CCID3 performance depends much on the accuracy of RTT samples. If RTT
samples grow too large, performance can be catastrophically poor.
To limit the amount of possible damage in such cases, the patch
* introduces an upper limit which identifies a maximum `sane' RTT value;
* uses a macro to enforce this upper limit.
Using a macro was given preference, since it is necessary to identify the
calling function in the warning message. Since exceeding this threshold
identifies a critical condition, DCCP_CRIT is used and not DCCP_WARN.
Many thanks to Ian McDonald for collaboration on this issue.
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
In both the sender and the receiver it is possible that the stored
RTT value is accessed before an actual RTT estimate has been computed.
This patch
* initialises the sender RTT to 0
- the sender always accesses the RTT in ccid3_hc_tx_packet_sent
- the RTT is further needed for the window counter algorithm
* replaces the receiver initialisation of 5msec with 0
- which has the same effect and removes an `XXX'
- the RTT value is needed in ccid3_hc_rx_packet_recv as rtt_prev
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
The function ccid3_hc_tx_insert_options only does a redundant no-op,
as the operation
DCCP_SKB_CB(skb)->dccpd_ccval = hctx->ccid3hctx_last_win_count;
is already performed _unconditionally_ in ccid3_hc_tx_send_packet.
Since there is further no current need for this function, it is removed
entirely. Since furthermore, there is actually no present need for the
entire interface function ccid_hc_tx_insert_options, it was decided to
remove it also, to clean up the interface.
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
This adds a (debug) warning message which is triggered whenever a packet is
discarded due to send failure.
It also adds a conditional, so that an interruption during dccp_wait_for_ccid
is not treated as a `BUG': the rationale is that interruptions are external,
whereas bug warnings are concerned with the internals.
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
This is an optimisation to reduce CPU load. The received feedback is now
only directed to the active CCID component, without requiring processing
also by the inactive one.
As a consequence, a similar test in ccid3.c is now redundant and is
also removed.
Justification:
Currently DCCP works as a unidirectional service, i.e. a listening server
is not at the same time a connecting client.
As far as I can see, several modifications are necessary until that
becomes possible.
At the present time, received feedback is both fed to the rx/tx CCID
modules. In unidirectional service, only one of these is active at any
one time.
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
In migrating towards using the newer functions scaled_div/scaled_div32
for TFRC computations mapped from floating-point onto integer arithmetic,
this completes the last stage of modifications.
In particular, the overflow case for computing X_calc is circumvented by
* breaking the computation into two stages
* the first stage, res = (s*1E6)/R, cannot overflow due to use of u64
* in the second stage, res = (res*1E6)/f, overflow on u32 is avoided due
to (i) returning UINT_MAX in this case (which is logically appropriate)
and (ii) issuing a warning message into the system log (since very likely
there is a problem somewhere else with the parameters)
Lastly, all such scaling operations are now exported into tfrc.h, since
actually this form of scaled computation is specific to TFRC and not to CCID3.
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
Problem:
Most target types in the CCID3 code are u32, so subtle conversion errors
can occur if signed time calculations yield negative results: the original
values are lost in the conversion to unsigned, calculation errors go undetected.
This patch therefore
* sets all critical time types from unsigned to suseconds_t
* avoids comparison between signed/unsigned via type-casting
* provides ample warning messages in case time calculations are negative
These warning messages can be removed at a later stage when the code
has undergone more testing.
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
This simplifies the calculation of a value p for a given fval when the
first loss interval is computed (RFC 3448, 6.3.1). It makes use of the
two new functions scaled_div/scaled_div32 to provide overflow protection.
Additionally, protection against divide-by-zero is extended - in this
case the function will return the maximally possible value of p=100%.
Background:
The maximum fval, f(100%), is approximately 244, i.e. the scaled value of fval
should never exceed 244E6, which fits easily into u32. The problem is the scaling
by 10^6, since additionally R(TT) is in microseconds.
This is resolved by breaking the division into two stages: the first stage
computes fval=(s*10^6)/R, stores that into u64; the second stage computes
fval = (fval*10^6)/X_recv and complains if overflow is reached for u32.
This case is safe since the TFRC reverse-lookup routine then returns p=100%.
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
This replaces the remaining uses of usecs_div with scaled_div32, which
internally uses 64bit division and produces a warning on overflow.
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
This patch
* resolves a bug where packets smaller than 32/64 bytes resulted in sending rates of 0
* supports all sending rates from 1/64 bytes/second up to 4Gbyte/second
* simplifies the present overflow problems in calculations
Current sending rate X and the cached value X_recv of the receiver-estimated
sending rate are both scaled by 64 (2^6) in order to
* cope with low sending rates (minimally 1 byte/second)
* allow upgrading to use a packets-per-second implementation of CCID 3
* avoid calculation errors due to integer arithmetic cut-off
The patch implements a revised strategy from
http://www.mail-archive.com/dccp@vger.kernel.org/msg01040.html
The only difference with regard to that strategy is that t_ipi is already
used in the calculation of the nofeedback timeout, which saves one division.
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
This fixes
1) a bug in the recomputation of the sending rate by the nofeedback
timer when no feedback at all has so far been sent by the receiver:
min_t was used instead of max_t, which is wrong (cf. RFC 3448, p. 10);
2) an error in the computation of larger initial windows: instead of
min(... max()) (cf. RFC 4342, 5.), the code had used max(... max()).
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
This performs two optimisations for the recomputation of the sending rate.
1) Currently the target sending rate X_calc is recalculated whenever
a) the nofeedback timer expires, or
b) a feedback packet is received.
In the (a) case, recomputing X_calc is redundant, since
* the parameters p and RTT do not change in between the
reception of feedback packets;
* the parameter X_recv is either modified from received
feedback or via the nofeedback timer;
* a test (`p == 0') in the nofeedback timer avoids using
a stale/undefined value of X_calc if p was previously 0.
2) The nofeedback timer now only recomputes a timestamp when p == 0.
This is according to step (4) of [RFC 3448, 4.3] and avoids
unnecessarily determining a timestamp.
A debug statement about not updating X is also removed - it helps very
little in debugging and just clutters the logs.
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
This patch follows a suggestion by Ian McDonald and ensures that in
the current code the value of p can not exceed 100%. Such a value is
illegal and would consequently cause a bug condition in tfrc_calc_x().
The receiver case is also tested, and a warning message is added.
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
As Eddie Kohler points out the RFC is Proposed Standard not experimental.
Also removed documentation about deprecated socket option.
Signed-off-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
It simplifies waiting for the CCID module to signal that a packet
is ready to be sent. Other simplifications flow on from this such as
removing constants.
As a result of this EAGAIN is not returned any more by dccp_wait_for_ccid
(which would otherwise lead to unnecessarily discarding the packet in
dccp_write_xmit).
Signed-off-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
Currently WAN router drivers can be built in-kernel while the
register/unregister_wan_device interfaces are built as modules.
This causes:
drivers/built-in.o: In function `cycx_init':
cycx_main.c:(.init.text+0x5c4b): undefined reference to `register_wan_device'
drivers/built-in.o: In function `cycx_exit':
cycx_main.c:(.exit.text+0x560): undefined reference to `unregister_wan_device'
make: *** [.tmp_vmlinux1] Error 1
The problem is caused by tristate -> bool conversion (y or m => y),
so convert WAN_ROUTER_DRIVERS to a tristate so that the correct
dependency is preserved.
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The SHA384 block size should be 128 bytes, not 96 bytes. This was
spotted by Andrew Donofrio.
Fortunately the block size isn't actually used anywhere so this typo
has had no real impact.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Make powerpc's __ilog2_u64() take a 64-bit argument.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
We should not initialize rootfs before all the core initializers have
run. So do it as a separate stage just before starting the regular
driver initializers.
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
As reported by Andy Whitcroft, at least the SLES9 initrd build process
depends on getting the kernel version from the kernel binary. It does
that by simply trawling the binary and looking for the signature of the
"linux_banner" string (the string "Linux version " to be exact. Which
is really broken in itself, but whatever..)
That got broken when the string was changed to allow /proc/version to
change the UTS release information dynamically, and "get_kernel_version"
thus returned "%s" (see commit a2ee8649ba:
"[PATCH] Fix linux banner utsname information").
This just restores "linux_banner" as a static string, which should fix
the version finding. And /proc/version simply uses a different string.
To avoid wasting even that miniscule amount of memory, the early boot
string should really be marked __initdata, but that just causes the same
bug in SLES9 to re-appear, since it will then find other occurrences of
"Linux version " first.
Cc: Andy Whitcroft <apw@shadowen.org>
Acked-by: Herbert Poetzl <herbert@13thfloor.at>
Cc: Andi Kleen <ak@suse.de>
Cc: Andrew Morton <akpm@osdl.org>
Cc: Steve Fox <drfickle@us.ibm.com>
Acked-by: Olaf Hering <olaf@aepfle.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This looks like a result of too many auto-merges. The
CONFIG_ARCH_VERSATILE case was handled a total of 6 times.
This kills 5 of them.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
--
drivers/net/smc91x.h | 90 ---------------------------------------------------
1 file changed, 90 deletions(-)
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Fix sizing of big_bytes in the case of vlan frames. The 4
VLAN_HLEN bytes were omitted, leading to sizing the big buffer
4 bytes smaller than it should be. Due to how rx buffers are
carved from pages, this was harmless for the common (9000, 1500)
byte MTUs, but could lead to data corruption for some MTUs.
Signed-off-by: Brice Goglin <brice@myri.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Receive full vlan frames into smalls when running with a jumbo MTU.
Signed-off-by: Brice Goglin <brice@myri.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Drop the old routines that used the physically contigous skb now
that we use the physical pages. And rename myri10ge_page_rx_done()
to myri10ge_rx_done() as it was previously.
Signed-off-by: Brice Goglin <brice@myri.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Switch to physical page skb, by calling the new page-based
allocation routines and using myri10ge_page_rx_done().
Signed-off-by: Brice Goglin <brice@myri.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Add physical page skb allocation routines and page based rx_done,
to be used by upcoming patches.
Signed-off-by: Brice Goglin <brice@myri.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Indentation cleanups to synchronize to our tree which is automatically
indent'ed.
Signed-off-by: Brice Goglin <brice@myri.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
This driver tries to enable/disable NAPI at runtime, but
does so in an unsafe manner, and the NAPI interrupt handling is
a mess. Replace it with a compile time selected NAPI implementation.
Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Since macb is a chip-internal device, use __raw_readl and
__raw_writel instead of readl/writel. This will perform native-endian
accesses, which is the right thing to do on both AVR32 and ARM devices.
Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
The macb driver calls schedule_delayed_work() and friends, so we need
to use a struct delayed_work along with it. The conversion was
explained by David Howells on lkml Dec 5 2006:
http://lkml.org/lkml/2006/12/5/269
Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Fix compilation failures when building the ucc_geth driver with spinlock
debugging.
Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
The driver is usable on the newer SAM9 processors so replace all text
references to AT91RM9200 with just AT91.
The controller bug where all the words are byte-swapped is fixed on the
AT91SAM9 processors. The byte-swapping work-around therefore only needs
to be done if cpu_is_at91rm9200().
[Original patch from Wojtek Kaniewski]
The AT91RM9200 and AT91SAM9260 processors support two MMC/SD slots - the
slot which is connected is now passed via the platform_data and the
correct slot selected in the AT91_MCI_SDCR register.
The driver should not be calling at91_set_gpio_output() since the VCC
pin should have already been configured as an output in the
processor/board setup code. The driver should call
at91_set_gpio_value().
Signed-off-by: Andrew Victor <andrew@sanpeople.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Some controllers report an invalid iomem size, but seem to work
correctly anyway. Change our current error to just a warning and
hope it doesn't cause too much problems.
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Currently on SD/MMC card removal the system exhibits the following message (the platform is ARM Versatile):
prev->state: 2 != TASK_RUNNING??
mmcqd/762[CPU#0]: BUG in __schedule at linux-2.6/kernel/sched.c:3826
(akpm: someone tried to fix this, but it's still wrong)
Signed-off-by: Vitaly Wool <vitalywool@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
A number of small cleanups to the AT91RM9200 MMC driver:
- fix warnings generated by pr_debug().
- prepend "AT91 MMC:" to printk() messages.
Signed-off-by: Andrew Victor <andrew@sanpeople.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
This patch simplifies the AT91RM9200 MMC interrupt handler code so that
it doesn't re-read the Interrupt Status and Interrupt Mask registers
multiple times.
Also defined AT91_MCI_ERRORS instead of using the hard-coded 0xffff0000.
Signed-off-by: Andrew Victor <andrew@sanpeople.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Move the global 'mci_clk' variable into the local 'at91mci_host'
structure.
Signed-off-by: Andrew Victor <andrew@sanpeople.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Use the I/O base-address and IRQ passed to the driver via the
platform_device resources instead of using hardcoded values.
Signed-off-by: Andrew Victor <andrew@sanpeople.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
The I/O base address is now stored in the 'at91mci_host' structure. We
therefore have to pass this structure to at91_mci_read() and
at91_mci_write().
Signed-off-by: Andrew Victor <andrew@sanpeople.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
On a CPU with aliases the IDE core needs to flush caches in the special
IDE variants of insw, insl etc. If IDE support is built as a module this
will only work if local_flush_data_cache_page happens is exported as a
module.
As per policy export local_flush_data_cache_page as GPL symbol only.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This eleminates the need to include ptrace.h into system.h and fixes a
harmless namespace conflict on the PC symbol in bpck.c.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
