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IB/mthca: Use non-atomic bitmap functions when possible in 'mthca_mr.c'

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In 'mthca_buddy_init()', the 'buddy->bits[n]' bitmap has just been
allocated, so no concurrent accesses can occur.

The other accesses to the 'buddy->bits[n]' bitmap are protected by the
'buddy->lock' spinlock, so no concurrent accesses can occur.

So prefer the non-atomic '__[set|clear]_bit()' functions to save a few
cycles.

Link: https://lore.kernel.org/r/a19b88ccdbc03972fd97306b998731814283041f.1637785902.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
This commit is contained in:
Christophe JAILLET
2021-11-24 21:43:35 +01:00
committed by Jason Gunthorpe
parent 19453f34cf
commit 675e2694fc
1 changed files with 5 additions and 5 deletions
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10
drivers/infiniband/hw/mthca/mthca_mr.c
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@@ -101,13 +101,13 @@ static u32 mthca_buddy_alloc(struct mthca_buddy *buddy, int order)
return -1;
found:
clear_bit(seg, buddy->bits[o]);
__clear_bit(seg, buddy->bits[o]);
--buddy->num_free[o];
while (o > order) {
--o;
seg <<= 1;
set_bit(seg ^ 1, buddy->bits[o]);
__set_bit(seg ^ 1, buddy->bits[o]);
++buddy->num_free[o];
}
@@ -125,13 +125,13 @@ static void mthca_buddy_free(struct mthca_buddy *buddy, u32 seg, int order)
spin_lock(&buddy->lock);
while (test_bit(seg ^ 1, buddy->bits[order])) {
clear_bit(seg ^ 1, buddy->bits[order]);
__clear_bit(seg ^ 1, buddy->bits[order]);
--buddy->num_free[order];
seg >>= 1;
++order;
}
set_bit(seg, buddy->bits[order]);
__set_bit(seg, buddy->bits[order]);
++buddy->num_free[order];
spin_unlock(&buddy->lock);
@@ -158,7 +158,7 @@ static int mthca_buddy_init(struct mthca_buddy *buddy, int max_order)
goto err_out_free;
}
set_bit(0, buddy->bits[buddy->max_order]);
__set_bit(0, buddy->bits[buddy->max_order]);
buddy->num_free[buddy->max_order] = 1;
return 0;