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  1. 02 12月, 2019 6 次提交
  3. 01 12月, 2019 4 次提交
  5. 30 11月, 2019 1 次提交
    • J
      io_uring: fix missing kmap() declaration on powerpc · aa4c3967
      由 Jens Axboe 提交于 
      Christophe reports that current master fails building on powerpc with
this error:

   CC      fs/io_uring.o
fs/io_uring.c: In function ‘loop_rw_iter’:
fs/io_uring.c:1628:21: error: implicit declaration of function ‘kmap’
[-Werror=implicit-function-declaration]
     iovec.iov_base = kmap(iter->bvec->bv_page)
                      ^
fs/io_uring.c:1628:19: warning: assignment makes pointer from integer
without a cast [-Wint-conversion]
     iovec.iov_base = kmap(iter->bvec->bv_page)
                    ^
fs/io_uring.c:1643:4: error: implicit declaration of function ‘kunmap’
[-Werror=implicit-function-declaration]
     kunmap(iter->bvec->bv_page);
     ^

which is caused by a missing highmem.h include. Fix it by including
it.

Fixes: 311ae9e1 ("io_uring: fix dead-hung for non-iter fixed rw")
Reported-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Tested-by: NChristophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: NJens Axboe <axboe@kernel.dk>
      aa4c3967
  7. 29 11月, 2019 1 次提交
  9. 28 11月, 2019 2 次提交
  11. 27 11月, 2019 8 次提交
    • J
      io_uring: make poll->wait dynamically allocated · e944475e
      由 Jens Axboe 提交于 
      In the quest to bring io_kiocb down to 3 cachelines, this one does
the trick. Make the wait_queue_entry for the poll command come out
of kmalloc instead of embedding it in struct io_poll_iocb, as the
latter is the largest member of io_kiocb. Once we trim this down a
bit, we're back at a healthy 192 bytes for struct io_kiocb.
Signed-off-by: NJens Axboe <axboe@kernel.dk>
      e944475e
    • J
      io-wq: shrink io_wq_work a bit · 6206f0e1
      由 Jens Axboe 提交于 
      Currently we're using 40 bytes for the io_wq_work structure, and 16 of
those is the doubly link list node. We don't need doubly linked lists,
we always add to tail to keep things ordered, and any other use case
is list traversal with deletion. For the deletion case, we can easily
support any node deletion by keeping track of the previous entry.

This shrinks io_wq_work to 32 bytes, and subsequently io_kiock from
io_uring to 216 to 208 bytes.
Signed-off-by: NJens Axboe <axboe@kernel.dk>
      6206f0e1
    • J
      io-wq: fix handling of NUMA node IDs · 3fc50ab5
      由 Jann Horn 提交于 
      There are several things that can go wrong in the current code on NUMA
systems, especially if not all nodes are online all the time:

 - If the identifiers of the online nodes do not form a single contiguous
   block starting at zero, wq->wqes will be too small, and OOB memory
   accesses will occur e.g. in the loop in io_wq_create().
 - If a node comes online between the call to num_online_nodes() and the
   for_each_node() loop in io_wq_create(), an OOB write will occur.
 - If a node comes online between io_wq_create() and io_wq_enqueue(), a
   lookup is performed for an element that doesn't exist, and an OOB read
   will probably occur.

Fix it by:

 - using nr_node_ids instead of num_online_nodes() for the allocation size;
   nr_node_ids is calculated by setup_nr_node_ids() to be bigger than the
   highest node ID that could possibly come online at some point, even if
   those nodes' identifiers are not a contiguous block
 - creating workers for all possible CPUs, not just all online ones

This is basically what the normal workqueue code also does, as far as I can
tell.
Signed-off-by: NJann Horn <jannh@google.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>
      3fc50ab5
    • J
      io_uring: use kzalloc instead of kcalloc for single-element allocations · ad6e005c
      由 Jann Horn 提交于 
      These allocations are single-element allocations, so don't use the array
allocation wrapper for them.
Signed-off-by: NJann Horn <jannh@google.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>
      ad6e005c
    • P
      io_uring: cleanup io_import_fixed() · 7d009165
      由 Pavel Begunkov 提交于 
      Clean io_import_fixed() call site and make it return proper type.
Signed-off-by: NPavel Begunkov <asml.silence@gmail.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>
      7d009165
    • P
      io_uring: inline struct sqe_submit · cf6fd4bd
      由 Pavel Begunkov 提交于 
      There is no point left in keeping struct sqe_submit. Inline it
into struct io_kiocb, so any req->submit.field is now just req->field

- moves initialisation of ring_file into io_get_req()
- removes duplicated req->sequence.
Signed-off-by: NPavel Begunkov <asml.silence@gmail.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>
      cf6fd4bd
    • P
      io_uring: store timeout's sqe->off in proper place · cc42e0ac
      由 Pavel Begunkov 提交于 
      Timeouts' sequence offset (i.e. sqe->off) is stored in
req->submit.sequence under a false name. Keep it in timeout.data
instead. The unused space for sequence will be reclaimed in the
following patches.
Signed-off-by: NPavel Begunkov <asml.silence@gmail.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>
      cc42e0ac
    • L
      Revert "vfs: properly and reliably lock f_pos in fdget_pos()" · 2be7d348
      由 Linus Torvalds 提交于 
      This reverts commit 0be0ee71.

I was hoping it would be benign to switch over entirely to FMODE_STREAM,
and we'd have just a couple of small fixups we'd need, but it looks like
we're not quite there yet.

While it worked fine on both my desktop and laptop, they are fairly
similar in other respects, and run mostly the same loads.  Kenneth
Crudup reports that it seems to break both his vmware installation and
the KDE upower service.  In both cases apparently leading to timeouts
due to waitinmg for the f_pos lock.

There are a number of character devices in particular that definitely
want stream-like behavior, but that currently don't get marked as
streams, and as a result get the exclusion between concurrent
read()/write() on the same file descriptor.  Which doesn't work well for
them.

The most obvious example if this is /dev/console and /dev/tty, which use
console_fops and tty_fops respectively (and ptmx_fops for the pty master
side).  It may be that it's just this that causes problems, but we
clearly weren't ready yet.

Because there's a number of other likely common cases that don't have
llseek implementations and would seem to act as stream devices:

  /dev/fuse		(fuse_dev_operations)
  /dev/mcelog		(mce_chrdev_ops)
  /dev/mei0		(mei_fops)
  /dev/net/tun		(tun_fops)
  /dev/nvme0		(nvme_dev_fops)
  /dev/tpm0		(tpm_fops)
  /proc/self/ns/mnt	(ns_file_operations)
  /dev/snd/pcm*		(snd_pcm_f_ops[])

and while some of these could be trivially automatically detected by the
vfs layer when the character device is opened by just noticing that they
have no read or write operations either, it often isn't that obvious.

Some character devices most definitely do use the file position, even if
they don't allow seeking: the firmware update code, for example, uses
simple_read_from_buffer() that does use f_pos, but doesn't allow seeking
back and forth.

We'll revisit this when there's a better way to detect the problem and
fix it (possibly with a coccinelle script to do more of the FMODE_STREAM
annotations).
Reported-by: NKenneth R. Crudup <kenny@panix.com>
Cc: Kirill Smelkov <kirr@nexedi.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      2be7d348
  13. 26 11月, 2019 18 次提交