From 675e2694fc6c99effd6f07df296b1d806e49ec88 Mon Sep 17 00:00:00 2001 From: Christophe JAILLET Date: Wed, 24 Nov 2021 21:43:35 +0100 Subject: [PATCH] IB/mthca: Use non-atomic bitmap functions when possible in 'mthca_mr.c' 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 Signed-off-by: Jason Gunthorpe --- drivers/infiniband/hw/mthca/mthca_mr.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/drivers/infiniband/hw/mthca/mthca_mr.c b/drivers/infiniband/hw/mthca/mthca_mr.c index 8892fcdbac4c4..a59100c496b44 100644 --- a/drivers/infiniband/hw/mthca/mthca_mr.c +++ b/drivers/infiniband/hw/mthca/mthca_mr.c @@ -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; -- 2.30.2