Skip to content

K
kernel_linux

OpenHarmony / kernel_linux
上一次同步 3 年多

通知 13
Star 8
Fork 2
K
kernel_linux
切换分支/标签
  1. 27 1月, 2011 1 次提交
    • D
      net: Implement read-only protection and COW'ing of metrics. · 62fa8a84
      由 David S. Miller 提交于 
      Routing metrics are now copy-on-write.

Initially a route entry points it's metrics at a read-only location.
If a routing table entry exists, it will point there.  Else it will
point at the all zero metric place-holder called 'dst_default_metrics'.

The writeability state of the metrics is stored in the low bits of the
metrics pointer, we have two bits left to spare if we want to store
more states.

For the initial implementation, COW is implemented simply via kmalloc.
However future enhancements will change this to place the writable
metrics somewhere else, in order to increase sharing.  Very likely
this "somewhere else" will be the inetpeer cache.

Note also that this means that metrics updates may transiently fail
if we cannot COW the metrics successfully.

But even by itself, this patch should decrease memory usage and
increase cache locality especially for routing workloads.  In those
cases the read-only metric copies stay in place and never get written
to.

TCP workloads where metrics get updated, and those rare cases where
PMTU triggers occur, will take a very slight performance hit.  But
that hit will be alleviated when the long-term writable metrics
move to a more sharable location.

Since the metrics storage went from a u32 array of RTAX_MAX entries to
what is essentially a pointer, some retooling of the dst_entry layout
was necessary.

Most importantly, we need to preserve the alignment of the reference
count so that it doesn't share cache lines with the read-mostly state,
as per Eric Dumazet's alignment assertion checks.

The only non-trivial bit here is the move of the 'flags' member into
the writeable cacheline.  This is OK since we are always accessing the
flags around the same moment when we made a modification to the
reference count.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      62fa8a84
  3. 25 1月, 2011 4 次提交
  5. 24 1月, 2011 5 次提交
    • R
      Remove MAYBE_BUILD_BUG_ON · 1765e3a4
      由 Rusty Russell 提交于 
      Now BUILD_BUG_ON() can handle optimizable constants, we don't need
MAYBE_BUILD_BUG_ON any more.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
      1765e3a4
    • R
      BUILD_BUG_ON: make it handle more cases · 7ef88ad5
      由 Rusty Russell 提交于 
      BUILD_BUG_ON used to use the optimizer to do code elimination or fail
at link time; it was changed to first the size of a negative array (a
nicer compile time error), then (in
8c87df45) to a bitfield.

This forced us to change some non-constant cases to MAYBE_BUILD_BUG_ON();
as Jan points out in that commit, it didn't work as intended anyway.

bitfields: needs a literal constant at parse time, and can't be put under
	"if (__builtin_constant_p(x))" for example.
negative array: can handle anything, but if the compiler can't tell it's
	a constant, silently has no effect.
link time: breaks link if the compiler can't determine the value, but the
	linker output is not usually as informative as a compiler error.

If we use the negative-array-size method *and* the link time trick,
we get the ability to use BUILD_BUG_ON() under __builtin_constant_p()
branches, and maximal ability for the compiler to detect errors at
build time.

We also document it thoroughly.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Cc: Jan Beulich <JBeulich@novell.com>
Acked-by: NHollis Blanchard <hollisb@us.ibm.com>
      7ef88ad5
    • L
      param: add null statement to compiled-in module params · b75be420
      由 Linus Walleij 提交于 
      Add an unused struct declaration statement requiring a
terminating semicolon to the compile-in case to provoke an
error if __MODULE_INFO() is used without the terminating
semicolon. Previously MODULE_ALIAS("foo") (no semicolon)
compiled fine if MODULE was not selected.

Cc: Dan Carpenter <error27@gmail.com>
Signed-off-by: NLinus Walleij <linus.walleij@stericsson.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
      b75be420
    • R
      module: fix linker error for MODULE_VERSION when !MODULE and CONFIG_SYSFS=n · 3b90a5b2
      由 Rusty Russell 提交于 
      lib/built-in.o:(__modver+0x8): undefined reference to `__modver_version_show'
lib/built-in.o:(__modver+0x2c): undefined reference to `__modver_version_show'

Simplest to just not emit anything: if they've disabled SYSFS they probably
want the smallest kernel possible.
Reported-by: NRandy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
      3b90a5b2
    • D
      module: show version information for built-in modules in sysfs · e94965ed
      由 Dmitry Torokhov 提交于 
      Currently only drivers that are built as modules have their versions
shown in /sys/module/<module_name>/version, but this information might
also be useful for built-in drivers as well. This especially important
for drivers that do not define any parameters - such drivers, if
built-in, are completely invisible from userspace.

This patch changes MODULE_VERSION() macro so that in case when we are
compiling built-in module, version information is stored in a separate
section. Kernel then uses this data to create 'version' sysfs attribute
in the same fashion it creates attributes for module parameters.
Signed-off-by: NDmitry Torokhov <dtor@vmware.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
      e94965ed
  7. 23 1月, 2011 1 次提交
    • B
      genirq: Add IRQ affinity notifiers · cd7eab44
      由 Ben Hutchings 提交于 
      When initiating I/O on a multiqueue and multi-IRQ device, we may want
to select a queue for which the response will be handled on the same
or a nearby CPU.  This requires a reverse-map of IRQ affinity.  Add a
notification mechanism to support this.

This is based closely on work by Thomas Gleixner <tglx@linutronix.de>.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>
Cc: linux-net-drivers@solarflare.com
Cc: Tom Herbert <therbert@google.com>
Cc: David Miller <davem@davemloft.net>
LKML-Reference: <1295470904.11126.84.camel@bwh-desktop>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
      cd7eab44
  9. 22 1月, 2011 3 次提交
  11. 21 1月, 2011 10 次提交
  13. 20 1月, 2011 9 次提交
    • J
      netfilter: xtables: remove duplicate member · ba12b130
      由 Jan Engelhardt 提交于 
      Accidentally missed removing the old out-of-union "inverse" member,
which caused the struct size to change which then gives size mismatch
warnings when using an old iptables.

It is interesting to see that gcc did not warn about this before.
(Filed http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47376 )
Signed-off-by: NJan Engelhardt <jengelh@medozas.de>
      ba12b130
    • T
      lockdep: Move early boot local IRQ enable/disable status to init/main.c · 2ce802f6
      由 Tejun Heo 提交于 
      During early boot, local IRQ is disabled until IRQ subsystem is
properly initialized.  During this time, no one should enable
local IRQ and some operations which usually are not allowed with
IRQ disabled, e.g. operations which might sleep or require
communications with other processors, are allowed.

lockdep tracked this with early_boot_irqs_off/on() callbacks.
As other subsystems need this information too, move it to
init/main.c and make it generally available.  While at it,
toggle the boolean to early_boot_irqs_disabled instead of
enabled so that it can be initialized with %false and %true
indicates the exceptional condition.
Signed-off-by: NTejun Heo <tj@kernel.org>
Acked-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: NPekka Enberg <penberg@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
LKML-Reference: <20110120110635.GB6036@htj.dyndns.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
      2ce802f6
    • J
      netfilter: xtables: remove extraneous header that slipped in · 5d844928
      由 Jan Engelhardt 提交于 
      Commit 0b8ad876 (netfilter: xtables: add missing header files to export
list) erroneously added this.
Signed-off-by: NJan Engelhardt <jengelh@medozas.de>
Signed-off-by: NPatrick McHardy <kaber@trash.net>
      5d844928
    • J
      net_sched: implement a root container qdisc sch_mqprio · b8970f0b
      由 John Fastabend 提交于 
      This implements a mqprio queueing discipline that by default creates
a pfifo_fast qdisc per tx queue and provides the needed configuration
interface.

Using the mqprio qdisc the number of tcs currently in use along
with the range of queues alloted to each class can be configured. By
default skbs are mapped to traffic classes using the skb priority.
This mapping is configurable.

Configurable parameters,

struct tc_mqprio_qopt {
	__u8    num_tc;
	__u8    prio_tc_map[TC_BITMASK + 1];
	__u8    hw;
	__u16   count[TC_MAX_QUEUE];
	__u16   offset[TC_MAX_QUEUE];
};

Here the count/offset pairing give the queue alignment and the
prio_tc_map gives the mapping from skb->priority to tc.

The hw bit determines if the hardware should configure the count
and offset values. If the hardware bit is set then the operation
will fail if the hardware does not implement the ndo_setup_tc
operation. This is to avoid undetermined states where the hardware
may or may not control the queue mapping. Also minimal bounds
checking is done on the count/offset to verify a queue does not
exceed num_tx_queues and that queue ranges do not overlap. Otherwise
it is left to user policy or hardware configuration to create
useful mappings.

It is expected that hardware QOS schemes can be implemented by
creating appropriate mappings of queues in ndo_tc_setup().

One expected use case is drivers will use the ndo_setup_tc to map
queue ranges onto 802.1Q traffic classes. This provides a generic
mechanism to map network traffic onto these traffic classes and
removes the need for lower layer drivers to know specifics about
traffic types.
Signed-off-by: NJohn Fastabend <john.r.fastabend@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      b8970f0b
    • J
      net: implement mechanism for HW based QOS · 4f57c087
      由 John Fastabend 提交于 
      This patch provides a mechanism for lower layer devices to
steer traffic using skb->priority to tx queues. This allows
for hardware based QOS schemes to use the default qdisc without
incurring the penalties related to global state and the qdisc
lock. While reliably receiving skbs on the correct tx ring
to avoid head of line blocking resulting from shuffling in
the LLD. Finally, all the goodness from txq caching and xps/rps
can still be leveraged.

Many drivers and hardware exist with the ability to implement
QOS schemes in the hardware but currently these drivers tend
to rely on firmware to reroute specific traffic, a driver
specific select_queue or the queue_mapping action in the
qdisc.

By using select_queue for this drivers need to be updated for
each and every traffic type and we lose the goodness of much
of the upstream work. Firmware solutions are inherently
inflexible. And finally if admins are expected to build a
qdisc and filter rules to steer traffic this requires knowledge
of how the hardware is currently configured. The number of tx
queues and the queue offsets may change depending on resources.
Also this approach incurs all the overhead of a qdisc with filters.

With the mechanism in this patch users can set skb priority using
expected methods ie setsockopt() or the stack can set the priority
directly. Then the skb will be steered to the correct tx queues
aligned with hardware QOS traffic classes. In the normal case with
single traffic class and all queues in this class everything
works as is until the LLD enables multiple tcs.

To steer the skb we mask out the lower 4 bits of the priority
and allow the hardware to configure upto 15 distinct classes
of traffic. This is expected to be sufficient for most applications
at any rate it is more then the 8021Q spec designates and is
equal to the number of prio bands currently implemented in
the default qdisc.

This in conjunction with a userspace application such as
lldpad can be used to implement 8021Q transmission selection
algorithms one of these algorithms being the extended transmission
selection algorithm currently being used for DCB.
Signed-off-by: NJohn Fastabend <john.r.fastabend@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      4f57c087
    • V
      net_device: add support for network device groups · cbda10fa
      由 Vlad Dogaru 提交于 
      Net devices can now be grouped, enabling simpler manipulation from
userspace. This patch adds a group field to the net_device structure, as
well as rtnetlink support to query and modify it.
Signed-off-by: NVlad Dogaru <ddvlad@rosedu.org>
Acked-by: NJamal Hadi Salim <hadi@cyberus.ca>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      cbda10fa
    • S
      sctp: user perfect name for Delayed SACK Timer option · 4580ccc0
      由 Shan Wei 提交于 
      The option name of Delayed SACK Timer should be SCTP_DELAYED_SACK,
not SCTP_DELAYED_ACK.

Left SCTP_DELAYED_ACK be concomitant with SCTP_DELAYED_SACK,
for making compatibility with existing applications.

Reference:
8.1.19.  Get or Set Delayed SACK Timer (SCTP_DELAYED_SACK)
（http://tools.ietf.org/html/draft-ietf-tsvwg-sctpsocket-25)
Signed-off-by: NShan Wei <shanwei@cn.fujitsu.com>
Acked-by: NWei Yongjun <yjwei@cn.fujitsu.com>
Acked-by: NVlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      4580ccc0
    • J
      netfilter: xtables: connlimit revision 1 · cc4fc022
      由 Jan Engelhardt 提交于 
      This adds destination address-based selection. The old "inverse"
member is overloaded (memory-wise) with a new "flags" variable,
similar to how J.Park did it with xt_string rev 1. Since revision 0
userspace only sets flag 0x1, no great changes are made to explicitly
test for different revisions.
Signed-off-by: NJan Engelhardt <jengelh@medozas.de>
      cc4fc022
    • J
      Bluetooth: Fix race condition with conn->sec_level · 765c2a96
      由 Johan Hedberg 提交于 
      The conn->sec_level value is supposed to represent the current level of
security that the connection has. However, by assigning to it before
requesting authentication it will have the wrong value during the
authentication procedure. To fix this a pending_sec_level variable is
added which is used to track the desired security level while making
sure that sec_level always represents the current level of security.
Signed-off-by: NJohan Hedberg <johan.hedberg@nokia.com>
Signed-off-by: NGustavo F. Padovan <padovan@profusion.mobi>
      765c2a96
  15. 19 1月, 2011 7 次提交