Messages in this thread Patch in this message | | | From | Rei Yamamoto <> | Subject | [PATCH] irq: consider cpus on nodes are unbalanced | Date | Fri, 29 Oct 2021 17:27:30 +0900 |
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If cpus on a node are offline at boot time, there are difference in the number of nodes between when building affinity masks for present cpus and when building affinity masks for possible cpus. This patch fixes 2 problems caused by the difference of the number of nodes:
- If some unused vectors remain after building masks for present cpus, remained vectors are assigned for building masks for possible cpus. Therefore "numvecs <= nodes" condition must be "vecs_to_assign <= nodes_to_assign". Fix this problem by making this condition appropriate.
- The routine of "numvecs <= nodes" condition can overwrite bits of masks for present cpus in building masks for possible cpus. Fix this problem by making CPU bits, which is not target, not changing.
Signed-off-by: Rei Yamamoto <yamamoto.rei@jp.fujitsu.com> --- kernel/irq/affinity.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-)
diff --git a/kernel/irq/affinity.c b/kernel/irq/affinity.c index f7ff8919dc9b..1cdf89e5e2fb 100644 --- a/kernel/irq/affinity.c +++ b/kernel/irq/affinity.c @@ -267,10 +267,16 @@ static int __irq_build_affinity_masks(unsigned int startvec, * If the number of nodes in the mask is greater than or equal the * number of vectors we just spread the vectors across the nodes. */ - if (numvecs <= nodes) { + if (numvecs - (curvec - firstvec) <= nodes) { for_each_node_mask(n, nodemsk) { + unsigned int ncpus; + + cpumask_and(nmsk, cpu_mask, node_to_cpumask[n]); + ncpus = cpumask_weight(nmsk); + if (!ncpus) + continue; cpumask_or(&masks[curvec].mask, &masks[curvec].mask, - node_to_cpumask[n]); + nmsk); if (++curvec == last_affv) curvec = firstvec; } -- 2.27.0
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