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charset="UTF-8" X-Rspamd-Server: rspam12 X-Rspamd-Queue-Id: 9BD4B180012 X-Stat-Signature: u6h86ya9gyghih7go9ucm7oztrmg6pnj X-Rspam-User: X-HE-Tag: 1757965948-374537 X-HE-Meta: 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 Qipuw6Sr 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: When the CMA_BALANCE flag is set for a CMA area, it means that it opts in to CMA balancing. This means two things: 1) It allows movable allocations to be migrated in to it in the case of a CMA inbalance (too much free memory in CMA pageblocks as compared to other pageblocks). 2) It is allocated top-down, so that compaction will end up migrating pages in to it. Doing this will make sure that compaction doesn't aggrevate a CMA imbalance, and that it won't fight with CMA balance migration from non-CMA to CMA. Signed-off-by: Frank van der Linden --- include/linux/cma.h | 4 +++- mm/cma.c | 33 ++++++++++++++++++++++++++------- 2 files changed, 29 insertions(+), 8 deletions(-) diff --git a/include/linux/cma.h b/include/linux/cma.h index 0504580d61d0..6e98a516b336 100644 --- a/include/linux/cma.h +++ b/include/linux/cma.h @@ -26,6 +26,7 @@ enum cma_flags { __CMA_ZONES_INVALID, __CMA_ACTIVATED, __CMA_FIXED, + __CMA_BALANCE, }; #define CMA_RESERVE_PAGES_ON_ERROR BIT(__CMA_RESERVE_PAGES_ON_ERROR) @@ -33,8 +34,9 @@ enum cma_flags { #define CMA_ZONES_INVALID BIT(__CMA_ZONES_INVALID) #define CMA_ACTIVATED BIT(__CMA_ACTIVATED) #define CMA_FIXED BIT(__CMA_FIXED) +#define CMA_BALANCE BIT(__CMA_BALANCE) -#define CMA_INIT_FLAGS (CMA_FIXED|CMA_RESERVE_PAGES_ON_ERROR) +#define CMA_INIT_FLAGS (CMA_FIXED|CMA_RESERVE_PAGES_ON_ERROR|CMA_BALANCE) struct cma; struct zone; diff --git a/mm/cma.c b/mm/cma.c index 53cb1833407b..6050d57f3c2e 100644 --- a/mm/cma.c +++ b/mm/cma.c @@ -272,6 +272,9 @@ static bool cma_next_free_range(struct cma_memrange *cmr, static inline bool cma_should_balance_range(struct zone *zone, struct cma_memrange *cmr) { + if (!(cmr->cma->flags & CMA_BALANCE)) + return false; + if (page_zone(pfn_to_page(cmr->base_pfn)) != zone) return false; @@ -527,6 +530,12 @@ static bool __init basecmp(struct cma_init_memrange *mlp, return mlp->base < mrp->base; } +static bool __init revbasecmp(struct cma_init_memrange *mlp, + struct cma_init_memrange *mrp) +{ + return mlp->base > mrp->base; +} + /* * Helper function to create sorted lists. */ @@ -575,7 +584,8 @@ static int __init cma_fixed_reserve(phys_addr_t base, phys_addr_t size) } static phys_addr_t __init cma_alloc_mem(phys_addr_t base, phys_addr_t size, - phys_addr_t align, phys_addr_t limit, int nid) + phys_addr_t align, phys_addr_t limit, int nid, + unsigned long flags) { phys_addr_t addr = 0; @@ -588,7 +598,8 @@ static phys_addr_t __init cma_alloc_mem(phys_addr_t base, phys_addr_t size, * like DMA/DMA32. */ #ifdef CONFIG_PHYS_ADDR_T_64BIT - if (!memblock_bottom_up() && limit >= SZ_4G + size) { + if (!(flags & CMA_BALANCE) && !memblock_bottom_up() + && limit >= SZ_4G + size) { memblock_set_bottom_up(true); addr = memblock_alloc_range_nid(size, align, SZ_4G, limit, nid, true); @@ -695,7 +706,7 @@ static int __init __cma_declare_contiguous_nid(phys_addr_t *basep, if (ret) return ret; } else { - base = cma_alloc_mem(base, size, alignment, limit, nid); + base = cma_alloc_mem(base, size, alignment, limit, nid, flags); if (!base) return -ENOMEM; @@ -851,7 +862,10 @@ int __init cma_declare_contiguous_multi(phys_addr_t total_size, list_for_each_safe(mp, next, &ranges) { mlp = list_entry(mp, struct cma_init_memrange, list); list_del(mp); - list_insert_sorted(&final_ranges, mlp, basecmp); + if (flags & CMA_BALANCE) + list_insert_sorted(&final_ranges, mlp, revbasecmp); + else + list_insert_sorted(&final_ranges, mlp, basecmp); sizesum += mlp->size; if (sizesum >= total_size) break; @@ -866,7 +880,12 @@ int __init cma_declare_contiguous_multi(phys_addr_t total_size, list_for_each(mp, &final_ranges) { mlp = list_entry(mp, struct cma_init_memrange, list); size = min(sizeleft, mlp->size); - if (memblock_reserve(mlp->base, size)) { + if (flags & CMA_BALANCE) + start = (mlp->base + mlp->size - size); + else + start = mlp->base; + + if (memblock_reserve(start, size)) { /* * Unexpected error. Could go on to * the next one, but just abort to @@ -877,9 +896,9 @@ int __init cma_declare_contiguous_multi(phys_addr_t total_size, } pr_debug("created region %d: %016llx - %016llx\n", - nr, (u64)mlp->base, (u64)mlp->base + size); + nr, (u64)start, (u64)start + size); cmrp = &cma->ranges[nr++]; - cmrp->base_pfn = PHYS_PFN(mlp->base); + cmrp->base_pfn = PHYS_PFN(start); cmrp->early_pfn = cmrp->base_pfn; cmrp->count = size >> PAGE_SHIFT; cmrp->cma = cma; -- 2.51.0.384.g4c02a37b29-goog