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  1. 14 5月, 2014 7 次提交
  3. 13 5月, 2014 2 次提交
  5. 12 5月, 2014 1 次提交
  7. 09 5月, 2014 2 次提交
  9. 08 5月, 2014 4 次提交
  11. 06 5月, 2014 5 次提交
  13. 05 5月, 2014 3 次提交
  15. 04 5月, 2014 3 次提交
  17. 03 5月, 2014 2 次提交
    • E
      tcp: fix cwnd limited checking to improve congestion control · e114a710
      由 Eric Dumazet 提交于 
      Yuchung discovered tcp_is_cwnd_limited() was returning false in
slow start phase even if the application filled the socket write queue.

All congestion modules take into account tcp_is_cwnd_limited()
before increasing cwnd, so this behavior limits slow start from
probing the bandwidth at full speed.

The problem is that even if write queue is full (aka we are _not_
application limited), cwnd can be under utilized if TSO should auto
defer or TCP Small queues decided to hold packets.

So the in_flight can be kept to smaller value, and we can get to the
point tcp_is_cwnd_limited() returns false.

With TCP Small Queues and FQ/pacing, this issue is more visible.

We fix this by having tcp_cwnd_validate(), which is supposed to track
such things, take into account unsent_segs, the number of segs that we
are not sending at the moment due to TSO or TSQ, but intend to send
real soon. Then when we are cwnd-limited, remember this fact while we
are processing the window of ACKs that comes back.

For example, suppose we have a brand new connection with cwnd=10; we
are in slow start, and we send a flight of 9 packets. By the time we
have received ACKs for all 9 packets we want our cwnd to be 18.
We implement this by setting tp->lsnd_pending to 9, and
considering ourselves to be cwnd-limited while cwnd is less than
twice tp->lsnd_pending (2*9 -> 18).

This makes tcp_is_cwnd_limited() more understandable, by removing
the GSO/TSO kludge, that tried to work around the issue.

Note the in_flight parameter can be removed in a followup cleanup
patch.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NNeal Cardwell <ncardwell@google.com>
Signed-off-by: NYuchung Cheng <ycheng@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      e114a710
    • G
      mdio_bus: implement devm_mdiobus_alloc/devm_mdiobus_free · 6d48f44b
      由 Grygorii Strashko 提交于 
      Add a resource managed devm_mdiobus_alloc[_size]()/devm_mdiobus_free()
to automatically clean up MDIO bus alocations made by MDIO drivers,
thus leading to simplified MDIO drivers code.

Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Acked-and-tested-by: NLad, Prabhakar <prabhakar.csengg@gmail.com>
Signed-off-by: NGrygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      6d48f44b
  19. 01 5月, 2014 3 次提交
  21. 29 4月, 2014 1 次提交
  23. 28 4月, 2014 6 次提交
    • S
      ftrace/module: Hardcode ftrace_module_init() call into load_module() · a949ae56
      由 Steven Rostedt (Red Hat) 提交于 
      A race exists between module loading and enabling of function tracer.

	CPU 1				CPU 2
	-----				-----
  load_module()
   module->state = MODULE_STATE_COMING

				register_ftrace_function()
				 mutex_lock(&ftrace_lock);
				 ftrace_startup()
				  update_ftrace_function();
				   ftrace_arch_code_modify_prepare()
				    set_all_module_text_rw();
				   <enables-ftrace>
				    ftrace_arch_code_modify_post_process()
				     set_all_module_text_ro();

				[ here all module text is set to RO,
				  including the module that is
				  loading!! ]

   blocking_notifier_call_chain(MODULE_STATE_COMING);
    ftrace_init_module()

     [ tries to modify code, but it's RO, and fails!
       ftrace_bug() is called]

When this race happens, ftrace_bug() will produces a nasty warning and
all of the function tracing features will be disabled until reboot.

The simple solution is to treate module load the same way the core
kernel is treated at boot. To hardcode the ftrace function modification
of converting calls to mcount into nops. This is done in init/main.c
there's no reason it could not be done in load_module(). This gives
a better control of the changes and doesn't tie the state of the
module to its notifiers as much. Ftrace is special, it needs to be
treated as such.

The reason this would work, is that the ftrace_module_init() would be
called while the module is in MODULE_STATE_UNFORMED, which is ignored
by the set_all_module_text_ro() call.

Link: http://lkml.kernel.org/r/1395637826-3312-1-git-send-email-indou.takao@jp.fujitsu.comReported-by: NTakao Indoh <indou.takao@jp.fujitsu.com>
Acked-by: NRusty Russell <rusty@rustcorp.com.au>
Cc: stable@vger.kernel.org # 2.6.38+
Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>
      a949ae56
    • T
      genirq: x86: Ensure that dynamic irq allocation does not conflict · 62a08ae2
      由 Thomas Gleixner 提交于 
      On x86 the allocation of irq descriptors may allocate interrupts which
are in the range of the GSI interrupts. That's wrong as those
interrupts are hardwired and we don't have the irq domain translation
like PPC. So one of these interrupts can be hooked up later to one of
the devices which are hard wired to it and the io_apic init code for
that particular interrupt line happily reuses that descriptor with a
completely different configuration so hell breaks lose.

Inside x86 we allocate dynamic interrupts from above nr_gsi_irqs,
except for a few usage sites which have not yet blown up in our face
for whatever reason. But for drivers which need an irq range, like the
GPIO drivers, we have no limit in place and we don't want to expose
such a detail to a driver.

To cure this introduce a function which an architecture can implement
to impose a lower bound on the dynamic interrupt allocations.

Implement it for x86 and set the lower bound to nr_gsi_irqs, which is
the end of the hardwired interrupt space, so all dynamic allocations
happen above.

That not only allows the GPIO driver to work sanely, it also protects
the bogus callsites of create_irq_nr() in hpet, uv, irq_remapping and
htirq code. They need to be cleaned up as well, but that's a separate
issue.
Reported-by: NJin Yao <yao.jin@linux.intel.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Tested-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Cc: Mathias Nyman <mathias.nyman@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: H. Peter Anvin <hpa@linux.intel.com>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Krogerus Heikki <heikki.krogerus@intel.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Link: http://lkml.kernel.org/r/alpine.DEB.2.02.1404241617360.28206@ionos.tec.linutronix.deSigned-off-by: NThomas Gleixner <tglx@linutronix.de>
      62a08ae2
    • R
      linux/interrupt.h: fix new kernel-doc warnings · def5f127
      由 Randy Dunlap 提交于 
      Fix new kernel-doc warnings in <linux/interrupt.h>:

Warning(include/linux/interrupt.h:219): No description found for parameter 'cpumask'
Warning(include/linux/interrupt.h:219): Excess function parameter 'mask' description in 'irq_set_affinity'
Warning(include/linux/interrupt.h:236): No description found for parameter 'cpumask'
Warning(include/linux/interrupt.h:236): Excess function parameter 'mask' description in 'irq_force_affinity'
Signed-off-by: NRandy Dunlap <rdunlap@infradead.org>
Link: http://lkml.kernel.org/r/535DD2FD.7030804@infradead.orgSigned-off-by: NThomas Gleixner <tglx@linutronix.de>
      def5f127
    • C
      sched, cls: check if we could overwrite actions when changing a filter · 2f7ef2f8
      由 Cong Wang 提交于 
      When actions are attached to a filter, they are a part of the filter
itself, so when changing a filter we should allow to overwrite the actions
inside as well.

In my specific case, when I tried to _append_ a new action to an existing
filter which already has an action, I got EEXIST since kernel refused
to overwrite the existing one in kernel.

This patch checks if we are changing the filter checking NLM_F_CREATE flag
(Sigh, filters don't use NLM_F_REPLACE...) and then passes the boolean down
to actions. This fixes the problem above.

Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NCong Wang <cwang@twopensource.com>
Signed-off-by: NJamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      2f7ef2f8
    • M
      FDDI: Reformat <linux/if_fddi.h> for 8-character tabs · eb11022d
      由 Maciej W. Rozycki 提交于 
      Some of our FDDI support code has been apparently written with an
assumption that tabs are 4-character wide.  In preparation to the next
change this update reformats <linux/if_fddi.h> so that it stays within 79
columns and otherwise renders correctly with 8-character tabs.  No
functional change.
Signed-off-by: NMaciej W. Rozycki <macro@linux-mips.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      eb11022d
    • W
      word-at-a-time: avoid undefined behaviour in zero_bytemask macro · ec6931b2
      由 Will Deacon 提交于 
      The asm-generic, big-endian version of zero_bytemask creates a mask of
bytes preceding the first zero-byte by left shifting ~0ul based on the
position of the first zero byte.

Unfortunately, if the first (top) byte is zero, the output of
prep_zero_mask has only the top bit set, resulting in undefined C
behaviour as we shift left by an amount equal to the width of the type.
As it happens, GCC doesn't manage to spot this through the call to fls(),
but the issue remains if architectures choose to implement their shift
instructions differently.

An example would be arch/arm/ (AArch32), where LSL Rd, Rn, #32 results
in Rd == 0x0, whilst on arch/arm64 (AArch64) LSL Xd, Xn, #64 results in
Xd == Xn.

Rather than check explicitly for the problematic shift, this patch adds
an extra shift by 1, replacing fls with __fls. Since zero_bytemask is
never called with a zero argument (has_zero() is used to check the data
first), we don't need to worry about calling __fls(0), which is
undefined.

Cc: <stable@vger.kernel.org>
Cc: Victor Kamensky <victor.kamensky@linaro.org>
Signed-off-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      ec6931b2
  25. 27 4月, 2014 1 次提交