commit 75dbb685f4 upstream.
request_reinit() is not only ugly as the comment rightfully suggests,
but also unsafe. Even though it is called with osdc->lock held for
write in all cases, resetting the OSD request refcount can still race
with handle_reply() and result in use-after-free. Taking linger ping
as an example:
handle_timeout thread handle_reply thread
down_read(&osdc->lock)
req = lookup_request(...)
...
finish_request(req) # unregisters
up_read(&osdc->lock)
__complete_request(req)
linger_ping_cb(req)
# req->r_kref == 2 because handle_reply still holds its ref
down_write(&osdc->lock)
send_linger_ping(lreq)
req = lreq->ping_req # same req
# cancel_linger_request is NOT
# called - handle_reply already
# unregistered
request_reinit(req)
WARN_ON(req->r_kref != 1) # fires
request_init(req)
kref_init(req->r_kref)
# req->r_kref == 1 after kref_init
ceph_osdc_put_request(req)
kref_put(req->r_kref)
# req->r_kref == 0 after kref_put, req is freed
<further req initialization/use> !!!
This happens because send_linger_ping() always (re)uses the same OSD
request for watch ping requests, relying on cancel_linger_request() to
unregister it from the OSD client and rip its messages out from the
messenger. send_linger() does the same for watch/notify registration
and watch reconnect requests. Unfortunately cancel_request() doesn't
guarantee that after it returns the OSD client would be completely done
with the OSD request -- a ref could still be held and the callback (if
specified) could still be invoked too.
The original motivation for request_reinit() was inability to deal with
allocation failures in send_linger() and send_linger_ping(). Switching
to using osdc->req_mempool (currently only used by CephFS) respects that
and allows us to get rid of request_reinit().
Cc: stable@vger.kernel.org
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Xiubo Li <xiubli@redhat.com>
Acked-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Replace a global map->crush_workspace (protected by a global mutex)
with a list of workspaces, up to the number of CPUs + 1.
This is based on a patch from Robin Geuze <robing@nl.team.blue>.
Robin and his team have observed a 10-20% increase in IOPS on all
queue depths and lower CPU usage as well on a high-end all-NVMe
100GbE cluster.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
When doing some testing recently, I hit some page allocation failures
on mount, when creating the wb_pagevec_pool for the mount. That
requires 128k (32 contiguous pages), and after thrashing the memory
during an xfstests run, sometimes that would fail.
128k for each mount seems like a lot to hold in reserve for a rainy
day, so let's change this to a global mempool that gets allocated
when the module is plugged in.
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Drop duplicated words "down" and "the" in fs/ceph/.
[ idryomov: merge into a single patch ]
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
This will send the caps/read/write/metadata metrics to any available MDS
once per second, which will be the same as the userland client. It will
skip the MDS sessions which don't support the metric collection, as the
MDSs will close socket connections when they get an unknown type
message.
We can disable the metric sending via the disable_send_metrics module
parameter.
[ jlayton: fix up endianness bug in ceph_mdsc_send_metrics() ]
URL: https://tracker.ceph.com/issues/43215
Signed-off-by: Xiubo Li <xiubli@redhat.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
The caller can just ignore the return. No need for this wrapper that
just casts the other function to void.
[ idryomov: argument alignment ]
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
osd_req_flags is overly general and doesn't suit its only user
(read_from_replica option) well:
- applying osd_req_flags in account_request() affects all OSD
requests, including linger (i.e. watch and notify). However,
linger requests should always go to the primary even though
some of them are reads (e.g. notify has side effects but it
is a read because it doesn't result in mutation on the OSDs).
- calls to class methods that are reads are allowed to go to
the replica, but most such calls issued for "rbd map" and/or
exclusive lock transitions are requested to be resent to the
primary via EAGAIN, doubling the latency.
Get rid of global osd_req_flags and set read_from_replica flag
only on specific OSD requests instead.
Fixes: 8ad44d5e0d ("libceph: read_from_replica option")
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Allow indicating future I/O pattern via flags. This is supported since
Kraken (and bluestore persists flags together with expected_object_size
and expected_write_size).
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Jason Dillaman <dillaman@redhat.com>
Expose replica reads through read_from_replica=balance and
read_from_replica=localize. The default is to read from primary
(read_from_replica=no).
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
OSD-side issues with reads from replica have been resolved in
Octopus. Reading from replica should be safe wrt. unstable or
uncommitted state now, so add support for balanced and localized
reads.
There are two cases when a read from replica can't be served:
- OSD may silently drop the request, expecting the client to
notice that the acting set has changed and resend via the usual
means (handled with t->used_replica)
- OSD may return EAGAIN, expecting the client to resend to the
primary, ignoring replica read flags (see handle_reply())
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Allow expressing client's location in terms of CRUSH hierarchy as
a set of (bucket type name, bucket name) pairs. The userspace syntax
"crush_location = key1=value1 key2=value2" is incompatible with mount
options and needed adaptation. Key-value pairs are separated by '|'
and we use ':' instead of '=' to separate keys from values. So for:
crush_location = host=foo rack=bar
one would write:
crush_location=host:foo|rack:bar
As in userspace, "multipath" locations are supported, so indicating
locality for parallel hierarchies is possible:
crush_location=rack:foo1|rack:foo2|datacenter:bar
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Needed for the next commit and useful for ceph_pg_pool_info tree as
well. I'm leaving the asserting helper in for now, but we should look
at getting rid of it in the future.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
sizeof(flexible-array-member) triggers a warning because flexible array
members have incomplete type[1]. There are some instances of code in
which the sizeof operator is being incorrectly/erroneously applied to
zero-length arrays and the result is zero. Such instances may be hiding
some bugs. So, this work (flexible-array member conversions) will also
help to get completely rid of those sorts of issues.
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Calculate the latency for OSD read requests. Add a new r_end_stamp
field to struct ceph_osd_request that will hold the time of that
the reply was received. Use that to calculate the RTT for each call,
and divide the sum of those by number of calls to get averate RTT.
Keep a tally of RTT for OSD writes and number of calls to track average
latency of OSD writes.
URL: https://tracker.ceph.com/issues/43215
Signed-off-by: Xiubo Li <xiubli@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Add i_last_rd and i_last_wr to ceph_inode_info. These fields are
used to track the last time the client acquired read/write caps for
the inode.
If there is no read/write on an inode for 'caps_wanted_delay_max'
seconds, __ceph_caps_file_wanted() does not request caps for read/write
even there are open files.
Call __ceph_touch_fmode() for dir operations. __ceph_caps_file_wanted()
calculates dir's wanted caps according to last dir read/modification. If
there is recent dir read, dir inode wants CEPH_CAP_ANY_SHARED caps. If
there is recent dir modification, also wants CEPH_CAP_FILE_EXCL.
Readdir is a special case. Dir inode wants CEPH_CAP_FILE_EXCL after
readdir, as with that, modifications do not need to release
CEPH_CAP_FILE_SHARED or invalidate all dentry leases issued by readdir.
Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
With the Octopus release, the MDS will hand out directory create caps.
If we have Fxc caps on the directory, and complete directory information
or a known negative dentry, then we can return without waiting on the
reply, allowing the open() call to return very quickly to userland.
We use the normal ceph_fill_inode() routine to fill in the inode, so we
have to gin up some reply inode information with what we'd expect the
newly-created inode to have. The client assumes that it has a full set
of caps on the new inode, and that the MDS will revoke them when there
is conflicting access.
This functionality is gated on the wsync/nowsync mount options.
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Track and correctly handle directory caps for asynchronous operations.
Add aliases for Frc caps that we now designate at Dcu caps (when dealing
with directories).
Unlike file caps, we don't reclaim these when the session goes away, and
instead preemptively release them. In-flight async dirops are instead
handled during reconnect phase. The client needs to re-do a synchronous
operation in order to re-get directory caps.
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Newer versions of the MDS will flag a dentry as "primary". In later
patches, we'll need to consult this info, so track it in di->flags.
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
...and ensure that such requests are never queued. The MDS has need to
know that a request is asynchronous so add flags and proper
infrastructure for that.
Also, delegated inode numbers and directory caps are associated with the
session, so ensure that async requests are always transmitted on the
first attempt and are never queued to wait for session reestablishment.
If it does end up looking like we'll need to queue the request, then
have it return -EJUKEBOX so the caller can reattempt with a synchronous
request.
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
On my machine (x86_64) this struct is 952 bytes, which gets rounded up
to 1024 by kmalloc. Move this to a dedicated slabcache, so we can
allocate them without the extra 72 bytes of overhead per.
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Since these helpers are only used by ceph.ko, move them there and
rename them with _sync_ qualifiers.
Signed-off-by: Xiubo Li <xiubli@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>