Date: Tue, 27 Apr 2010 05:35:35 +0000 (UTC) From: Alan Cox <alc@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r207262 - head/sys/i386/xen Message-ID: <201004270535.o3R5Zafj013748@svn.freebsd.org>
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Author: alc Date: Tue Apr 27 05:35:35 2010 New Revision: 207262 URL: http://svn.freebsd.org/changeset/base/207262 Log: MFi386 r207205 Clearing a page table entry's accessed bit (PG_A) and setting the page's PG_REFERENCED flag in pmap_protect() can't really be justified, so don't do it. Modified: head/sys/i386/xen/pmap.c Modified: head/sys/i386/xen/pmap.c ============================================================================== --- head/sys/i386/xen/pmap.c Tue Apr 27 05:18:02 2010 (r207261) +++ head/sys/i386/xen/pmap.c Tue Apr 27 05:35:35 2010 (r207262) @@ -2600,22 +2600,16 @@ retry: obits = pbits = *pte; if ((pbits & PG_V) == 0) continue; - if (pbits & PG_MANAGED) { - m = NULL; - if (pbits & PG_A) { - m = PHYS_TO_VM_PAGE(xpmap_mtop(pbits) & PG_FRAME); - vm_page_flag_set(m, PG_REFERENCED); - pbits &= ~PG_A; - } - if ((pbits & PG_M) != 0) { - if (m == NULL) - m = PHYS_TO_VM_PAGE(xpmap_mtop(pbits) & PG_FRAME); + + if ((prot & VM_PROT_WRITE) == 0) { + if ((pbits & (PG_MANAGED | PG_M | PG_RW)) == + (PG_MANAGED | PG_M | PG_RW)) { + m = PHYS_TO_VM_PAGE(xpmap_mtop(pbits) & + PG_FRAME); vm_page_dirty(m); } - } - - if ((prot & VM_PROT_WRITE) == 0) pbits &= ~(PG_RW | PG_M); + } #ifdef PAE if ((prot & VM_PROT_EXECUTE) == 0) pbits |= pg_nx;
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