* Rename blkcg->pd[] to blkcg->cpd[] so that cpd is consistently used
  for blkcg_policy_data.

* Make blkcg_policy->cpd_init_fn() take blkcg_policy_data instead of
  blkcg.  This makes it consistent with blkg_policy_data methods and
  to-be-added cpd alloc/free methods.

* blkcg_policy_data->blkcg and cpd_to_blkcg() added so that
  cpd_init_fn() can determine the associated blkcg from
  blkcg_policy_data.

v2: blkcg_policy_data->blkcg initializations were missing.  Added.
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Arianna Avanzini <avanzini.arianna@gmail.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

The newly added ->pd_alloc_fn() and ->pd_free_fn() deal with pd
(blkg_policy_data) while the older ones use blkg (blkcg_gq).  As using
blkg doesn't make sense for ->pd_alloc_fn() and after allocation pd
can always be mapped to blkg and given that these are policy-specific
methods, it makes sense to converge on pd.

This patch makes all methods deal with pd instead of blkg.  Most
conversions are trivial.  In blk-cgroup.c, a couple method invocation
sites now test whether pd exists instead of policy state for
consistency.  This shouldn't cause any behavioral differences.
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

With the recent addition of alloc and free methods, things became
messier.  This patch reorganizes them according to the followings.

* ->pd_alloc_fn()

  Responsible for allocation and static initializations - the ones
  which can be done independent of where the pd might be attached.

* ->pd_init_fn()

  Initializations which require the knowledge of where the pd is
  attached.

* ->pd_free_fn()

  The counter part of pd_alloc_fn().  Static de-init and freeing.

This leaves ->pd_exit_fn() without any users.  Removed.

While at it, collapse an one liner function throtl_pd_exit(), which
has only one user, into its user.
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

A blkg (blkcg_gq) represents the relationship between a cgroup and
request_queue.  Each active policy has a pd (blkg_policy_data) on each
blkg.  The pd's were allocated by blkcg core and each policy could
request to allocate extra space at the end by setting
blkcg_policy->pd_size larger than the size of pd.

This is a bit unusual but was done this way mostly to simplify error
handling and all the existing use cases could be handled this way;
however, this is becoming too restrictive now that percpu memory can
be allocated without blocking.

This introduces two new mandatory blkcg_policy methods - pd_alloc_fn()
and pd_free_fn() - which are used to allocate and release pd for a
given policy.  As pd allocation is now done from policy side, it can
simply allocate a larger area which embeds pd at the beginning.  This
change makes ->pd_size pointless.  Removed.
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

When a policy gets activated, it needs to allocate and install its
policy data on all existing blkg's (blkcg_gq's).  Because blkg
iteration is protected by a spinlock, it currently counts the total
number of blkg's in the system, allocates the matching number of
policy data on a list and installs them during a single iteration.

This can be simplified by using speculative GFP_NOWAIT allocations
while iterating and falling back to a preallocated policy data on
failure.  If the preallocated one has already been consumed, it
releases the lock, preallocate with GFP_KERNEL and then restarts the
iteration.  This can be a bit more expensive than before but policy
activation is a very cold path and shouldn't matter.
Signed-off-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NJens Axboe <axboe@fb.com>

Since ec13b1d6 ("blkcg: always create the blkcg_gq for the root
blkcg"), a request_list always has its blkg associated.  Drop
unnecessary rl->blkg NULL test from blk_put_rl().
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

Add a function to determine the path length of a kernfs node.  This
for now will be used by writeback tracepoint updates.
Signed-off-by: NTejun Heo <tj@kernel.org>
Acked-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NJens Axboe <axboe@fb.com>

wb's (bdi_writeback's) are currently keyed by memcg ID; however, in an
earlier implementation, wb's were keyed by blkcg ID.
bdi_for_each_wb() walks bdi->cgwb_tree in the ascending ID order and
allows iterations to start from an arbitrary ID which is used to
interrupt and resume iterations.

Unfortunately, while changing wb to be keyed by memcg ID instead of
blkcg, bdi_for_each_wb() was missed and is still assuming that wb's
are keyed by blkcg ID.  This doesn't affect iterations which don't get
interrupted but bdi_split_work_to_wbs() makes use of iteration
resuming on allocation failures and thus may incorrectly skip or
repeat wb's.

Fix it by changing bdi_for_each_wb() to take memcg IDs instead of
blkcg IDs and updating bdi_split_work_to_wbs() accordingly.
Signed-off-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NJens Axboe <axboe@fb.com>

This allows cgroup subsystems to use a different name on the unified
hierarchy.  cgroup_subsys->name is used on the unified hierarchy,
->legacy_name elsewhere.  If ->legacy_name is not explicitly set, it's
automatically set to ->name and the userland visible behavior remains
unchanged.

v2: Make parse_cgroupfs_options() only consider ->legacy_name as mount
    options are used only on legacy hierarchies.  Suggested by Li
    Zefan.
Signed-off-by: NTejun Heo <tj@kernel.org>
Acked-by: NLi Zefan <lizefan@huawei.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: cgroups@vger.kernel.org

It's pretty unusual to have an int as a private data field and it
makes it impossible to carray a pointer value through it.  Let's make
it an unsigned long.  AFAICS, this shouldn't break anything.
Signed-off-by: NTejun Heo <tj@kernel.org>
Acked-by: NLi Zefan <lizefan@huawei.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>

Traditionally, each cgroup controller implemented whatever interface
it wanted leading to interfaces which are widely inconsistent.
Examining the requirements of the controllers readily yield that there
are only a few control schemes shared among all.

Two major controllers already had to implement new interface for the
unified hierarchy due to significant structural changes.  Let's take
the chance to establish common conventions throughout all controllers.

This patch defines CGROUP_WEIGHT_MIN/DFL/MAX to be used on all weight
based control knobs and documents the conventions that controllers
should follow on the unified hierarchy.  Except for io.weight knob,
all existing unified hierarchy knobs are already compliant.  A
follow-up patch will update io.weight.

v2: Added descriptions of min, low and high knobs.
Signed-off-by: NTejun Heo <tj@kernel.org>
Acked-by: NJohannes Weiner <hannes@cmpxchg.org>
Cc: Li Zefan <lizefan@huawei.com>
Cc: Peter Zijlstra <peterz@infradead.org>

Commit 4104d326 ("ftrace: Remove global function list and call function
directly") simplified the ftrace code by removing the global_ops list with a
new design. But this cleanup also broke the filtering of PIDs that are added
to the set_ftrace_pid file.

Add back the proper hooks to have pid filtering working once again.

Cc: stable@vger.kernel.org # 3.16+
Reported-by: NMatt Fleming <matt@console-pimps.org>
Reported-by: NRichard Weinberger <richard.weinberger@gmail.com>
Tested-by: NMatt Fleming <matt@console-pimps.org>
Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>

After commit 8d86e4fc ("mmc: sdhci-esdhc-imx: Call mmc_of_parse()"),
it's not used anymore.
Signed-off-by: NDong Aisheng <aisheng.dong@freescale.com>
Reviewed-by: NJohan Derycke <johan.derycke@barco.com>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

By default all the sensors are runtime suspended state (lowest power
state). During Linux suspend process, all the run time suspended
devices are resumed and then suspended. This caused all sensors to
power up and introduced delay in suspend time, when we introduced
runtime PM for HID sensors. The opposite process happens during resume
process.

To fix this, we do powerup process of the sensors only when the request
is issued from user (raw or tiggerred). In this way when runtime,
resume calls for powerup it will simply return as this will not match
user requested state.

Note this is a regression fix as the increase in suspend / resume
times can be substantial (report of 8 seconds on Len's laptop!)
Signed-off-by: NSrinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Tested-by: NLen Brown <len.brown@intel.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

Don't burden architectures without dynamic task_struct sizing
with the overhead of dynamic sizing.

Also optimize the x86 code a bit by caching task_struct_size.
Acked-and-Tested-by: NDave Hansen <dave.hansen@linux.intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave@sr71.net>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1437128892-9831-3-git-send-email-mingo@kernel.orgSigned-off-by: NIngo Molnar <mingo@kernel.org>

The FPU rewrite removed the dynamic allocations of 'struct fpu'.
But, this potentially wastes massive amounts of memory (2k per
task on systems that do not have AVX-512 for instance).

Instead of having a separate slab, this patch just appends the
space that we need to the 'task_struct' which we dynamically
allocate already.  This saves from doing an extra slab
allocation at fork().

The only real downside here is that we have to stick everything
and the end of the task_struct.  But, I think the
BUILD_BUG_ON()s I stuck in there should keep that from being too
fragile.
Signed-off-by: NDave Hansen <dave.hansen@linux.intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave@sr71.net>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1437128892-9831-2-git-send-email-mingo@kernel.orgSigned-off-by: NIngo Molnar <mingo@kernel.org>

Currently, we set wrong gfp_mask to page_owner info in case of isolated
freepage by compaction and split page.  It causes incorrect mixed
pageblock report that we can get from '/proc/pagetypeinfo'.  This metric
is really useful to measure fragmentation effect so should be accurate.
This patch fixes it by setting correct information.

Without this patch, after kernel build workload is finished, number of
mixed pageblock is 112 among roughly 210 movable pageblocks.

But, with this fix, output shows that mixed pageblock is just 57.
Signed-off-by: NJoonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Switch to my kernel.org alias instead of a badly named gmail address,
which I rarely use.
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Using __printf attributes helps to detect several format string issues
at compile time (even though -Wformat-security is currently disabled in
Makefile).  For example it can detect when formatting a pointer as a
number, like the issue fixed in commit a3fa71c4 ("wl18xx: show
rx_frames_per_rates as an array as it really is"), or when the arguments
do not match the format string, c.f.  for example commit 5ce1aca8
("reiserfs: fix __RASSERT format string").

To prevent similar bugs in the future, add a __printf attribute to every
function prototype which needs one in include/linux/ and lib/.  These
functions were mostly found by using gcc's -Wsuggest-attribute=format
flag.
Signed-off-by: NNicolas Iooss <nicolas.iooss_linux@m4x.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Felipe Balbi <balbi@ti.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

s390 has a constant hugepage size, by setting HPAGE_SHIFT we also change
e.g. the pageblock_order, which should be independent in respect to
hugepage support.

With this patch every architecture is free to define how to check
for hugepage support.
Signed-off-by: NDominik Dingel <dingel@linux.vnet.ibm.com>
Acked-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Cc: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Since no longer limiting max_sectors to BLK_DEF_MAX_SECTORS (commit 34b48db6),
data corruption may occur on ST380013AS drive configured on 82801JI (ICH10 Family)
SATA controller. This patch will allow the driver to limit max_sectors as before

 # cat /sys/block/sdb/queue/max_sectors_kb
 512

I was able to double the max_sectors_kb value up to 16384 on linux-4.2.0-rc2
before seeing corruption, but seems safer to use previous limit. Without this
patch max_sectors_kb will be 32767.

tj: Minor comment update.
Reported-by: NJeff Moyer <jmoyer@redhat.com>
Signed-off-by: NDavid Milburn <dmilburn@redhat.com>
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: stable@vger.kernel.org # v3.19 and later
Fixes: 34b48db6 ("block: remove artifical max_hw_sectors cap")

Some devices lose data on TRIM whether queued or not.  This patch adds
a horkage to disable TRIM.

tj: Collapsed unnecessary if() nesting.
Signed-off-by: NArne Fitzenreiter <arne_f@ipfire.org>
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: stable@vger.kernel.org

The memory error record structure includes as its first field a
bitmask of which subsequent fields are valid. The allows new fields
to be added to the structure while keeping compatibility with older
software that parses these records. This mechanism was used between
versions 2.2 and 2.3 to add four new fields, growing the size of the
structure from 73 bytes to 80. But Linux just added all the new
fields so this test:
	if (gdata->error_data_length >= sizeof(*mem_err))
		cper_print_mem(newpfx, mem_err);
	else
		goto err_section_too_small;
now make Linux complain about old format records being too short.

Add a definition for the old format of the structure and use that
for the minimum size check. Pass the actual size to cper_print_mem()
so it can sanity check the validation_bits field to ensure that if
a BIOS using the old format sets bits as if it were new, we won't
access fields beyond the end of the structure.
Signed-off-by: NTony Luck <tony.luck@intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NMatt Fleming <matt.fleming@intel.com>

They just call file_inode and then the corresponding *_inode_file_wait
function. Just make them static inlines instead.
Signed-off-by: NJeff Layton <jeff.layton@primarydata.com>

Allow callers to pass in an inode instead of a filp.
Signed-off-by: NJeff Layton <jeff.layton@primarydata.com>
Reviewed-by: N"J. Bruce Fields" <bfields@fieldses.org>
Tested-by: N"J. Bruce Fields" <bfields@fieldses.org>

Commit 514ac99c "can: fix multiple delivery of a single CAN frame for
overlapping CAN filters" requires the skb->tstamp to be set to check for
identical CAN skbs.

Without timestamping to be required by user space applications this timestamp
was not generated which lead to commit 36c01245 "can: fix loss of CAN frames
in raw_rcv" - which forces the timestamp to be set in all CAN related skbuffs
by introducing several __net_timestamp() calls.

This forces e.g. out of tree drivers which are not using alloc_can{,fd}_skb()
to add __net_timestamp() after skbuff creation to prevent the frame loss fixed
in mainline Linux.

This patch removes the timestamp dependency and uses an atomic counter to
create an unique identifier together with the skbuff pointer.

Btw: the new skbcnt element introduced in struct can_skb_priv has to be
initialized with zero in out-of-tree drivers which are not using
alloc_can{,fd}_skb() too.
Signed-off-by: NOliver Hartkopp <socketcan@hartkopp.net>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: NMarc Kleine-Budde <mkl@pengutronix.de>

If there are no assigned devices, the guest PAT are not providing
any useful information and can be overridden to writeback; VMX
always does this because it has the "IPAT" bit in its extended
page table entries, but SVM does not have anything similar.
Hook into VFIO and legacy device assignment so that they
provide this information to KVM.
Reviewed-by: NAlex Williamson <alex.williamson@redhat.com>
Tested-by: NJoerg Roedel <jroedel@suse.de>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

NCM specs are not actually mandating a specific position in the frame for
the NDP (Network Datagram Pointer). However, some Huawei devices will
ignore our aggregates if it is not placed after the datagrams it points
to. Add support for doing just this, in a per-device configurable way.
While at it, update NCM subdrivers, disabling this functionality in all of
them, except in huawei_cdc_ncm where it is enabled instead.
We aren't making any distinction between different Huawei NCM devices,
based on what the vendor driver does. Standard NCM devices are left
unaffected: if they are compliant, they should be always usable, still
stay on the safe side.

This change has been tested and working with a Huawei E3131 device (which
works regardless of NDP position), a Huawei E3531 (also working both
ways) and an E3372 (which mandates NDP to be after indexed datagrams).

V1->V2:
- corrected wrong NDP acronym definition
- fixed possible NULL pointer dereference
- patch cleanup
V2->V3:
- Properly account for the NDP size when writing new packets to SKB
Signed-off-by: NEnrico Mioso <mrkiko.rs@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

e48453c3 ("block, cgroup: implement policy-specific per-blkcg
data") updated per-blkcg policy data to be dynamically allocated.
When a policy is registered, its policy data aren't created.  Instead,
when the policy is activated on a queue, the policy data are allocated
if there are blkg's (blkcg_gq's) which are attached to a given blkcg.
This is buggy.  Consider the following scenario.

1. A blkcg is created.  No blkg's attached yet.

2. The policy is registered.  No policy data is allocated.

3. The policy is activated on a queue.  As the above blkcg doesn't
   have any blkg's, it won't allocate the matching blkcg_policy_data.

4. An IO is issued from the blkcg and blkg is created and the blkcg
   still doesn't have the matching policy data allocated.

With cfq-iosched, this leads to an oops.

It also doesn't free policy data on policy unregistration assuming
that freeing of all policy data on blkcg destruction should take care
of it; however, this also is incorrect.

1. A blkcg has policy data.

2. The policy gets unregistered but the policy data remains.

3. Another policy gets registered on the same slot.

4. Later, the new policy tries to allocate policy data on the previous
   blkcg but the slot is already occupied and gets skipped.  The
   policy ends up operating on the policy data of the previous policy.

There's no reason to manage blkcg_policy_data lazily.  The reason we
do lazy allocation of blkg's is that the number of all possible blkg's
is the product of cgroups and block devices which can reach a
surprising level.  blkcg_policy_data is contrained by the number of
cgroups and shouldn't be a problem.

This patch makes blkcg_policy_data to be allocated for all existing
blkcg's on policy registration and freed on unregistration and removes
blkcg_policy_data handling from policy [de]activation paths.  This
makes that blkcg_policy_data are created and removed with the policy
they belong to and fixes the above described problems.
Signed-off-by: NTejun Heo <tj@kernel.org>
Fixes: e48453c3 ("block, cgroup: implement policy-specific per-blkcg data")
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Arianna Avanzini <avanzini.arianna@gmail.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

Add all_blkcgs list goes through blkcg->all_blkcgs_node and is
protected by blkcg_pol_mutex.  This will be used to fix
blkcg_policy_data allocation bug.
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Arianna Avanzini <avanzini.arianna@gmail.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

Grab a reference on a network namespace of the 'rbd map' (in case of
rbd) or 'mount' (in case of ceph) process and use that to open sockets
instead of always using init_net and bailing if network namespace is
anything but init_net.  Be careful to not share struct ceph_client
instances between different namespaces and don't add any code in the
!CONFIG_NET_NS case.

This is based on a patch from Hong Zhiguo <zhiguohong@tencent.com>.
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>
Reviewed-by: NSage Weil <sage@redhat.com>

All users gone. Remove it before we get another one.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

When a cpu goes up some architectures (e.g. x86) have to walk the irq
space to set up the vector space for the cpu. While this needs extra
protection at the architecture level we can avoid a few race
conditions by preventing the concurrent allocation/free of irq
descriptors and the associated data.

When a cpu goes down it moves the interrupts which are targeted to
this cpu away by reassigning the affinities. While this happens
interrupts can be allocated and freed, which opens a can of race
conditions in the code which reassignes the affinities because
interrupt descriptors might be freed underneath.

Example:

CPU1				CPU2
cpu_up/down
 irq_desc = irq_to_desc(irq);
				remove_from_radix_tree(desc);
 raw_spin_lock(&desc->lock);
				free(desc);

We could protect the irq descriptors with RCU, but that would require
a full tree change of all accesses to interrupt descriptors. But
fortunately these kind of race conditions are rather limited to a few
things like cpu hotplug. The normal setup/teardown is very well
serialized. So the simpler and obvious solution is:

Prevent allocation and freeing of interrupt descriptors accross cpu
hotplug.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Acked-by: NPeter Zijlstra <peterz@infradead.org>
Cc: xiao jin <jin.xiao@intel.com>
Cc: Joerg Roedel <jroedel@suse.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Yanmin Zhang <yanmin_zhang@linux.intel.com>
Link: http://lkml.kernel.org/r/20150705171102.063519515@linutronix.de

Commit 66507c7b ("mtd: nand: Add support to use nand_base
poi databuf as bounce buffer") added a flag NAND_USE_BOUNCE_BUFFER
using the same bit value as the existing NAND_BUSWIDTH_AUTO.

Cc: Kamal Dasu <kdasu.kdev@gmail.com>
Fixes: 66507c7b ("mtd: nand: Add support to use nand_base
	poi databuf as bounce buffer")
Signed-off-by: NScott Wood <scottwood@freescale.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

Making tick_broadcast_oneshot_control() independent from
CONFIG_GENERIC_CLOCKEVENTS_BROADCAST broke the build for
CONFIG_GENERIC_CLOCKEVENTS=n because the function is not defined
there.

Provide a proper stub inline.

Fixes: f32dd117 'tick/broadcast: Make idle check independent from mode and config'
Reported-by: Nkbuild test robot <fengguang.wu@intel.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Currently the broadcast busy check, which prevents the idle code from
going into deep idle, works only in one shot mode.

If NOHZ and HIGHRES are off (config or command line) there is no
sanity check at all, so under certain conditions cpus are allowed to
go into deep idle, where the local timer stops, and are not woken up
again because there is no broadcast timer installed or a hrtimer based
broadcast device is not evaluated.

Move tick_broadcast_oneshot_control() into the common code and provide
proper subfunctions for the various config combinations.

The common check in tick_broadcast_oneshot_control() is for the C3STOP
misfeature flag of the local clock event device. If its not set, idle
can proceed. If set, further checks are necessary.

Provide checks for the trivial cases:

 - If broadcast is disabled in the config, then return busy

 - If oneshot mode (NOHZ/HIGHES) is disabled in the config, return
   busy if the broadcast device is hrtimer based.

 - If oneshot mode is enabled in the config call the original
   tick_broadcast_oneshot_control() function. That function needs
   extra checks which will be implemented in seperate patches.

[ Split out from a larger combo patch ]
Reported-and-tested-by: NSudeep Holla <sudeep.holla@arm.com>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: Suzuki Poulose <Suzuki.Poulose@arm.com>
Cc: Lorenzo Pieralisi <Lorenzo.Pieralisi@arm.com>
Cc: Catalin Marinas <Catalin.Marinas@arm.com>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Preeti U Murthy <preeti@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Link: http://lkml.kernel.org/r/alpine.DEB.2.11.1507070929360.3916@nanos

Device drivers typically use ACPI _HIDs/_CIDs listed in struct device_driver
acpi_match_table to match devices. However, for generic drivers, we do not
want to list _HID for all supported devices. Also, certain classes of devices
do not have _CID (e.g. SATA, USB). Instead, we can leverage ACPI _CLS,
which specifies PCI-defined class code (i.e. base-class, subclass and
programming interface). This patch adds support for matching ACPI devices using
the _CLS method.

To support loadable module, current design uses _HID or _CID to match device's
modalias. With the new way of matching with _CLS this would requires modification
to the current ACPI modalias key to include _CLS. This patch appends PCI-defined
class-code to the existing ACPI modalias as following.

    acpi:<HID>:<CID1>:<CID2>:..:<CIDn>:<bbsspp>:
E.g:
    # cat /sys/devices/platform/AMDI0600:00/modalias
    acpi:AMDI0600:010601:

where bb is th base-class code, ss is te sub-class code, and pp is the
programming interface code

Since there would not be _HID/_CID in the ACPI matching table of the driver,
this patch adds a field to acpi_device_id to specify the matching _CLS.

    static const struct acpi_device_id ahci_acpi_match[] = {
        { ACPI_DEVICE_CLASS(PCI_CLASS_STORAGE_SATA_AHCI, 0xffffff) },
        {},
    };

In this case, the corresponded entry in modules.alias file would be:

    alias acpi*:010601:* ahci_platform
Acked-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: NHanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: NSuravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

This effectively reverts the following three commits:

 7bc10388 ACPI / resources: free memory on error in add_region_before()
 0f1b414d ACPI / PNP: Avoid conflicting resource reservations
 b9a5e5e1 ACPI / init: Fix the ordering of acpi_reserve_resources()

(commit b9a5e5e1 introduced regressions some of which, but not
all, were addressed by commit 0f1b414d and commit 7bc10388
was a fixup on top of the latter) and causes ACPI fixed hardware
resources to be reserved at the fs_initcall_sync stage of system
initialization.

The story is as follows.  First, a boot regression was reported due
to an apparent resource reservation ordering change after a commit
that shouldn't lead to such changes.  Investigation led to the
conclusion that the problem happened because acpi_reserve_resources()
was executed at the device_initcall() stage of system initialization
which wasn't strictly ordered with respect to driver initialization
(and with respect to the initialization of the pcieport driver in
particular), so a random change causing the device initcalls to be
run in a different order might break things.

The response to that was to attempt to run acpi_reserve_resources()
as soon as we knew that ACPI would be in use (commit b9a5e5e1).
However, that turned out to be too early, because it caused resource
reservations made by the PNP system driver to fail on at least one
system and that failure was addressed by commit 0f1b414d.

That fix still turned out to be insufficient, though, because
calling acpi_reserve_resources() before the fs_initcall stage of
system initialization caused a boot regression to happen on the
eCAFE EC-800-H20G/S netbook.  That meant that we only could call
acpi_reserve_resources() at the fs_initcall initialization stage
or later, but then we might just as well call it after the PNP
initalization in which case commit 0f1b414d wouldn't be
necessary any more.

For this reason, the changes made by commit 0f1b414d are reverted
(along with a memory leak fixup on top of that commit), the changes
made by commit b9a5e5e1 that went too far are reverted too and
acpi_reserve_resources() is changed into fs_initcall_sync, which
will cause it to be executed after the PNP subsystem initialization
(which is an fs_initcall) and before device initcalls (including
the pcieport driver initialization) which should avoid the initial
issue.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=100581
Link: http://marc.info/?t=143092384600002&r=1&w=2
Link: https://bugzilla.kernel.org/show_bug.cgi?id=99831
Link: http://marc.info/?t=143389402600001&r=1&w=2
Fixes: b9a5e5e1 "ACPI / init: Fix the ordering of acpi_reserve_resources()"
Reported-by: NRoland Dreier <roland@purestorage.com>
Cc: All applicable <stable@vger.kernel.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>

Modular users will always be users of init functionality, but
users of init functionality are not necessarily always modules.

Hence any functionality like module_init and module_exit would
be more at home in the module.h file.  And module.h should
explicitly include init.h to make the dependency clear.

We've already done all the legwork needed to ensure that this
move does not cause any build regressions due to implicit
header file include assumptions about where module_init lives.

Cc: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: NRusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>