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octeontx2-af: Fix the size of memory allocated for the 'id_bmap' bitmap
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This allocation is really spurious.
The size of the bitmap is 'tot_ids' and it is used as such in the driver.

So we could expect something like:
   table->id_bmap = devm_kcalloc(rvu->dev, BITS_TO_LONGS(table->tot_ids),
			         sizeof(long), GFP_KERNEL);

However, when the bitmap is allocated, we allocate:
   BITS_TO_LONGS(table->tot_ids) * table->tot_ids ~=
   table->tot_ids / 32 * table->tot_ids ~=
   table->tot_ids^2 / 32

It is proportional to the square of 'table->tot_ids' which seems to
potentially be big.

Allocate the expected amount of memory, and switch to the bitmap API to
have it more straightforward.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://lore.kernel.org/r/ce2710771939065d68f95d86a27cf7cea7966365.1669378798.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Christophe JAILLET authored and Jakub Kicinski committed Dec 1, 2022
1 parent 05a7b52 commit 6d135d9
Showing 1 changed file with 2 additions and 2 deletions.
4 changes: 2 additions & 2 deletions drivers/net/ethernet/marvell/octeontx2/af/rvu_npc_hash.c
Original file line number Diff line number Diff line change
Expand Up @@ -1914,8 +1914,8 @@ int rvu_npc_exact_init(struct rvu *rvu)
dev_dbg(rvu->dev, "%s: Allocated bitmap for 32 entry cam\n", __func__);

table->tot_ids = (table->mem_table.depth * table->mem_table.ways) + table->cam_table.depth;
table->id_bmap = devm_kcalloc(rvu->dev, BITS_TO_LONGS(table->tot_ids),
table->tot_ids, GFP_KERNEL);
table->id_bmap = devm_bitmap_zalloc(rvu->dev, table->tot_ids,
GFP_KERNEL);

if (!table->id_bmap)
return -ENOMEM;
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