Commit Graph

377885 Commits

Author SHA1 Message Date
Colin Cross
66df93b4c9 ion: don't use id 0 for handle cookie
ion userspace clients think that the cookie is a pointer, so they
use NULL to check if the handle has been initialized.  Set the first
id number to 1.

Change-Id: Ifb9af6029a8b08f57e41bc6160cc11e11001a2a9
Signed-off-by: Colin Cross <ccross@android.com>
2013-09-19 23:03:33 -05:00
Colin Cross
002119eeb2 ion: index client->handles rbtree by buffer
The only remaining users of the client->handles rbtree are
iterating through it like a list.  Keep the rbtree, but change
its index to be the buffer address instead of the handle address,
which makes ion_handle_lookup a fast rbtree search.

Change-Id: Ie7d974b3a5d9831c0d664de85ddae8db3c3abdf9
Signed-off-by: Colin Cross <ccross@android.com>
2013-09-19 23:03:33 -05:00
Colin Cross
1126d98d8e ion: replace userspace handle cookies with idr
Userspace handles should not leak kernel virtual addresses to
userspace.  They have to be validated by looking them up in an
rbtree anyways, so replace them with an idr and validate them
by using idr_find to convert the id number to the struct
ion_handle pointer.

Change-Id: Iab5667ba6f3a73256fec3949b23a9a6f8e14a283
Signed-off-by: Colin Cross <ccross@android.com>
2013-09-19 23:03:32 -05:00
Colin Cross
846b79b793 ion: remove IS_ERR_OR_NULL
IS_ERR_OR_NULL is often part of a bad pattern that can accidentally
return 0 on error:
if (IS_ERR_OR_NULL(ptr))
    return PTR_ERR(ptr);

It also usually means that the errors of a function are not well
defined.  Replace all uses in ion.c by ensure that the return
type of any function in ion is an ERR_PTR.

Specify that the expected return value from map_kernel or map_dma
heap ops is ERR_PTR, and warn if a heap returns NULL.

Change-Id: I6e7ea0d2e62fa08d4e372a7ef6da649f7a62289c
Signed-off-by: Colin Cross <ccross@android.com>
2013-09-19 23:03:32 -05:00
Colin Cross
d37aa151f8 ion: convert map_kernel to return ERR_PTR
ion is going to stop accepting NULL as an error value, use ERR_PTR.

Change-Id: I030e8b72138904e38a4a5d225beaaa98427651fb
Signed-off-by: Colin Cross <ccross@android.com>
2013-09-19 23:03:31 -05:00
Colin Cross
a3041cac9f ion: add free list size to heap debug files
Change-Id: I3c6309afdbd661a2f870fd1ba3fea9543e229882
Signed-off-by: Colin Cross <ccross@android.com>
2013-09-19 23:03:31 -05:00
Colin Cross
f526a55b40 ion: chunk_heap: fix leak in allocated counter
buffer->size is controlled by the outer ion layer, don't modify it
inside the heap.  Instead, compute the rounded up allocated size
on demand.

Change-Id: I288ffc1221ce96cfe2591468502ac3279065bde4
Signed-off-by: Colin Cross <ccross@android.com>
2013-09-19 23:03:30 -05:00
Colin Cross
6ebfe5864a mm: add a field to store names for private anonymous memory
Userspace processes often have multiple allocators that each do
anonymous mmaps to get memory.  When examining memory usage of
individual processes or systems as a whole, it is useful to be
able to break down the various heaps that were allocated by
each layer and examine their size, RSS, and physical memory
usage.

This patch adds a user pointer to the shared union in
vm_area_struct that points to a null terminated string inside
the user process containing a name for the vma.  vmas that
point to the same address will be merged, but vmas that
point to equivalent strings at different addresses will
not be merged.

Userspace can set the name for a region of memory by calling
prctl(PR_SET_VMA, PR_SET_VMA_ANON_NAME, start, len, (unsigned long)name);
Setting the name to NULL clears it.

The names of named anonymous vmas are shown in /proc/pid/maps
as [anon:<name>] and in /proc/pid/smaps in a new "Name" field
that is only present for named vmas.  If the userspace pointer
is no longer valid all or part of the name will be replaced
with "<fault>".

The idea to store a userspace pointer to reduce the complexity
within mm (at the expense of the complexity of reading
/proc/pid/mem) came from Dave Hansen.  This results in no
runtime overhead in the mm subsystem other than comparing
the anon_name pointers when considering vma merging.  The pointer
is stored in a union with fieds that are only used on file-backed
mappings, so it does not increase memory usage.

Change-Id: Ie2ffc0967d4ffe7ee4c70781313c7b00cf7e3092
Signed-off-by: Colin Cross <ccross@android.com>
2013-09-19 14:14:28 -05:00
Todd Poynor
b396b36a15 power_supply: kill android-battery driver
Discontinued in favor of future userspace charging helpers.

Change-Id: I840a94ff42e2219cfd8759f919f6188355a63d92
Signed-off-by: Todd Poynor <toddpoynor@google.com>
2013-09-19 13:55:39 -05:00
Rik van Riel
2f42fa9141 add extra free kbytes tunable
Add a userspace visible knob to tell the VM to keep an extra amount
of memory free, by increasing the gap between each zone's min and
low watermarks.

This is useful for realtime applications that call system
calls and have a bound on the number of allocations that happen
in any short time period.  In this application, extra_free_kbytes
would be left at an amount equal to or larger than than the
maximum number of allocations that happen in any burst.

It may also be useful to reduce the memory use of virtual
machines (temporarily?), in a way that does not cause memory
fragmentation like ballooning does.

[ccross]
Revived for use on old kernels where no other solution exists.
The tunable will be removed on kernels that do better at avoiding
direct reclaim.

Change-Id: I765a42be8e964bfd3e2886d1ca85a29d60c3bb3e
Signed-off-by: Rik van Riel<riel@redhat.com>
Signed-off-by: Colin Cross <ccross@android.com>
2013-09-19 13:53:19 -05:00
Rebecca Schultz Zavin
bbf5538ee0 gpu: ion: Fix performance issue in faulting code
Previously the code to fault ion buffers in one page at a time had a
performance problem caused by the requirement to traverse the sg list
looking for the right page to load in (a result of the fact that the items in
the list may not be of uniform size).  To fix the problem, for buffers
that will be faulted in, also keep a flat array of all the pages in the buffer
to use from the fault handler.  To recover some of the additional memory
footprint this creates per buffer, dirty bits used to indicate which
pages have been faulted in to the cpu are now stored in the low bit of each
page struct pointer in the page array.

Change-Id: I891b077dc0c88ed6d416b256626d8778fd67be84
Signed-off-by: Rebecca Schultz Zavin <rebecca@android.com>
2013-09-19 13:50:13 -05:00
Benjamin Gaignard
ae2b22e9b7 gpu: ion: add CMA heap
New heap type ION_HEAP_TYPE_DMA where allocation is done with dma_alloc_coherent API.
device coherent_dma_mask must be set to DMA_BIT_MASK(32).
ion_platform_heap private field is used to retrieve the device linked to CMA,
if NULL the default CMA area is used.
ion_cma_get_sgtable is a copy of dma_common_get_sgtable function which should
be in kernel 3.5

Change-Id: If4b1a3f9c8a6bd72053226208832f4971e44372f
Signed-off-by: Benjamin Gaignard <benjamin.gaignard@linaro.org>
2013-09-19 13:50:05 -05:00
Benjamin Gaignard
0a87e75ab5 gpu: ion: fix ion_platform_data definition
fix ion_platform_heap to make is use an usual way in board configuration file.

Signed-off-by: Benjamin Gaignard <benjamin.gaignard@linaro.org>
2013-09-19 13:50:05 -05:00
Todd Poynor
c471519408 ARM: kgdb: ignore breakpoint instructions from user mode
Avoid conflicts with user mode usage of the same instructions, as with
Clang -ftrapv.

Change-Id: I12d1c6d8f94376bfd2503cb0be843d7e478fb6ea
Signed-off-by: Todd Poynor <toddpoynor@google.com>
2013-09-19 13:50:04 -05:00
Arve Hjønnevåg
a88f9e2749 kconfig: Fix defconfig when one choice menu selects options that another choice menu depends on
The defconfig and Kconfig combination below, which is based on 3.10-rc4
Kconfigs, resulted in several options getting set to "m" instead of "y".

defconfig:
---
CONFIG_MODULES=y
CONFIG_USB_GADGET=y
CONFIG_USB_ZERO=y
---

Kconfig:
---
menuconfig MODULES
	bool "Enable loadable module support"

config CONFIGFS_FS
	tristate "Userspace-driven configuration filesystem"

config OCFS2_FS
        tristate "OCFS2 file system support"
        depends on CONFIGFS_FS
        select CRC32

config USB_LIBCOMPOSITE
	tristate
	select CONFIGFS_FS

choice
	tristate "USB Gadget Drivers"
	default USB_ETH

config USB_ZERO
	tristate "Gadget Zero (DEVELOPMENT)"
	select USB_LIBCOMPOSITE

config USB_ETH
	tristate "Ethernet Gadget (with CDC Ethernet support)"
	select USB_LIBCOMPOSITE

endchoice

config CRC32
        tristate "CRC32/CRC32c functions"
        default y

choice
        prompt "CRC32 implementation"
        depends on CRC32
        default CRC32_SLICEBY8

config CRC32_SLICEBY8
        bool "Slice by 8 bytes"

endchoice

---

Signed-off-by: Arve Hjønnevåg <arve@android.com>
2013-07-01 15:52:05 -07:00
Arve Hjønnevåg
21dd5d7718 netfilter: xt_qtaguid: 3.10 fixes
Stop using obsolete procfs api.

Signed-off-by: Arve Hjønnevåg <arve@android.com>
2013-07-01 15:52:04 -07:00
Arve Hjønnevåg
6908fe248f misc: uidstat: Remove use of obsolete create_proc_read_entry api
Signed-off-by: Arve Hjønnevåg <arve@android.com>
2013-07-01 15:52:03 -07:00
Arve Hjønnevåg
73570fe76d netfilter: xt_quota2: 3.10 fixes.
- Stop using obsolete create_proc_entry api.
- Use proc_set_user instead of directly accessing the private structure.

Signed-off-by: Arve Hjønnevåg <arve@android.com>
2013-07-01 15:52:03 -07:00
Arve Hjønnevåg
4af1c50c2b net: activity_stats: Stop using obsolete create_proc_read_entry api
Convert to use seq_read

Signed-off-by: Arve Hjønnevåg <arve@android.com>
2013-07-01 15:52:02 -07:00
John Stultz
bbba041b12 pstore: Update Documentation/android.txt
Update Documentation/android.txt to reference PSTORE_CONSOLE
and PSTORE_RAM instead of ANDROID_RAM_CONSOLE

Change-Id: I2c56e73f8c65c3ddbe6ddbf1faadfacb42a09575
Reported-by: Jon Medhurst (Tixy) <tixy@linaro.org>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2013-07-01 15:52:01 -07:00
Jon Medhurst (Tixy)
7a8ab31b78 ARM: mm: Allow an empty PMD in alloc_init_pte()
The Android patch titled "ARM: allow the kernel text section to
be made read-only" modifies alloc_init_pte() and adds a BUG_ON
to detect the case where a section mapping is being overwritten.
However the test doesn't allow for the legitimate case where the
PMD is empty, as can happen for kernels built with CONFIG_ARM_LPAE.
So extend the test to allow this.

Change-Id: I28eeaefd856bae63a5532980e41e0fd4d8922e79
Signed-off-by: Jon Medhurst <tixy@linaro.org>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2013-07-01 15:52:01 -07:00
John Stultz
22eee1aaff mmc: core: Remove stray CONFIG_EXPERIMENTAL dependencies
CONFIG_EXPERIMENTAL has been removed from the kernel, so clean
up its use in MMC_EMBEDDED_SDIO and MMC_PARANOID_SD_INIT options.

Change-Id: If414c265134b36740a84564274a631803c8e81b4
Cc: Arve Hjønnevåg <arve@android.com>
Cc: San Mehat <san@google.com>
Cc: Android Kernel Team <kernel-team@android.com>
Reported-by: Jon Medhurst (Tixy) <tixy@linaro.org>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2013-07-01 15:52:00 -07:00
John Stultz
eec9efad85 ion: Add Kconfig dependency to ARM
The ion code has some very specific arm-isms which keeps it
from building on other architectures. These should probably be
resolved, but in the mean time, add a dependency on CONFIG_ARM
to avoid build failures.

v2: Fix earlier flub, sending out an early untested version of
the patch.

Change-Id: I5979af1ad59d1eeddd9e08763b1cbc946cf82339
Cc: Arve Hjønnevåg <arve@android.com>
Cc: Rebecca Schultz Zavin <rebecca@android.com>
Cc: Android Kernel Team <kernel-team@android.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2013-07-01 15:52:00 -07:00
John Stultz
a657646035 selinux: binder: Fix COMMON_AUDIT_DATA_INIT compile issue
The COMMON_AUDIT_DATA_INIT macros have been removed, and are
now replaced with open coded ad.type initialization.

Thus, this patch updates the selinux_binder_transfer_file function
so it builds.

Change-Id: Ide41069a87638e294899768d09302f4013794e4c
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Arve Hjønnevåg <arve@android.com>
Cc: Android Kernel Team <kernel-team@android.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
2013-07-01 15:51:59 -07:00
JP Abgrall
24d852635b netfilter: xt_qtaguid: fix bad tcp_time_wait sock handling
Since (41063e9 ipv4: Early TCP socket demux), skb's can have an sk which
is not a struct sock but the smaller struct inet_timewait_sock without an
sk->sk_socket. Now we bypass sk_state == TCP_TIME_WAIT

Signed-off-by: JP Abgrall <jpa@google.com>
2013-07-01 15:51:58 -07:00
Arve Hjønnevåg
cbce650376 usb: gadget: android: 3.10 fixes
Signed-off-by: Arve Hjønnevåg <arve@android.com>
2013-07-01 15:51:58 -07:00
Arve Hjønnevåg
8483afe9dd usb: gadget: android: move init to late_initcall for now
gserial_alloc_line crashes when called from module_init

Signed-off-by: Arve Hjønnevåg <arve@android.com>
2013-07-01 15:51:57 -07:00
Arve Hjønnevåg
bdc4b52583 usb: gadget: android: Fixes and hacks to make android usb gadget compile on 3.9
Signed-off-by: Arve Hjønnevåg <arve@android.com>
2013-07-01 15:51:56 -07:00
Benoit Goby
de8cff675b usb: gadget: Fix android gadget driver build
Removed obsolete f_adb function

Change-Id: Idfb4110429bc0ea63f493c68ad667f49ca471987
Signed-off-by: Benoit Goby <benoit@android.com>
2013-07-01 15:51:56 -07:00
Benoit Goby
b94f8f691c HACK: usb: gadget: Fix enumeration on boot
The Android gadget driver disconnects the gadget on bind
and expects the gadget to stay disconnected until it calls
usb_gadget_connect when userspace is ready. Removed the call
to usb_gadget_connect in usb_gadget_probe_driver to avoid
enabling the pullup before userspace is ready.

Change-Id: I63707ac6e16a44eca52351a4bf80407d25fbd35e
Signed-off-by: Benoit Goby <benoit@android.com>
2013-07-01 15:51:55 -07:00
Arve Hjønnevåg
766a5bfa1e usb: gadget: android: Fixes and hacks to make android usb gadget compile on 3.8
Signed-off-by: Arve Hjønnevåg <arve@android.com>
2013-07-01 15:51:54 -07:00
Arve Hjønnevåg
6c6f573eb2 ARM: decompressor: Flush tlb before swiching domain 0 to client mode
If the bootloader used a page table that is incompatible with domain 0
in client mode, and boots with the mmu on, then swithing domain 0 to
client mode causes a fault if we don't flush the tlb after updating
the page table pointer.

v2: Add ISB before loading dacr.

Signed-off-by: Arve Hjønnevåg <arve@android.com>
2013-07-01 15:51:53 -07:00
Arve Hjønnevåg
4ee50207d6 ARM: mm: Split memory banks that span multiple sections when sparsemem is enabled
This fixes a crash in mem_init which assumes all pages in a memory bank
are part of the same page array.

Signed-off-by: Arve Hjønnevåg <arve@android.com>
2013-07-01 15:51:53 -07:00
Arve Hjønnevåg
62f59056d4 mmc: block: Remove call to mmc_blk_set_blksize
It no longer exists.

Signed-off-by: Arve Hjønnevåg <arve@android.com>
2013-07-01 15:51:52 -07:00
Arve Hjønnevåg
9d168cf9d7 gpu: ion: Remove __GFP_NO_KSWAPD
It no longer exists.

Signed-off-by: Arve Hjønnevåg <arve@android.com>
2013-07-01 15:51:52 -07:00
Arve Hjønnevåg
3bb28260e4 gpu: ion: __dma_page_cpu_to_dev -> arm_dma_ops.sync_single_for_device hack
Signed-off-by: Arve Hjønnevåg <arve@android.com>
2013-07-01 15:51:51 -07:00
Arve Hjønnevåg
4b45590624 ARM: fiq_debugger: Update tty code for 3.9
Signed-off-by: Arve Hjønnevåg <arve@android.com>
2013-07-01 15:51:50 -07:00
Arve Hjønnevåg
c2b48c1f48 ARM: fiq_debugger: Use kmsg_dumper to dump kernel logs
Signed-off-by: Arve Hjønnevåg <arve@android.com>
2013-07-01 15:51:50 -07:00
Arve Hjønnevåg
4c1faac6ac ARM: fiq_debugger: Fix to compile on 3.7
Use for_each_irq_desc in arch/arm/common/fiq_debugger.c

Signed-off-by: Arve Hjønnevåg <arve@android.com>
2013-07-01 15:51:49 -07:00
Arve Hjønnevåg
5f08b153be usb: otg: otg-wakelock: Fix build for 3.7
Signed-off-by: Arve Hjønnevåg <arve@android.com>
2013-07-01 15:51:48 -07:00
Lianwei Wang
37a05ab72b cpufreq: interactive: resched timer if max freq raised
When the policy max freq is raised, and before the timer is
rescheduled in idle callback, the cpu freq may stuck at a
lower freq.

The target_freq shall be updated too, else on a high load
situation, the new_freq is always equal to target_freq and
which will cause freq stuck at a lower freq too.

Reschedule the timer on gov limits callback.

Change-Id: I6c187001ab43e859731429b64f75a74eebc37a24
Signed-off-by: Lianwei Wang <a22439@motorola.com>
2013-07-01 15:46:29 -07:00
Lianwei Wang
e1fb7646f1 cpufreq: interactive: fix race on cpufreq TRANSITION notifier
The cpufreq TRANSTION notifier callback does not check the
governor_enabled state on affected CPUS, which will case
kernel panic in update_load because the policy object maybe
NULL or invalid when governor_enabled is false.

Change-Id: Ie0f1718124f61e2f9b5da57abc6981ada5b83908
Signed-off-by: Lianwei Wang <a22439@motorola.com>
2013-07-01 15:46:28 -07:00
Colin Cross
1dc1499a43 af_unix: use freezable blocking calls in read
Avoid waking up every thread sleeping in read call on an AF_UNIX
socket during suspend and resume by calling a freezable blocking
call.  Previous patches modified the freezer to avoid sending
wakeups to threads that are blocked in freezable blocking calls.

This call was selected to be converted to a freezable call because
it doesn't hold any locks or release any resources when interrupted
that might be needed by another freezing task or a kernel driver
during suspend, and is a common site where idle userspace tasks are
blocked.

Change-Id: I788246a76780ea892659526e70be018b18f646c4
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Colin Cross <ccross@android.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-07-01 15:46:26 -07:00
Colin Cross
e85cba35b3 sigtimedwait: use freezable blocking call
Avoid waking up every thread sleeping in a sigtimedwait call during
suspend and resume by calling a freezable blocking call.  Previous
patches modified the freezer to avoid sending wakeups to threads
that are blocked in freezable blocking calls.

This call was selected to be converted to a freezable call because
it doesn't hold any locks or release any resources when interrupted
that might be needed by another freezing task or a kernel driver
during suspend, and is a common site where idle userspace tasks are
blocked.

Change-Id: Ic27469b60a67d50cdc0d0c78975951a99c25adcd
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Colin Cross <ccross@android.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-07-01 15:46:24 -07:00
Colin Cross
98009ee43a nanosleep: use freezable blocking call
Avoid waking up every thread sleeping in a nanosleep call during
suspend and resume by calling a freezable blocking call.  Previous
patches modified the freezer to avoid sending wakeups to threads
that are blocked in freezable blocking calls.

This call was selected to be converted to a freezable call because
it doesn't hold any locks or release any resources when interrupted
that might be needed by another freezing task or a kernel driver
during suspend, and is a common site where idle userspace tasks are
blocked.

Change-Id: I93383201d4dd62130cd9a9153842d303fc2e2986
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Colin Cross <ccross@android.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-07-01 15:46:23 -07:00
Colin Cross
5ccf7dfeea futex: use freezable blocking call
Avoid waking up every thread sleeping in a futex_wait call during
suspend and resume by calling a freezable blocking call.  Previous
patches modified the freezer to avoid sending wakeups to threads
that are blocked in freezable blocking calls.

This call was selected to be converted to a freezable call because
it doesn't hold any locks or release any resources when interrupted
that might be needed by another freezing task or a kernel driver
during suspend, and is a common site where idle userspace tasks are
blocked.

Change-Id: I9ccab9c2d201adb66c85432801cdcf43fc91e94f
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Darren Hart <dvhart@linux.intel.com>
Signed-off-by: Colin Cross <ccross@android.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-07-01 15:46:16 -07:00
Colin Cross
947377f9be select: use freezable blocking call
Avoid waking up every thread sleeping in a select call during
suspend and resume by calling a freezable blocking call.  Previous
patches modified the freezer to avoid sending wakeups to threads
that are blocked in freezable blocking calls.

This call was selected to be converted to a freezable call because
it doesn't hold any locks or release any resources when interrupted
that might be needed by another freezing task or a kernel driver
during suspend, and is a common site where idle userspace tasks are
blocked.

Change-Id: I0d7565ec0b6bc5d44cb55f958589c56e6bd16348
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Colin Cross <ccross@android.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-07-01 15:45:28 -07:00
Colin Cross
8f02557bee epoll: use freezable blocking call
Avoid waking up every thread sleeping in an epoll_wait call during
suspend and resume by calling a freezable blocking call.  Previous
patches modified the freezer to avoid sending wakeups to threads
that are blocked in freezable blocking calls.

This call was selected to be converted to a freezable call because
it doesn't hold any locks or release any resources when interrupted
that might be needed by another freezing task or a kernel driver
during suspend, and is a common site where idle userspace tasks are
blocked.

Change-Id: I848d08d28c89302fd42bbbdfa76489a474ab27bf
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Colin Cross <ccross@android.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-07-01 15:44:19 -07:00
Colin Cross
a7173a0d11 binder: use freezable blocking calls
Avoid waking up every thread sleeping in a binder call during
suspend and resume by calling a freezable blocking call.  Previous
patches modified the freezer to avoid sending wakeups to threads
that are blocked in freezable blocking calls.

This call was selected to be converted to a freezable call because
it doesn't hold any locks or release any resources when interrupted
that might be needed by another freezing task or a kernel driver
during suspend, and is a common site where idle userspace tasks are
blocked.

Change-Id: Ic4458ae90447f6caa895cc62f08e515caa7790ba
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Colin Cross <ccross@android.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-07-01 15:44:18 -07:00
Colin Cross
f8323ee486 freezer: add new freezable helpers using freezer_do_not_count()
Freezing tasks will wake up almost every userspace task from
where it is blocking and force it to run until it hits a
call to try_to_sleep(), generally on the exit path from the syscall
it is blocking in.  On resume each task will run again, usually
restarting the syscall and running until it hits the same
blocking call as it was originally blocked in.

To allow tasks to avoid running on every suspend/resume cycle,
this patch adds additional freezable wrappers around blocking calls
that call freezer_do_not_count().  Combined with the previous patch,
these tasks will not run during suspend or resume unless they wake
up for another reason, in which case they will run until they hit
the try_to_freeze() in freezer_count(), and then continue processing
the wakeup after tasks are thawed.

Additional patches will convert the most common locations that
userspace blocks in to use freezable helpers.

Change-Id: Id909760ce460f2532801a4b00d344f0816bfefc9
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Colin Cross <ccross@android.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-07-01 15:44:16 -07:00