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Without a full memory barrier between the store to the flags and the
load of the SQ tail the two operations can be reordered and this can
lead to a situation where the SQPOLL thread goes to sleep while the
application writes to the SQ tail and doesn't see the wakeup flag.
This memory barrier pairs with a full memory barrier in the application
between its store to the SQ tail and its load of the flags.
Signed-off-by: Almog Khaikin <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jens Axboe <[email protected]>
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Ensure that we call fsnotify_modify() if we write a file, and that we
do fsnotify_access() if we read it. This enables anyone using inotify
on the file to get notified.
Ditto for fallocate, ensure that fsnotify_modify() is called.
Cc: [email protected]
Signed-off-by: Jens Axboe <[email protected]>
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We currently have a race where we recycle the selected buffer if poll
returns IO_APOLL_OK. But that's too late, as the poll could already be
triggering or have triggered. If that race happens, then we're putting a
buffer that's already being used.
Fix this by recycling before we arm poll. This does mean that we'll
sometimes almost instantly re-select the buffer, but it's rare enough in
testing that it should not pose a performance issue.
Fixes: b1c62645758e ("io_uring: recycle provided buffers if request goes async")
Signed-off-by: Jens Axboe <[email protected]>
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The fix for not advancing the iterator if we're using fixed buffers is
broken in that it can hit a condition where we don't terminate the loop.
This results in io-wq looping forever, asking to read (or write) 0 bytes
for every subsequent loop.
Reported-by: Joel Jaeschke <[email protected]>
Link: https://github.com/axboe/liburing/issues/549
Fixes: 16c8d2df7ec0 ("io_uring: ensure symmetry in handling iter types in loop_rw_iter()")
Signed-off-by: Jens Axboe <[email protected]>
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Looks like a victim of too much copy/paste, we should not be looking
at req->open.how in accept. The point is to check CLOEXEC and error
out, which we don't invalid direct descriptors on exec. Hence any
attempt to get a direct descriptor with CLOEXEC is invalid.
No harm is done here, as req->open.how.flags overlaps with
req->accept.flags, but it's very confusing and might change if either of
those command structs are modified.
Fixes: aaa4db12ef7b ("io_uring: accept directly into fixed file table")
Signed-off-by: Jens Axboe <[email protected]>
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Workloads using provided buffers benefit from using and returning buffers
in the right order, and so does TLBs for that matter. Manage the internal
buffer list in a straight list, rather than use the head buffer as the
insertion node. Use a hashed list for the buffer group IDs instead of
xarray, the overhead is much lower this way. xarray provides internal
locking and other trickery that is handy for some uses cases, but
io_uring already locks internally for the buffer manipulation and needs
none of that.
This is good for about a 2% reduction in overhead, combination of the
improved management and the fact that the workload has an easier time
bundling back provided buffers.
Signed-off-by: Jens Axboe <[email protected]>
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Add ->has_evfd flag, which is true IFF there is an eventfd attached, and
use it to hide io_eventfd_signal() into __io_commit_cqring_flush() and
combine fast checks in a single if. Also, gcc 11.2 wasn't inlining
io_cqring_ev_posted() without this change, so helps with that as well.
Signed-off-by: Pavel Begunkov <[email protected]>
Link: https://lore.kernel.org/r/f6168471997decded475a063f92915787975a30b.1647481208.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <[email protected]>
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io_commit_cqring() is currently always under spinlock section, so it's
always better to keep it as slim as possible. Move
__io_commit_cqring_flush() out of it into ev_posted*(). If fast checks
do fail and this post-processing is required, we'll reacquire
->completion_lock, which is fine as we don't care about performance of
draining and offset timeouts.
Signed-off-by: Pavel Begunkov <[email protected]>
Link: https://lore.kernel.org/r/ec4e81fd720d3bc7bca8cb9152e080dad1a052f1.1647481208.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <[email protected]>
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A preparation patch, which moves a fast ->io_ev_fd check out of
io_eventfd_signal() into ev_posted*(). Compilers are smart enough for it
to not change anything, but will need it later.
Signed-off-by: Pavel Begunkov <[email protected]>
Link: https://lore.kernel.org/r/ec4091ac76d43912b73917e8db651c2dac4b7b01.1647481208.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <[email protected]>
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smp_mb() in io_cqring_ev_posted_iopoll() is only there because of
waitqueue_active(). However, non-SQPOLL IOPOLL ring doesn't wake the CQ
and so the barrier there is useless. Kill it, it's usually pretty
expensive.
Signed-off-by: Pavel Begunkov <[email protected]>
Link: https://lore.kernel.org/r/d72e8ef6f7a3f6a72e18fad8409f7d47afc8da7d.1647481208.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <[email protected]>
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Use io_req_complete_failed() in kiocb_done(). This cleans up the code,
but also ensures that a provided buffers is correctly freed on failure.
Signed-off-by: Pavel Begunkov <[email protected]>
Link: https://lore.kernel.org/r/a4880106fcf199d5810707fe2d17126fcdf18bc4.1647481208.git.asml.silence@gmail.com
[axboe: split from previous patch]
Signed-off-by: Jens Axboe <[email protected]>
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It's never a good idea to put provided buffers without notifying the
userspace, it'll lead to userspace leaks, so add io_put_kbuf() in
io_req_complete_failed(). The fail helper is called by all sorts of
requests, but it's still safe to do as io_put_kbuf() will return 0 in
for all requests that don't support and so don't expect provided buffers.
Signed-off-by: Pavel Begunkov <[email protected]>
Link: https://lore.kernel.org/r/a4880106fcf199d5810707fe2d17126fcdf18bc4.1647481208.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <[email protected]>
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io_fill_cqe*() is not always the best way to post CQEs just because
there is enough of infrastructure on top. Replace a raw call to a
variant of it inside of io_timeout_cancel(), which also saves us some
bloating and might help with batching later.
Signed-off-by: Pavel Begunkov <[email protected]>
Link: https://lore.kernel.org/r/46113ec4345764b4aef3b384ce38cceabaeedcbb.1647481208.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <[email protected]>
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Restore consistency in __io_fill_cqe* like helpers, always honouring
"io_" prefix and adding "req" when we're passing in a request.
Signed-off-by: Pavel Begunkov <[email protected]>
Link: https://lore.kernel.org/r/bd016ff5c1a4f74687828069d2619d8a65e0c6d7.1647481208.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <[email protected]>
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With commit "io_uring: cache req->apoll->events in req->cflags" applied,
we now have just io_poll_remove_entries() dipping into req->apoll when
it isn't strictly necessary.
Mark poll and double-poll with a flag, so we know if we need to look
at apoll->double_poll. This avoids pulling in those cachelines if we
don't need them. The common case is that the poll wake handler already
removed these entries while hot off the completion path.
Signed-off-by: Jens Axboe <[email protected]>
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When we arm poll on behalf of a different type of request, like a network
receive, then we allocate req->apoll as our poll entry. Running network
workloads shows io_poll_check_events() as the most expensive part of
io_uring, and it's all due to having to pull in req->apoll instead of
just the request which we have hot already.
Cache poll->events in req->cflags, which isn't used until the request
completes anyway. This isn't strictly needed for regular poll, where
req->poll.events is used and thus already hot, but for the sake of
unification we do it all around.
This saves 3-4% of overhead in certain request workloads.
Signed-off-by: Jens Axboe <[email protected]>
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This serves two purposes:
- We now have the last cacheline mostly unused for generic workloads,
instead of having to pull in the poll refs explicitly for workloads
that rely on poll arming.
- It shrinks the io_kiocb from 232 to 224 bytes.
Signed-off-by: Jens Axboe <[email protected]>
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Make the tracing formatting for user_data and flags consistent.
Having consistent formatting allows one for example to grep for a specific
user_data/flags and be able to trace a single sqe through easily.
Change user_data to 0x%llx and flags to 0x%x everywhere. The '0x' is
useful to disambiguate for example "user_data 100".
Additionally remove the '=' for flags in io_uring_req_failed, again for consistency.
Signed-off-by: Dylan Yudaken <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jens Axboe <[email protected]>
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Particularly for networked workloads, io_uring intensively uses its
poll based backend to get a notification when data/space is available.
Profiling workloads, we see 3-4% of alloc+free that is directly attributed
to just the apoll allocation and free (and the rest being skb alloc+free).
For the fast path, we have ctx->uring_lock held already for both issue
and the inline completions, and we can utilize that to avoid any extra
locking needed to have a basic recycling cache for the apoll entries on
both the alloc and free side.
Double poll still requires an allocation. But those are rare and not
a fast path item.
With the simple cache in place, we see a 3-4% reduction in overhead for
the workload.
Signed-off-by: Jens Axboe <[email protected]>
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Julia and the kernel test robot report that the prep handling for this
command inadvertently checks one field twice:
fs/io_uring.c:4338:42-56: duplicated argument to && or ||
Get rid of it.
Reported-by: kernel test robot <[email protected]>
Reported-by: Julia Lawall <[email protected]>
Fixes: 4f57f06ce218 ("io_uring: add support for IORING_OP_MSG_RING command")
Signed-off-by: Jens Axboe <[email protected]>
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By default, io_uring will stop submitting a batch of requests if we run
into an error submitting a request. This isn't strictly necessary, as
the error result is passed out-of-band via a CQE anyway. And it can be
a bit confusing for some applications.
Provide a way to setup a ring that will continue submitting on error,
when the error CQE has been posted.
There's still one case that will break out of submission. If we fail
allocating a request, then we'll still return -ENOMEM. We could in theory
post a CQE for that condition too even if we never got a request. Leave
that for a potential followup.
Reported-by: Dylan Yudaken <[email protected]>
Signed-off-by: Jens Axboe <[email protected]>
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If we are using provided buffers, it's less than useful to have a buffer
selected and pinned if a request needs to go async or arms poll for
notification trigger on when we can process it.
Recycle the buffer in those events, so we don't pin it for the duration
of the request.
Signed-off-by: Jens Axboe <[email protected]>
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If we drop buffers between scheduling a retry, then we need to re-import
when we start the request again.
Signed-off-by: Jens Axboe <[email protected]>
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Most of the logic in io_read() deals with regular files, and in some ways
it would make sense to split the handling into S_IFREG and others. But
at least for retry, we don't need to bother setting up a bunch of state
just to abort in the loop later. In particular, don't bother forcing
setup of async data for a normal non-vectored read when we don't need it.
Signed-off-by: Jens Axboe <[email protected]>
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The sqpoll thread can be used for performing the napi busy poll in a
similar way that it does io polling for file systems supporting direct
access bypassing the page cache.
The other way that io_uring can be used for napi busy poll is by
calling io_uring_enter() to get events.
If the user specify a timeout value, it is distributed between polling
and sleeping by using the systemwide setting
/proc/sys/net/core/busy_poll.
The changes have been tested with this program:
https://github.com/lano1106/io_uring_udp_ping
and the result is:
Without sqpoll:
NAPI busy loop disabled:
rtt min/avg/max/mdev = 40.631/42.050/58.667/1.547 us
NAPI busy loop enabled:
rtt min/avg/max/mdev = 30.619/31.753/61.433/1.456 us
With sqpoll:
NAPI busy loop disabled:
rtt min/avg/max/mdev = 42.087/44.438/59.508/1.533 us
NAPI busy loop enabled:
rtt min/avg/max/mdev = 35.779/37.347/52.201/0.924 us
Co-developed-by: Hao Xu <[email protected]>
Signed-off-by: Hao Xu <[email protected]>
Signed-off-by: Olivier Langlois <[email protected]>
Link: https://lore.kernel.org/r/810bd9408ffc510ff08269e78dca9df4af0b9e4e.1646777484.git.olivier@trillion01.com
Signed-off-by: Jens Axboe <[email protected]>
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Move up the block manipulating the sig variable to execute code
that may encounter an error and exit first before continuing
executing the rest of the function and avoid useless computations
Signed-off-by: Olivier Langlois <[email protected]>
Link: https://lore.kernel.org/r/84513f7cc1b1fb31d8f4cb910aee033391d036b4.1646777484.git.olivier@trillion01.com
Signed-off-by: Jens Axboe <[email protected]>
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This adds support for IORING_OP_MSG_RING, which allows an SQE to signal
another ring. That allows either waking up someone waiting on the ring,
or even passing a 64-bit value via the user_data field in the CQE.
sqe->fd must contain the fd of a ring that should receive the CQE.
sqe->off will be propagated to the cqe->user_data on the target ring,
and sqe->len will be propagated to cqe->res. The results CQE will have
IORING_CQE_F_MSG set in its flags, to indicate that this CQE was generated
from a messaging request rather than a SQE issued locally on that ring.
This effectively allows passing a 64-bit and a 32-bit quantify between
the two rings.
This request type has the following request specific error cases:
- -EBADFD. Set if the sqe->fd doesn't point to a file descriptor that is
of the io_uring type.
- -EOVERFLOW. Set if we were not able to deliver a request to the target
ring.
Signed-off-by: Jens Axboe <[email protected]>
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In testing high frequency workloads with provided buffers, we spend a
lot of time in allocating and freeing the buffer units themselves.
Rather than repeatedly free and alloc them, add a recycling cache
instead. There are two caches:
- ctx->io_buffers_cache. This is the one we grab from in the submission
path, and it's protected by ctx->uring_lock. For inline completions,
we can recycle straight back to this cache and not need any extra
locking.
- ctx->io_buffers_comp. If we're not under uring_lock, then we use this
list to recycle buffers. It's protected by the completion_lock.
On adding a new buffer, check io_buffers_cache. If it's empty, check if
we can splice entries from the io_buffers_comp_cache.
This reduces about 5-10% of overhead from provided buffers, bringing it
pretty close to the non-provided path.
Signed-off-by: Jens Axboe <[email protected]>
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Lots of workloads use multiple threads, in which case the file table is
shared between them. This makes getting and putting the ring file
descriptor for each io_uring_enter(2) system call more expensive, as it
involves an atomic get and put for each call.
Similarly to how we allow registering normal file descriptors to avoid
this overhead, add support for an io_uring_register(2) API that allows
to register the ring fds themselves:
1) IORING_REGISTER_RING_FDS - takes an array of io_uring_rsrc_update
structs, and registers them with the task.
2) IORING_UNREGISTER_RING_FDS - takes an array of io_uring_src_update
structs, and unregisters them.
When a ring fd is registered, it is internally represented by an offset.
This offset is returned to the application, and the application then
uses this offset and sets IORING_ENTER_REGISTERED_RING for the
io_uring_enter(2) system call. This works just like using a registered
file descriptor, rather than a real one, in an SQE, where
IOSQE_FIXED_FILE gets set to tell io_uring that we're using an internal
offset/descriptor rather than a real file descriptor.
In initial testing, this provides a nice bump in performance for
threaded applications in real world cases where the batch count (eg
number of requests submitted per io_uring_enter(2) invocation) is low.
In a microbenchmark, submitting NOP requests, we see the following
increases in performance:
Requests per syscall Baseline Registered Increase
----------------------------------------------------------------
1 ~7030K ~8080K +15%
2 ~13120K ~14800K +13%
4 ~22740K ~25300K +11%
Co-developed-by: Xiaoguang Wang <[email protected]>
Signed-off-by: Jens Axboe <[email protected]>
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Fix incorrect name reference in comment. ki_filp does not exist in the
struct, but file does.
Signed-off-by: Dylan Yudaken <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jens Axboe <[email protected]>
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There is a slight optimisation to be had by calculating the correct pos
pointer inside io_kiocb_update_pos and then using that later.
It seems code size drops by a bit:
000000000000a1b0 0000000000000400 t io_read
000000000000a5b0 0000000000000319 t io_write
vs
000000000000a1b0 00000000000003f6 t io_read
000000000000a5b0 0000000000000310 t io_write
Signed-off-by: Dylan Yudaken <[email protected]>
Reviewed-by: Pavel Begunkov <[email protected]>
Signed-off-by: Jens Axboe <[email protected]>
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Update kiocb->ki_pos at execution time rather than in io_prep_rw().
io_prep_rw() happens before the job is enqueued to a worker and so the
offset might be read multiple times before being executed once.
Ensures that the file position in a set of _linked_ SQEs will be only
obtained after earlier SQEs have completed, and so will include their
incremented file position.
Signed-off-by: Dylan Yudaken <[email protected]>
Reviewed-by: Pavel Begunkov <[email protected]>
Signed-off-by: Jens Axboe <[email protected]>
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io_kiocb_ppos is called in both branches, and it seems that the compiler
does not fuse this. Fusing removes a few bytes from loop_rw_iter.
Before:
$ nm -S fs/io_uring.o | grep loop_rw_iter
0000000000002430 0000000000000124 t loop_rw_iter
After:
$ nm -S fs/io_uring.o | grep loop_rw_iter
0000000000002430 000000000000010d t loop_rw_iter
Signed-off-by: Dylan Yudaken <[email protected]>
Reviewed-by: Pavel Begunkov <[email protected]>
Signed-off-by: Jens Axboe <[email protected]>
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Avoid testing TIF_NOTIFY_SIGNAL twice by calling task_sigpending()
directly from io_run_task_work_sig()
Signed-off-by: Olivier Langlois <[email protected]>
Link: https://lore.kernel.org/r/bd7c0495f7656e803e5736708591bb665e6eaacd.1645041650.git.olivier@trillion01.com
Signed-off-by: Jens Axboe <[email protected]>
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This makes the io-uring tracepoints consistent. Where it makes sense
the tracepoints start with the following four fields:
- context (ring)
- request
- user_data
- opcode.
Signed-off-by: Stefan Roesch <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jens Axboe <[email protected]>
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This introduces the __fill_cqe function. This is necessary
to correctly issue the io_uring_complete tracepoint.
Signed-off-by: Stefan Roesch <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jens Axboe <[email protected]>
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It's better to use the defined enum stuff not the hardcoded number to
define array.
Signed-off-by: Hao Xu <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jens Axboe <[email protected]>
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reduce acct->lock lock and unlock in different functions to make the
code clearer.
Signed-off-by: Hao Xu <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jens Axboe <[email protected]>
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wqe->lock is abused, it now protects acct->work_list, hash stuff,
nr_workers, wqe->free_list and so on. Lets first get the work_list out
of the wqe-lock mess by introduce a specific lock for work list. This
is the first step to solve the huge contension between work insertion
and work consumption.
good thing:
- split locking for bound and unbound work list
- reduce contension between work_list visit and (worker's)free_list.
For the hash stuff, since there won't be a work with same file in both
bound and unbound work list, thus they won't visit same hash entry. it
works well to use the new lock to protect hash stuff.
Results:
set max_unbound_worker = 4, test with echo-server:
nice -n -15 ./io_uring_echo_server -p 8081 -f -n 1000 -l 16
(-n connection, -l workload)
before this patch:
Samples: 2M of event 'cycles:ppp', Event count (approx.): 1239982111074
Overhead Command Shared Object Symbol
28.59% iou-wrk-10021 [kernel.vmlinux] [k] native_queued_spin_lock_slowpath
8.89% io_uring_echo_s [kernel.vmlinux] [k] native_queued_spin_lock_slowpath
6.20% iou-wrk-10021 [kernel.vmlinux] [k] _raw_spin_lock
2.45% io_uring_echo_s [kernel.vmlinux] [k] io_prep_async_work
2.36% iou-wrk-10021 [kernel.vmlinux] [k] _raw_spin_lock_irqsave
2.29% iou-wrk-10021 [kernel.vmlinux] [k] io_worker_handle_work
1.29% io_uring_echo_s [kernel.vmlinux] [k] io_wqe_enqueue
1.06% iou-wrk-10021 [kernel.vmlinux] [k] io_wqe_worker
1.06% io_uring_echo_s [kernel.vmlinux] [k] _raw_spin_lock
1.03% iou-wrk-10021 [kernel.vmlinux] [k] __schedule
0.99% iou-wrk-10021 [kernel.vmlinux] [k] tcp_sendmsg_locked
with this patch:
Samples: 1M of event 'cycles:ppp', Event count (approx.): 708446691943
Overhead Command Shared Object Symbol
16.86% iou-wrk-10893 [kernel.vmlinux] [k] native_queued_spin_lock_slowpat
9.10% iou-wrk-10893 [kernel.vmlinux] [k] _raw_spin_lock
4.53% io_uring_echo_s [kernel.vmlinux] [k] native_queued_spin_lock_slowpat
2.87% iou-wrk-10893 [kernel.vmlinux] [k] io_worker_handle_work
2.57% iou-wrk-10893 [kernel.vmlinux] [k] _raw_spin_lock_irqsave
2.56% io_uring_echo_s [kernel.vmlinux] [k] io_prep_async_work
1.82% io_uring_echo_s [kernel.vmlinux] [k] _raw_spin_lock
1.33% iou-wrk-10893 [kernel.vmlinux] [k] io_wqe_worker
1.26% io_uring_echo_s [kernel.vmlinux] [k] try_to_wake_up
spin_lock failure from 25.59% + 8.89% = 34.48% to 16.86% + 4.53% = 21.39%
TPS is similar, while cpu usage is from almost 400% to 350%
Signed-off-by: Hao Xu <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jens Axboe <[email protected]>
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Clang warns:
fs/io_uring.c:9396:9: warning: variable 'ret' is uninitialized when used here [-Wuninitialized]
return ret;
^~~
fs/io_uring.c:9373:13: note: initialize the variable 'ret' to silence this warning
int fd, ret;
^
= 0
1 warning generated.
Just return 0 directly and reduce the scope of ret to the if statement,
as that is the only place that it is used, which is how the function was
before the fixes commit.
Fixes: 1a75fac9a0f9 ("io_uring: avoid ring quiesce while registering/unregistering eventfd")
Link: https://github.com/ClangBuiltLinux/linux/issues/1579
Signed-off-by: Nathan Chancellor <[email protected]>
Reviewed-by: Nick Desaulniers <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jens Axboe <[email protected]>
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None of the opcodes in io_uring_register use ring quiesce anymore. Hence
io_register_op_must_quiesce always returns false and io_ctx_quiesce is
never called.
Signed-off-by: Usama Arif <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jens Axboe <[email protected]>
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IORING_SETUP_R_DISABLED prevents submitting requests and so there will be
no requests until IORING_REGISTER_ENABLE_RINGS is called. And
IORING_REGISTER_RESTRICTIONS works only before
IORING_REGISTER_ENABLE_RINGS is called. Hence ring quiesce is not needed
for these opcodes.
Signed-off-by: Usama Arif <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jens Axboe <[email protected]>
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This is done using the RCU data structure (io_ev_fd). eventfd_async is
moved from io_ring_ctx to io_ev_fd which is RCU protected hence avoiding
ring quiesce which is much more expensive than an RCU lock. The place
where eventfd_async is read is already under rcu_read_lock so there is no
extra RCU read-side critical section needed.
Signed-off-by: Usama Arif <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jens Axboe <[email protected]>
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This is done by creating a new RCU data structure (io_ev_fd) as part of
io_ring_ctx that holds the eventfd_ctx.
The function io_eventfd_signal is executed under rcu_read_lock with a
single rcu_dereference to io_ev_fd so that if another thread unregisters
the eventfd while io_eventfd_signal is still being executed, the
eventfd_signal for which io_eventfd_signal was called completes
successfully.
The process of registering/unregistering eventfd is already done under
uring_lock so multiple threads won't enter a race condition while
registering/unregistering eventfd.
With the above approach ring quiesce can be avoided which is much more
expensive then using RCU lock. On the system tested, io_uring_register
with IORING_REGISTER_EVENTFD takes less than 1ms with RCU lock, compared
to 15ms before with ring quiesce.
Signed-off-by: Usama Arif <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
[axboe: long line fixups]
Signed-off-by: Jens Axboe <[email protected]>
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The information on whether eventfd is registered is not very useful and
would result in the tracepoint being enclosed in an rcu_readlock in a
later patch that tries to avoid ring quiesce for registering eventfd.
Suggested-by: Jens Axboe <[email protected]>
Signed-off-by: Usama Arif <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jens Axboe <[email protected]>
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git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
Pull btrfs fixes from David Sterba:
"A few more fixes for various problems that have user visible effects
or seem to be urgent:
- fix corruption when combining DIO and non-blocking io_uring over
multiple extents (seen on MariaDB)
- fix relocation crash due to premature return from commit
- fix quota deadlock between rescan and qgroup removal
- fix item data bounds checks in tree-checker (found on a fuzzed
image)
- fix fsync of prealloc extents after EOF
- add missing run of delayed items after unlink during log replay
- don't start relocation until snapshot drop is finished
- fix reversed condition for subpage writers locking
- fix warning on page error"
* tag 'for-5.17-rc6-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
btrfs: fallback to blocking mode when doing async dio over multiple extents
btrfs: add missing run of delayed items after unlink during log replay
btrfs: qgroup: fix deadlock between rescan worker and remove qgroup
btrfs: fix relocation crash due to premature return from btrfs_commit_transaction()
btrfs: do not start relocation until in progress drops are done
btrfs: tree-checker: use u64 for item data end to avoid overflow
btrfs: do not WARN_ON() if we have PageError set
btrfs: fix lost prealloc extents beyond eof after full fsync
btrfs: subpage: fix a wrong check on subpage->writers
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Pull kvm fixes from Paolo Bonzini:
"x86 guest:
- Tweaks to the paravirtualization code, to avoid using them when
they're pointless or harmful
x86 host:
- Fix for SRCU lockdep splat
- Brown paper bag fix for the propagation of errno"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: x86: pull kvm->srcu read-side to kvm_arch_vcpu_ioctl_run
KVM: x86/mmu: Passing up the error state of mmu_alloc_shadow_roots()
KVM: x86: Yield to IPI target vCPU only if it is busy
x86/kvmclock: Fix Hyper-V Isolated VM's boot issue when vCPUs > 64
x86/kvm: Don't waste memory if kvmclock is disabled
x86/kvm: Don't use PV TLB/yield when mwait is advertised
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git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc fix from Michael Ellerman:
"Fix build failure when CONFIG_PPC_64S_HASH_MMU is not set.
Thanks to Murilo Opsfelder Araujo, and Erhard F"
* tag 'powerpc-5.17-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/64s: Fix build failure when CONFIG_PPC_64S_HASH_MMU is not set
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git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fixes from Steven Rostedt:
- Fix sorting on old "cpu" value in histograms
- Fix return value of __setup() boot parameter handlers
* tag 'trace-v5.17-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing: Fix return value of __setup handlers
tracing/histogram: Fix sorting on old "cpu" value
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