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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /tools/testing/selftests/rcutorture/doc
parentInitial commit. (diff)
downloadlinux-upstream.tar.xz
linux-upstream.zip
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'tools/testing/selftests/rcutorture/doc')
-rw-r--r--tools/testing/selftests/rcutorture/doc/TINY_RCU.txt38
-rw-r--r--tools/testing/selftests/rcutorture/doc/TREE_RCU-kconfig.txt79
-rw-r--r--tools/testing/selftests/rcutorture/doc/initrd.txt16
-rw-r--r--tools/testing/selftests/rcutorture/doc/rcu-test-image.txt67
4 files changed, 200 insertions, 0 deletions
diff --git a/tools/testing/selftests/rcutorture/doc/TINY_RCU.txt b/tools/testing/selftests/rcutorture/doc/TINY_RCU.txt
new file mode 100644
index 000000000..a75b16991
--- /dev/null
+++ b/tools/testing/selftests/rcutorture/doc/TINY_RCU.txt
@@ -0,0 +1,38 @@
+This document gives a brief rationale for the TINY_RCU test cases.
+
+
+Kconfig Parameters:
+
+CONFIG_DEBUG_LOCK_ALLOC -- Do all three and none of the three.
+CONFIG_PREEMPT_COUNT
+CONFIG_RCU_TRACE
+
+The theory here is that randconfig testing will hit the other six possible
+combinations of these parameters.
+
+
+Kconfig Parameters Ignored:
+
+CONFIG_DEBUG_OBJECTS_RCU_HEAD
+CONFIG_PROVE_RCU
+
+ In common code tested by TREE_RCU test cases.
+
+CONFIG_RCU_NOCB_CPU
+
+ Meaningless for TINY_RCU.
+
+CONFIG_RCU_STALL_COMMON
+CONFIG_RCU_TORTURE_TEST
+
+ Redundant with CONFIG_RCU_TRACE.
+
+CONFIG_HOTPLUG_CPU
+CONFIG_PREEMPT
+CONFIG_PREEMPT_RCU
+CONFIG_SMP
+CONFIG_TINY_RCU
+CONFIG_PREEMPT_RCU
+CONFIG_TREE_RCU
+
+ All forced by CONFIG_TINY_RCU.
diff --git a/tools/testing/selftests/rcutorture/doc/TREE_RCU-kconfig.txt b/tools/testing/selftests/rcutorture/doc/TREE_RCU-kconfig.txt
new file mode 100644
index 000000000..42acb1a64
--- /dev/null
+++ b/tools/testing/selftests/rcutorture/doc/TREE_RCU-kconfig.txt
@@ -0,0 +1,79 @@
+This document gives a brief rationale for the TREE_RCU-related test
+cases, a group that includes PREEMPT_RCU.
+
+
+Kconfig Parameters:
+
+CONFIG_DEBUG_LOCK_ALLOC -- Do three, covering CONFIG_PROVE_LOCKING & not.
+CONFIG_DEBUG_OBJECTS_RCU_HEAD -- Do one.
+CONFIG_HZ_PERIODIC -- Do one.
+CONFIG_NO_HZ_IDLE -- Do those not otherwise specified. (Groups of two.)
+CONFIG_NO_HZ_FULL -- Do two, one with partial CPU enablement.
+CONFIG_PREEMPT -- Do half. (First three and #8.)
+CONFIG_PROVE_LOCKING -- Do several, covering CONFIG_DEBUG_LOCK_ALLOC=y and not.
+CONFIG_PROVE_RCU -- Hardwired to CONFIG_PROVE_LOCKING.
+CONFIG_RCU_BOOST -- one of PREEMPT_RCU.
+CONFIG_RCU_FANOUT -- Cover hierarchy, but overlap with others.
+CONFIG_RCU_FANOUT_LEAF -- Do one non-default.
+CONFIG_RCU_NOCB_CPU -- Do three, one with no rcu_nocbs CPUs, one with
+ rcu_nocbs=0, and one with all rcu_nocbs CPUs.
+CONFIG_RCU_TRACE -- Do half.
+CONFIG_SMP -- Need one !SMP for PREEMPT_RCU.
+CONFIG_RCU_EXPERT=n -- Do a few, but these have to be vanilla configurations.
+CONFIG_RCU_EQS_DEBUG -- Do at least one for CONFIG_NO_HZ_FULL and not.
+
+RCU-bh: Do one with PREEMPT and one with !PREEMPT.
+RCU-sched: Do one with PREEMPT but not BOOST.
+
+
+Boot parameters:
+
+nohz_full - do at least one.
+maxcpu -- do at least one.
+rcupdate.rcu_self_test_bh -- Do at least one each, offloaded and not.
+rcupdate.rcu_self_test_sched -- Do at least one each, offloaded and not.
+rcupdate.rcu_self_test -- Do at least one each, offloaded and not.
+rcutree.rcu_fanout_exact -- Do at least one.
+
+
+Kconfig Parameters Ignored:
+
+CONFIG_64BIT
+
+ Used only to check CONFIG_RCU_FANOUT value, inspection suffices.
+
+CONFIG_PREEMPT_COUNT
+CONFIG_PREEMPT_RCU
+
+ Redundant with CONFIG_PREEMPT, ignore.
+
+CONFIG_RCU_BOOST_DELAY
+
+ Inspection suffices, ignore.
+
+CONFIG_RCU_CPU_STALL_TIMEOUT
+
+ Inspection suffices, ignore.
+
+CONFIG_RCU_STALL_COMMON
+
+ Implied by TREE_RCU and PREEMPT_RCU.
+
+CONFIG_RCU_TORTURE_TEST
+CONFIG_RCU_TORTURE_TEST_RUNNABLE
+
+ Always used in KVM testing.
+
+CONFIG_PREEMPT_RCU
+CONFIG_TREE_RCU
+CONFIG_TINY_RCU
+CONFIG_TASKS_RCU
+
+ These are controlled by CONFIG_PREEMPT and/or CONFIG_SMP.
+
+CONFIG_SRCU
+
+ Selected by CONFIG_RCU_TORTURE_TEST, so cannot disable.
+
+
+boot parameters ignored: TBD
diff --git a/tools/testing/selftests/rcutorture/doc/initrd.txt b/tools/testing/selftests/rcutorture/doc/initrd.txt
new file mode 100644
index 000000000..41a425586
--- /dev/null
+++ b/tools/testing/selftests/rcutorture/doc/initrd.txt
@@ -0,0 +1,16 @@
+The rcutorture scripting tools automatically create an initrd containing
+a single statically linked binary named "init" that loops over a
+very long sleep() call. In both cases, this creation is done by
+tools/testing/selftests/rcutorture/bin/mkinitrd.sh.
+
+However, if you don't like the notion of statically linked bare-bones
+userspace environments, you might wish to press an existing initrd
+into service:
+
+------------------------------------------------------------------------
+cd tools/testing/selftests/rcutorture
+zcat /initrd.img > /tmp/initrd.img.zcat
+mkdir initrd
+cd initrd
+cpio -id < /tmp/initrd.img.zcat
+# Manually verify that initrd contains needed binaries and libraries.
diff --git a/tools/testing/selftests/rcutorture/doc/rcu-test-image.txt b/tools/testing/selftests/rcutorture/doc/rcu-test-image.txt
new file mode 100644
index 000000000..b2fc24797
--- /dev/null
+++ b/tools/testing/selftests/rcutorture/doc/rcu-test-image.txt
@@ -0,0 +1,67 @@
+Normally, a minimal initrd is created automatically by the rcutorture
+scripting. But minimal really does mean "minimal", namely just a single
+root directory with a single statically linked executable named "init":
+
+$ size tools/testing/selftests/rcutorture/initrd/init
+ text data bss dec hex filename
+ 328 0 8 336 150 tools/testing/selftests/rcutorture/initrd/init
+
+Suppose you need to run some scripts, perhaps to monitor or control
+some aspect of the rcutorture testing. This will require a more fully
+filled-out userspace, perhaps containing libraries, executables for
+the shell and other utilities, and soforth. In that case, place your
+desired filesystem here:
+
+ tools/testing/selftests/rcutorture/initrd
+
+For example, your tools/testing/selftests/rcutorture/initrd/init might
+be a script that does any needed mount operations and starts whatever
+scripts need starting to properly monitor or control your testing.
+The next rcutorture build will then incorporate this filesystem into
+the kernel image that is passed to qemu.
+
+Or maybe you need a real root filesystem for some reason, in which case
+please read on!
+
+The remainder of this document describes one way to create the
+rcu-test-image file that contains the filesystem used by the guest-OS
+kernel. There are probably much better ways of doing this, and this
+filesystem could no doubt be smaller. It is probably also possible to
+simply download an appropriate image from any number of places.
+
+That said, here are the commands:
+
+------------------------------------------------------------------------
+dd if=/dev/zero of=rcu-test-image bs=400M count=1
+mkfs.ext3 ./rcu-test-image
+sudo mount -o loop ./rcu-test-image /mnt
+
+# Replace "precise" below with your favorite Ubuntu release.
+# Empirical evidence says this image will work for 64-bit, but...
+# Note that debootstrap does take a few minutes to run. Or longer.
+sudo debootstrap --verbose --arch i386 precise /mnt http://archive.ubuntu.com/ubuntu
+cat << '___EOF___' | sudo dd of=/mnt/etc/fstab
+# UNCONFIGURED FSTAB FOR BASE SYSTEM
+#
+/dev/vda / ext3 defaults 1 1
+dev /dev tmpfs rw 0 0
+tmpfs /dev/shm tmpfs defaults 0 0
+devpts /dev/pts devpts gid=5,mode=620 0 0
+sysfs /sys sysfs defaults 0 0
+proc /proc proc defaults 0 0
+___EOF___
+sudo umount /mnt
+------------------------------------------------------------------------
+
+
+References:
+
+ http://sripathikodi.blogspot.com/2010/02/creating-kvm-bootable-fedora-system.html
+ https://help.ubuntu.com/community/KVM/CreateGuests
+ https://help.ubuntu.com/community/JeOSVMBuilder
+ http://wiki.libvirt.org/page/UbuntuKVMWalkthrough
+ http://www.moe.co.uk/2011/01/07/pci_add_option_rom-failed-to-find-romfile-pxe-rtl8139-bin/ -- "apt-get install kvm-pxe"
+ https://www.landley.net/writing/rootfs-howto.html
+ https://en.wikipedia.org/wiki/Initrd
+ https://en.wikipedia.org/wiki/Cpio
+ http://wiki.libvirt.org/page/UbuntuKVMWalkthrough