diff mbox series

[net-next,v5,2/6] net: napi: add internal ARFS rmap management

Message ID 20250113171042.158123-3-ahmed.zaki@intel.com (mailing list archive)
State New
Delegated to: Netdev Maintainers
Headers show
Series net: napi: add CPU affinity to napi->config | expand

Checks

Context Check Description
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for net-next, async
netdev/ynl success Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 40 this patch: 40
netdev/build_tools success Errors and warnings before: 0 (+1) this patch: 0 (+1)
netdev/cc_maintainers success CCed 9 of 9 maintainers
netdev/build_clang success Errors and warnings before: 6616 this patch: 6616
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 4097 this patch: 4097
netdev/checkpatch warning CHECK: extern prototypes should be avoided in .h files
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 102 this patch: 102
netdev/source_inline success Was 1 now: 0
netdev/contest success net-next-2025-01-14--03-00 (tests: 885)

Commit Message

Ahmed Zaki Jan. 13, 2025, 5:10 p.m. UTC 
For drivers using the netif_enable_cpu_rmap(), move the IRQ rmap notifier
inside the napi_struct.

Signed-off-by: Ahmed Zaki <ahmed.zaki@intel.com>
---
 include/linux/cpu_rmap.h  |  1 +
 include/linux/netdevice.h |  4 ++
 lib/cpu_rmap.c            |  2 +-
 net/core/dev.c            | 77 ++++++++++++++++++++++++++++++++++++++-
 4 files changed, 81 insertions(+), 3 deletions(-)
diff mbox series

Patch

diff --git a/include/linux/cpu_rmap.h b/include/linux/cpu_rmap.h
index 20b5729903d7..2fd7ba75362a 100644
--- a/include/linux/cpu_rmap.h
+++ b/include/linux/cpu_rmap.h
@@ -32,6 +32,7 @@  struct cpu_rmap {
 #define CPU_RMAP_DIST_INF 0xffff
 
 extern struct cpu_rmap *alloc_cpu_rmap(unsigned int size, gfp_t flags);
+extern void cpu_rmap_get(struct cpu_rmap *rmap);
 extern int cpu_rmap_put(struct cpu_rmap *rmap);
 
 extern int cpu_rmap_add(struct cpu_rmap *rmap, void *obj);
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 7e95e9ee36dd..6f8b416aa32b 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -392,6 +392,10 @@  struct napi_struct {
 	struct list_head	dev_list;
 	struct hlist_node	napi_hash_node;
 	int			irq;
+#ifdef CONFIG_RFS_ACCEL
+	struct irq_affinity_notify notify;
+	int			napi_rmap_idx;
+#endif
 	int			index;
 	struct napi_config	*config;
 };
diff --git a/lib/cpu_rmap.c b/lib/cpu_rmap.c
index 4c348670da31..f03d9be3f06b 100644
--- a/lib/cpu_rmap.c
+++ b/lib/cpu_rmap.c
@@ -73,7 +73,7 @@  static void cpu_rmap_release(struct kref *ref)
  * cpu_rmap_get - internal helper to get new ref on a cpu_rmap
  * @rmap: reverse-map allocated with alloc_cpu_rmap()
  */
-static inline void cpu_rmap_get(struct cpu_rmap *rmap)
+void cpu_rmap_get(struct cpu_rmap *rmap)
 {
 	kref_get(&rmap->refcount);
 }
diff --git a/net/core/dev.c b/net/core/dev.c
index 3ee7a514dca8..c965d947b33d 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -6748,7 +6748,20 @@  EXPORT_SYMBOL(netif_queue_set_napi);
 #ifdef CONFIG_RFS_ACCEL
 static void netif_disable_cpu_rmap(struct net_device *dev)
 {
-	free_irq_cpu_rmap(dev->rx_cpu_rmap);
+	struct cpu_rmap *rmap = dev->rx_cpu_rmap;
+	struct napi_struct *napi;
+	u16 index;
+
+	if (!rmap || !dev->rx_cpu_rmap_auto)
+		return;
+
+	for (index = 0; index < rmap->size; index++) {
+		napi = rmap->obj[index];
+		if (napi && napi->irq > 0)
+			irq_set_affinity_notifier(napi->irq, NULL);
+	}
+
+	cpu_rmap_put(rmap);
 	dev->rx_cpu_rmap = NULL;
 	dev->rx_cpu_rmap_auto = false;
 }
@@ -6763,6 +6776,66 @@  int netif_enable_cpu_rmap(struct net_device *dev, unsigned int num_irqs)
 	return 0;
 }
 EXPORT_SYMBOL(netif_enable_cpu_rmap);
+
+static void
+netif_irq_cpu_rmap_notify(struct irq_affinity_notify *notify,
+			  const cpumask_t *mask)
+{
+	struct napi_struct *napi =
+		container_of(notify, struct napi_struct, notify);
+	struct cpu_rmap *rmap = napi->dev->rx_cpu_rmap;
+	int err;
+
+	if (rmap && napi->dev->rx_cpu_rmap_auto) {
+		err = cpu_rmap_update(rmap, napi->napi_rmap_idx, mask);
+		if (err)
+			pr_warn("%s: RMAP update failed (%d)\n",
+				__func__, err);
+	}
+}
+
+static void
+netif_napi_affinity_release(struct kref *ref)
+{
+	struct napi_struct *napi =
+		container_of(ref, struct napi_struct, notify.kref);
+	struct cpu_rmap *rmap = napi->dev->rx_cpu_rmap;
+
+	if (!rmap || !napi->dev->rx_cpu_rmap_auto)
+		return;
+
+	rmap->obj[napi->napi_rmap_idx] = NULL;
+	cpu_rmap_put(rmap);
+}
+
+static int napi_irq_cpu_rmap_add(struct napi_struct *napi, int irq)
+{
+	struct cpu_rmap *rmap = napi->dev->rx_cpu_rmap;
+	int rc;
+
+	if (!rmap)
+		return -EINVAL;
+
+	napi->notify.notify = netif_irq_cpu_rmap_notify;
+	napi->notify.release = netif_napi_affinity_release;
+	cpu_rmap_get(rmap);
+	rc = cpu_rmap_add(rmap, napi);
+	if (rc < 0)
+		goto err_add;
+
+	napi->napi_rmap_idx = rc;
+	rc = irq_set_affinity_notifier(irq, &napi->notify);
+	if (rc)
+		goto err_set;
+
+	return 0;
+
+err_set:
+	rmap->obj[napi->napi_rmap_idx] = NULL;
+err_add:
+	cpu_rmap_put(rmap);
+	return rc;
+}
 #endif
 
 void netif_napi_set_irq(struct napi_struct *napi, int irq)
@@ -6774,7 +6847,7 @@  void netif_napi_set_irq(struct napi_struct *napi, int irq)
 
 #ifdef CONFIG_RFS_ACCEL
 	if (napi->dev->rx_cpu_rmap && napi->dev->rx_cpu_rmap_auto) {
-		rc = irq_cpu_rmap_add(napi->dev->rx_cpu_rmap, irq);
+		rc = napi_irq_cpu_rmap_add(napi, irq);
 		if (rc) {
 			netdev_warn(napi->dev, "Unable to update ARFS map (%d)\n",
 				    rc);