| Message ID | 1499007694-7231-3-git-send-email-sagi@grimberg.me (mailing list archive) |
|---|---|
| State | RFC |
| Headers | show |
On Sun, Jul 02, 2017 at 06:01:33PM +0300, Sagi Grimberg wrote: > A ULP might want to lookup an optimal completion vector based on > a given cpu core affinity. Expose a lookup routine for it iterating > on the device completion vectors searching a vector with affinity > matching the given cpu. Shouldn't this return the mask of cpus with the matching affinity instead of always the first one? -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
>> A ULP might want to lookup an optimal completion vector based on >> a given cpu core affinity. Expose a lookup routine for it iterating >> on the device completion vectors searching a vector with affinity >> matching the given cpu. > > Shouldn't this return the mask of cpus with the matching affinity > instead of always the first one? Its the opposite, I'm looking for the vector matching a given cpu. In case there are multiple vectors with the same cpu assignment, it doesn't really matter which one is it. -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/infiniband/core/verbs.c b/drivers/infiniband/core/verbs.c index 4792f5209ac2..f0dfb1ca952b 100644 --- a/drivers/infiniband/core/verbs.c +++ b/drivers/infiniband/core/verbs.c @@ -2099,3 +2099,44 @@ void ib_drain_qp(struct ib_qp *qp) ib_drain_rq(qp); } EXPORT_SYMBOL(ib_drain_qp); + +/** + * ib_find_cpu_vector() - Find the first completion vector mapped to a given cpu core + * @device: rdma device + * @cpu: cpu for the corresponding completion vector affinity + * @vector: output target completion vector + * + * If the device expose vector affinity we will search each of the vectors + * and if we find one that gives us the desired cpu core we return true + * and assign @vector to the corresponding completion vector. Otherwise + * we return false. We stop at the first appropriate completion vector + * we find as we don't have any preference for multiple vectors with the + * same affinity. + */ +bool ib_find_cpu_vector(struct ib_device *device, unsigned int cpu, + unsigned int *vector) +{ + bool found = false; + unsigned int c; + int vec; + + for (vec = 0; vec < device->num_comp_vectors; vec++) { + const struct cpumask *mask; + + mask = ib_get_vector_affinity(device, vec); + if (!mask) + goto out; + + for_each_cpu(c, mask) { + if (c == cpu) { + *vector = vec; + found = true; + goto out; + } + } + } + +out: + return found; +} +EXPORT_SYMBOL(ib_find_cpu_vector); diff --git a/include/rdma/ib_verbs.h b/include/rdma/ib_verbs.h index 2349143297c9..8af48ef811f8 100644 --- a/include/rdma/ib_verbs.h +++ b/include/rdma/ib_verbs.h @@ -3662,4 +3662,7 @@ ib_get_vector_affinity(struct ib_device *device, int comp_vector) } +bool ib_find_cpu_vector(struct ib_device *device, unsigned int cpu, + unsigned int *vector); + #endif /* IB_VERBS_H */
A ULP might want to lookup an optimal completion vector based on a given cpu core affinity. Expose a lookup routine for it iterating on the device completion vectors searching a vector with affinity matching the given cpu. Signed-off-by: Sagi Grimberg <sagi@grimberg.me> --- drivers/infiniband/core/verbs.c | 41 +++++++++++++++++++++++++++++++++++++++++ include/rdma/ib_verbs.h | 3 +++ 2 files changed, 44 insertions(+)