add threads and related syscalls

LICENSE

@@ -1,6 +1,6 @@
 The xv6 software is:
 
-Copyright (c) 2006-2024 Frans Kaashoek, Robert Morris, Russ Cox,
+Copyright (c) 2006-2019 Frans Kaashoek, Robert Morris, Russ Cox,
                         Massachusetts Institute of Technology
 
 Permission is hereby granted, free of charge, to any person obtaining

Makefile

@@ -1,3 +1,10 @@
+
+# To compile and run with a lab solution, set the lab name in lab.mk
+# (e.g., LB=util).  Run make grade to test solution with the lab's
+# grade script (e.g., grade-lab-util).
+
+-include conf/lab.mk
+
 K=kernel
 U=user
 
@@ -28,7 +35,11 @@ OBJS = \
   $K/sysfile.o \
   $K/kernelvec.o \
   $K/plic.o \
-  $K/virtio_disk.o
+  $K/virtio_disk.o \
+
+ifeq ($(LAB),pgtbl)
+OBJS += $K/vmcopyin.o
+endif
 
 # riscv64-unknown-elf- or riscv64-linux-gnu-
 # perhaps in /opt/riscv/bin
@@ -56,17 +67,26 @@ LD = $(TOOLPREFIX)ld
 OBJCOPY = $(TOOLPREFIX)objcopy
 OBJDUMP = $(TOOLPREFIX)objdump
 
-CFLAGS = -Wall -Werror -O -fno-omit-frame-pointer -ggdb -gdwarf-2
+CFLAGS = -Wall -Werror -O -fno-omit-frame-pointer -ggdb
+
+ifdef LAB_SYSCALL_TEST
+CFLAGS += -DLAB_SYSCALL_TEST
+endif
+
+GCC_VER12 := $(shell expr `gcc -dumpfullversion -dumpversion | sed -e 's/\.\([0-9][0-9]\)/\1/g' -e 's/\.\([0-9]\)/0\1/g' -e 's/^[0-9]\{3,4\}$$/&00/'` \>= 120000)
+ifeq "$(GCC_VER12)" "1"
+CFLAGS += -Wno-error=infinite-recursion
+endif
+
+
+ifdef LAB
+LABUPPER = $(shell echo $(LAB) | tr a-z A-Z)
+CFLAGS += -DSOL_$(LABUPPER)
+endif
+
 CFLAGS += -MD
 CFLAGS += -mcmodel=medany
-# CFLAGS += -ffreestanding -fno-common -nostdlib -mno-relax
-CFLAGS += -fno-common -nostdlib
-CFLAGS += -fno-builtin-strncpy -fno-builtin-strncmp -fno-builtin-strlen -fno-builtin-memset
-CFLAGS += -fno-builtin-memmove -fno-builtin-memcmp -fno-builtin-log -fno-builtin-bzero
-CFLAGS += -fno-builtin-strchr -fno-builtin-exit -fno-builtin-malloc -fno-builtin-putc
-CFLAGS += -fno-builtin-free
-CFLAGS += -fno-builtin-memcpy -Wno-main
-CFLAGS += -fno-builtin-printf -fno-builtin-fprintf -fno-builtin-vprintf
+CFLAGS += -ffreestanding -fno-common -nostdlib -mno-relax
 CFLAGS += -I.
 CFLAGS += $(shell $(CC) -fno-stack-protector -E -x c /dev/null >/dev/null 2>&1 && echo -fno-stack-protector)
 
@@ -97,7 +117,7 @@ tags: $(OBJS) _init
 ULIB = $U/ulib.o $U/usys.o $U/printf.o $U/umalloc.o
 
 _%: %.o $(ULIB)
-	$(LD) $(LDFLAGS) -T $U/user.ld -o $@ $^
+	$(LD) $(LDFLAGS) -N -e main -Ttext 0 -o $@ $^
 	$(OBJDUMP) -S $@ > $*.asm
 	$(OBJDUMP) -t $@ | sed '1,/SYMBOL TABLE/d; s/ .* / /; /^$$/d' > $*.sym
 
@@ -110,7 +130,7 @@ $U/usys.o : $U/usys.S
 $U/_forktest: $U/forktest.o $(ULIB)
 	# forktest has less library code linked in - needs to be small
 	# in order to be able to max out the proc table.
-	$(LD) $(LDFLAGS) -N -e main -Ttext 0 -o $U/_forktest $U/forktest.o $U/ulib.o $U/usys.o
+	$(LD) $(LDFLAGS) -N -e main -Ttext 0 -o $U/_forktest $U/forktest.o $U/ulib.o $U/usys.o $U/umalloc.o
 	$(OBJDUMP) -S $U/_forktest > $U/forktest.asm
 
 mkfs/mkfs: mkfs/mkfs.c $K/fs.h $K/param.h
@@ -139,9 +159,35 @@ UPROGS=\
 	$U/_grind\
 	$U/_wc\
 	$U/_zombie\
+	$U/_waittest\
+	$U/_exittest\
+	$U/_yieldtest\
+	$U/_threadtest\
+
+
+ifeq ($(LAB),trap)
+UPROGS += \
+	$U/_call\
+	$U/_alarmtest
+endif
 
-fs.img: mkfs/mkfs README $(UPROGS)
-	mkfs/mkfs fs.img README $(UPROGS)
+ifeq ($(LAB),lazy)
+UPROGS += \
+	$U/_lazytests
+endif
+
+ifeq ($(LAB),cow)
+UPROGS += \
+	$U/_cowtest
+endif
+
+UEXTRA=
+ifeq ($(LAB),util)
+	UEXTRA += user/xargstest.sh
+endif
+
+fs.img: mkfs/mkfs README $(UEXTRA) $(UPROGS)
+	mkfs/mkfs fs.img README $(UEXTRA) $(UPROGS)
 
 -include kernel/*.d user/*.d
 
@@ -164,7 +210,6 @@ CPUS := 3
 endif
 
 QEMUOPTS = -machine virt -bios none -kernel $K/kernel -m 128M -smp $(CPUS) -nographic
-QEMUOPTS += -global virtio-mmio.force-legacy=false
 QEMUOPTS += -drive file=fs.img,if=none,format=raw,id=x0
 QEMUOPTS += -device virtio-blk-device,drive=x0,bus=virtio-mmio-bus.0
 
@@ -178,3 +223,97 @@ qemu-gdb: $K/kernel .gdbinit fs.img
 	@echo "*** Now run 'gdb' in another window." 1>&2
 	$(QEMU) $(QEMUOPTS) -S $(QEMUGDB)
 
+##
+##  FOR testing lab grading script
+##
+
+ifneq ($(V),@)
+GRADEFLAGS += -v
+endif
+
+print-gdbport:
+	@echo $(GDBPORT)
+
+grade:
+	@echo $(MAKE) clean
+	@$(MAKE) clean || \
+          (echo "'make clean' failed.  HINT: Do you have another running instance of xv6?" && exit 1)
+	./grade-lab-$(LAB) $(GRADEFLAGS) --toolprefix $(TOOLPREFIX)
+
+format:
+	python3 clang-format.py
+
+diff:
+	git diff syscall-base HEAD > commit.patch
+
+##
+## FOR web handin
+##
+
+
+WEBSUB := https://6828.scripts.mit.edu/2020/handin.py
+
+handin: tarball-pref myapi.key
+	@SUF=$(LAB); \
+	curl -f -F file=@lab-$$SUF-handin.tar.gz -F key=\<myapi.key $(WEBSUB)/upload \
+	    > /dev/null || { \
+		echo ; \
+		echo Submit seems to have failed.; \
+		echo Please go to $(WEBSUB)/ and upload the tarball manually.; }
+
+handin-check:
+	@if ! test -d .git; then \
+		echo No .git directory, is this a git repository?; \
+		false; \
+	fi
+	@if test "$$(git symbolic-ref HEAD)" != refs/heads/$(LAB); then \
+		git branch; \
+		read -p "You are not on the $(LAB) branch.  Hand-in the current branch? [y/N] " r; \
+		test "$$r" = y; \
+	fi
+	@if ! git diff-files --quiet || ! git diff-index --quiet --cached HEAD; then \
+		git status -s; \
+		echo; \
+		echo "You have uncomitted changes.  Please commit or stash them."; \
+		false; \
+	fi
+	@if test -n "`git status -s`"; then \
+		git status -s; \
+		read -p "Untracked files will not be handed in.  Continue? [y/N] " r; \
+		test "$$r" = y; \
+	fi
+
+UPSTREAM := $(shell git remote -v | grep -m 1 "xv6-labs-2020" | awk '{split($$0,a," "); print a[1]}')
+
+tarball: handin-check
+	git archive --format=tar HEAD | gzip > lab-$(LAB)-handin.tar.gz
+
+tarball-pref: handin-check
+	@SUF=$(LAB); \
+	git archive --format=tar HEAD > lab-$$SUF-handin.tar; \
+	git diff $(UPSTREAM)/$(LAB) > /tmp/lab-$$SUF-diff.patch; \
+	tar -rf lab-$$SUF-handin.tar /tmp/lab-$$SUF-diff.patch; \
+	gzip -c lab-$$SUF-handin.tar > lab-$$SUF-handin.tar.gz; \
+	rm lab-$$SUF-handin.tar; \
+	rm /tmp/lab-$$SUF-diff.patch; \
+
+myapi.key:
+	@echo Get an API key for yourself by visiting $(WEBSUB)/
+	@read -p "Please enter your API key: " k; \
+	if test `echo "$$k" |tr -d '\n' |wc -c` = 32 ; then \
+		TF=`mktemp -t tmp.XXXXXX`; \
+		if test "x$$TF" != "x" ; then \
+			echo "$$k" |tr -d '\n' > $$TF; \
+			mv -f $$TF $@; \
+		else \
+			echo mktemp failed; \
+			false; \
+		fi; \
+	else \
+		echo Bad API key: $$k; \
+		echo An API key should be 32 characters long.; \
+		false; \
+	fi;
+
+
+.PHONY: handin tarball tarball-pref clean grade handin-check

README

@@ -6,41 +6,40 @@ ACKNOWLEDGMENTS
 
 xv6 is inspired by John Lions's Commentary on UNIX 6th Edition (Peer
 to Peer Communications; ISBN: 1-57398-013-7; 1st edition (June 14,
-2000)).  See also https://pdos.csail.mit.edu/6.1810/, which provides
-pointers to on-line resources for v6.
+2000)). See also https://pdos.csail.mit.edu/6.828/, which
+provides pointers to on-line resources for v6.
 
 The following people have made contributions: Russ Cox (context switching,
 locking), Cliff Frey (MP), Xiao Yu (MP), Nickolai Zeldovich, and Austin
 Clements.
 
 We are also grateful for the bug reports and patches contributed by
-Takahiro Aoyagi, Marcelo Arroyo, Silas Boyd-Wickizer, Anton Burtsev,
-carlclone, Ian Chen, Dan Cross, Cody Cutler, Mike CAT, Tej Chajed,
-Asami Doi,Wenyang Duan, eyalz800, Nelson Elhage, Saar Ettinger, Alice
-Ferrazzi, Nathaniel Filardo, flespark, Peter Froehlich, Yakir Goaron,
-Shivam Handa, Matt Harvey, Bryan Henry, jaichenhengjie, Jim Huang,
-Matúš Jókay, John Jolly, Alexander Kapshuk, Anders Kaseorg, kehao95,
-Wolfgang Keller, Jungwoo Kim, Jonathan Kimmitt, Eddie Kohler, Vadim
-Kolontsov, Austin Liew, l0stman, Pavan Maddamsetti, Imbar Marinescu,
-Yandong Mao, Matan Shabtay, Hitoshi Mitake, Carmi Merimovich, Mark
-Morrissey, mtasm, Joel Nider, Hayato Ohhashi, OptimisticSide,
-phosphagos, Harry Porter, Greg Price, RayAndrew, Jude Rich, segfault,
-Ayan Shafqat, Eldar Sehayek, Yongming Shen, Fumiya Shigemitsu, snoire,
-Taojie, Cam Tenny, tyfkda, Warren Toomey, Stephen Tu, Alissa Tung,
-Rafael Ubal, Amane Uehara, Pablo Ventura, Xi Wang, WaheedHafez,
-Keiichi Watanabe, Lucas Wolf, Nicolas Wolovick, wxdao, Grant Wu, x653,
-Jindong Zhang, Icenowy Zheng, ZhUyU1997, and Zou Chang Wei.
-
-ERROR REPORTS
+Silas Boyd-Wickizer, Anton Burtsev, Dan Cross, Cody Cutler, Mike CAT,
+Tej Chajed, Asami Doi, eyalz800, , Nelson Elhage, Saar Ettinger, Alice
+Ferrazzi, Nathaniel Filardo, Peter Froehlich, Yakir Goaron,Shivam
+Handa, Bryan Henry, jaichenhengjie, Jim Huang, Alexander Kapshuk,
+Anders Kaseorg, kehao95, Wolfgang Keller, Jonathan Kimmitt, Eddie
+Kohler, Austin Liew, Imbar Marinescu, Yandong Mao, Matan Shabtay,
+Hitoshi Mitake, Carmi Merimovich, Mark Morrissey, mtasm, Joel Nider,
+Greg Price, Ayan Shafqat, Eldar Sehayek, Yongming Shen, Fumiya
+Shigemitsu, Takahiro, Cam Tenny, tyfkda, Rafael Ubal, Warren Toomey,
+Stephen Tu, Pablo Ventura, Xi Wang, Keiichi Watanabe, Nicolas
+Wolovick, wxdao, Grant Wu, Jindong Zhang, Icenowy Zheng, and Zou Chang
+Wei.
+
+syscall
+The code in the files that constitute xv6 is
+Copyright 2006-2020 Frans Kaashoek, Robert Morris, and Russ Cox.
+
 
 Please send errors and suggestions to Frans Kaashoek and Robert Morris
-(kaashoek,[email protected]).  The main purpose of xv6 is as a teaching
-operating system for MIT's 6.1810, so we are more interested in
+(kaashoek,[email protected]). The main purpose of xv6 is as a teaching
+operating system for MIT's 6.S081, so we are more interested in
 simplifications and clarifications than new features.
 
 BUILDING AND RUNNING XV6
 
 You will need a RISC-V "newlib" tool chain from
 https://github.com/riscv/riscv-gnu-toolchain, and qemu compiled for
-riscv64-softmmu.  Once they are installed, and in your shell
+riscv64-softmmu. Once they are installed, and in your shell
 search path, you can run "make qemu".

clang-format.py

@@ -0,0 +1,13 @@
+import os
+
+c_extensions = (".c")
+
+for root, dirs, files in os.walk("kernel"):
+    for file in files:
+        if file.endswith(c_extensions):
+            os.system("clang-format -i -style=file " + root + "/" + file)
+
+for root, dirs, files in os.walk("user"):
+    for file in files:
+        if file.endswith(c_extensions):
+            os.system("clang-format -i -style=file " + root + "/" + file)

conf/lab.mk

@@ -0,0 +1 @@
+LAB=syscall

grade-lab-syscall

@@ -0,0 +1,53 @@
+#!/usr/bin/env python
+
+import re
+import subprocess
+from gradelib import *
+
+r = Runner(save("xv6.out"))
+
+@test(40, "exit test")
+def test_exit_test():
+    subprocess.run(["make", "clean"])
+    r.run_qemu(shell_script([
+        'exittest'
+    ]), make_args=["LAB_SYSCALL_TEST=on"])
+    r.match('proc \\d+ exit, parent pid \\d+, name \\w+, state \\w+')
+    r.match('proc \\d+ exit, child 0, pid \\d+, name \\w+, state \\w+')
+    r.match('proc \\d+ exit, child 1, pid \\d+, name \\w+, state \\w+')
+    r.match('proc \\d+ exit, child 2, pid \\d+, name \\w+, state \\w+')
+
+@test(40, "wait test")
+def test_wait_test():
+    r.run_qemu(shell_script([
+        'waittest'
+    ]), make_args=["LAB_SYSCALL_TEST=on"])
+    r.match('wait test OK')
+
+@test(19, "yield test")
+def test_yield_test():
+    r.run_qemu(shell_script([
+        'yieldtest'
+    ]), make_args=["CPUS=1", "LAB_SYSCALL_TEST=on"])
+    r.match("parent yield")
+    matches = re.findall("start to yield, user pc \w+", r.qemu.output, re.MULTILINE)
+    assert_equal(len(matches), 1)
+    sepc = matches[0][24:]
+    toolprefix = test_yield_test.options.toolprefix
+    result = subprocess.run([f"{toolprefix}addr2line", sepc, "-f", "-s", "-e", "user/_yieldtest"], stdout=subprocess.PIPE, check=True)
+    out = result.stdout.decode("utf-8")
+    assert(len(out) > 5)
+    assert_equal(out[:6], "yield\n")
+    r.match("switch to child 0")
+    r.match("switch to child 1")
+    r.match("switch to child 2")
+    r.match("parent yield finished")
+
+@test(1, "time")
+def test_time():
+    check_time()
+
+run_tests()
+
+
+