linux-toradex.git/drivers/xen/tmem.c, branch v3.15

Merge tag 'stable/for-linus-3.11-rc0-tag-two' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen

2013-07-03T20:12:42+00:00

Pull Xen bugfixes from Konrad Rzeszutek Wilk:
 - Fix memory leak when CPU hotplugging.
 - Compile bugs with various #ifdefs
 - Fix state changes in Xen PCI front not dealing well with new
   toolstack.
 - Cleanups in code (use pr_*, fix 80 characters splits, etc)
 - Long standing bug in double-reporting the steal time

* tag 'stable/for-linus-3.11-rc0-tag-two' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
  xen/time: remove blocked time accounting from xen "clockchip"
  xen: Convert printks to pr_
  xen: ifdef CONFIG_HIBERNATE_CALLBACKS xen_*_suspend
  xen/pcifront: Deal with toolstack missing 'XenbusStateClosing' state.
  xen/time: Free onlined per-cpu data structure if we want to online it again.
  xen/time: Check that the per_cpu data structure has data before freeing.
  xen/time: Don't leak interrupt name when offlining.
  xen/time: Encapsulate the struct clock_event_device in another structure.
  xen/spinlock: Don't leak interrupt name when offlining.
  xen/smp: Don't leak interrupt name when offlining.
  xen/smp: Set the per-cpu IRQ number to a valid default.
  xen/smp: Introduce a common structure to contain the IRQ name and interrupt line.
  xen/smp: Coalesce the free_irq calls in one function.
  xen-pciback: fix error return code in pcistub_irq_handler_switch()

xen: Convert printks to pr_

2013-06-28T15:19:58+00:00

Convert printks to pr_ (excludes printk(KERN_DEBUG...)
to be more consistent throughout the xen subsystem.

Add pr_fmt with KBUILD_MODNAME or "xen:" KBUILD_MODNAME
Coalesce formats and add missing word spaces
Add missing newlines
Align arguments and reflow to 80 columns
Remove DRV_NAME from formats as pr_fmt adds the same content

This does change some of the prefixes of these messages
but it also does make them more consistent.

Signed-off-by: Joe Perches 
Signed-off-by: Konrad Rzeszutek Wilk

xen/tmem: Don't over-write tmem_frontswap_poolid after tmem_frontswap_init set it.

2013-06-10T14:14:33+00:00

Commit 10a7a0771399a57a297fca9615450dbb3f88081a ("xen: tmem: enable Xen
tmem shim to be built/loaded as a module") allows the tmem module
to be loaded any time. For this work the frontswap API had to
be able to asynchronously to call tmem_frontswap_init before
or after the swap image had been set. That was added in git
commit 905cd0e1bf9ffe82d6906a01fd974ea0f70be97a
("mm: frontswap: lazy initialization to allow tmem backends to build/run as modules").

Which means we could do this (The common case):

 modprobe tmem		[so calls frontswap_register_ops, no ->init]
			 modifies tmem_frontswap_poolid = -1
 swapon /dev/xvda1	[__frontswap_init, calls -> init, tmem_frontswap_poolid is
			 < 0 so tmem hypercall done]

Or the failing one:

 swapon /dev/xvda1	[calls __frontswap_init, sets the need_init bitmap]
 modprobe tmem		[calls frontswap_register_ops, -->init calls, finds out
			tmem_frontswap_poolid is 0, does not make a hypercall.
			Later in the module_init, sets tmem_frontswap_poolid=-1]

Which meant that in the failing case we would not call the hypercall
to initialize the pool and never be able to make any frontswap
backend calls.

Moving the frontswap_register_ops after setting the tmem_frontswap_poolid
fixes it.

Signed-off-by: Konrad Rzeszutek Wilk 
Reviewed-by: Bob Liu

xmem/tmem: fix 'undefined variable' build error.

2013-05-28T13:54:48+00:00

In the (not so useful) kernel configuration where CONFIG_SWAP
is undefined and CONFIG_XEN_SELFBALLOONING is defined,
xen_tmem_init would use undefined variable 'static bool frontswap'.

Added #else to have #define frontswap (0) in the case where
CONFIG_FRONTSWAP is not defined.

Signed-off-by: Frederico Cadete 
Signed-off-by: Konrad Rzeszutek Wilk

xen/tmem: Don't use self[ballooning|shrinking] if frontswap is off.

2013-05-15T14:27:50+00:00

There is no point. We would just squeeze the guest to put more and
more pages in the swap disk without any purpose.

The only time it makes sense to use the selfballooning and shrinking
is when frontswap is being utilized.

Signed-off-by: Konrad Rzeszutek Wilk

xen/tmem: Remove the boot options and fold them in the tmem.X parameters.

2013-05-15T14:27:47+00:00

If tmem is built-in or a module, the user has the option on
the command line to influence it by doing: tmem.
instead of having a variety of "nocleancache", and
"nofrontswap". The others: "noselfballooning" and "selfballooning";
and "noselfshrink" are in a different driver xen-selfballoon.c
and the patches:

 xen/tmem: Remove the usage of 'noselfshrink' and use 'tmem.selfshrink' bool instead.
 xen/tmem: Remove the usage of 'noselfballoon','selfballoon' and use 'tmem.selfballon' bool instead.

remove them.

Also add documentation.

Signed-off-by: Konrad Rzeszutek Wilk

xen/tmem: s/disable_// and change the logic.

2013-05-15T14:27:46+00:00

The variety of disable_[cleancache|frontswap|selfshrinking] are
making this a bit complex. Just remove the "disable_" part and
change the logic around for the "nofrontswap" and "nocleancache"
parameters.

Signed-off-by: Konrad Rzeszutek Wilk

xen/tmem: Fix compile warning.

2013-05-15T14:27:45+00:00

We keep on getting:
drivers/xen/tmem.c:65:13: warning: ‘disable_frontswap_selfshrinking’ defined but not used [-Wunused-variable]

if CONFIG_FRONTSWAP=y and # CONFIG_CLEANCACHE is not set

Found by 0 day test project

Reported-by: Fengguang Wu 
Signed-off-by: Konrad Rzeszutek Wilk

xen/tmem: Split out the different module/boot options.

2013-05-15T14:27:44+00:00

There are three options - depending on what combination of
CONFIG_FRONTSWAP, CONFIG_CLEANCACHE and CONFIG_XEN_SELFBALLOONING
is used. Lets split them out nicely out in three groups to
make it easier to clean up.

Signed-off-by: Konrad Rzeszutek Wilk

xen/tmem: Move all of the boot and module parameters to the top of the file.

2013-05-15T14:27:43+00:00

Just code movement to see the different boot or module parameters.

Signed-off-by: Konrad Rzeszutek Wilk