On 2/23/24 9:27 PM, Qais Yousef wrote: > Due to recent changes in how topology is represented on asymmetric multi > processing systems like big.LITTLE where all cpus share the last LLC, there is > a performance regression as cpus with different compute capacities appear under > the same LLC and we no longer send an IPI when the requester is running on > a different cluster with different compute capacity. > > Restore the old behavior by adding a new cpus_equal_capacity() function to help > check for the new condition for these systems. > > Changes since v1: > > * Split the patch per subsystem. > * Convert cpus_gte_capacity() to cpus_equal_capacity() > * Make cpus_equal_capacity() return immediately for SMP systems. > nit: Did you mean !SMP systems here? Because in changes i see its returning true directly if its in !CONFIG_SMP path. > Qais Yousef (2): > sched: Add a new function to compare if two cpus have the same > capacity > block/blk-mq: Don't complete locally if capacities are different > > block/blk-mq.c | 5 +++-- > include/linux/sched/topology.h | 6 ++++++ > kernel/sched/core.c | 11 +++++++++++ > 3 files changed, 20 insertions(+), 2 deletions(-) >
