On Mon, 02 Feb 2009, Hartmut wrote:
This change set is wrong. The affected functions cannot be called from
an interrupt context, because they may process large buffers. In this
case, interrupts are disabled for a long time. Functions, like
dvb_dmx_swfilter_packets(), could be called only from a tasklet.
This change set does hide some strong design bugs in dm1105.c and
au0828-dvb.c.
Please revert this change set and do fix the bugs in dm1105.c and
au0828-dvb.c (and other files).
On Sun, 15 Feb 2009, Oliver Endriss wrote:
This changeset _must_ be reverted! It breaks all kernels since 2.6.27
for applications which use DVB and require a low interrupt latency.
It is a very bad idea to call the demuxer to process data buffers with
interrupts disabled!
On Mon, 16 Feb 2009, Trent Piepho wrote:
I agree, this is bad. The demuxer is far too much work to be done with
IRQs off. IMHO, even doing it under a spin-lock is excessive. It should
be a mutex. Drivers should use a work-queue to feed the demuxer.
Thank you for testing this changeset and discovering the issues on it.
Cc: Trent Piepho <xyzzy@speakeasy.org>
Cc: Hartmut <e9hack@googlemail.com>
Cc: Oliver Endriss <o.endriss@gmx.de>
Cc: Andreas Oberritter <obi@linuxtv.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
The functions dvb_dmxdev_section_callback, dvb_dmxdev_ts_callback,
dvb_dmx_swfilter_packet, dvb_dmx_swfilter_packets, dvb_dmx_swfilter and
dvb_dmx_swfilter_204 may be called from both interrupt and process
context. Therefore they need to be protected by spin_lock_irqsave()
instead of spin_lock().
This fixes a deadlock discovered by lockdep.
Signed-off-by: Andreas Oberritter <obi@linuxtv.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
__FUNCTION__ is gcc-specific, use __func__
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Acked-by: Oliver Endriss <o.endriss@gmx.de>
Signed-off-by: Michael Krufky <mkrufky@linuxtv.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
Previously, the macro DVR_FEED, which is used to recognize and filter
out duplicate packets going to the DVR device, used the TS_PAYLOAD_ONLY
flag to identify a packet's destination.
This kind of filtering was introduced by the following two changesets:
Now, that it is possible to record TS PIDs using the demux device by
setting the output type to DMX_OUT_TSDEMUX_TAP, checking TS_PAYLOAD_ONLY
is not sufficient anymore. Therefore another flag, TS_DEMUX, is added to
specify the output type of a feed.
This allows multiple clients to filter the same TS PID on a demux device
simultaneously.
Signed-off-by: Andreas Oberritter <obi@linuxtv.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
Fix several instances of dvb-core functions using mutex_lock_interruptible
and returning -ERESTARTSYS where the calling function will either never
retry or never check the return value.
These cause a race condition with dvb_dmxdev_filter_free and
dvb_dvr_release, both of which are filesystem release functions whose
return value is ignored and will never be retried. When this happens it
becomes impossible to open dvr0 again (-EBUSY) since it has not been
released properly.
Signed-off-by: Simon Arlott <simon@fire.lp0.eu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-By: Johannes Stezenbach <js@linuxtv.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
Semaphore to mutex conversion.
The conversion was generated via scripts, and the result was validated
automatically via a script as well.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
Fix a bug in the software demux which causes large MPEG sections to be lost
when they follow very small sections.
The problem happens when two sections begin in the same transport packet. The
dvb_demux code resets its buffer only before the first of these sections.
This means that when the second (or subsequent) section begins, there is up to
182 bytes of buffer space already used. If the following section is close to
the maximum size, it currently won't fit in the (4096-byte) buffer and is
thrown away.
The fix is simply to enlarge the buffer by the size of one transport packet
and correct one usage of the SECFEED_SIZE definition where what is really
meant is the maximum size of a section.
Signed-off-by: Mark Adams <mark147m@gmail.com>
Signed-off-by: Michael Krufky <mkrufky@linuxtv.org>
Cc: Johannes Stezenbach <js@linuxtv.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Use INIT_LIST_HEAD for frontend_list.
Signed-off-by: Andreas Oberritter <obi@linuxtv.org>
Signed-off-by: Johannes Stezenbach <js@linuxtv.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Removed more unused variables and constants.
Signed-off-by: Andreas Oberritter <obi@linuxtv.org>
Signed-off-by: Johannes Stezenbach <js@linuxtv.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Removed some useless functions and variables.
Signed-off-by: Andreas Oberritter <obi@linuxtv.org>
Signed-off-by: Johannes Stezenbach <js@linuxtv.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Don't return immediately from dvb_dmx_swfilter_section_packet() if CC is not
ok. Otherwise a new feed drops all packets until the first packet with CC=0
arrives.
Signed-off-by: Andreas Oberritter <obi@linuxtv.org>
Signed-off-by: Johannes Stezenbach <js@linuxtv.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
