on 8/15/2023 4:53 PM, Baolin Wang wrote:
>
>
> On 8/5/2023 7:07 PM, Kemeng Shi wrote:
>> We always do zone_watermark_ok check and compaction_suitable check
>> together to test if compaction for target order should be runned.
>> Factor these code out for preparation to remove repeat code.
>>
>> Signed-off-by: Kemeng Shi <shikemeng@xxxxxxxxxxxxxxx>
>> ---
>> mm/compaction.c | 42 +++++++++++++++++++++++++++++-------------
>> 1 file changed, 29 insertions(+), 13 deletions(-)
>>
>> diff --git a/mm/compaction.c b/mm/compaction.c
>> index b5a699ed526b..26787ebb0297 100644
>> --- a/mm/compaction.c
>> +++ b/mm/compaction.c
>> @@ -2365,6 +2365,30 @@ bool compaction_zonelist_suitable(struct alloc_context *ac, int order,
>> return false;
>> }
>> +/*
>> + * Should we do compaction for target allocation order.
>> + * Return COMPACT_SUCCESS if allocation for target order can be already
>> + * satisfied
>> + * Return COMPACT_SKIPPED if compaction for target order is likely to fail
>> + * Return COMPACT_CONTINUE if compaction for target order should be runned
>> + */
>> +static inline enum compact_result
>> +compaction_suit_allocation_order(struct zone *zone, unsigned int order,
>> + int highest_zoneidx, unsigned int alloc_flags)
>> +{
>> + unsigned long watermark;
>> +
>> + watermark = wmark_pages(zone, alloc_flags & ALLOC_WMARK_MASK);
>
> IIUC, the watermark used in patch 8 and patch 9 is different, right? Have you measured the impact of modifying this watermark?
>
Actually, there is no functional change intended. Consider wmark_pages with
alloc_flags = 0 is equivalent to min_wmark_pages, patch 8 and patch 9 still
use original watermark.
>> + if (zone_watermark_ok(zone, order, watermark, highest_zoneidx,
>> + alloc_flags))
>> + return COMPACT_SUCCESS;
>> +
>> + if (!compaction_suitable(zone, order, highest_zoneidx))
>> + return COMPACT_SKIPPED;
>> +
>> + return COMPACT_CONTINUE;
>> +}
>> +
>> static enum compact_result
>> compact_zone(struct compact_control *cc, struct capture_control *capc)
>> {
>> @@ -2390,19 +2414,11 @@ compact_zone(struct compact_control *cc, struct capture_control *capc)
>> cc->migratetype = gfp_migratetype(cc->gfp_mask);
>> if (compaction_with_allocation_order(cc->order)) {
>> - unsigned long watermark;
>> -
>> - /* Allocation can already succeed, nothing to do */
>> - watermark = wmark_pages(cc->zone,
>> - cc->alloc_flags & ALLOC_WMARK_MASK);
>> - if (zone_watermark_ok(cc->zone, cc->order, watermark,
>> - cc->highest_zoneidx, cc->alloc_flags))
>> - return COMPACT_SUCCESS;
>> -
>> - /* Compaction is likely to fail */
>> - if (!compaction_suitable(cc->zone, cc->order,
>> - cc->highest_zoneidx))
>> - return COMPACT_SKIPPED;
>> + ret = compaction_suit_allocation_order(cc->zone, cc->order,
>> + cc->highest_zoneidx,
>> + cc->alloc_flags);
>> + if (ret != COMPACT_CONTINUE)
>> + return ret;
>> }
>> /*
>
>
