[PATCH net] octeontx2-pf: Fix lmtst Id used in aura free

[Geetha sowjanya]

Current code uses per_cpu pointer to get the lmtst_id mapped to
the core on which aura_free() is executed. Using per_cpu pointer
without preemption disable causing mismatch between lmtst_id and
core on which pointer gets freed. This patch fixes the issue by
disabling preemption around aura_free.

This patch also addresses the memory reservation issue,
currently NIX, NPA queue context memory is being allocated using
GFP_KERNEL flag which inturns allocates from memory reserved for
CMA_DMA. Sizing CMA_DMA memory is getting difficult due to this
dependency, the more number of interfaces enabled the more the
CMA_DMA memory requirement.

To fix this issue, GFP_KERNEL flag is replaced with GFP_ATOMIC,
with this memory will be allocated from unreserved memory.

Fixes: ef6c8da71eaf ("octeontx2-pf: cn10K: Reserve LMTST lines per core")
Signed-off-by: Sunil Goutham <sgoutham@xxxxxxxxxxx>
Signed-off-by: Geetha sowjanya <gakula@xxxxxxxxxxx>
---
 .../ethernet/marvell/octeontx2/af/common.h    |  2 +-
 .../marvell/octeontx2/nic/otx2_common.c       | 30 +++++++++++++------
 2 files changed, 22 insertions(+), 10 deletions(-)

diff --git a/drivers/net/ethernet/marvell/octeontx2/af/common.h b/drivers/net/ethernet/marvell/octeontx2/af/common.h
index 8931864ee110..4b4be9ca4d2f 100644
--- a/drivers/net/ethernet/marvell/octeontx2/af/common.h
+++ b/drivers/net/ethernet/marvell/octeontx2/af/common.h
@@ -61,7 +61,7 @@ static inline int qmem_alloc(struct device *dev, struct qmem **q,
 	qmem->entry_sz = entry_sz;
 	qmem->alloc_sz = (qsize * entry_sz) + OTX2_ALIGN;
 	qmem->base = dma_alloc_attrs(dev, qmem->alloc_sz, &qmem->iova,
-				     GFP_KERNEL, DMA_ATTR_FORCE_CONTIGUOUS);
+				     GFP_ATOMIC, DMA_ATTR_FORCE_CONTIGUOUS);
 	if (!qmem->base)
 		return -ENOMEM;
 
diff --git a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_common.c b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_common.c
index 9e10e7471b88..88f8772a61cd 100644
--- a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_common.c
+++ b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_common.c
@@ -1012,6 +1012,7 @@ static void otx2_pool_refill_task(struct work_struct *work)
 	rbpool = cq->rbpool;
 	free_ptrs = cq->pool_ptrs;
 
+	get_cpu();
 	while (cq->pool_ptrs) {
 		if (otx2_alloc_rbuf(pfvf, rbpool, &bufptr)) {
 			/* Schedule a WQ if we fails to free atleast half of the
@@ -1031,6 +1032,7 @@ static void otx2_pool_refill_task(struct work_struct *work)
 		pfvf->hw_ops->aura_freeptr(pfvf, qidx, bufptr + OTX2_HEAD_ROOM);
 		cq->pool_ptrs--;
 	}
+	put_cpu();
 	cq->refill_task_sched = false;
 }
 
@@ -1368,6 +1370,7 @@ int otx2_sq_aura_pool_init(struct otx2_nic *pfvf)
 	if (err)
 		goto fail;
 
+	get_cpu();
 	/* Allocate pointers and free them to aura/pool */
 	for (qidx = 0; qidx < hw->tot_tx_queues; qidx++) {
 		pool_id = otx2_get_pool_idx(pfvf, AURA_NIX_SQ, qidx);
@@ -1376,18 +1379,24 @@ int otx2_sq_aura_pool_init(struct otx2_nic *pfvf)
 		sq = &qset->sq[qidx];
 		sq->sqb_count = 0;
 		sq->sqb_ptrs = kcalloc(num_sqbs, sizeof(*sq->sqb_ptrs), GFP_KERNEL);
-		if (!sq->sqb_ptrs)
-			return -ENOMEM;
+		if (!sq->sqb_ptrs) {
+			err = -ENOMEM;
+			goto err_mem;
+		}
 
 		for (ptr = 0; ptr < num_sqbs; ptr++) {
-			if (otx2_alloc_rbuf(pfvf, pool, &bufptr))
-				return -ENOMEM;
+			err = otx2_alloc_rbuf(pfvf, pool, &bufptr);
+			if (err)
+				goto err_mem;
 			pfvf->hw_ops->aura_freeptr(pfvf, pool_id, bufptr);
 			sq->sqb_ptrs[sq->sqb_count++] = (u64)bufptr;
 		}
 	}
 
-	return 0;
+err_mem:
+	put_cpu();
+	return err ? -ENOMEM : 0;
+
 fail:
 	otx2_mbox_reset(&pfvf->mbox.mbox, 0);
 	otx2_aura_pool_free(pfvf);
@@ -1426,18 +1435,21 @@ int otx2_rq_aura_pool_init(struct otx2_nic *pfvf)
 	if (err)
 		goto fail;
 
+	get_cpu();
 	/* Allocate pointers and free them to aura/pool */
 	for (pool_id = 0; pool_id < hw->rqpool_cnt; pool_id++) {
 		pool = &pfvf->qset.pool[pool_id];
 		for (ptr = 0; ptr < num_ptrs; ptr++) {
-			if (otx2_alloc_rbuf(pfvf, pool, &bufptr))
-				return -ENOMEM;
+			err = otx2_alloc_rbuf(pfvf, pool, &bufptr);
+			if (err)
+				goto err_mem;
 			pfvf->hw_ops->aura_freeptr(pfvf, pool_id,
 						   bufptr + OTX2_HEAD_ROOM);
 		}
 	}
-
-	return 0;
+err_mem:
+	put_cpu();
+	return err ? -ENOMEM : 0;
 fail:
 	otx2_mbox_reset(&pfvf->mbox.mbox, 0);
 	otx2_aura_pool_free(pfvf);
-- 
2.25.1