Commit Graph

268 Commits

Author SHA1 Message Date
Linus Torvalds
67a2422239 for-5.2/block-20190507
-----BEGIN PGP SIGNATURE-----
 
 iQJEBAABCAAuFiEEwPw5LcreJtl1+l5K99NY+ylx4KYFAlzR0AAQHGF4Ym9lQGtl
 cm5lbC5kawAKCRD301j7KXHgpo0MD/47D1kBK9rGzkAwIz1Jkh1Qy/ITVaDJzmHJ
 UP5uncQsgKFLKMR1LbRcrWtmk2MwFDNULGbteHFeCYE1ypCrTgpWSp5+SJluKd1Q
 hma9krLSAXO9QiSaZ4jafshXFIZxz6IjakOW8c9LrT80Ze47yh7AxiLwDafcp/Jj
 x6NW790qB7ENDtfarDkZk14NCS8HGLRHO5B21LB+hT0Kfbh0XZaLzJdj7Mck1wPA
 VT8hL9mPuA++AjF7Ra4kUjwSakgmajTa3nS2fpkwTYdztQfas7x5Jiv7FWxrrelb
 qbabkNkWKepcHAPEiZR7o53TyfCucGeSK/jG+dsJ9KhNp26kl1ci3frl5T6PfVMP
 SPPDjsKIHs+dqFrU9y5rSGhLJqewTs96hHthnLGxyF67+5sRb5+YIy+dcqgiyc/b
 TUVyjCD6r0cO2q4v9VhwnhOyeBUA9Rwbu8nl7JV5Q45uG7qI4BC39l1jfubMNDPO
 GLNGUUzb6ER7z6lYINjRSF2Jhejsx8SR9P7jhpb1Q7k/VvDDxO1T4FpwvqWFz9+s
 Gn+s6//+cA6LL+42eZkQjvwF2CUNE7TaVT8zdb+s5HP1RQkZToqUnsQCGeRTrFni
 RqWXfW9o9+awYRp431417oMdX/LvLGq9+ZtifRk9DqDcowXevTaf0W2RpplWSuiX
 RcCuPeLAVg==
 =Ot0g
 -----END PGP SIGNATURE-----

Merge tag 'for-5.2/block-20190507' of git://git.kernel.dk/linux-block

Pull block updates from Jens Axboe:
 "Nothing major in this series, just fixes and improvements all over the
  map. This contains:

   - Series of fixes for sed-opal (David, Jonas)

   - Fixes and performance tweaks for BFQ (via Paolo)

   - Set of fixes for bcache (via Coly)

   - Set of fixes for md (via Song)

   - Enabling multi-page for passthrough requests (Ming)

   - Queue release fix series (Ming)

   - Device notification improvements (Martin)

   - Propagate underlying device rotational status in loop (Holger)

   - Removal of mtip32xx trim support, which has been disabled for years
     (Christoph)

   - Improvement and cleanup of nvme command handling (Christoph)

   - Add block SPDX tags (Christoph)

   - Cleanup/hardening of bio/bvec iteration (Christoph)

   - A few NVMe pull requests (Christoph)

   - Removal of CONFIG_LBDAF (Christoph)

   - Various little fixes here and there"

* tag 'for-5.2/block-20190507' of git://git.kernel.dk/linux-block: (164 commits)
  block: fix mismerge in bvec_advance
  block: don't drain in-progress dispatch in blk_cleanup_queue()
  blk-mq: move cancel of hctx->run_work into blk_mq_hw_sysfs_release
  blk-mq: always free hctx after request queue is freed
  blk-mq: split blk_mq_alloc_and_init_hctx into two parts
  blk-mq: free hw queue's resource in hctx's release handler
  blk-mq: move cancel of requeue_work into blk_mq_release
  blk-mq: grab .q_usage_counter when queuing request from plug code path
  block: fix function name in comment
  nvmet: protect discovery change log event list iteration
  nvme: mark nvme_core_init and nvme_core_exit static
  nvme: move command size checks to the core
  nvme-fabrics: check more command sizes
  nvme-pci: check more command sizes
  nvme-pci: remove an unneeded variable initialization
  nvme-pci: unquiesce admin queue on shutdown
  nvme-pci: shutdown on timeout during deletion
  nvme-pci: fix psdt field for single segment sgls
  nvme-multipath: don't print ANA group state by default
  nvme-multipath: split bios with the ns_head bio_set before submitting
  ...
2019-05-07 18:14:36 -07:00
Christoph Hellwig
72deb455b5 block: remove CONFIG_LBDAF
Currently support for 64-bit sector_t and blkcnt_t is optional on 32-bit
architectures.  These types are required to support block device and/or
file sizes larger than 2 TiB, and have generally defaulted to on for
a long time.  Enabling the option only increases the i386 tinyconfig
size by 145 bytes, and many data structures already always use
64-bit values for their in-core and on-disk data structures anyway,
so there should not be a large change in dynamic memory usage either.

Dropping this option removes a somewhat weird non-default config that
has cause various bugs or compiler warnings when actually used.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-04-06 10:48:35 -06:00
Paul E. McKenney
164a4daaea torture: Suppress false-positive CONFIG_INITRAMFS_SOURCE complaint
The scripting must supply the CONFIG_INITRAMFS_SOURCE Kconfig option
so that kbuild can find the desired initrd, but the configcheck.sh
script gets confused by this option because it takes a string instead
of the expected y/n/m.  This causes checkconfig.sh to complain about
CONFIG_INITRAMFS_SOURCE in the torture-test output (though not in the
summary).  As more people use rcutorture, the resulting confusion is
an increasing concern.

This commit therefore suppresses this false-positive warning by filtering
CONFIG_INITRAMFS_SOURCE from within the checkconfig.sh script.

Reported-by: Joel Fernandes <joel@joelfernandes.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-03-26 14:42:53 -07:00
Paul E. McKenney
fef141f619 tools/.../rcutorture: Convert to SPDX license identifier
Replace the license boiler plate with a SPDX license identifier.
While in the area, update an email address and add copyright notices.

Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-03-26 14:42:53 -07:00
Willy Tarreau
30ca20517a tools headers: Move the nolibc header from rcutorture to tools/include/nolibc/
As suggested by Ingo, this header file might benefit other tools than
just rcutorture. For now it's quite limited, but is easy to extend, so
exposing it into tools/include/nolibc/ will make it much easier to
adopt by other tools.

The mkinitrd.sh script in rcutorture was updated to use this new location.

Cc: Ingo Molnar <mingo@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-01-25 15:37:13 -08:00
Willy Tarreau
cc72a50994 rcutorture/nolibc: Add a bit of documentation to explain how to use nolibc
Ingo rightfully asked for a bit more documentation in the nolibc header,
so this patch adds some explanation about its purpose, how it's made, and
how to use it.

Cc: Ingo Molnar <mingo@kernel.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Reviewed-by: Joey Pabalinas <joeypabalinas@gmail.com>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
2019-01-25 15:37:13 -08:00
Willy Tarreau
85ebb12c4e rcutorture/nolibc: Fix some poor indentation and alignment
A few macros had their rightmost backslash misaligned, and the pollfd
struct definition resisted the previous code reindent. Nothing else
changed.

Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Reviewed-by: Joey Pabalinas <joeypabalinas@gmail.com>
2019-01-25 15:37:12 -08:00
Willy Tarreau
f90a66d685 rcutorture/nolibc: Fix the clobbered registers in the MIPS syscall definition
A last-minute checkpatch cleanup caused most of list of clobbered
registers to be lost in the MIPS syscall definition. Although this code
is not yet used on MIPS, it is nevertheless better to fix it before it
does get used.

Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-01-25 15:37:11 -08:00
Paul E. McKenney
0d8a9ea976 torture: Explain and simplify odd "for" loop in mkinitrd.sh
Why a Bourne-shell "for" loop?  And why 192 instances of "a"?  This commit
adds a shell comment to present the answer to these mysteries.  It also
uses a series of factor-of-four Bourne-shell assignments to make it
easy to see how many instances there are, replacing the earlier wall of
'a' characters.

Reported-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
[ paulmck: Fix wrong-variable bugs noted by Andrea Parri. ]
2019-01-25 15:37:09 -08:00
Paul E. McKenney
eaaf055f27 Merge branches 'bug.2018.11.12a', 'consolidate.2018.12.01a', 'doc.2018.11.12a', 'fixes.2018.11.12a', 'initrd.2018.11.08b', 'sil.2018.11.12a' and 'srcu.2018.11.27a' into HEAD
bug.2018.11.12a:  Get rid of BUG_ON() and friends
consolidate.2018.12.01a:  Continued RCU flavor-consolidation cleanup
doc.2018.11.12a:  Documentation updates
fixes.2018.11.12a:  Miscellaneous fixes
initrd.2018.11.08b:  Automate creation of rcutorture initrd
sil.2018.11.12a:  Remove more spin_unlock_wait() calls
2018-12-01 12:43:16 -08:00
Paul E. McKenney
df56e0f960 rcutorture/formal: Replace synchronize_sched() with synchronize_rcu()
Now that synchronize_rcu() waits for preempt-disable regions of code
as well as RCU read-side critical sections, synchronize_sched() can be
replaced by synchronize_rcu().  This commit therefore makes this change,
even though it is but a comment.

Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2018-12-01 12:38:52 -08:00
Willy Tarreau
b94ec36896 rcutorture: Make use of nolibc when available
This reduces the size of the init executable from ~800 kB to ~800 bytes
on x86_64. This is only implemented for x86_64, i386, arm and arm64.
Others not tested.

Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-11-08 21:52:55 -08:00
Willy Tarreau
66b6f755ad rcutorture: Import a copy of nolibc
This is a definition of the most common syscalls needed in minimalist
init executables, allowing to statically build them with no external
dependencies. It is sufficient in its current form to build rcutorture's
init on x86_64, i386, arm, and arm64. Others have not been ported or
tested. Updates may be found here :

     http://git.formilux.org/?p=people/willy/nolibc.git

Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-11-08 21:52:55 -08:00
Willy Tarreau
825fa4cdfb rcutorture: Check initrd/init instead of initrd only
If the build fails, we can end up with an empty initrd directory which
prevents the build script from operating again. Better rely on the
resulting init executable instead.

Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-11-08 21:52:55 -08:00
Willy Tarreau
18d7bf8ed3 rcutorture: Always strip using the cross-compiler
Strip using -s on the compiler command line instead of calling the "strip"
utility as the latter isn't necessarily compatible with the target arch.

Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-11-08 21:52:55 -08:00
Paul E. McKenney
70e9f50477 rcutorture: Add cross-compile capability to initrd.sh
This adds the CROSS_COMPILE environment to the initrd.sh script's
gcc command to enable cross compilation.

Reported-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-11-08 21:52:55 -08:00
Paul E. McKenney
229ab0cb5b rcutorture: Make initrd/init execute in userspace
Currently, the initrd/init script and executable remain blocked almost
all the time.  However, it is necessary to test nohz_full userspace
execution, which both variants of initrd/init fail to do.  This commit
therefore causes initrd/init to spend about a millisecond per second
executing in userspace.

Reported-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-11-08 21:52:55 -08:00
Paul E. McKenney
38e630424b rcutorture: Add initrd support for systems lacking dracut
The support for creating initrd directories using dracut is a great
improvement over having to always hand-create them, it is a bit annoying
to have to install some otherwise irrelevant package just to be able to
run rcutorture.  This commit therefore adds support for creating initrd
directories on systems innocent of dracut.  You do need gcc, but then
again you need that to build the kernel (or to build llvm) in any case.

The idea is to create an initrd directory containing nothing but a
statically linked binary having a for-loop over a long-term sleep().
The result is a Linux kernel with almost no userspace: even the
time-honored /dev, /lib, /tmp, and /usr directories are gone.  In fact,
the only directory present is "/", but only because I don't know how to
get rid of it, at least short of not having an initrd in the first place.
Although statically linked binaries are much maligned, and rightly so,
their disadvantages seem to be irrelevant for this particular use case.
From https://www.akkadia.org/drepper/no_static_linking.html:

1.	Fixes are difficult to apply to hordes of widely scattered
	statically linked binaries.  But in this case, there is only one
	binary, but there would otherwise be no fewer than four libraries.

2.	Security measures like local address randomization cannot be used.
	Prudence prevents me from asserting that it is impossible to
	base a remote attack on a networking-free rcutorture instance.
	Nevertheless, bonus points to the first person who comes up with
	such an attack!

3.	More efficient use of physical memory.  Not in this case, given
	that libc is 1.8MB and the statically linked binary "only" 800K.

4.	Features such as locales, name service switch (NSS),
	internationalized domain names (IDN) tool, and so on require
	dynamic linking.  Bonus points to the first person coming up
	with a valid rcutorture use case requiring these features in
	its initrd.

5.	Accidental violations of (L)GPL.  Actually, this change actually
	helps -avoid- such violations by reducing the temptation to
	pass around tarballs of rcutorture-ready initrd directories.
	After all, the rcutorture scripts automatically create an initrd
	directory for you, so why bother with the tarballs?

6.	Tools and hacks like ltrace, LD_PRELOAD, LD_PROFILE, and LD_AUDIT
	don't work.  Again, bonus points to the first person coming up
	with a valid rcutorture use case requiring these features in
	its initrd.

Nevertheless, the script will use dracut if available, and will create the
statically linked binary only when dracut are missing.  Those preferring
the smaller initrd directory resulting from the statically linked binary
(like me) are free to hand-edit mkinitrd.sh to remove the code using
dracut.  ;-)

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-11-08 21:52:55 -08:00
Connor Shu
8f15c682ac rcutorture: Automatically create initrd directory
The rcutorture scripts currently expect the user to create the
tools/testing/selftests/rcutorture/initrd directory.  Should the user
fail to do this, the kernel build will fail with obscure and confusing
error messages.  This commit therefore adds explicit checks for the
tools/testing/selftests/rcutorture/initrd directory, and if not present,
creates one on systems on which dracut is installed.  If this directory
could not be created, a less obscure error message is emitted and the
test is aborted.

Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Connor Shu <Connor.Shu@ibm.com>
[ paulmck: Adapt the script to fit into the rcutorture framework and
  severely abbreviate the initrd/init script. ]
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-11-08 21:52:55 -08:00
Paul E. McKenney
b56ada1209 Merge branches 'doc.2018.08.30a', 'dynticks.2018.08.30b', 'srcu.2018.08.30b' and 'torture.2018.08.29a' into HEAD
doc.2018.08.30a: Documentation updates
dynticks.2018.08.30b: RCU flavor consolidation updates and cleanups
srcu.2018.08.30b: SRCU updates
torture.2018.08.29a: Torture-test updates
2018-08-30 16:12:53 -07:00
Paul E. McKenney
55cda2290b rcutorture: Test early boot call_srcu()
Now that SRCU permits call_srcu() to be invoked at early boot, this
commit ensures that the rcutorture scripting tests early boot call_srcu().

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-08-30 16:10:38 -07:00
Paul E. McKenney
72ce30dd1f rcu: Stop testing RCU-bh and RCU-sched
Now that the RCU-bh and RCU-sched update-side functions are simple
wrappers around their RCU counterparts, there isn't a whole lot of
point in testing them.  This commit therefore removes the self-test
capability and removes the corresponding kernel-boot parameters.
It also updates the various rcutorture .boot files to remove the
kernel boot parameters that call for testing RCU-bh and RCU-sched.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-08-30 16:03:29 -07:00
Paul E. McKenney
a52d14addf rcutorture: Remove TREE06 and TREE08 from the default test list
Now that there is only one RCU flavor to rule them all, the TREE06
and TREE08 test scenarios are redundant.  This commit therefore removes
them.  Later changes will rebalance and renumber the tests.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-08-29 09:20:48 -07:00
Paul E. McKenney
31e7490741 torture: Stop overwriting Make.out file with obsolete version
The old approach placed all the build products into the b* directories,
which meant that some of these build products needed to be copied to
the proper directory in the res hierarchy.  The new approach leaves
things like .config and the .o files in the b1 directory, but directs
build output and diagnostics directly to the proper directory in the
res hierarchy.  Unfortunately, one of the copies was still carried out,
which could (and sometimes did) overwrite the build output and diagnostics
with obsolete output remaining in the b1 directory.

This commit therefore removes the offending "cp" command.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-08-29 09:20:48 -07:00
Paul E. McKenney
028be12b29 rcutorture: Change units of onoff_interval to jiffies
Some RCU bugs have been sensitive to the frequency of CPU-hotplug
operations, which have been gradually increased over time.  But this
frequency is now at the one-second lower limit that can be specified using
the rcutorture.onoff_interval kernel parameter.  This commit therefore
changes the units of rcutorture.onoff_interval from seconds to jiffies,
and also sets the value specified for this kernel parameter in the TREE03
rcutorture scenario to 200, which is 200 milliseconds for HZ=1000.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-07-12 15:42:01 -07:00
Paul E. McKenney
f34f2f5852 rcu: Move grace-period pre-init delay after pre-init
The main race with the early part of grace-period initialization appears
to be with CPU hotplug.  To more fully open this race window, this commit
moves the rcu_gp_slow() from the beginning of the early initialization
loop to follow that loop, thus widening the race window, especially for
the rcu_node structures that are initialized last.  This commit also
expands rcutree.gp_preinit_delay from 3 to 12, giving the same overall
delay in the grace period, but concentrated in the spot where it will
do the most good.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-07-12 15:39:06 -07:00
Paul E. McKenney
b4c1906f65 rcutorture: Make kvm-find-errors.sh find close calls
Although warnings about close calls are printed by kvm-recheck.sh,
kvm-find-errors.sh currently ignores them.  This could easily result
in someone failing to investigate close calls, so this commit makes
them visible to kvm-find-errors.sh.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-06-25 11:30:10 -07:00
Paul E. McKenney
69409750b2 rcutorture: Remove obsolete TREE08-T.boot file
The TREE08-T.boot file was used to provide alternative options for
debugging, but things have changed, it has not kept up, and it has not
been used or missed.  This commit therefore removes it.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-06-25 11:30:10 -07:00
Paul E. McKenney
5bfd7d34fe torture: Use a single build directory for torture scenarios
The torture scripting currently builds each kernel from a set of parallel
runs in its own build directory.  This can waste quite a bit of space when
running large numbers of concurrent scenarios, and pointlessly given that
the builds are run sequentially (albeit with a largish -j number passed to
"make").  This commit therefore places all build-command output in the
results directory, then does all builds in a single "b1" build directory.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-06-25 11:30:10 -07:00
Paul E. McKenney
da1a1e1923 torture: Make kvm-find-errors.sh find build warnings
Currently, kvm-find-errors.sh looks only for build errors ("error:"),
so this commit makes it also locate build warnings ("warning:").

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Nicholas Piggin <npiggin@gmail.com>
2018-05-15 10:32:25 -07:00
Paul E. McKenney
b4e8afbd21 rcutorture: Abbreviate kvm.sh summary lines
With the addition of the end-of-test state, it is not uncommon for the
kvm.sh summary lines to overflow 80 characters.  This commit therefore
applies abbreviations in order to make the line fit into 80 characters
with high probability.

And yes, I did make heavy use of punched cards back in the day, so 80
columns it is for my xterms!  ;-)

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Nicholas Piggin <npiggin@gmail.com>
2018-05-15 10:32:17 -07:00
Paul E. McKenney
413e5512bc rcutorture: Print end-of-test state in kvm.sh summary
This commit adds the end-of-test test, if present in the console output,
to the kvm.sh test summary that is printed by kvm-recheck.sh.  Note that
this only applies to rcutorture console output.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Nicholas Piggin <npiggin@gmail.com>
2018-05-15 10:32:13 -07:00
Paul E. McKenney
d600e06ba7 torture: Fold parse-torture.sh into parse-console.sh
The rcutorture scripting scans the console output twice, once to look
for various sorts of hangs and again to find warnings and panics.
Unfortunately, only the output of the second scan gets written to the
console.log.diags file, which can cause hangs to be overlooked.
This commit therefore folds the parse-torture.sh script (which looks
for hangs) into the parse-console.sh script (which looks for warnings
and panics).  This allows both types of failure information to be
added to console.log.diags, while still reliably removing this file
when it proves to be empty.

This also fixes a long-standing bug where rcuperf log files would
unconditionally complain about a hang.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Nicholas Piggin <npiggin@gmail.com>
2018-05-15 10:32:04 -07:00
Paul E. McKenney
95ce5f29e1 torture: Add a script to edit output from failed runs
This commit adds a script that allows viewing the build and/or
console output from failed rcutorture, locktorture, or rcuperf runs.
This replaces a time-honored but inefficient manual procedure that uses
cut and paste.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Nicholas Piggin <npiggin@gmail.com>
2018-05-15 10:31:52 -07:00
Paul E. McKenney
338c46403f Merge branches 'fixes.2018.02.23a', 'srcu.2018.02.20a' and 'torture.2018.02.20a' into HEAD
fixes.2018.02.23a: Miscellaneous fixes
srcu.2018.02.20a: SRCU updates
torture.2018.02.20a: Torture-test updates
2018-02-23 15:15:41 -08:00
Paul E. McKenney
85ba6bfe8b torture: Provide more sensible nreader/nwriter defaults for rcuperf
The default values for nreader and nwriter are apparently not all that
user-friendly, resulting in people doing scalability tests that ran all
runs at large scale.  This commit therefore makes both the nreaders and
nwriters module default to the number of CPUs, and adds a comment to
rcuperf.c stating that the number of CPUs should be specified using the
nr_cpus kernel boot parameter.  This commit also eliminates the redundant
rcuperf scripting specification of default values for these parameters.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-02-20 16:22:01 -08:00
Paul E. McKenney
0da8c08d71 torture: Grace periods do not piggyback off of themselves
The rcuperf trace-event processing counted every "done" trace event
as a piggyback, which is incorrect because the task that started the
grace period didn't piggyback at all.  This commit fixes this problem
by recording the task that started a given grace period and ignoring
that task's "done" record for that grace period.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-02-20 16:22:01 -08:00
Paul E. McKenney
cc839ce55d torture: Adjust rcuperf trace processing to allow for workqueues
The rcuperf event-trace processing assumes that expedited grace periods
start and end on the same task, an assumption that was violated by moving
expedited grace-period processing to workqueues.  This commit removes
this now-fallacious assumption from rcuperf's event-trace processing.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-02-20 16:22:00 -08:00
Paul E. McKenney
adcfe76c61 torture: Default jitter off when running rcuperf
The purpose of jitter is to expose concurrency bugs due to invalid
assumptions about forward progress.  There is usually little point
in jitter when measuring performance.  This commit therefore defaults
jitter off when running rcuperf.  You can override this by specifying
the kvm.sh "--jitter" argument -after- the "--torture rcuperf"
argument.  No idea why you would want this, but if you do, that is
how you do it.

One example of a conccurrency bug that this jitter might expose is one
in which the developer assumed that a given short region of code would be
guaranteed to execute within some short time limit.  Such assumptions are
invalid in virtualized environments because the hupervisor can preempt
the guest OS at any point, even when the guest OS thinks that it has
disabled interrupts.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-02-20 16:22:00 -08:00
Paul E. McKenney
642146b1ad torture: Specify qemu memory size with --memory argument
The 512 megabyte memory size has served quite well, but more memory
is required when using large trace buffers on large systems.  This
commit therefore adds a --memory argument to the kvm.sh script, which
allows the memory size to be specified on the command line, for example,
"--memory 768", --memory 800M", or "--memory 2G".

Reported-by: Sebastian Siewior <bigeasy@linutronix.de>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-02-20 16:21:59 -08:00
Lihao Liang
67ad71ddbc rcutorture: Add basic ARM64 support to run scripts
This commit adds support of the qemu command qemu-system-aarch64
to rcutorture.

Signed-off-by: Lihao Liang <lianglihao@huawei.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-02-20 16:21:59 -08:00
Paul E. McKenney
db92ca3ab8 rcutorture: Update kvm.sh header comment
The kvm.sh header comment is a bit of a relic, so this commit brings
it up to date.

Reported-by: Lihao Liang <lianglihao@huawei.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-02-20 16:21:58 -08:00
Lihao Liang
f4f2cf8bd8 doc: Fix typo in rcutorture documentation
Signed-off-by: Lihao Liang <lianglihao@huawei.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2018-02-20 16:10:19 -08:00
Paul E. McKenney
a7c8655b07 sched/isolation: Eliminate NO_HZ_FULL_ALL
Commit 6f1982fedd ("sched/isolation: Handle the nohz_full= parameter")
broke CONFIG_NO_HZ_FULL_ALL=y kernels.  This breakage is due to the code
under CONFIG_NO_HZ_FULL_ALL failing to invoke the shiny new housekeeping
functions.  This means that rcutorture scenario TREE04 now emits RCU CPU
stall warnings due to the RCU grace-period kthreads not being awakened
at a time of their choosing, or perhaps even not at all:

[   27.731422] rcu_bh kthread starved for 21001 jiffies! g18446744073709551369 c18446744073709551368 f0x0 RCU_GP_WAIT_FQS(3) ->state=0x402 ->cpu=3
[   27.731423] rcu_bh          I14936     9      2 0x80080000
[   27.731435] Call Trace:
[   27.731440]  __schedule+0x31a/0x6d0
[   27.731442]  schedule+0x31/0x80
[   27.731446]  schedule_timeout+0x15a/0x320
[   27.731453]  ? call_timer_fn+0x130/0x130
[   27.731457]  rcu_gp_kthread+0x66c/0xea0
[   27.731458]  ? rcu_gp_kthread+0x66c/0xea0

Because no one has complained about CONFIG_NO_HZ_FULL_ALL=y being broken,
I hypothesize that no one is in fact using it, other than rcutorture.
This commit therefore eliminates CONFIG_NO_HZ_FULL_ALL and updates
rcutorture's config files to instead use the nohz_full= kernel parameter
to put the desired CPUs into nohz_full mode.

Fixes: 6f1982fedd ("sched/isolation: Handle the nohz_full= parameter")

Reported-by: kernel test robot <xiaolong.ye@intel.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <frederic@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luiz Capitulino <lcapitulino@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Wanpeng Li <kernellwp@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Jonathan Corbet <corbet@lwn.net>
2018-02-15 15:40:37 -08:00
Paul E. McKenney
a2f2577d96 torture: Eliminate torture_runnable and perf_runnable
The purpose of torture_runnable is to allow rcutorture and locktorture
to be started and stopped via sysfs when they are built into the kernel
(as in not compiled as loadable modules).  However, the 0444 permissions
for both instances of torture_runnable prevent this use case from ever
being put into practice.  Given that there have been no complaints
about this deficiency, it is reasonable to conclude that no one actually
makes use of this sysfs capability.  The perf_runnable module parameter
for rcuperf is in the same situation.

This commit therefore removes both torture_runnable instances as well
as perf_runnable.

Reported-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2017-12-11 09:18:29 -08:00
SeongJae Park
af0695d3fc rcutorture/kvm-build.sh: Skip build directory check
Check for build-directory existence and write permissions are provided in
both 'kvm-test-1-run.sh' an 'kvm-build.sh'.  Because the 'kvm-build.sh'
is dependent on 'kvm-test-1-run.sh' ('kvm-build.sh' uses variables that
defined from its caller.), these checks are unnecessarily duplicated.
This commit therefore removes the check in from the 'kvm-build.sh' script.

Signed-off-by: SeongJae Park <sj38.park@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2017-12-11 09:18:27 -08:00
SeongJae Park
feef2d286a rcutorture: Simplify functions.sh include path
Inclusions of 'functions.sh' from 'kvm-test-1-run.sh' and
'kvm-recheck*.sh' use its absolute path.  Because the directory containing
'functions.sh' is already in PATH, the full path is unnecessary.  This
commit therefore simplifies the inclusions to use the short relative path.

Signed-off-by: SeongJae Park <sj38.park@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2017-12-11 09:18:26 -08:00
SeongJae Park
fa48beb5f4 rcutorture: Simplify logging
Both the 'kvm.sh' and 'kvm-test-1-run.sh' scripts log messages by printing
the message to 'stdout' and then also printing it into the log file.
Generation of the message thus occurs twice, once for 'stdout' and once
for the log file.  Moreover, many of the messages contain 'date' output,
which results in date being invoked twice (once for stdout print, once
for log file write).  As a result, the date information in stdout and
log file can differ, which could cause confusion.

This commit therefore simplifies the logging procedure by using 'tee'.

Signed-off-by: SeongJae Park <sj38.park@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2017-12-11 09:18:26 -08:00
SeongJae Park
81394e3f6d rcutorture/kvm-recheck-*: Improve result directory readability check
The kvm-recheck-(lock|rcu|rcuperf).sh scripts check whether the
user-specified results directory exists.  If not, it prints out error
message that says the specified directory is unreadable.  To make the
message more precise, this commit adds a readability check.

Fixes: 2193e1604e ("rcutorture: Abstract kvm-recheck.sh")

Signed-off-by: SeongJae Park <sj38.park@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2017-12-11 09:18:25 -08:00
SeongJae Park
512e3bd0b5 rcutorture/kvm.sh: Support execution from any directory
The 'kvm.sh' rcutorture script requires that it be invoked from the top
of Linux-kernel source tree.  It is just a subtle restriction, but users
using it for the first time could forget the restriction and be confused.
Moreover, it makes commands a little longer, which can be frustrating.
This commit therefore lets users invoke the script from any location.

Signed-off-by: SeongJae Park <sj38.park@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2017-12-11 09:18:25 -08:00