Date: Tue, 14 Jun 2022 05:50:41 GMT From: Doug Moore <dougm@FreeBSD.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-main@FreeBSD.org Subject: git: 975715b78819 - main - iommu_gas: use to first-fit search for lowermatch Message-ID: <202206140550.25E5ofSK057355@gitrepo.freebsd.org>
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The branch main has been updated by dougm: URL: https://cgit.FreeBSD.org/src/commit/?id=975715b78819c6de68df15a6dd78157c6dba0fcb commit 975715b78819c6de68df15a6dd78157c6dba0fcb Author: Doug Moore <dougm@FreeBSD.org> AuthorDate: 2022-06-14 05:47:22 +0000 Commit: Doug Moore <dougm@FreeBSD.org> CommitDate: 2022-06-14 05:47:22 +0000 iommu_gas: use to first-fit search for lowermatch Reverse the order of the search for a free space in lowermatch, to make it a first-fit search. Iommu_gas_match_one always allocates from the beginning of the free gap discovered from searching the tree, so the current code isn't really allocating in a reverse first-fit anyway, and making the search first-fit reduces the number of iommu page table pages that are used. Reported by: alc Reviewed by: alc, kib MFC after: 3 weeks Differential Revision: https://reviews.freebsd.org/D35458 --- sys/dev/iommu/iommu_gas.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/sys/dev/iommu/iommu_gas.c b/sys/dev/iommu/iommu_gas.c index 221b404f2a45..e4f396d97fb7 100644 --- a/sys/dev/iommu/iommu_gas.c +++ b/sys/dev/iommu/iommu_gas.c @@ -387,18 +387,18 @@ iommu_gas_lowermatch(struct iommu_gas_match_args *a, struct iommu_map_entry *ent return (ENOMEM); if (entry->first >= a->common->lowaddr) return (ENOMEM); - child = RB_RIGHT(entry, rb_entry); + child = RB_LEFT(entry, rb_entry); if (child != NULL && 0 == iommu_gas_lowermatch(a, child)) return (0); - if (child != NULL && entry->end < a->common->lowaddr && - iommu_gas_match_one(a, entry->end, child->first, + if (child != NULL && child->last < a->common->lowaddr && + iommu_gas_match_one(a, child->last, entry->start, a->common->lowaddr)) { iommu_gas_match_insert(a); return (0); } - child = RB_LEFT(entry, rb_entry); - if (child != NULL && child->last < a->common->lowaddr && - iommu_gas_match_one(a, child->last, entry->start, + child = RB_RIGHT(entry, rb_entry); + if (child != NULL && entry->end < a->common->lowaddr && + iommu_gas_match_one(a, entry->end, child->first, a->common->lowaddr)) { iommu_gas_match_insert(a); return (0);
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