diff options
| -rw-r--r-- | mm/Kconfig | 11 | ||||
| -rw-r--r-- | mm/page_alloc.c | 2 |
2 files changed, 12 insertions, 1 deletions
diff --git a/mm/Kconfig b/mm/Kconfig index 45f2971ef642..89971a894b60 100644 --- a/mm/Kconfig +++ b/mm/Kconfig @@ -705,6 +705,17 @@ config HUGETLB_PAGE_SIZE_VARIABLE config CONTIG_ALLOC def_bool (MEMORY_ISOLATION && COMPACTION) || CMA +config PCP_BATCH_SCALE_MAX + int "Maximum scale factor of PCP (Per-CPU pageset) batch allocate/free" + default 5 + range 0 6 + help + In page allocator, PCP (Per-CPU pageset) is refilled and drained in + batches. The batch number is scaled automatically to improve page + allocation/free throughput. But too large scale factor may hurt + latency. This option sets the upper limit of scale factor to limit + the maximum latency. + config PHYS_ADDR_T_64BIT def_bool 64BIT diff --git a/mm/page_alloc.c b/mm/page_alloc.c index b76b1de48a30..05a8d34827d2 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -2340,7 +2340,7 @@ static int nr_pcp_free(struct per_cpu_pages *pcp, int high, bool free_high) * freeing of pages without any allocation. */ batch <<= pcp->free_factor; - if (batch < max_nr_free) + if (batch < max_nr_free && pcp->free_factor < CONFIG_PCP_BATCH_SCALE_MAX) pcp->free_factor++; batch = clamp(batch, min_nr_free, max_nr_free); |