet_daddr
+ * IPv6: ipv6_addr_any(&sk->sk_v6_daddr)
+ * OR an additional socket flag
+ * [1] : sk_state and sk_prot are in the same cache line.
+ */
+ if (sk->sk_state == TCP_ESTABLISHED) {
+ /* This READ_ONCE() is paired with the WRITE_ONCE()
+ * from sock_rps_save_rxhash() and sock_rps_reset_rxhash().
+ */
+ _sock_rps_record_flow_hash(READ_ONCE(sk->sk_rxhash));
+ }
+}
+
+static inline void _sock_rps_delete_flow(const struct sock *sk)
+{
+ struct rps_sock_flow_table *table;
+ rps_tag_ptr tag_ptr;
+ u32 hash, index;
+
+ hash = READ_ONCE(sk->sk_rxhash);
+ if (!hash)
+ return;
+
+ rcu_read_lock();
+ tag_ptr = READ_ONCE(net_hotdata.rps_sock_flow_table);
+ if (tag_ptr) {
+ index = hash & rps_tag_to_mask(tag_ptr);
+ table = rps_tag_to_table(tag_ptr);
+ if (READ_ONCE(table[index].ent) != RPS_NO_CPU)
+ WRITE_ONCE(table[index].ent, RPS_NO_CPU);
+ }
+ rcu_read_unlock();
+}
+#endif /* CONFIG_RPS */
+
+static inline bool rfs_is_needed(void)
+{
+#ifdef CONFIG_RPS
+ return static_branch_unlikely(&rfs_needed);
+#else
+ return false;
+#endif
+}
+
+static inline void sock_rps_record_flow_hash(__u32 hash)
+{
+#ifdef CONFIG_RPS
+ if (!rfs_is_needed())
+ return;
+
+ _sock_rps_record_flow_hash(hash);
+#endif
+}
+
+static inline void sock_rps_record_flow(const struct sock *sk)
+{
+#ifdef CONFIG_RPS
+ if (!rfs_is_needed())
+ return;
+
+ _sock_rps_record_flow(sk);
+#endif
+}
+
+static inline void sock_rps_delete_flow(const struct sock *sk)
+{
+#ifdef CONFIG_RPS
+ if (!rfs_is_needed())
+ return;
+
+ _sock_rps_delete_flow(sk);
+#endif
+}
+
+static inline u32 rps_input_queue_tail_incr(struct softnet_data *sd)
+{
+#ifdef CONFIG_RPS
+ return ++sd->input_queue_tail;
+#else
+ return 0;
+#endif
+}
+
+static inline void rps_input_queue_tail_save(u32 *dest, u32 tail)
+{
+#ifdef CONFIG_RPS
+ WRITE_ONCE(*dest, tail);
+#endif
+}
+
+static inline void rps_input_queue_head_add(struct softnet_data *sd, int val)
+{
+#ifdef CONFIG_RPS
+ WRITE_ONCE(sd->input_queue_head, sd->input_queue_head + val);
+#endif
+}
+
+static inline void rps_input_queue_head_incr(struct softnet_data *sd)
+{
+ rps_input_queue_head_add(sd, 1);
+}
+
+#endif /* _NET_RPS_H */