X-Git-Url: http://repo.macrolet.net/gitweb/?a=blobdiff_plain;f=src%2Fcompiler%2Fx86%2Fbackend-parms.lisp;h=16ea497f4a3608521b01c1d9101dfaca0e9176d0;hb=3d544b84f2b7ecd617d220145a775079df6c7919;hp=a1802f5e71a0584621fb8add3ae4829552bad68f;hpb=4d50265fe5a3dd4ea5b35c8ec12fe2b88721d22c;p=sbcl.git diff --git a/src/compiler/x86/backend-parms.lisp b/src/compiler/x86/backend-parms.lisp index a1802f5..16ea497 100644 --- a/src/compiler/x86/backend-parms.lisp +++ b/src/compiler/x86/backend-parms.lisp @@ -28,17 +28,12 @@ ;;; general have our C runtime code running to ask, so instead we set ;;; it by hand. -- WHN 2001-04-15 ;;; -;;; Though note that POSIX specifies (as far as I can tell) -;;; -;;; sysconf(_SC_PAGE_SIZE); -;;; -;;; as a portable way of retrieving this information; a call to this -;;; could be made in grovel-headers (which, strictly speaking, would -;;; no longer solely be grovelling headers), though the question of -;;; how to make this information appear in GENESIS, which is built and -;;; run from host-1 files (which are made before grovel-headers runs) -;;; would remain. -- CSR, 2002-09-01 -(setf *backend-page-size* 4096) +;;; Actually any information that we can retrieve C-side would be +;;; useless in SBCL, since it's possible for otherwise binary +;;; compatible systems to return different values for getpagesize(). +;;; -- JES, 2007-01-06 +(eval-when (:compile-toplevel :load-toplevel :execute) + (setf *backend-page-bytes* 4096)) ;;; comment from CMU CL: ;;; ;;; in case we ever wanted to do this for Windows NT.. @@ -48,4 +43,17 @@ ;;; page size is 512, but that doesn't do us a whole lot of good. ;;; Effectively, the page size is 64K. ;;; -;;; would be: (setf *backend-page-size* 65536) +;;; would be: (setf *backend-page-bytes* 65536) + +;;; The size in bytes of GENCGC cards, i.e. the granularity at which +;;; writes to old generations are logged. With mprotect-based write +;;; barriers, this must be a multiple of the OS page size. +(def!constant gencgc-card-bytes *backend-page-bytes*) +;;; The minimum size of new allocation regions. While it doesn't +;;; currently make a lot of sense to have a card size lower than +;;; the alloc granularity, it will, once we are smarter about finding +;;; the start of objects. +(def!constant gencgc-alloc-granularity 0) +;;; The minimum size at which we release address ranges to the OS. +;;; This must be a multiple of the OS page size. +(def!constant gencgc-release-granularity *backend-page-bytes*)