of the newer drivers. The basic problem was
that the driver was pulling the mbuf off the
drbr ring and then when sending with xmit(), encounting
a full transmit ring. Thus the lower layer
xmit() function would return an error, and the
drivers would then append the data back on to the ring.
For TCP this is a horrible scenario sure to bring
on a fast-retransmit.
The fix is to use drbr_peek() to pull the data pointer
but not remove it from the ring. If it fails then
we either call the new drbr_putback or drbr_advance
method. Advance moves it forward (we do this sometimes
when the xmit() function frees the mbuf). When
we succeed we always call advance. The
putback will always copy the mbuf back to the top
of the ring. Note that the putback *cannot* be used
with a drbr_dequeue() only with drbr_peek(). We most
of the time, in putback, would not need to copy it
back since most likey the mbuf is still the same, but
sometimes xmit() functions will change the mbuf via
a pullup or other call. So the optimial case for
the single consumer is to always copy it back. If
we ever do a multiple_consumer (for lagg?) we
will need a test and atomic in the put back possibly
a seperate putback_mc() in the ring buf.
Reviewed by: jhb@freebsd.org, jlv@freebsd.org
Posix requires that open(2) is restartable for SA_RESTART.
For non-posix objects, in particular, devfs nodes, still disable
automatic restart of the opens. The open call to a driver could have
significant side effects for the hardware.
Noted and reviewed by: jilles
Discussed with: bde
MFC after: 2 weeks
cpuset mask for the associated interrupt thread.
The text used above is verbatim from r195249 and the code should now be
in line with the intent of that commit.
195702, 195703, and 195821 prevented a thread from suspending while holding
locks inside of NFS by forcing the thread to fail sleeps with EINTR or
ERESTART but defer the thread suspension to the user boundary. However,
this had the effect that stopping a process during an NFS request could
abort the request and trigger EINTR errors that were visible to userland
processes (previously the thread would have suspended and completed the
request once it was resumed).
This change instead effectively masks stop signals while in the NFS client.
It uses the existing TDF_SBDRY flag to effect this since SIGSTOP cannot
be masked directly. Also, instead of setting PBDRY on individual sleeps,
the NFS client now sets the TDF_SBDRY flag around each NFS request and
stop signals are masked for all sleeps during that region (the previous
change missed sleeps in lockmgr locks). The end result is that stop
signals sent to threads performing an NFS request are completely
ignored until after the NFS request has finished processing and the
thread prepares to return to userland. This restores the behavior of
stop signals being transparent to userland processes while still
preventing threads from suspending while holding NFS locks.
Reviewed by: kib
MFC after: 1 month
using /dev/consolectl close. This fixes a problem where if
a USB mouse is detached while a button is pressed, that
button is never released.
MFC after: 1 week
- Add const quilifiers to fields that store value of __FILE__.
- Use long type for fields that store value of __LINE__.
- Sort and style(9) debugging fields.
- Add initializer for debugging fields into TAILQ_INITIALIZER macro.
PR: 175759
Submitted by: Andrey Simonenko <simon comsys.ntu-kpi.kiev.ua>
Reviewed by: bde
This eliminates the need to recompile the kernel when the default value
of NKPT is not big enough - for e.g. when loading large kernel modules
or memory disk images from the loader.
If NKPT is defined in the kernel configuration file then it overrides the
dynamic calculation.
Reviewed by: alc, kib
ISO/IEC 9899:1999 (E) 5.2.1p3 guarantees that the values of the characters
0123456789 are contiguous.
The generated syntax.c and syntax.h remain the same.
Submitted by: Christoph Mallon
requires 8 bytes alignment on RX buffer. Given that non-jumbo
frame works on any alignments I guess this DMA limitation for RX
buffer could be jumbo frame specific one. Also I'm not sure
whether this DMA limitation is related with 64bit DMA. Previously
age(4) disabled 64bit DMA addressing due to silent data corruption.
So we may need more testing on re-enabling 64bit DMA in future.
While I'm here, change mbuf chaining algorithm to use fixed sized
buffer and force software checksum if controller reports length
error. According to QAC, RFD is not updated at all for jumbo frame
so it works just like alc(4) controllers. This change also added
alignment fixup for strict alignment architectures. Because I'm
not aware of any non-x86 machines that use age(4) controllers it's
just for completeness at this moment.
Wit this change, jumbo frame should work with age(4).
Tested by: Christian Gusenbauer < c47g <> gmx dot at >
MFC after: 1 week
The check is copied from vnet_ng_ether_init.
Not sure if it covers all the types that we want to support with
ng_ether.
Reported by: markj
Discussed with: zec
MFC after: 10 days
X-MFC with: r246245
