only constraint that they have a lock cookie named mtx_lock.
This name, then, becames reserved from the struct that wants to use the
mtx(9) KPI and other locking primitives cannot reuse it for their
members.
Namely such structs are the current struct mtx and the new
struct mtx_padalign. The new structure will define an object which is
the same as the same layout of a struct mtx but will be allocated in
areas aligned to the cache line size and will be as big as a cache line.
This is supposed to give higher performance for highly contented mutexes
both spin or sleep (because of the adaptive spinning), where the cache
line contention results in too much traffic on the system bus.
The struct mtx_padalign can be used in a completely transparent way
with the mtx(9) KPI.
At the moment, a possibility to MFC the patch should be carefully
evaluated because this patch breaks the low level KPI
(not its representation though).
Discussed with: jhb
Reviewed by: jeff, andre
Reviewed by: mdf (earlier version)
Tested by: jimharris
in some very degenerate conditions.
However, until ath_rate_form_aggr() is taught to not form aggregates
if ANY selected rate is non-MCS, this can't yet be enabled.
So, just add a comment.
I've tried serialising TX using queues and such but unfortunately
due to how this interacts with the locking going on elsewhere in the
networking stack, the TX task gets delayed, resulting in quite a
noticable throughput loss:
* baseline TCP for 2x2 11n HT40 is ~ 170mbit/sec;
* TCP for TX task in the ath taskq, with the RX also going on - 80mbit/sec;
* TCP for TX task in a separate, second taskq - 100mbit/sec.
So for now I'm going with the Linux wireless stack approach - lock tx
early. The linux code does in the wireless stack, before the 802.11
state stuff happens and before it's punted to the driver.
But TX locking needs to also occur at the driver layer as the TX
completion code _also_ begins to drain the ifnet TX queue.
Whilst I'm here, add some KTR traces for the TX path.
Note:
* This really should be done at the net80211 layer (as well, at least.)
But that'll have to wait for a little more thought to happen.
- Change the code so that it relies on vfs_hash rather than on a
home-made hashtable.
- There's no need to inline fnv_32_buf().
Reviewed by: delphij
Tested by: pho
Sponsored by: iXsystems inc.
VM pressure. The reason is that in some codepaths pointers to stack
variables were passed from one thread to another.
In collaboration with: pho
Reported by: pho's stress2 suite
Sponsored by: iXsystems inc.
X86: fcmov doesn't handle all possible EFLAGS, fall back to a branch
for the others.
Otherwise it will try to use SSE patterns and fail horribly if sse is
disabled.
Fixes PR14035.
This should fix the following assertion failure:
Assertion failed: (Reg >= X86::FP0 && Reg <= X86::FP6 && "Expected FP
register!"), function getFPReg, file
contrib/llvm/lib/Target/X86/X86FloatingPoint.cpp, line 330.
which can show up when compiling contrib/compiler-rt, using -march=i686
through -march=pentium3 (CPU's which do support fcmov, but don't support
SSE2).
MFC after: 1 week
extended using growfs(8). The problem here is that geom_label checks if
the filesystem size recorded in UFS superblock is equal to the provider
(i.e. device) size. This check cannot be removed due to backward
compatibility. On the other hand, in most cases growfs(8) cannot set
fs_size in the superblock to match the provider size, because, differently
from newfs(8), it cannot recompute cylinder group sizes.
To fix this problem, add another superblock field, fs_providersize, used
only for this purpose. The geom_label(4) will attach if either fs_size
(filesystem created with newfs(8)) or fs_providersize (filesystem expanded
using growfs(8)) matches the device size.
PR: kern/165962
Reviewed by: mckusick
Sponsored by: FreeBSD Foundation
Previously atrun refused to run jobs if load average was not below fixed limit of 1.5.
PR: 173175
Reviewed by: peterj
Approved by: trasz (mentor)
MFC after: 2 weeks
to the initial SCSI INQUIRY command, enable all quirks.
This fixes detection of some Transcend TS2GUFM devices.
MFC after: 1 week
Reported by: Michael Dexter
executed. This means past the point where userret() is generally
executed.
Skip the td_pinned check if a callchain tracing is currently happening
and add a more robust check to pmc_capture_user_callchain() in order to
catch td_pinned leak past ast() in hwpmc case.
Reported and tested by: fabient
MFC after: 1 week
X-MFC: r240246
with the real value in regular way if sensing is supported. This fixes
minor inconsistency when playback redirection appeared in undefined state
on boot if headphones were not connected.
payload. This means driver has to split a TX buffer into two
pieces of TX buffers when the TX buffer contains both
ethernet/IP/TCP header and partial TCP payload. The controller
does not require all header should be in a TX buffer but driver
forced it to compute IP/TCP header size/offset which is required
parameter to configure DMA descriptor for TSO.
While here, slightly reorder DMA descriptor setup to enhance
readability and remove unnecessary code for TSO(upper stack never
requests TSO when the frame length is less than or equal to MTU).
Reported by: Yamagi Burmeister <lists <> yamagi dot org>
Tested by: Yamagi Burmeister <lists <> yamagi dot org>
MFC After: 1 week
Alike to BIO_WRITE, report success if at least one subdisk succeeded with
BIO_DELETE. But unlike BIO_WRITE don't fail disk on BIO_DELETE error.
Sponsored by: iXsystems, Inc.
MFC after: 1 month
If at least one subdisk in the volume supports it, BIO_DELETE requests
will be propagated down. Unfortunatelly, for RAID levels with redundancy
unmapped blocks will be mapped back during first rebuild/resync process.
Sponsored by: iXsystems, Inc.
MFC after: 1 month
(PowerMac12,1), which have a mac-io MPIC cell that indifies itself
as the root PIC despite the actual root PIC being on the northbridge.
No CPC945 systems have a mac-io PIC that does anything so just don't
attach on CPC945 (U4) systems.
MFC after: 3 days
and move that action from shutdown_pre_sync to shutdown_post_sync stage
to avoid extra flapping.
ZFS tends to not close devices on shutdown, that doesn't allow GEOM RAID
to shutdown gracefully. To handle that, mark volume as clean just when
shutdown time comes and there are no active writes.
MFC after: 2 weeks
Defer sending an independent window update if a delayed ACK is pending
saving a packet. The window update then gets piggy-backed on the next
already scheduled ACK.
Added grammar fixes as well.
MFC after: 2 weeks
