This adds support to allow asm/ptrace.h to define two new macros,
arch_ptrace_stop_needed and arch_ptrace_stop. These control special
machine-specific actions to be done before a ptrace stop. The new code
compiles away to nothing when the new macros are not defined. This is the
case on all machines to begin with.
On ia64, these macros will be defined to solve the long-standing issue of
ptrace vs register backing store.
Signed-off-by: Roland McGrath <roland@redhat.com>
Cc: Petr Tesarik <ptesarik@suse.cz>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Matthew Wilcox <willy@debian.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
I couldn't find any users, so removing it..
Signed-off-by: Daniel Walker <dwalker@mvista.com>
Cc: Karsten Keil <kkeil@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
I couldn't find any users, so removing it..
Signed-off-by: Daniel Walker <dwalker@mvista.com>
Acked-by: Alan Cox <alan@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The rcu_assign_pointer() primitive currently unconditionally executes a
memory barrier, even when a NULL pointer is being assigned. This has lead
some to avoid using rcu_assign_pointer() for NULL pointers, which loses the
self-documenting advantages of rcu_assign_pointer() This patch uses
__builtin_const_p() to omit needless memory barriers for NULL-pointer
assignments at compile time with no runtime penalty, as discussed in the
following thread:
http://www.mail-archive.com/netdev@vger.kernel.org/msg54852.html
Tested on x86_64 and ppc64, also compiled the four cases (NULL/non-NULL
and const/non-const) with gcc version 4.1.2, and hand-checked the
assembly output.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
NR_OPEN (historically set to 1024*1024) actually forbids processes to open
more than 1024*1024 handles.
Unfortunatly some production servers hit the not so 'ridiculously high
value' of 1024*1024 file descriptors per process.
Changing NR_OPEN is not considered safe because of vmalloc space potential
exhaust.
This patch introduces a new sysctl (/proc/sys/fs/nr_open) wich defaults to
1024*1024, so that admins can decide to change this limit if their workload
needs it.
[akpm@linux-foundation.org: export it for sparc64]
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently, no notification event has been sent when inode's link count
changed. This is inconvenient for the application in some cases:
Suppose you have the following directory structure
foo/test
bar/
and you watch test. If someone does "mv foo/test bar/", you get event
IN_MOVE_SELF and you know something has happened with the file "test".
However if someone does "ln foo/test bar/test" and "rm foo/test" you get no
inotify event for the file "test" (only directories "foo" and "bar" receive
events).
Furthermore it could be argued that link count belongs to file's metadata and
thus IN_ATTRIB should be sent when it changes.
The following patch implements sending of IN_ATTRIB inotify events when link
count of the inode changes, i.e., when a hardlink to the inode is created or
when it is removed. This event is sent in addition to all the events sent so
far. In particular, when a last link to a file is removed, IN_ATTRIB event is
sent in addition to IN_DELETE_SELF event.
Signed-off-by: Jan Kara <jack@suse.cz>
Acked-by: Morten Welinder <mwelinder@gmail.com>
Cc: Robert Love <rlove@google.com>
Cc: John McCutchan <ttb@tentacle.dhs.org>
Cc: Steven French <sfrench@us.ibm.com>
Cc: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Use list_for_each_entry_reverse for super_blocks list and remove
unused sb_entry macro.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
I was happy to discover the brand new IS_ALIGN macro and quickly used it in
my code. To my dismay I found that the generated code used division to
perform the test.
This patch fixes it by changing the % test to an &. This avoids the
division.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Instead of allocating a fix sized array of NR_CPUS pointers for percpu_data,
we can use nr_cpu_ids, which is generally < NR_CPUS.
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Cc: Christoph Lameter <clameter@sgi.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
After some archeology (see http://logfs.org/logfs/inode_state_bits) I
finally figured out what the three I_DIRTY bits do. Maybe others would
prefer less effort to reach this insight.
Signed-off-by: Joern Engel <joern@logfs.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Given a number of places in the tree that need to calculate this value
explicitly, might as well just create a macro for it.
(akpm: must be implemented as a macro for callee typeof() usage)
Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add a proper prototype for vty_init() in include/linux/vt_kern.h
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ad a proper prototype for migration_init() in include/linux/fs.h
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add a proper prototype for signals_init() in include/linux/signal.h
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- All implementations can be __devinit
- The function prototypes were in asm/timex.h but they all must be the same,
so create a single declaration in linux/timex.h.
- uninline the sparc64 version to match the other architectures
- Don't bother #defining ARCH_HAS_READ_CURRENT_TIMER to a particular value.
[ezk@cs.sunysb.edu: fix build]
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Haavard Skinnemoen <hskinnemoen@atmel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch contains the scheduled removal of OSS drivers whose config
options have been removed in 2.6.23.
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add a proper prototype for show_interrupts() in include/linux/interrupt.h
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This allows a flag to be set on loop devices so that when they are
closed for the last time, they'll self-destruct.
In general, so that we can automatically allocate loop devices (as with
losetup -f) and have them disappear when we're done with them.
In particular, right now, so that we can stop relying on the hackish
special-case in umount(8) which kills off loop devices which were set up by
'mount -oloop'. That means we can stop putting crap in /etc/mtab which
doesn't belong there, which means it can be a symlink to /proc/mounts, which
means yet another writable file on the root filesystem is eliminated and the
'stateless' folks get happier... and OLPC trac #356 can be closed.
The mount(8) side of that is at
http://marc.info/?l=util-linux-ng&m=119362955431694&w=2
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Cc: Bernardo Innocenti <bernie@codewiz.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The 32-bit version is more efficient (and apparently gives better hash
results than the 64-bit version), so users who are only hashing a 32-bit
quantity can now opt to use the 32-bit version explicitly, rather than
promoting to a long.
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Cc: William Lee Irwin III <wli@holomorphy.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The source and destination addresses are included to allow channel
selection based on address alignment.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
Pass a full set of flags to drivers' per-operation 'prep' routines.
Currently the only flag passed is DMA_PREP_INTERRUPT. The expectation is
that arch-specific async_tx_find_channel() implementations can exploit this
capability to find the best channel for an operation.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Shannon Nelson <shannon.nelson@intel.com>
Reviewed-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
The tx_set_src and tx_set_dest methods were originally implemented to allow
an array of addresses to be passed down from async_xor to the dmaengine
driver while minimizing stack overhead. Removing these methods allows
drivers to have all transaction parameters available at 'prep' time, saves
two function pointers in struct dma_async_tx_descriptor, and reduces the
number of indirect branches..
A consequence of moving this data to the 'prep' routine is that
multi-source routines like async_xor need temporary storage to convert an
array of linear addresses into an array of dma addresses. In order to keep
the same stack footprint of the previous implementation the input array is
reused as storage for the dma addresses. This requires that
sizeof(dma_addr_t) be less than or equal to sizeof(void *). As a
consequence CONFIG_DMADEVICES now depends on !CONFIG_HIGHMEM64G. It also
requires that drivers be able to make descriptor resources available when
the 'prep' routine is polled.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Shannon Nelson <shannon.nelson@intel.com>
Remove the unused ASYNC_TX_ASSUME_COHERENT flag. Async_tx is
meant to hide the difference between asynchronous hardware and synchronous
software operations, this flag requires clients to understand cache
coherency consequences of the async path.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
qc->n_iter was used for libata's own sg walking before sg chaining
replaced it. During conversion, the field and its usage in sata_fsl
were left behind. Kill the filed and update sata_fsl.
tj: This was part of James's libata-use-block-layer-padding patch.
Separated out by me.
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: Li Yang <leoli@freescale.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Marvell's Orion SoC includes SATA controllers based on Marvell's
PCI-to-SATA 88SX controllers. This patch extends the libATA sata_mv
driver to support those controllers.
[edited to use linux/ata_platform.h -jg]
Signed-off-by: Saeed Bishara <saeed@marvell.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Iterating through a device node's parents is simple enough, but dealing
with the refcounts properly is a little ugly, and replicating that logic
is asking for someone to get it wrong or forget it all together, eg:
while (dn != NULL) {
/* loop body */
tmp = of_get_parent(dn);
of_node_put(dn);
dn = tmp;
}
So add of_get_next_parent(), inspired by of_get_next_child(). The
contract is that it returns the parent and drops the reference on the
current node, this makes the loop look like:
while (dn != NULL) {
/* loop body */
dn = of_get_next_parent(dn);
}
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Paul Mackerras <paulus@samba.org>
egrep serial /proc/acpi/battery/BAT0/info
serial number: 32090
serial number can tell you from the imminent danger
of beeing set on fire.
Signed-off-by: maximilian attems <max@stro.at>
Acked-by: Alexey Starikovskiy <astarikovskiy@suse.de>
Signed-off-by: Len Brown <len.brown@intel.com>
ide-cris.c:
* Add cris_setup_ports() helper and use it instead of ide_setup_ports()
(fixes random value being set in ->io_ports[IDE_IRQ_OFFSET]).
buddha.c:
* Add buddha_setup_ports() helper and use it instead of ide_setup_ports().
falconide.c:
* Add falconide_setup_ports() helper and use it instead of ide_setup_ports(),
also fix return value of falconide_init() while at it.
gayle.c:
* Add gayle_setup_ports() helper and use it instead of ide_setup_ports().
macide.c:
* Add macide_setup_ports() helper and use it instead of ide_setup_ports()
(fixes incorrect value being set in ->io_ports[IDE_IRQ_OFFSET]).
q40ide.c:
* Fix q40_ide_setup_ports() comments.
ide.c:
* Remove no longer needed ide_setup_ports().
Cc: Mikael Starvik <starvik@axis.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
This is Palmchip BK3710 IDE controller support.
The IDE controller logic supports PIO, MultiWord-DMA and Ultra-DMA modes.
Supports interface to Compact Flash (CF) configured in True-IDE mode.
Bart:
- remove dead code
- fix ide_hwif_setup_dma() build problem
Signed-off-by: Anton Salnikov <asalnikov@ru.mvista.com>
Reviewed-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Reviewed-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Required by next patch to use it from the flow classifier.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
The following is an implementation of the Windows Management
Instrumentation (WMI) ACPI interface mapper (PNP0C14).
What it does:
Parses the _WDG method and exports functions to process WMI method calls,
data block query/ set commands (both based on GUID) and does basic event
handling.
How: WMI presents an in kernel interface here (essentially, a minimal
wrapper around ACPI)
(const char *guid assume the 36 character ASCII representation of
a GUID - e.g. 67C3371D-95A3-4C37-BB61-DD47B491DAAB)
wmi_evaluate_method(const char *guid, u8 instance, u32 method_id,
const struct acpi_buffer *in, struct acpi_buffer *out)
wmi_query_block(const char *guid, u8 instance,
struct acpi_buffer *out)
wmi_set_block(const char *guid, u38 instance,
const struct acpi_buffer *in)
wmi_install_notify_handler(acpi_notify_handler handler);
wmi_remove_notify_handler(void);
wmi_get_event_data(u32 event, struct acpi_buffer *out)
wmi_has_guid(const char guid*)
wmi_has_guid() is a helper function to find if a GUID exists or not on the
system (a quick and easy way for WMI dependant drivers to see if the
the method/ block they want exists, since GUIDs are supposed to be unique).
Event handling - allow a WMI based driver to register a notifier handler
for each GUID with WMI. When a notification is sent to a GUID in WMI, the
handler registered with WMI is then called (it is left to the caller to
ask for the WMI event data associated with the GUID, if needed).
What it won't do:
Unicode - The MS article[1] calls for converting between ASCII and Unicode (or
vice versa) if a GUID is marked as "string". This is left up to the calling
driver.
Handle a MOF[1] - the WMI mapper just exports methods, data and events to
userspace. MOF handling is down to userspace.
Userspace interface - this will be added later.
[1] http://www.microsoft.com/whdc/system/pnppwr/wmi/wmi-acpi.mspx
===
ChangeLog
==
v1 (2007-10-02):
* Initial release
v2 (2007-10-05):
* Cleaned up code - split up super "wmi_evaluate_block" -> each external
symbol now handles its own ACPI calls, rather than handing off to
a "super" method (and in turn, is a lot simpler to read)
* Added a find_guid() symbol - return true if a given GUID exists on
the system
* wmi_* functions now return type acpi_status (since they are just
fancy wrappers around acpi_evaluate_object())
* Removed extra debug code
v3 (2007-10-27)
* More code clean up - now passes checkpatch.pl
* Change data block calls - ref MS spec, method ID is not required for
them, so drop it from the function parameters.
* Const'ify guid in the function call parameters.
* Fix _WDG buffer handling - copy the data to our own private structure.
* Change WMI from tristate to bool - otherwise the external functions are
not exported in linux/acpi.h if you try to build WMI as a module.
* Fix more flag comparisons.
* Add a maintainers entry - since I wrote this, I should take the blame
for it.
v4 (2007-10-30)
* Add missing brace from after fixing checkpatch errors.
* Rewrote event handling - allow external drivers to register with WMI to
handle WMI events
* Clean up flags and sanitise flag handling
v5 (2007-11-03)
* Add sysfs interface for userspace. Export events over netlink again.
* Remove module left overs, fully convert to built-in driver.
* Tweak in-kernel API to use u8 for instance, since this is what the GUID
blocks use (so instance cannot be greater than u8).
* Export wmi_get_event_data() for in kernel WMI drivers.
v6 (2007-11-07)
* Split out userspace into a different patch
v7 (2007-11-20)
* Fix driver to handle multiple PNP0C14 devices - store all GUIDs using
the kernel's built in list functions, and just keep adding to the list
every time we handle a PNP0C14 devices - GUIDs will always be unique,
and WMI callers do not know or care about different devices.
* Change WMI event handler registration to use its' own event handling
struct; we should not pass an acpi_handle down to any WMI based drivers
- they should be able to function with only the calls provided in WMI.
* Update my e-mail address
v8 (2007-11-28)
* Convert back to a module.
* Update Kconfig to default to building as a module.
* Remove an erroneous printk.
* Simply comments for string flag (since we now leave the handling to the
caller).
v9 (2007-12-07)
* Add back missing MODULE_DEVICE_TABLE for autoloading
* Checkpatch fixes
v10 (2007-12-12)
* Workaround broken GUIDs declared expensive without a WCxx method.
* Minor cleanups
v11 (2007-12-17)
* More fixing for broken GUIDs declared expensive without a WCxx method.
* Add basic EmbeddedControl region handling.
v12 (2007-12-18)
* Changed EC region handling code, as per Alexey's comments.
v13 (2007-12-27)
* Changed event handling so that we can have one event handler registered
per GUID, as per Matthew Garrett's suggestion.
v14 (2008-01-12)
* Remove ACPI debug statements
v15 (2008-02-01)
* Replace two remaining 'x == NULL' type tests with '!x'
v16 (2008-02-05)
* Change MAINTAINERS entry, as I am not, and never have been, paid to work
on WMI
* Remove 'default' line from Kconfig
Signed-off-by: Carlos Corbacho <carlos@strangeworlds.co.uk>
CC: Matthew Garrett <mjg59@srcf.ucam.org>
CC: Alexey Starikovskiy <aystarik@gmail.com>
Signed-off-by: Len Brown <len.brown@intel.com>
m68k allmodconfig gives
drivers/net/wireless/b43/main.c:251: error: implicit declaration of function 'mmiowb'
because CONFIG_B43=m, CONFIG_SSB_PCIHOST=n.
Might be Kconfig bustage, but this works...
Cc: Michael Buesch <mb@bu3sch.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
* 'agp-patches' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/agp-2.6:
agp: remove flush_agp_mappings calls from new flush handling code
intel-agp: introduce IS_I915 and do some cleanups..
[intel_agp] fix name for G35 chipset
intel-agp: fixup resource handling in flush code.
intel-agp: add new chipset ID
agp: remove unnecessary pci_dev_put
agp: remove uid comparison as security check
fix AGP warning
agp/intel: Add chipset flushing support for i8xx chipsets.
intel-agp: add chipset flushing support
agp: add chipset flushing support to AGP interface
Add some new card definitions and fix a typo (from Eugen Paiuc).
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Make it possible to unregister a led classdev object in a safe way during a
suspend/resume cycle.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Michael Buesch <mb@bu3sch.de>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: "John W. Linville" <linville@tuxdriver.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Len Brown <lenb@kernel.org>
Cc: Greg KH <greg@kroah.com>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Make it possible to unregister a Hardware Random Number Generator
device object in a safe way during a suspend/resume cycle.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Michael Buesch <mb@bu3sch.de>
Cc: Michael Buesch <mb@bu3sch.de>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: "John W. Linville" <linville@tuxdriver.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Len Brown <lenb@kernel.org>
Cc: Greg KH <greg@kroah.com>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Make it possible to unregister a misc device object in a safe way during a
suspend/resume cycle.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Michael Buesch <mb@bu3sch.de>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: "John W. Linville" <linville@tuxdriver.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Len Brown <lenb@kernel.org>
Cc: Greg KH <greg@kroah.com>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Replace latency.c use with pm_qos_params use.
Signed-off-by: mark gross <mgross@linux.intel.com>
Cc: "John W. Linville" <linville@tuxdriver.com>
Cc: Len Brown <lenb@kernel.org>
Cc: Jaroslav Kysela <perex@suse.cz>
Cc: Takashi Iwai <tiwai@suse.de>
Cc: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The following patch is a generalization of the latency.c implementation done
by Arjan last year. It provides infrastructure for more than one parameter,
and exposes a user mode interface for processes to register pm_qos
expectations of processes.
This interface provides a kernel and user mode interface for registering
performance expectations by drivers, subsystems and user space applications on
one of the parameters.
Currently we have {cpu_dma_latency, network_latency, network_throughput} as
the initial set of pm_qos parameters.
The infrastructure exposes multiple misc device nodes one per implemented
parameter. The set of parameters implement is defined by pm_qos_power_init()
and pm_qos_params.h. This is done because having the available parameters
being runtime configurable or changeable from a driver was seen as too easy to
abuse.
For each parameter a list of performance requirements is maintained along with
an aggregated target value. The aggregated target value is updated with
changes to the requirement list or elements of the list. Typically the
aggregated target value is simply the max or min of the requirement values
held in the parameter list elements.
>From kernel mode the use of this interface is simple:
pm_qos_add_requirement(param_id, name, target_value):
Will insert a named element in the list for that identified PM_QOS
parameter with the target value. Upon change to this list the new target is
recomputed and any registered notifiers are called only if the target value
is now different.
pm_qos_update_requirement(param_id, name, new_target_value):
Will search the list identified by the param_id for the named list element
and then update its target value, calling the notification tree if the
aggregated target is changed. with that name is already registered.
pm_qos_remove_requirement(param_id, name):
Will search the identified list for the named element and remove it, after
removal it will update the aggregate target and call the notification tree
if the target was changed as a result of removing the named requirement.
>From user mode:
Only processes can register a pm_qos requirement. To provide for
automatic cleanup for process the interface requires the process to register
its parameter requirements in the following way:
To register the default pm_qos target for the specific parameter, the
process must open one of /dev/[cpu_dma_latency, network_latency,
network_throughput]
As long as the device node is held open that process has a registered
requirement on the parameter. The name of the requirement is
"process_<PID>" derived from the current->pid from within the open system
call.
To change the requested target value the process needs to write a s32
value to the open device node. This translates to a
pm_qos_update_requirement call.
To remove the user mode request for a target value simply close the device
node.
[akpm@linux-foundation.org: fix warnings]
[akpm@linux-foundation.org: fix build]
[akpm@linux-foundation.org: fix build again]
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: mark gross <mgross@linux.intel.com>
Cc: "John W. Linville" <linville@tuxdriver.com>
Cc: Len Brown <lenb@kernel.org>
Cc: Jaroslav Kysela <perex@suse.cz>
Cc: Takashi Iwai <tiwai@suse.de>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Venki Pallipadi <venkatesh.pallipadi@intel.com>
Cc: Adam Belay <abelay@novell.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
