Merge branch '100GbE' of git://git.kernel.org/pub/scm/linux/kernel/git/tnguy/next-queue

Tony Nguyen says:

====================
ice: support dynamic interrupt allocation

Piotr Raczynski says:

This patchset reimplements MSIX interrupt allocation logic to allow dynamic
interrupt allocation after MSIX has been initially enabled. This allows
current and future features to allocate and free interrupts as needed and
will help to drastically decrease number of initially preallocated
interrupts (even down to the API hard limit of 1). Although this patchset
does not change behavior in terms of actual number of allocated interrupts
during probe, it will be subject to change.

First few patches prepares to introduce dynamic allocation by moving
interrupt allocation code to separate file and update allocation API used
in the driver to the currently preferred one.

Due to the current contract between ice and irdma driver which is directly
accessing msix entries allocated by ice driver, even after moving away from
older pci_enable_msix_range function, still keep msix_entries array for
irdma use.

Next patches refactors and removes redundant code from SRIOV related logic
as it also make it easier to move away from static allocation scheme.

Last patches actually enables dynamic allocation of MSIX interrupts. First,
introduce functions to allocate and free interrupts individually. This sets
ground for the rest of the changes even if that patch still allocates the
interrupts from the preallocated pool. Since this patch starts to keep
interrupt details in ice_q_vector structure we can get rid of functions
that calculates base vector number and register offset for the interrupt
as it is equal to the interrupt index. Only keep separate register offset
functions for the VF VSIs.

Next, replace homegrown interrupt tracker with much simpler xarray based
approach. As new API always allocate interrupts one by one, also track
interrupts in the same manner.

Lastly, extend the interrupt tracker to deal both with preallocated and
dynamically allocated vectors and use pci_msix_alloc_irq_at and
pci_msix_free_irq functions. Since not all architecture supports dynamic
allocation, check it before trying to allocate a new interrupt.

As previously mentioned, this patchset does not change number of initially
allocated interrupts during init phase but now it can and will likely be
changed.

Patch 1-3 -> move code around and use newer API
Patch 4-5 -> refactor and remove redundant SRIOV code
Patch 6   -> allocate every interrupt individually
Patch 7   -> replace homegrown interrupt tracker with xarray
Patch 8   -> allow dynamic interrupt allocation
---
v2:
Patch 4
 - simplify ice_vsi_setup_vector_base and account for num_avail_sw_msix
Patch 8
 - prevent q_vector leak in case vf ctrl VSI error

v1: https://lore.kernel.org/netdev/20230509170048.2235678-1-anthony.l.nguyen@intel.com/
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 2 insertions, 286 deletions

diff --git a/drivers/net/ethernet/intel/ice/ice_lib.c b/drivers/net/ethernet/intel/ice/ice_lib.c
index 450317dfcca7..387bb9cbafbe 100644
--- a/drivers/net/ethernet/intel/ice/ice_lib.c
+++ b/drivers/net/ethernet/intel/ice/ice_lib.c
@@ -1371,190 +1371,6 @@ out:
 }
 
 /**
- * ice_free_res - free a block of resources
- * @res: pointer to the resource
- * @index: starting index previously returned by ice_get_res
- * @id: identifier to track owner
- *
- * Returns number of resources freed
- */
-int ice_free_res(struct ice_res_tracker *res, u16 index, u16 id)
-{
-	int count = 0;
-	int i;
-
-	if (!res || index >= res->end)
-		return -EINVAL;
-
-	id |= ICE_RES_VALID_BIT;
-	for (i = index; i < res->end && res->list[i] == id; i++) {
-		res->list[i] = 0;
-		count++;
-	}
-
-	return count;
-}
-
-/**
- * ice_search_res - Search the tracker for a block of resources
- * @res: pointer to the resource
- * @needed: size of the block needed
- * @id: identifier to track owner
- *
- * Returns the base item index of the block, or -ENOMEM for error
- */
-static int ice_search_res(struct ice_res_tracker *res, u16 needed, u16 id)
-{
-	u16 start = 0, end = 0;
-
-	if (needed > res->end)
-		return -ENOMEM;
-
-	id |= ICE_RES_VALID_BIT;
-
-	do {
-		/* skip already allocated entries */
-		if (res->list[end++] & ICE_RES_VALID_BIT) {
-			start = end;
-			if ((start + needed) > res->end)
-				break;
-		}
-
-		if (end == (start + needed)) {
-			int i = start;
-
-			/* there was enough, so assign it to the requestor */
-			while (i != end)
-				res->list[i++] = id;
-
-			return start;
-		}
-	} while (end < res->end);
-
-	return -ENOMEM;
-}
-
-/**
- * ice_get_free_res_count - Get free count from a resource tracker
- * @res: Resource tracker instance
- */
-static u16 ice_get_free_res_count(struct ice_res_tracker *res)
-{
-	u16 i, count = 0;
-
-	for (i = 0; i < res->end; i++)
-		if (!(res->list[i] & ICE_RES_VALID_BIT))
-			count++;
-
-	return count;
-}
-
-/**
- * ice_get_res - get a block of resources
- * @pf: board private structure
- * @res: pointer to the resource
- * @needed: size of the block needed
- * @id: identifier to track owner
- *
- * Returns the base item index of the block, or negative for error
- */
-int
-ice_get_res(struct ice_pf *pf, struct ice_res_tracker *res, u16 needed, u16 id)
-{
-	if (!res || !pf)
-		return -EINVAL;
-
-	if (!needed || needed > res->num_entries || id >= ICE_RES_VALID_BIT) {
-		dev_err(ice_pf_to_dev(pf), "param err: needed=%d, num_entries = %d id=0x%04x\n",
-			needed, res->num_entries, id);
-		return -EINVAL;
-	}
-
-	return ice_search_res(res, needed, id);
-}
-
-/**
- * ice_get_vf_ctrl_res - Get VF control VSI resource
- * @pf: pointer to the PF structure
- * @vsi: the VSI to allocate a resource for
- *
- * Look up whether another VF has already allocated the control VSI resource.
- * If so, re-use this resource so that we share it among all VFs.
- *
- * Otherwise, allocate the resource and return it.
- */
-static int ice_get_vf_ctrl_res(struct ice_pf *pf, struct ice_vsi *vsi)
-{
-	struct ice_vf *vf;
-	unsigned int bkt;
-	int base;
-
-	rcu_read_lock();
-	ice_for_each_vf_rcu(pf, bkt, vf) {
-		if (vf != vsi->vf && vf->ctrl_vsi_idx != ICE_NO_VSI) {
-			base = pf->vsi[vf->ctrl_vsi_idx]->base_vector;
-			rcu_read_unlock();
-			return base;
-		}
-	}
-	rcu_read_unlock();
-
-	return ice_get_res(pf, pf->irq_tracker, vsi->num_q_vectors,
-			   ICE_RES_VF_CTRL_VEC_ID);
-}
-
-/**
- * ice_vsi_setup_vector_base - Set up the base vector for the given VSI
- * @vsi: ptr to the VSI
- *
- * This should only be called after ice_vsi_alloc_def() which allocates the
- * corresponding SW VSI structure and initializes num_queue_pairs for the
- * newly allocated VSI.
- *
- * Returns 0 on success or negative on failure
- */
-static int ice_vsi_setup_vector_base(struct ice_vsi *vsi)
-{
-	struct ice_pf *pf = vsi->back;
-	struct device *dev;
-	u16 num_q_vectors;
-	int base;
-
-	dev = ice_pf_to_dev(pf);
-	/* SRIOV doesn't grab irq_tracker entries for each VSI */
-	if (vsi->type == ICE_VSI_VF)
-		return 0;
-	if (vsi->type == ICE_VSI_CHNL)
-		return 0;
-
-	if (vsi->base_vector) {
-		dev_dbg(dev, "VSI %d has non-zero base vector %d\n",
-			vsi->vsi_num, vsi->base_vector);
-		return -EEXIST;
-	}
-
-	num_q_vectors = vsi->num_q_vectors;
-	/* reserve slots from OS requested IRQs */
-	if (vsi->type == ICE_VSI_CTRL && vsi->vf) {
-		base = ice_get_vf_ctrl_res(pf, vsi);
-	} else {
-		base = ice_get_res(pf, pf->irq_tracker, num_q_vectors,
-				   vsi->idx);
-	}
-
-	if (base < 0) {
-		dev_err(dev, "%d MSI-X interrupts available. %s %d failed to get %d MSI-X vectors\n",
-			ice_get_free_res_count(pf->irq_tracker),
-			ice_vsi_type_str(vsi->type), vsi->idx, num_q_vectors);
-		return -ENOENT;
-	}
-	vsi->base_vector = (u16)base;
-	pf->num_avail_sw_msix -= num_q_vectors;
-
-	return 0;
-}
-
-/**
  * ice_vsi_clear_rings - Deallocates the Tx and Rx rings for VSI
  * @vsi: the VSI having rings deallocated
  */
@@ -2410,50 +2226,6 @@ static void ice_vsi_set_tc_cfg(struct ice_vsi *vsi)
 }
 
 /**
- * ice_vsi_set_q_vectors_reg_idx - set the HW register index for all q_vectors
- * @vsi: VSI to set the q_vectors register index on
- */
-static int
-ice_vsi_set_q_vectors_reg_idx(struct ice_vsi *vsi)
-{
-	u16 i;
-
-	if (!vsi || !vsi->q_vectors)
-		return -EINVAL;
-
-	ice_for_each_q_vector(vsi, i) {
-		struct ice_q_vector *q_vector = vsi->q_vectors[i];
-
-		if (!q_vector) {
-			dev_err(ice_pf_to_dev(vsi->back), "Failed to set reg_idx on q_vector %d VSI %d\n",
-				i, vsi->vsi_num);
-			goto clear_reg_idx;
-		}
-
-		if (vsi->type == ICE_VSI_VF) {
-			struct ice_vf *vf = vsi->vf;
-
-			q_vector->reg_idx = ice_calc_vf_reg_idx(vf, q_vector);
-		} else {
-			q_vector->reg_idx =
-				q_vector->v_idx + vsi->base_vector;
-		}
-	}
-
-	return 0;
-
-clear_reg_idx:
-	ice_for_each_q_vector(vsi, i) {
-		struct ice_q_vector *q_vector = vsi->q_vectors[i];
-
-		if (q_vector)
-			q_vector->reg_idx = 0;
-	}
-
-	return -EINVAL;
-}
-
-/**
  * ice_cfg_sw_lldp - Config switch rules for LLDP packet handling
  * @vsi: the VSI being configured
  * @tx: bool to determine Tx or Rx rule
@@ -2611,37 +2383,6 @@ static void ice_set_agg_vsi(struct ice_vsi *vsi)
 		vsi->agg_node->num_vsis);
 }
 
-/**
- * ice_free_vf_ctrl_res - Free the VF control VSI resource
- * @pf: pointer to PF structure
- * @vsi: the VSI to free resources for
- *
- * Check if the VF control VSI resource is still in use. If no VF is using it
- * any more, release the VSI resource. Otherwise, leave it to be cleaned up
- * once no other VF uses it.
- */
-static void ice_free_vf_ctrl_res(struct ice_pf *pf,  struct ice_vsi *vsi)
-{
-	struct ice_vf *vf;
-	unsigned int bkt;
-
-	rcu_read_lock();
-	ice_for_each_vf_rcu(pf, bkt, vf) {
-		if (vf != vsi->vf && vf->ctrl_vsi_idx != ICE_NO_VSI) {
-			rcu_read_unlock();
-			return;
-		}
-	}
-	rcu_read_unlock();
-
-	/* No other VFs left that have control VSI. It is now safe to reclaim
-	 * SW interrupts back to the common pool.
-	 */
-	ice_free_res(pf->irq_tracker, vsi->base_vector,
-		     ICE_RES_VF_CTRL_VEC_ID);
-	pf->num_avail_sw_msix += vsi->num_q_vectors;
-}
-
 static int ice_vsi_cfg_tc_lan(struct ice_pf *pf, struct ice_vsi *vsi)
 {
 	u16 max_txqs[ICE_MAX_TRAFFIC_CLASS] = { 0 };
@@ -2728,14 +2469,6 @@ ice_vsi_cfg_def(struct ice_vsi *vsi, struct ice_vsi_cfg_params *params)
 		if (ret)
 			goto unroll_vsi_init;
 
-		ret = ice_vsi_setup_vector_base(vsi);
-		if (ret)
-			goto unroll_alloc_q_vector;
-
-		ret = ice_vsi_set_q_vectors_reg_idx(vsi);
-		if (ret)
-			goto unroll_vector_base;
-
 		ret = ice_vsi_alloc_rings(vsi);
 		if (ret)
 			goto unroll_vector_base;
@@ -2786,10 +2519,6 @@ ice_vsi_cfg_def(struct ice_vsi *vsi, struct ice_vsi_cfg_params *params)
 		if (ret)
 			goto unroll_alloc_q_vector;
 
-		ret = ice_vsi_set_q_vectors_reg_idx(vsi);
-		if (ret)
-			goto unroll_vector_base;
-
 		ret = ice_vsi_alloc_ring_stats(vsi);
 		if (ret)
 			goto unroll_vector_base;
@@ -2822,8 +2551,6 @@ ice_vsi_cfg_def(struct ice_vsi *vsi, struct ice_vsi_cfg_params *params)
 
 unroll_vector_base:
 	/* reclaim SW interrupts back to the common pool */
-	ice_free_res(pf->irq_tracker, vsi->base_vector, vsi->idx);
-	pf->num_avail_sw_msix += vsi->num_q_vectors;
 unroll_alloc_q_vector:
 	ice_vsi_free_q_vectors(vsi);
 unroll_vsi_init:
@@ -2915,14 +2642,6 @@ void ice_vsi_decfg(struct ice_vsi *vsi)
 	 * many interrupts each VF needs. SR-IOV MSIX resources are also
 	 * cleared in the same manner.
 	 */
-	if (vsi->type == ICE_VSI_CTRL && vsi->vf) {
-		ice_free_vf_ctrl_res(pf, vsi);
-	} else if (vsi->type != ICE_VSI_VF) {
-		/* reclaim SW interrupts back to the common pool */
-		ice_free_res(pf->irq_tracker, vsi->base_vector, vsi->idx);
-		pf->num_avail_sw_msix += vsi->num_q_vectors;
-		vsi->base_vector = 0;
-	}
 
 	if (vsi->type == ICE_VSI_VF &&
 	    vsi->agg_node && vsi->agg_node->valid)
@@ -3039,7 +2758,6 @@ static void ice_vsi_release_msix(struct ice_vsi *vsi)
 void ice_vsi_free_irq(struct ice_vsi *vsi)
 {
 	struct ice_pf *pf = vsi->back;
-	int base = vsi->base_vector;
 	int i;
 
 	if (!vsi->q_vectors || !vsi->irqs_ready)
@@ -3053,10 +2771,9 @@ void ice_vsi_free_irq(struct ice_vsi *vsi)
 	ice_free_cpu_rx_rmap(vsi);
 
 	ice_for_each_q_vector(vsi, i) {
-		u16 vector = i + base;
 		int irq_num;
 
-		irq_num = pf->msix_entries[vector].vector;
+		irq_num = vsi->q_vectors[i]->irq.virq;
 
 		/* free only the irqs that were actually requested */
 		if (!vsi->q_vectors[i] ||
@@ -3188,7 +2905,6 @@ void ice_dis_vsi(struct ice_vsi *vsi, bool locked)
  */
 void ice_vsi_dis_irq(struct ice_vsi *vsi)
 {
-	int base = vsi->base_vector;
 	struct ice_pf *pf = vsi->back;
 	struct ice_hw *hw = &pf->hw;
 	u32 val;
@@ -3235,7 +2951,7 @@ void ice_vsi_dis_irq(struct ice_vsi *vsi)
 		return;
 
 	ice_for_each_q_vector(vsi, i)
-		synchronize_irq(pf->msix_entries[i + base].vector);
+		synchronize_irq(vsi->q_vectors[i]->irq.virq);
 }
 
 /**