Commit Graph

6920 Commits

Author SHA1 Message Date
Linus Torvalds
b0c79f49c3 Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 asm updates from Ingo Molnar:

 - Introduce the ORC unwinder, which can be enabled via
   CONFIG_ORC_UNWINDER=y.

   The ORC unwinder is a lightweight, Linux kernel specific debuginfo
   implementation, which aims to be DWARF done right for unwinding.
   Objtool is used to generate the ORC unwinder tables during build, so
   the data format is flexible and kernel internal: there's no
   dependency on debuginfo created by an external toolchain.

   The ORC unwinder is almost two orders of magnitude faster than the
   (out of tree) DWARF unwinder - which is important for perf call graph
   profiling. It is also significantly simpler and is coded defensively:
   there has not been a single ORC related kernel crash so far, even
   with early versions. (knock on wood!)

   But the main advantage is that enabling the ORC unwinder allows
   CONFIG_FRAME_POINTERS to be turned off - which speeds up the kernel
   measurably:

   With frame pointers disabled, GCC does not have to add frame pointer
   instrumentation code to every function in the kernel. The kernel's
   .text size decreases by about 3.2%, resulting in better cache
   utilization and fewer instructions executed, resulting in a broad
   kernel-wide speedup. Average speedup of system calls should be
   roughly in the 1-3% range - measurements by Mel Gorman [1] have shown
   a speedup of 5-10% for some function execution intense workloads.

   The main cost of the unwinder is that the unwinder data has to be
   stored in RAM: the memory cost is 2-4MB of RAM, depending on kernel
   config - which is a modest cost on modern x86 systems.

   Given how young the ORC unwinder code is it's not enabled by default
   - but given the performance advantages the plan is to eventually make
   it the default unwinder on x86.

   See Documentation/x86/orc-unwinder.txt for more details.

 - Remove lguest support: its intended role was that of a temporary
   proof of concept for virtualization, plus its removal will enable the
   reduction (removal) of the paravirt API as well, so Rusty agreed to
   its removal. (Juergen Gross)

 - Clean up and fix FSGS related functionality (Andy Lutomirski)

 - Clean up IO access APIs (Andy Shevchenko)

 - Enhance the symbol namespace (Jiri Slaby)

* 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (47 commits)
  objtool: Handle GCC stack pointer adjustment bug
  x86/entry/64: Use ENTRY() instead of ALIGN+GLOBAL for stub32_clone()
  x86/fpu/math-emu: Add ENDPROC to functions
  x86/boot/64: Extract efi_pe_entry() from startup_64()
  x86/boot/32: Extract efi_pe_entry() from startup_32()
  x86/lguest: Remove lguest support
  x86/paravirt/xen: Remove xen_patch()
  objtool: Fix objtool fallthrough detection with function padding
  x86/xen/64: Fix the reported SS and CS in SYSCALL
  objtool: Track DRAP separately from callee-saved registers
  objtool: Fix validate_branch() return codes
  x86: Clarify/fix no-op barriers for text_poke_bp()
  x86/switch_to/64: Rewrite FS/GS switching yet again to fix AMD CPUs
  selftests/x86/fsgsbase: Test selectors 1, 2, and 3
  x86/fsgsbase/64: Report FSBASE and GSBASE correctly in core dumps
  x86/fsgsbase/64: Fully initialize FS and GS state in start_thread_common
  x86/asm: Fix UNWIND_HINT_REGS macro for older binutils
  x86/asm/32: Fix regs_get_register() on segment registers
  x86/xen/64: Rearrange the SYSCALL entries
  x86/asm/32: Remove a bunch of '& 0xffff' from pt_regs segment reads
  ...
2017-09-04 09:52:57 -07:00
Ingo Molnar
edc2988c54 Merge branch 'linus' into locking/core, to fix up conflicts
Conflicts:
	mm/page_alloc.c

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-04 11:01:18 +02:00
Shaohua Li
bc75705d00 block/loop: remove unused field
nobody uses the list.

Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-09-01 13:57:35 -06:00
Shaohua Li
92d773324b block/loop: fix use after free
lo_rw_aio->call_read_iter->
1       aops->direct_IO
2       iov_iter_revert
lo_rw_aio_complete could happen between 1 and 2, the bio and bvec could
be freed before 2, which accesses bvec.

Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-09-01 13:57:33 -06:00
Shaohua Li
40326d8a33 block/loop: allow request merge for directio mode
Currently loop disables merge. While it makes sense for buffer IO mode,
directio mode can benefit from request merge. Without merge, loop could
send small size IO to underlayer disk and harm performance.

Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-09-01 08:44:34 -06:00
Shaohua Li
54bb0ade66 block/loop: set hw_sectors
Loop can handle any size of request. Limiting it to 255 sectors just
burns the CPU for bio split and request merge for underlayer disk and
also cause bad fs block allocation in directio mode.

Reviewed-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-09-01 08:44:32 -06:00
Linus Torvalds
501d9f7945 Merge branch 'for-linus' of git://git.kernel.dk/linux-block
Pull block fixes from Jens Axboe:
 "Unfortunately a few issues that warrant sending another pull request,
  even if I had hoped to avoid it. This contains:

   - A fix for multiqueue xen-blkback, on tear down / disconnect.

   - A few fixups for NVMe, including a wrong bit definition, fix for
     host memory buffers, and an nvme rdma page size fix"

* 'for-linus' of git://git.kernel.dk/linux-block:
  nvme: fix the definition of the doorbell buffer config support bit
  nvme-pci: use dma memory for the host memory buffer descriptors
  nvme-rdma: default MR page size to 4k
  xen-blkback: stop blkback thread of every queue in xen_blkif_disconnect
2017-08-31 18:42:21 -07:00
Omar Sandoval
43cade803e loop: fold loop_switch() into callers
The comments here are really outdated, and blk-mq made flushing much
simpler, so just fold the two cases into the callers.

Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-31 13:51:16 -06:00
Omar Sandoval
89e4fdecb5 loop: add ioctl for changing logical block size
This is a different approach from the first attempt in f2c6df7dbf
("loop: support 4k physical blocksize"). Rather than extending
LOOP_{GET,SET}_STATUS, add a separate ioctl just for setting the block
size.

Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-31 13:51:14 -06:00
Omar Sandoval
6c6b6f28b3 loop: set physical block size to PAGE_SIZE
The physical block size is "the lowest possible sector size that the
hardware can operate on without reverting to read-modify-write
operations" (from the comment on blk_queue_physical_block_size()). Since
loop does buffered I/O on the backing file by default, the RMW unit is a
page. This isn't the case for direct I/O mode, but let's keep it simple.

Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-31 13:51:12 -06:00
Omar Sandoval
8a0740c410 loop: get rid of lo_blocksize
This is only used for setting the soft block size on the struct
block_device once and then never used again.

Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-31 13:51:10 -06:00
NeilBrown
974c58566e drbd: remove BIOSET_NEED_RESCUER flag from drbd_{md_,}io_bio_set
Careful analysis shows that this flag is not needed.

The RESCUER flag is only needed when a make_request_fn might:
 - allocate a bio from the bioset
 - submit it with generic_make_request() or similar
 - allocate another bio from the bioset

The second allocation can block until the first bio is processed, so
a rescuer is needed to ensure the first bio does get processed.  With
a rescuer it will only get processed when the make_request_fn completes.

In drbd, allocations from drbd_io_bio_set happen from drbd_new_req()
or w_restart_disk_io() which is only called to handle
RESTART_FROZEN_DISK_IO.

In former is called precisely once from the make_request_fn.
The later is never called by within the make_request_fn.

So there cannot be two allocations in the same call to the
make_request_fn, so a rescuer is not needed.

Allocations from drbd_md_io_bio_set are used for IO to the bitmap and
the activity log.  There are only accessed from worker threads and
workqueues, never directly from make_request_fn.
Again, the rescuer isn't needed.

Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-30 08:10:02 -06:00
Philipp Reisner
5fc1efd5de drbd: Fix allyesconfig build, fix recent commit
Globals where prefixed with drbd_, that was missed in the
in #ifdef'nd code when it is built-in.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Fixes: 183ece3005 ("drbd: move global variables to drbd namespace and make some static")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-30 08:09:29 -06:00
Roland Kammerer
365cf663b6 drbd: switch from kmalloc() to kmalloc_array()
We had one call to kmalloc that actually allocates an array. Switch that
one to the kmalloc_array() function.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-29 15:34:46 -06:00
Roland Kammerer
d3d2948f43 drbd: abort drbd_start_resync if there is no connection
This was found by a static analysis tool. While highly unlikely, be sure
to return without dereferencing the NULL pointer.

Reported-by: Shaobo <shaobo@cs.utah.edu>
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-29 15:34:46 -06:00
Roland Kammerer
183ece3005 drbd: move global variables to drbd namespace and make some static
This is a follow-up to Gregs complaints that drbd clutteres the global
namespace.
Some of DRBD's module parameters are only used within one compilation
unit. Make these static.

Signed-off-by: Roland Kammerer <roland.kammerer@linbit.com>
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-29 15:34:46 -06:00
Greg Kroah-Hartman
8ab761e17e drbd: rename "usermode_helper" to "drbd_usermode_helper"
Nothing like having a very generic global variable in a tiny driver
subsystem to make a mess of the global namespace...

Note, there are many other "generic" named global variables in the drbd
subsystem, someone should fix those up one day before they hit a linking
error.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-29 15:34:46 -06:00
Lars Ellenberg
cde81d99af drbd: fix race between handshake and admin disconnect/down
conn_try_disconnect() could potentialy hit the BUG_ON()
in _conn_set_state() where it iterates over _drbd_set_state()
and "asserts" via BUG_ON() that the latter was successful.

If the STATE_SENT bit was not yet visible to conn_is_valid_transition()
early in _conn_request_state(), but became visible before conn_set_state()
later in that call path, we could hit the BUG_ON() after _drbd_set_state(),
because it returned SS_IN_TRANSIENT_STATE.

To avoid that race, we better protect set_bit(SENT_STATE) with the spinlock.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-29 15:34:46 -06:00
Lars Ellenberg
33d32fa712 drbd: fix potential deadlock when trying to detach during handshake
When requesting a detach, we first suspend IO, and also inhibit meta-data IO
by means of drbd_md_get_buffer(), because we don't want to "fail" the disk
while there is IO in-flight: the transition into D_FAILED for detach purposes
may get misinterpreted as actual IO error in a confused endio function.

We wrap it all into wait_event(), to retry in case the drbd_req_state()
returns SS_IN_TRANSIENT_STATE, as it does for example during an ongoing
connection handshake.

In that example, the receiver thread may need to grab drbd_md_get_buffer()
during the handshake to make progress.  To avoid potential deadlock with
detach, detach needs to grab and release the meta data buffer inside of
that wait_event retry loop. To avoid lock inversion between
mutex_lock(&device->state_mutex) and drbd_md_get_buffer(device),
introduce a new enum chg_state_flag CS_INHIBIT_MD_IO, and move the
call to drbd_md_get_buffer() inside the state_mutex grabbed in
drbd_req_state().

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-29 15:34:45 -06:00
Markus Elfring
427fd2bee0 drbd: A single dot should be put into a sequence.
Thus use the corresponding function "seq_putc".

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Roland Kammerer <roland.kammerer@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-29 15:34:45 -06:00
Lars Ellenberg
3f1a1b7cbb drbd: fix rmmod cleanup, remove _all_ debugfs entries
If there are still resources defined, but "empty", no more volumes
or connections configured, they don't hold module reference counts,
so rmmod is possible.

To avoid DRBD leftovers in debugfs, we need to call our global
drbd_debugfs_cleanup() only after all resources have been cleaned up.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-29 15:34:45 -06:00
Geliang Tang
be7445a381 drbd: Use setup_timer() instead of init_timer() to simplify the code.
Signed-off-by: Geliang Tang <geliangtang@gmail.com>
Signed-off-by: Roland Kammerer <roland.kammerer@linbit.com>
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-29 15:34:45 -06:00
Lars Ellenberg
7c752ed325 drbd: fix potential get_ldev/put_ldev refcount imbalance during attach
Race:

drbd_adm_attach()               | async drbd_md_endio()
                                |
device->ldev is still NULL.     |
                                |
drbd_md_read(                   |
 .endio = drbd_md_endio;        |
 submit;                        |
 ....                           |
 wait for done == 1;            |       done = 1;
);                              |       wake_up();
.. lot of other stuff,          |
.. includeing taking and        |
...giving up locks,             |
.. doing further IO,            |
.. stuff that takes "some time" |
                                | while in this context,
                                | this is the next statement.
                                | which means this context was scheduled
.. only then, finally,          | away for "some time".
device->ldev = nbc;             |
                                |       if (device->ldev)
                                |               put_ldev()

Unlikely, but possible. I was able to provoke it "reliably"
by adding an mdelay(500); after the wake_up().
Fixed by moving the if (!NULL) put_ldev() before done = 1;

Impact of the bug was that the resulting refcount imbalance
could lead to premature destruction of the object, potentially
causing a NULL pointer dereference during a subsequent detach.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-29 15:34:45 -06:00
Lars Ellenberg
9de7e14a1a drbd: new disk-option disable-write-same
Some backend devices claim to support write-same,
but would fail actual write-same requests.

Allow to set (or toggle) whether or not DRBD tries to support write-same.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-29 15:34:44 -06:00
Philipp Reisner
c200d98687 drbd: Fix resource role for newly created resources in events2
The conn_higest_role() (a terribly misnamed function) returns
the role of the resource. It returned R_UNKNOWN as long as the
resource has not a single device.

Resources without devices are short living objects.

But it matters for the NOTIFY_CREATE netwlink message. It makes
a lot more sense to report R_SECONDARY for the newly created
resource than R_UNKNOWN.

I reviewd all call sites of conn_highest_role(), that change
does not matter for the other call sites.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-29 15:34:44 -06:00
Baoyou Xie
1ffa7bfab4 drbd: mark symbols static where possible
We get a few warnings when building kernel with W=1:
drbd/drbd_receiver.c:1224:6: warning: no previous prototype for 'one_flush_endio' [-Wmissing-prototypes]
drbd/drbd_req.c:1450:6: warning: no previous prototype for 'send_and_submit_pending' [-Wmissing-prototypes]
drbd/drbd_main.c:924:6: warning: no previous prototype for 'assign_p_sizes_qlim' [-Wmissing-prototypes]
....

In fact, these functions are only used in the file in which they are
declared and don't need a declaration, but can be made static.
So this patch marks these functions with 'static'.

Signed-off-by: Baoyou Xie <baoyou.xie@linaro.org>
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-29 15:34:44 -06:00
Lars Ellenberg
e1fbc4ca9d drbd: Send P_NEG_ACK upon write error in protocol != C
In protocol != C, we forgot to send the P_NEG_ACK for failing writes.

Once we no longer submit to local disk, because we already "detached",
due to the typical "on-io-error detach;" config setting,
we already send the neg acks right away.

Only those requests that have been submitted,
and have been error-completed by the local disk,
would forget to send the neg-ack,
and only in asynchronous replication (protocol != C).
Unless this happened during resync,
where we already always send acks, regardless of protocol.

The primary side needs the P_NEG_ACK in order to mark
the affected block(s) for resync in its out-of-sync bitmap.

If the blocks in question are not re-written again,
we may miss to resync them later, causing data inconsistencies.

This patch will always send the neg-acks, and also at least try to
persist the out-of-sync status on the local node already.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-29 15:34:44 -06:00
Lars Ellenberg
de6978be44 drbd: add explicit plugging when submitting batches
When submitting batches of requests which had been queued on the
submitter thread, typically because they needed to wait for an
activity log transactions, use explicit plugging to help potential
merging of requests in the backend io-scheduler.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-29 15:34:44 -06:00
Lars Ellenberg
9da10e8da3 drbd: change list_for_each_safe to while(list_first_entry_or_null)
Two instances of list_for_each_safe can drop their tmp element, they
really just peel off each element in turn from the start of the list.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-29 15:34:44 -06:00
Lars Ellenberg
c51a0ef374 drbd: introduce drbd_recv_header_maybe_unplug
Recently, drbd_recv_header() was changed to potentially
implicitly "unplug" the backend device(s), in case there
is currently nothing to receive.

Be more explicit about it: re-introduce the original drbd_recv_header(),
and introduce a new drbd_recv_header_maybe_unplug() for use by the
receiver "main loop".

Using explicit plugging via blk_start_plug(); blk_finish_plug();
really helps the io-scheduler of the backend with merging requests.

Wrap the receiver "main loop" with such a plug.
Also catch unplug events on the Primary,
and try to propagate.

This is performance relevant.  Without this, if the receiving side does
not merge requests, number of IOPS on the peer can me significantly
higher than IOPS on the Primary, and can easily become the bottleneck.

Together, both changes should help to reduce the number of IOPS
as seen on the backend of the receiving side, by increasing
the chance of merging mergable requests, without trading latency
for more throughput.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-29 15:34:43 -06:00
Bart Van Assche
6fd5b91dab skd: Let the block layer core choose .nr_requests
Since blk_mq_init_queue() initializes .nr_requests to the tag set
size and since that value is a good default for the skd driver, do
not overwrite the value set by blk_mq_init_queue(). This change
doubles the default value of .nr_requests.

Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-29 09:43:06 -06:00
Bart Van Assche
bf231981be skd: Remove blk_queue_bounce_limit() call
Since sTec s1120 devices support 64-bit DMA it is not necessary
to request data buffer bouncing. Hence remove the
blk_queue_bounce_limit() call.

Suggested-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-29 09:43:03 -06:00
Jens Axboe
015a2f823e Merge branch 'stable/for-jens-4.13' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen into for-linus
Pull xen-blkback fix from Konrad:

"[...] A bug-fix when shutting down xen block backend driver with
 multiple queues and the driver not clearing all of them."
2017-08-29 08:32:58 -06:00
Ying Huang
966a967116 smp: Avoid using two cache lines for struct call_single_data
struct call_single_data is used in IPIs to transfer information between
CPUs.  Its size is bigger than sizeof(unsigned long) and less than
cache line size.  Currently it is not allocated with any explicit alignment
requirements.  This makes it possible for allocated call_single_data to
cross two cache lines, which results in double the number of the cache lines
that need to be transferred among CPUs.

This can be fixed by requiring call_single_data to be aligned with the
size of call_single_data. Currently the size of call_single_data is the
power of 2.  If we add new fields to call_single_data, we may need to
add padding to make sure the size of new definition is the power of 2
as well.

Fortunately, this is enforced by GCC, which will report bad sizes.

To set alignment requirements of call_single_data to the size of
call_single_data, a struct definition and a typedef is used.

To test the effect of the patch, I used the vm-scalability multiple
thread swap test case (swap-w-seq-mt).  The test will create multiple
threads and each thread will eat memory until all RAM and part of swap
is used, so that huge number of IPIs are triggered when unmapping
memory.  In the test, the throughput of memory writing improves ~5%
compared with misaligned call_single_data, because of faster IPIs.

Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Huang, Ying <ying.huang@intel.com>
[ Add call_single_data_t and align with size of call_single_data. ]
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Aaron Lu <aaron.lu@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/87bmnqd6lz.fsf@yhuang-mobile.sh.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-29 15:14:38 +02:00
Bhumika Goyal
dfbde55249 nbd: make device_attribute const
Make this const as is is only passed as an argument to the
function device_create_file and device_remove_file and the corresponding
arguments are of type const.
Done using Coccinelle

Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-28 15:21:27 -06:00
Jens Axboe
b3c3051220 null_blk: use available 'dev' in nullb_device_power_store()
We already have this pointer, no need to use to_nullb_device()
again.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-28 15:06:31 -06:00
Shaohua Li
060fd198a3 block/nullb: delete unnecessary memory free
Commit 2984c86(nullb: factor disk parameters) has a typo. The
nullb_device allocation/free is done outside of null_add_dev. The commit
accidentally frees the nullb_device in error code path.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-28 15:06:17 -06:00
Jens Axboe
cd996fb47c Merge tag 'v4.13-rc7' into for-4.14/block-postmerge
Linux 4.13-rc7

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-28 13:00:44 -06:00
Linus Torvalds
17e34c4fd0 Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost
Pull virtio fixes from Michael Tsirkin:
 "Fixes two obvious bugs in virtio pci"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  virtio_pci: fix cpu affinity support
  virtio_blk: fix incorrect message when disk is resized
2017-08-25 17:40:03 -07:00
Bart Van Assche
f5cb2d5152 skd: Remove SKD_ID_INCR
The SKD_ID_INCR flag in skd_request_context.id duplicates information
that is already available otherwise, e.g. through the block layer
request state and through skd_request_context.state. Hence remove
the code that manipulates this flag and also the flag itself.
Since skd_isr_completion_posted() only uses the lower bits of
skd_request_context.id as hardware tag, this patch does not change
the behavior of the skd driver. I'm referring to the following code:

    tag = req_id & SKD_ID_SLOT_AND_TABLE_MASK;

Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-25 15:29:45 -06:00
Bart Van Assche
4633504c1a skd: Make it easier for static analyzers to analyze skd_free_disk()
Although it is easy to see that skdev->disk != NULL if skdev->queue
!= NULL, add a test for skdev->disk to avoid that smatch reports the
following warning:

drivers/block/skd_main.c:3080 skd_free_disk()
         error: we previously assumed 'disk' could be null (see line 3074)

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-25 15:29:43 -06:00
Bart Van Assche
795bc1b542 skd: Inline skd_end_request()
It is not worth to keep the debug statements in skd_end_request().
Without debug statements that function only consists of two
statements. Hence inline skd_end_request().

Suggested-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-25 15:29:42 -06:00
Bart Van Assche
296cb94c9d skd: Rename skd_softirq_done() into skd_complete_rq()
The latter name follows more closely the function names used in
other blk-mq drivers.

Suggested-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-25 15:29:40 -06:00
Shaohua Li
0d06a42f79 block/nullb: fix NULL dereference
Dan reported this:

The patch 2984c8684f: "nullb: factor disk parameters" from Aug 14,
2017, leads to the following Smatch complaint:

drivers/block/null_blk.c:1759 null_init_tag_set()
	 error: we previously assumed 'nullb' could be null (see line
1750)

  1755		set->cmd_size	= sizeof(struct nullb_cmd);
  1756		set->flags = BLK_MQ_F_SHOULD_MERGE;
  1757		set->driver_data = NULL;
  1758
  1759		if (nullb->dev->blocking)
                    ^^^^^^^^^^^^^^^^^^^^
And an unchecked dereference.

nullb could be NULL here.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-25 14:52:01 -06:00
Annie Li
dc52d783d6 xen-blkback: stop blkback thread of every queue in xen_blkif_disconnect
In xen_blkif_disconnect, before checking inflight I/O, following code
stops the blkback thread,
if (ring->xenblkd) {
	kthread_stop(ring->xenblkd);
	wake_up(&ring->shutdown_wq);
}
If there is inflight I/O in any non-last queue, blkback returns -EBUSY
directly, and above code would not be called to stop thread of remaining
queue and processs them. When removing vbd device with lots of disk I/O
load, some queues with inflight I/O still have blkback thread running even
though the corresponding vbd device or guest is gone.
And this could cause some problems, for example, if the backend device type
is file, some loop devices and blkback thread always lingers there forever
after guest is destroyed, and this causes failure of umounting repositories
unless rebooting the dom0.
This patch allows thread of every queue has the chance to get stopped.
Otherwise, only thread of queue previous to(including) first busy one get
stopped, blkthread of remaining queue will still run.  So stop all threads
properly and return -EBUSY if any queue has inflight I/O.

Signed-off-by: Annie Li <annie.li@oracle.com>
Reviewed-by: Herbert van den Bergh <herbert.van.den.bergh@oracle.com>
Reviewed-by: Bhavesh Davda <bhavesh.davda@oracle.com>
Reviewed-by: Adnan Misherfi <adnan.misherfi@oracle.com>
Acked-by: Roger Pau Monné <roger.pau@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2017-08-25 15:59:34 -04:00
Jens Axboe
231b3db18d null_blk: update email adress
Update to a working one, the fusionio address hasn't been valid
in 4 years.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-25 12:53:15 -06:00
Stefan Hajnoczi
1046d30490 virtio_blk: fix incorrect message when disk is resized
The message printed on disk resize is incorrect.  The following is
printed when resizing to 2 GiB:

  $ truncate -s 1G test.img
  $ qemu -device virtio-blk-pci,logical_block_size=4096,...
  (qemu) block_resize drive1 2G

  virtio_blk virtio0: new size: 4194304 4096-byte logical blocks (17.2 GB/16.0 GiB)

The virtio_blk capacity config field is in 512-byte sector units
regardless of logical_block_size as per the VIRTIO specification.
Therefore the message should read:

  virtio_blk virtio0: new size: 524288 4096-byte logical blocks (2.15 GB/2.0 GiB)

Note that this only affects the printed message.  Thankfully the actual
block device has the correct size because the block layer expects
capacity in sectors.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-08-25 21:37:15 +03:00
Hannes Reinecke
253d2464df scsi: cciss: Drop obsolete driver
The hpsa driver now has support for all boards the cciss driver
used to support, so this patch removes the cciss driver and
make hpsa an alias to cciss.

Signed-off-by: Hannes Reinecke <hare@suse.com>
Acked-by: Don Brace <don.brace@microsemi.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-08-24 22:28:57 -04:00
Juergen Gross
ecda85e702 x86/lguest: Remove lguest support
Lguest seems to be rather unused these days. It has seen only patches
ensuring it still builds the last two years and its official state is
"Odd Fixes".

Remove it in order to be able to clean up the paravirt code.

Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: boris.ostrovsky@oracle.com
Cc: lguest@lists.ozlabs.org
Cc: rusty@rustcorp.com.au
Cc: xen-devel@lists.xenproject.org
Link: http://lkml.kernel.org/r/20170816173157.8633-3-jgross@suse.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-24 09:57:28 +02:00
Omar Sandoval
1e6ec9ea89 Revert "loop: support 4k physical blocksize"
There's some stuff still up in the air, let's not get stuck with a
subpar ABI. I'll follow up with something better for 4.14.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-23 15:57:55 -06:00