Date: Sat, 25 Aug 2007 18:43:16 +0000 (UTC) From: Alan Cox <alc@FreeBSD.org> To: src-committers@FreeBSD.org, cvs-src@FreeBSD.org, cvs-all@FreeBSD.org Subject: cvs commit: src/sys/vm vm_fault.c Message-ID: <200708251843.l7PIhGNx094015@repoman.freebsd.org>
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alc 2007-08-25 18:43:16 UTC FreeBSD src repository Modified files: (Branch: RELENG_6) sys/vm vm_fault.c Log: MFC revision 1.234 Eliminate the special case handling of OBJT_DEVICE objects in vm_fault_additional_pages() that was introduced in revision 1.47. Then as now, it is unnecessary because dev_pager_haspage() returns zero for both the number of pages to read ahead and read behind, producing the same exact behavior by vm_fault_additional_pages() as the special case handling. MFC revision 1.235 Two changes to vm_fault_additional_pages(): 1. Rewrite the backward scan. Specifically, reverse the order in which pages are allocated so that upon failure it is never necessary to free pages that were just allocated. Moreover, any allocated pages can be put to use. This makes the backward scan behave just like the forward scan. 2. Eliminate an explicit, unsynchronized check for low memory before calling vm_page_alloc(). It serves no useful purpose. It is, in effect, optimizing the uncommon case at the expense of the common case. Revision Changes Path 1.205.2.7 +11 -28 src/sys/vm/vm_fault.c
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