Smitty

Documentation/vm/00-INDEX

@@ -14,6 +14,8 @@ hwpoison.txt
 	- explains what hwpoison is
 ksm.txt
 	- how to use the Kernel Samepage Merging feature.
+uksm.txt
+	- Introduction to Ultra KSM
 locking
 	- info on how locking and synchronization is done in the Linux vm code.
 map_hugetlb.c

Documentation/vm/uksm.txt

@@ -0,0 +1,57 @@
+The Ultra Kernel Samepage Merging feature
+----------------------------------------------
+/*
+ * Ultra KSM. Copyright (C) 2011-2012 Nai Xia
+ *
+ * This is an improvement upon KSM. Some basic data structures and routines
+ * are borrowed from ksm.c .
+ *
+ * Its new features:
+ * 1. Full system scan:
+ *      It automatically scans all user processes' anonymous VMAs. Kernel-user
+ *      interaction to submit a memory area to KSM is no longer needed.
+ *
+ * 2. Rich area detection:
+ *      It automatically detects rich areas containing abundant duplicated
+ *      pages based. Rich areas are given a full scan speed. Poor areas are
+ *      sampled at a reasonable speed with very low CPU consumption.
+ *
+ * 3. Ultra Per-page scan speed improvement:
+ *      A new hash algorithm is proposed. As a result, on a machine with
+ *      Core(TM)2 Quad Q9300 CPU in 32-bit mode and 800MHZ DDR2 main memory, it
+ *      can scan memory areas that does not contain duplicated pages at speed of
+ *      627MB/sec ~ 2445MB/sec and can merge duplicated areas at speed of
+ *      477MB/sec ~ 923MB/sec.
+ *
+ * 4. Thrashing area avoidance:
+ *      Thrashing area(an VMA that has frequent Ksm page break-out) can be
+ *      filtered out. My benchmark shows it's more efficient than KSM's per-page
+ *      hash value based volatile page detection.
+ *
+ *
+ * 5. Misc changes upon KSM:
+ *      * It has a fully x86-opitmized memcmp dedicated for 4-byte-aligned page
+ *        comparison. It's much faster than default C version on x86.
+ *      * rmap_item now has an struct *page member to loosely cache a
+ *        address-->page mapping, which reduces too much time-costly
+ *        follow_page().
+ *      * The VMA creation/exit procedures are hooked to let the Ultra KSM know.
+ *      * try_to_merge_two_pages() now can revert a pte if it fails. No break_
+ *        ksm is needed for this case.
+ *
+ * 6. Full Zero Page consideration(contributed by Figo Zhang)
+ *    Now uksmd consider full zero pages as special pages and merge them to an
+ *    special unswappable uksm zero page.
+ */
+
+ChangeLog:
+
+2012-05-05 The creation of this Doc
+2012-05-08 UKSM 0.1.1.1 libc crash bug fix, api clean up, doc clean up.
+2012-05-28 UKSM 0.1.1.2 bug fix release
+2012-06-26 UKSM 0.1.2-beta1 first beta release for 0.1.2
+2012-07-2  UKSM 0.1.2-beta2
+2012-07-10 UKSM 0.1.2-beta3
+2012-07-26 UKSM 0.1.2 Fine grained speed control, more scan optimization.
+2012-10-13 UKSM 0.1.2.1 Bug fixes.
+2012-12-31 UKSM 0.1.2.2 Minor bug fixes

Makefile

@@ -243,10 +243,15 @@ CONFIG_SHELL := $(shell if [ -x "$$BASH" ]; then echo $$BASH; \
 	  else if [ -x /bin/bash ]; then echo /bin/bash; \
 	  else echo sh; fi ; fi)
 
-HOSTCC       = gcc
-HOSTCXX      = g++
-HOSTCFLAGS   = -Wall -Wmissing-prototypes -Wstrict-prototypes -O2 -fomit-frame-pointer
-HOSTCXXFLAGS = -O2
+HOSTCC       = $(CCACHE) gcc
+HOSTCXX      = $(CCACHE) g++
+ifdef CCONFIG_CC_OPTIMIZE_O3
+ HOSTCFLAGS   = -Wall -W -Wmissing-prototypes -Wno-sign-compare -Wstrict-prototypes -Wno-unused-parameter -Wno-missing-field-initializers -O3 -fno-delete-null-pointer-checks
+ HOSTCXXFLAGS = -O3 -Wall -W -fno-delete-null-pointer-checks
+else
+ HOSTCFLAGS   = -Wall -W -Wmissing-prototypes -Wno-sign-compare -Wstrict-prototypes -Wno-unused-parameter -Wno-missing-field-initializers -O2 -fno-delete-null-pointer-checks
+ HOSTCXXFLAGS = -O2 -Wall -W -fno-delete-null-pointer-checks
+endif
 
 # Decide whether to build built-in, modular, or both.
 # Normally, just do built-in.
@@ -373,7 +378,13 @@ KBUILD_CFLAGS   := -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs \
                    -funswitch-loops -fpredictive-commoning -fgcse-after-reload \
 		   -fno-delete-null-pointer-checks
 KBUILD_AFLAGS_KERNEL :=
-KBUILD_CFLAGS_KERNEL :=
+
+ifdef CCONFIG_CC_OPTIMIZE_O3
+ KBUILD_CFLAGS_KERNEL := -O3 -mtune=cortex-a9 -march=armv7-a -mfpu=neon -ftree-vectorize
+else
+ KBUILD_CFLAGS_KERNEL := -O2 -mtune=cortex-a9 -march=armv7-a -mfpu=neon -ftree-vectorize
+endif
+
 KBUILD_AFLAGS   := -D__ASSEMBLY__
 KBUILD_AFLAGS_MODULE  := -DMODULE
 KBUILD_CFLAGS_MODULE  := -DMODULE
@@ -562,9 +573,13 @@ endif # $(dot-config)
 all: vmlinux
 
 ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
-KBUILD_CFLAGS	+= -Os
-else
-KBUILD_CFLAGS	+= -O2
+ KBUILD_CFLAGS	+= -Os
+endif
+ifdef CONFIG_CC_OPTIMIZE_DEFAULT
+ KBUILD_CFLAGS	+= -O2
+endif
+ifdef CONFIG_CC_OPTIMIZE_O3
+ KBUILD_CFLAGS  += -O3
 endif
 
 include $(srctree)/arch/$(SRCARCH)/Makefile

arch/arm/Kconfig

@@ -20,6 +20,7 @@ config ARM
 	select HAVE_KERNEL_GZIP
 	select HAVE_KERNEL_LZO
 	select HAVE_KERNEL_LZMA
+	select HAVE_KERNEL_XZ
 	select HAVE_IRQ_WORK
 	select HAVE_PERF_EVENTS
 	select PERF_USE_VMALLOC
@@ -1380,6 +1381,31 @@ config SMP_ON_UP
 
 	  If you don't know what to do here, say Y.
 
+config ARM_CPU_TOPOLOGY
+	bool "Support cpu topology definition"
+	depends on SMP && CPU_V7
+	default y
+	help
+	  Support ARM cpu topology definition. The MPIDR register defines
+	  affinity between processors which is then used to describe the cpu
+	  topology of an ARM System.
+
+config SCHED_MC
+	bool "Multi-core scheduler support"
+	depends on ARM_CPU_TOPOLOGY
+	help
+	  Multi-core scheduler support improves the CPU scheduler's decision
+	  making when dealing with multi-core CPU chips at a cost of slightly
+	  increased overhead in some places. If unsure say N here.
+
+config SCHED_SMT
+	bool "SMT scheduler support"
+	depends on ARM_CPU_TOPOLOGY
+	help
+	  Improves the CPU scheduler's decision making when dealing with
+	  MultiThreading at a cost of slightly increased overhead in some
+	  places. If unsure say N here.
+
 config HAVE_ARM_SCU
 	bool
 	depends on SMP
@@ -2086,3 +2112,4 @@ source "security/Kconfig"
 source "crypto/Kconfig"
 
 source "lib/Kconfig"
+

arch/arm/boot/compressed/Makefile

@@ -4,9 +4,8 @@
 # create a compressed vmlinuz image from the original vmlinux
 #
 
-plus_sec := $(call as-instr,.arch_extension sec,+sec)
-
 OBJS		=
+plus_sec := $(call as-instr,.arch_extension sec,+sec)
 
 # Ensure that mmcif loader code appears early in the image
 # to minimise that number of bocks that have to be read in
@@ -17,9 +16,16 @@ OBJS		+= mmcif-sh7372.o
 endif
 endif
 
-AFLAGS_head.o += -DTEXT_OFFSET=$(TEXT_OFFSET)
-HEAD	= head.o
-OBJS	+= misc.o decompress.o
+AFLAGS_head.o := -DTEXT_OFFSET=$(TEXT_OFFSET)
+AFLAGS_head.o += -Wa,-march=armv7-a$(plus_sec)
+HEAD = head.o
+
+AFLAGS_misc.o +=-Wa,-march=armv7-a$(plus_sec)
+MISC = misc.o
+
+AFLAGS_decompress.o += -Wa,-march=armv7-a$(plus_sec)
+DECOMPRESS = decompress.o
+
 FONTC	= $(srctree)/drivers/video/console/font_acorn_8x8.c
 
 #
@@ -84,21 +90,21 @@ SEDFLAGS	= s/TEXT_START/$(ZTEXTADDR)/;s/BSS_START/$(ZBSSADDR)/
 suffix_$(CONFIG_KERNEL_GZIP) = gzip
 suffix_$(CONFIG_KERNEL_LZO)  = lzo
 suffix_$(CONFIG_KERNEL_LZMA) = lzma
+suffix_$(CONFIG_KERNEL_XZ)   = xzkern 
 
 targets       := vmlinux vmlinux.lds \
 		 piggy.$(suffix_y) piggy.$(suffix_y).o \
 		 font.o font.c head.o misc.o $(OBJS)
 
 # Make sure files are removed during clean
-extra-y       += piggy.gzip piggy.lzo piggy.lzma lib1funcs.S
-
+extra-y       += piggy.gzip piggy.lzo piggy.lzma piggy.xzkern lib1funcs.S ashldi3.S 
 ifeq ($(CONFIG_FUNCTION_TRACER),y)
 ORIG_CFLAGS := $(KBUILD_CFLAGS)
 KBUILD_CFLAGS = $(subst -pg, , $(ORIG_CFLAGS))
 endif
 
 ccflags-y := -fpic -fno-builtin
-asflags-y := -Wa,-march=armv7-a$(plus_sec)
+asflags-y := -Wa,-march=armv7-a
 
 # Supply ZRELADDR to the decompressor via a linker symbol.
 ifneq ($(CONFIG_AUTO_ZRELADDR),y)
@@ -117,11 +123,18 @@ LDFLAGS_vmlinux += -X
 LDFLAGS_vmlinux += -T
 
 # For __aeabi_uidivmod
+AFLAGS_lib1funcs.o +=-Wa,-march=armv7-a$(plus_sec) 
 lib1funcs = $(obj)/lib1funcs.o
 
 $(obj)/lib1funcs.S: $(srctree)/arch/$(SRCARCH)/lib/lib1funcs.S FORCE
 	$(call cmd,shipped)
 
+# For __aeabi_llsl
+ashldi3 = $(obj)/ashldi3.o
+
+$(obj)/ashldi3.S: $(srctree)/arch/$(SRCARCH)/lib/ashldi3.S FORCE
+	$(call cmd,shipped)
+
 # We need to prevent any GOTOFF relocs being used with references
 # to symbols in the .bss section since we cannot relocate them
 # independently from the rest at run time.  This can be achieved by
@@ -135,14 +148,15 @@ bad_syms=$$($(CROSS_COMPILE)nm $@ | sed -n 's/^.\{8\} [bc] \(.*\)/\1/p') && \
   ( echo "following symbols must have non local/private scope:" >&2; \
     echo "$$bad_syms" >&2; rm -f $@; false )
 
-$(obj)/vmlinux: $(obj)/vmlinux.lds $(obj)/$(HEAD) $(obj)/piggy.$(suffix_y).o \
-	 	$(addprefix $(obj)/, $(OBJS)) $(lib1funcs) FORCE
+$(obj)/vmlinux: $(obj)/vmlinux.lds $(obj)/$(HEAD) $(obj)/$(MISC) $(obj)/$(DECOMPRESS) $(obj)/piggy.$(suffix_y).o \
+  $(addprefix $(obj)/, $(OBJS)) $(lib1funcs) $(ashldi3) FORCE 
 	$(call if_changed,ld)
 	@$(check_for_bad_syms)
 
 $(obj)/piggy.$(suffix_y): $(obj)/../Image FORCE
 	$(call if_changed,$(suffix_y))
 
+AFLAGS_piggy.$(suffix_y).o += -Wa,-march=armv7-a$(plus_sec) 
 $(obj)/piggy.$(suffix_y).o:  $(obj)/piggy.$(suffix_y) FORCE
 
 CFLAGS_font.o := -Dstatic=

arch/arm/boot/compressed/ashldi3.S

@@ -0,0 +1,53 @@
+/* Copyright 1995, 1996, 1998, 1999, 2000, 2003, 2004, 2005
+   Free Software Foundation, Inc.
+
+This file is free software; you can redistribute it and/or modify it
+under the terms of the GNU General Public License as published by the
+Free Software Foundation; either version 2, or (at your option) any
+later version.
+
+In addition to the permissions in the GNU General Public License, the
+Free Software Foundation gives you unlimited permission to link the
+compiled version of this file into combinations with other programs,
+and to distribute those combinations without any restriction coming
+from the use of this file.  (The General Public License restrictions
+do apply in other respects; for example, they cover modification of
+the file, and distribution when not linked into a combine
+executable.)
+
+This file is distributed in the hope that it will be useful, but
+WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program; see the file COPYING.  If not, write to
+the Free Software Foundation, 51 Franklin Street, Fifth Floor,
+Boston, MA 02110-1301, USA.  */
+
+
+#include <linux/linkage.h>
+
+#ifdef __ARMEB__
+#define al r1
+#define ah r0
+#else
+#define al r0
+#define ah r1
+#endif
+
+ENTRY(__ashldi3)
+ENTRY(__aeabi_llsl)
+
+	subs	r3, r2, #32
+	rsb	ip, r2, #32
+	movmi	ah, ah, lsl r2
+	movpl	ah, al, lsl r3
+ ARM(	orrmi	ah, ah, al, lsr ip	)
+ THUMB(	lsrmi	r3, al, ip		)
+ THUMB(	orrmi	ah, ah, r3		)
+	mov	al, al, lsl r2
+	mov	pc, lr
+
+ENDPROC(__ashldi3)
+ENDPROC(__aeabi_llsl)

arch/arm/boot/compressed/decompress.c

@@ -44,6 +44,10 @@ extern void error(char *);
 #include "../../../../lib/decompress_unlzma.c"
 #endif
 
+#ifdef CONFIG_KERNEL_XZ  
+#include "../../../../lib/decompress_unxz.c"  
+#endif
+
 int do_decompress(u8 *input, int len, u8 *output, void (*error)(char *x))
 {
 	return decompress(input, len, NULL, NULL, output, NULL, error);

arch/arm/boot/compressed/piggy.xzkern.S

@@ -0,0 +1,7 @@
+.section .piggydata,#alloc
+.globl input_data
+input_data:  
+.incbin "arch/arm/boot/compressed/piggy.xzkern"  
+.globl input_data_end  
+input_data_end:
+