Commit d34b0733 authored by Committed by Linus Torvalds
Revert "mm, page_alloc: only use per-cpu allocator for irq-safe requests"
This reverts commit 374ad05a. While the patch worked great for userspace allocations, the fact that softirq loses the per-cpu allocator caused problems. It needs to be redone taking into account that a separate list is needed for hard/soft IRQs or alternatively find a cheap way of detecting reentry due to an interrupt. Both are possible but sufficiently tricky that it shouldn't be rushed. Jesper had one method for allowing softirqs but reported that the cost was high enough that it performed similarly to a plain revert. His figures for netperf TCP_STREAM were as follows Baseline v4.10.0 : 60316 Mbit/s Current 4.11.0-rc6: 47491 Mbit/s Jesper's patch : 60662 Mbit/s This patch : 60106 Mbit/s As this is a regression, I wish to revert to noirq allocator for now and go back to the drawing board. Link: http://firstname.lastname@example.orgSigned-off-by: Mel Gorman <email@example.com> Reported-by: Tariq Toukan <firstname.lastname@example.org> Acked-by: Jesper Dangaard Brouer <email@example.com> Signed-off-by: Andrew Morton <firstname.lastname@example.org> Signed-off-by: Linus Torvalds <email@example.com>
Showing with 20 additions and 23 deletions