Back in 2008 we extended the capability bits from 32 to 64, and we did
it by extending the single 32-bit capability word from one word to an
array of two words. It was then obfuscated by hiding the "2" behind two
macro expansions, with the reasoning being that maybe it gets extended
further some day.
That reasoning may have been valid at the time, but the last thing we
want to do is to extend the capability set any more. And the array of
values not only causes source code oddities (with loops to deal with
it), but also results in worse code generation. It's a lose-lose
situation.
So just change the 'u32[2]' into a 'u64' and be done with it.
We still have to deal with the fact that the user space interface is
designed around an array of these 32-bit values, but that was the case
before too, since the array layouts were different (ie user space
doesn't use an array of 32-bit values for individual capability masks,
but an array of 32-bit slices of multiple masks).
So that marshalling of data is actually simplified too, even if it does
remain somewhat obscure and odd.
This was all triggered by my reaction to the new "cap_isidentical()"
introduced recently. By just using a saner data structure, it went from
unsigned __capi;
CAP_FOR_EACH_U32(__capi) {
if (a.cap[__capi] != b.cap[__capi])
return false;
}
return true;
to just being
return a.val == b.val;
instead. Which is rather more obvious both to humans and to compilers.
Cc: Mateusz Guzik <mjguzik@gmail.com>
Cc: Casey Schaufler <casey@schaufler-ca.com>
Cc: Serge Hallyn <serge@hallyn.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Paul Moore <paul@paul-moore.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
A previous commit split the hash table for polled requests into two
parts, but didn't get the fdinfo output updated. This means that it's
less useful for debugging, as we may think a given request is not pending
poll.
Fix this up by dumping the locked hash table contents too.
Fixes: 9ca9fb24d5 ("io_uring: mutex locked poll hashing")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
If we have doubly sized SQEs, then we need to shift the sq index by 1
to account for using two entries for a single request. The CQE dumping
gets this right, but the SQE one does not.
Improve the SQE dumping in general, the information dumped is pretty
sparse and doesn't even cover the whole basic part of the SQE. Include
information on the extended part of the SQE, if doubly sized SQEs are
in use. A typical dump now looks like the following:
[...]
SQEs: 32
32: opcode:URING_CMD, fd:0, flags:1, off:3225964160, addr:0x0, rw_flags:0x0, buf_index:0 user_data:2721, e0:0x0, e1:0xffffb8041000, e2:0x100000000000, e3:0x5500, e4:0x7, e5:0x0, e6:0x0, e7:0x0
33: opcode:URING_CMD, fd:0, flags:1, off:3225964160, addr:0x0, rw_flags:0x0, buf_index:0 user_data:2722, e0:0x0, e1:0xffffb8043000, e2:0x100000000000, e3:0x5508, e4:0x7, e5:0x0, e6:0x0, e7:0x0
34: opcode:URING_CMD, fd:0, flags:1, off:3225964160, addr:0x0, rw_flags:0x0, buf_index:0 user_data:2723, e0:0x0, e1:0xffffb8045000, e2:0x100000000000, e3:0x5510, e4:0x7, e5:0x0, e6:0x0, e7:0x0
[...]
Fixes: ebdeb7c01d ("io_uring: add support for 128-byte SQEs")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
We already have the cq_shift, just use that to tell if we have doubly
sized CQEs or not.
While in there, cleanup the CQE32 vs normal CQE size printing.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Commit 3a3d47fa9cfd ("io_uring: make io_uring_types.h public") moved
a bunch of io_uring types to a kernel wide header, so we could make
tracing a bit saner rather than pass in a ton of arguments.
However, there are a few types in there that are not really needed to
be system wide. Move the cancel data and mapped buffers back to the
appropriate io_uring local headers.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Add a new io_hash_bucket structure so that each bucket in cancel_hash
has separate spinlock. Use per entry lock for cancel_hash, this removes
some completion lock invocation and remove contension between different
cancel_hash entries.
Signed-off-by: Hao Xu <howeyxu@tencent.com>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/05d1e135b0c8bce9d1441e6346776589e5783e26.1655371007.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This also means moving a bit more of the fixed file handling to the
filetable side, which makes sense separately too.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Linus Torvalds
Jens Axboe
Pavel Begunkov
Hao Xu