Commit-ID: 3412386b531244f24a27c79ee003506a52a00848
Gitweb: http://git.kernel.org/tip/3412386b531244f24a27c79ee003506a52a00848
Author: Keith Busch <[email protected]>
AuthorDate: Thu, 13 Apr 2017 13:28:12 -0400
Committer: Thomas Gleixner <[email protected]>
CommitDate: Thu, 13 Apr 2017 23:41:00 +0200
irq/affinity: Fix extra vecs calculation
This fixes a math error calculating the extra_vecs. The error assumed
only 1 cpu per vector, but the value needs to account for the actual
number of cpus per vector in order to get the correct remainder for
extra CPU assignment.
Fixes: 7bf8222b9bd0 ("irq/affinity: Fix CPU spread for unbalanced nodes")
Reported-by: Xiaolong Ye <[email protected]>
Signed-off-by: Keith Busch <[email protected]>
Link:
http://lkml.kernel.org/r/[email protected]
Signed-off-by: Thomas Gleixner <[email protected]>
---
kernel/irq/affinity.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/kernel/irq/affinity.c b/kernel/irq/affinity.c
index dc52911..d052947 100644
--- a/kernel/irq/affinity.c
+++ b/kernel/irq/affinity.c
@@ -108,7 +108,7 @@ irq_create_affinity_masks(int nvecs, const struct
irq_affinity *affd)
vecs_to_assign = min(vecs_per_node, ncpus);
/* Account for rounding errors */
- extra_vecs = ncpus - vecs_to_assign;
+ extra_vecs = ncpus - vecs_to_assign * (ncpus / vecs_to_assign);
for (v = 0; curvec < last_affv && v < vecs_to_assign;
curvec++, v++) {
