* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (162 commits)
tracing/kprobes: unregister_trace_probe needs to be called under mutex
perf: expose event__process function
perf events: Fix mmap offset determination
perf, powerpc: fsl_emb: Restore setting perf_sample_data.period
perf, powerpc: Convert the FSL driver to use local64_t
perf tools: Don't keep unreferenced maps when unmaps are detected
perf session: Invalidate last_match when removing threads from rb_tree
perf session: Free the ref_reloc_sym memory at the right place
x86,mmiotrace: Add support for tracing STOS instruction
perf, sched migration: Librarize task states and event headers helpers
perf, sched migration: Librarize the GUI class
perf, sched migration: Make the GUI class client agnostic
perf, sched migration: Make it vertically scrollable
perf, sched migration: Parameterize cpu height and spacing
perf, sched migration: Fix key bindings
perf, sched migration: Ignore unhandled task states
perf, sched migration: Handle ignored migrate out events
perf: New migration tool overview
tracing: Drop cpparg() macro
perf: Use tracepoint_synchronize_unregister() to flush any pending tracepoint call
...
Fix up trivial conflicts in Makefile and drivers/cpufreq/cpufreq.c
It is now possible to assign options to AS, CC and LD
on the command line - which is only used when building modules.
{A,C,LD}FLAGS_MODULE was all used both in the top-level Makefile
in the arch makefiles, thus users had no way to specify
additional options to AS, CC, LD when building modules
without overriding the original value.
Introduce a new set of variables KBUILD_{A,C,LD}FLAGS_MODULE
that is used by arch specific files and free up
{A,C,LD}FLAGS_MODULE so they can be assigned on
the command line.
All arch Makefiles that used the old variables has been updated.
Note: Previously we had a MODFLAGS variable for both
AS and CC. But in favour of consistency this was dropped.
So in some cases arch Makefile has one assignmnet replaced by
two assignmnets.
Note2: MODFLAGS was not documented and is dropped
without any notice. I do not expect much/any breakage
from this.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Denys Vlasenko <vda.linux@googlemail.com>
Cc: Haavard Skinnemoen <hskinnemoen@atmel.com>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Chen Liqin <liqin.chen@sunplusct.com>
Acked-by: Mike Frysinger <vapier@gentoo.org> [blackfin]
Acked-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com> [avr32]
Signed-off-by: Michal Marek <mmarek@suse.cz>
On 64bit, local_t is of size long, and thus we make local64_t an alias.
On 32bit, we fall back to atomic64_t. (architecture can provide optimized
32-bit version)
(This new facility is to be used by perf events optimizations.)
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: linux-arch@vger.kernel.org
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (44 commits)
vlynq: make whole Kconfig-menu dependant on architecture
add descriptive comment for TIF_MEMDIE task flag declaration.
EEPROM: max6875: Header file cleanup
EEPROM: 93cx6: Header file cleanup
EEPROM: Header file cleanup
agp: use NULL instead of 0 when pointer is needed
rtc-v3020: make bitfield unsigned
PCI: make bitfield unsigned
jbd2: use NULL instead of 0 when pointer is needed
cciss: fix shadows sparse warning
doc: inode uses a mutex instead of a semaphore.
uml: i386: Avoid redefinition of NR_syscalls
fix "seperate" typos in comments
cocbalt_lcdfb: correct sections
doc: Change urls for sparse
Powerpc: wii: Fix typo in comment
i2o: cleanup some exit paths
Documentation/: it's -> its where appropriate
UML: Fix compiler warning due to missing task_struct declaration
UML: add kernel.h include to signal.c
...
* 'timers-for-linus-cleanups' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
avr32: Fix typo in read_persistent_clock()
sparc: Convert sparc to use read/update_persistent_clock
cris: Convert cris to use read/update_persistent_clock
m68k: Convert m68k to use read/update_persistent_clock
m32r: Convert m32r to use read/update_peristent_clock
blackfin: Convert blackfin to use read/update_persistent_clock
ia64: Convert ia64 to use read/update_persistent_clock
avr32: Convert avr32 to use read/update_persistent_clock
h8300: Convert h8300 to use read/update_persistent_clock
frv: Convert frv to use read/update_persistent_clock
mn10300: Convert mn10300 to use read/update_persistent_clock
alpha: Convert alpha to use read/update_persistent_clock
xtensa: Fix unnecessary setting of xtime
time: Clean up direct xtime usage in xen
In preparation for removing volatile from the atomic_t definition, this
patch adds a volatile cast to all the atomic read functions.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch fixes a build failure introduced by 1d8393171 ("avr32: use
generic ptrace_resume code") which had the static keyword as a leftover.
arch/avr32/kernel/ptrace.c:32: error: static declaration of `user_enable_single_step' follows non-static declaration
include/linux/ptrace.h:268: error: previous declaration of `user_enable_single_step' was here
References:
[1]http://kisskb.ellerman.id.au/kisskb/buildresult/2448162/
Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
Cc: Haavard Skinnemoen <hskinnemoen@atmel.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix fallout from the persistent_clock changes.
Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
Cc: John Stultz <johnstul@us.ibm.com>
Cc: Haavard Skinnemoen <hskinnemoen@atmel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.
percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.
http://userweb.kernel.org/~tj/misc/slabh-sweep.py
The script does the followings.
* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.
* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.
* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.
The conversion was done in the following steps.
1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.
2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.
3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.
4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.
5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.
6. percpu.h was updated not to include slab.h.
7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).
* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig
8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.
Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
This patch converts the avr32 architecture to use the generic
read_persistent_clock and update_persistent_clock interfaces, reducing
the amount of arch specific code we have to maintain, and allowing for
further cleanups in the future.
I have not built or tested this patch, so help from arch maintainers
would be appreciated.
Signed-off-by: John Stultz <johnstul@us.ibm.com>
Cc: Haavard Skinnemoen <hskinnemoen@atmel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
LKML-Reference: <1267675049-12337-7-git-send-email-johnstul@us.ibm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Use the generic ptrace_resume code for PTRACE_SYSCALL, PTRACE_CONT,
PTRACE_KILL and PTRACE_SINGLESTEP. This implies defining
arch_has_single_step in <asm/ptrace.h> and implementing the
user_enable_single_step and user_disable_single_step functions, which also
causes the breakpoint information to be cleared on fork, which could be
considered a bug fix.
Also the TIF_SYSCALL_TRACE thread flag is now cleared on PTRACE_KILL which
it previously wasn't which is consistent with all architectures using the
modern ptrace code.
Currently avr32 doesn't implement any code to disable single stepping when
one of the non-syscall requests is called which seems wrong, but I've left
it as-is for now.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Roland McGrath <roland@redhat.com>
Acked-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Adding vbus_pin_inverted so that the usb detect pin can be active high
or low depending on HW implementation also replaced the
gpio_get_value(udc->vbus_pin); with a call to vbus_is_present(udc); This
allows the driver to be loaded and save about 0,15W on the consumption.
Signed-off-by: Eirik Aanonsen <eaa@wprmedical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
On VIVT ARM, when we have multiple shared mappings of the same file
in the same MM, we need to ensure that we have coherency across all
copies. We do this via make_coherent() by making the pages
uncacheable.
This used to work fine, until we allowed highmem with highpte - we
now have a page table which is mapped as required, and is not available
for modification via update_mmu_cache().
Ralf Beache suggested getting rid of the PTE value passed to
update_mmu_cache():
On MIPS update_mmu_cache() calls __update_tlb() which walks pagetables
to construct a pointer to the pte again. Passing a pte_t * is much
more elegant. Maybe we might even replace the pte argument with the
pte_t?
Ben Herrenschmidt would also like the pte pointer for PowerPC:
Passing the ptep in there is exactly what I want. I want that
-instead- of the PTE value, because I have issue on some ppc cases,
for I$/D$ coherency, where set_pte_at() may decide to mask out the
_PAGE_EXEC.
So, pass in the mapped page table pointer into update_mmu_cache(), and
remove the PTE value, updating all implementations and call sites to
suit.
Includes a fix from Stephen Rothwell:
sparc: fix fallout from update_mmu_cache API change
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This patch will check if the kzalloc for the MCI DMA struct actually
returns a valid address, and also clean up properly if it fails or the
function fails at a later stage.
This also silences a compiler warning about using the slave variable
uninitialized.
Signed-off-by: Hans-Christian Egtvedt <hans-christian.egtvedt@atmel.com>
Signed-off-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
* 'for-33' of git://repo.or.cz/linux-kbuild: (29 commits)
net: fix for utsrelease.h moving to generated
gen_init_cpio: fixed fwrite warning
kbuild: fix make clean after mismerge
kbuild: generate modules.builtin
genksyms: properly consider EXPORT_UNUSED_SYMBOL{,_GPL}()
score: add asm/asm-offsets.h wrapper
unifdef: update to upstream revision 1.190
kbuild: specify absolute paths for cscope
kbuild: create include/generated in silentoldconfig
scripts/package: deb-pkg: use fakeroot if available
scripts/package: add KBUILD_PKG_ROOTCMD variable
scripts/package: tar-pkg: use tar --owner=root
Kbuild: clean up marker
net: add net_tstamp.h to headers_install
kbuild: move utsrelease.h to include/generated
kbuild: move autoconf.h to include/generated
drop explicit include of autoconf.h
kbuild: move compile.h to include/generated
kbuild: drop include/asm
kbuild: do not check for include/asm-$ARCH
...
Fixed non-conflicting clean merge of modpost.c as per comments from
Stephen Rothwell (modpost.c had grown an include of linux/autoconf.h
that needed to be changed to generated/autoconf.h)
Currently all architectures but microblaze unconditionally define
USE_ELF_CORE_DUMP. The microblaze omission seems like an error to me, so
let's kill this ifdef and make sure we are the same everywhere.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Hugh Dickins <hugh.dickins@tiscali.co.uk>
Cc: <linux-arch@vger.kernel.org>
Cc: Michal Simek <michal.simek@petalogix.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'core-locking-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (26 commits)
clockevents: Convert to raw_spinlock
clockevents: Make tick_device_lock static
debugobjects: Convert to raw_spinlocks
perf_event: Convert to raw_spinlock
hrtimers: Convert to raw_spinlocks
genirq: Convert irq_desc.lock to raw_spinlock
smp: Convert smplocks to raw_spinlocks
rtmutes: Convert rtmutex.lock to raw_spinlock
sched: Convert pi_lock to raw_spinlock
sched: Convert cpupri lock to raw_spinlock
sched: Convert rt_runtime_lock to raw_spinlock
sched: Convert rq->lock to raw_spinlock
plist: Make plist debugging raw_spinlock aware
bkl: Fixup core_lock fallout
locking: Cleanup the name space completely
locking: Further name space cleanups
alpha: Fix fallout from locking changes
locking: Implement new raw_spinlock
locking: Convert raw_rwlock functions to arch_rwlock
locking: Convert raw_rwlock to arch_rwlock
...
* git://git.kernel.org/pub/scm/linux/kernel/git/hskinnemoen/avr32-2.6:
avr32: update default configurations for ATNGW100, ATSTK1002 and ATSTK1006
avr32: add default configurations for ATNGW100 mkII and EVKLCD10X
avr32: add support for ATNGW100 mkII board
avr32: convert to asm-generic/hardirq.h
avr32: add two new at91 to cpu.h definition
avr32: clean up linker script using standard macros.
avr32: MRMT: correct setup of SPI slaves
avr32: function for independently setting up SPI slaves
avr32: re-instate MCI WP/CD pin assignments for ATNGW100
Allow the use of another DMA controller driver in atmel-mci sd/mmc driver.
This adds a generic dma_slave pointer to the mci platform structure where
we can store DMA controller information. In atmel-mci we use information
provided by this structure to initialize the driver (with new helper
functions that are architecture dependant).
This also adds at32/avr32 chip modifications to cope with this new access
method.
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Cc: Haavard Skinnemoen <hskinnemoen@atmel.com>
Cc: <linux-mmc@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Convert locks which cannot be sleeping locks in preempt-rt to
raw_spinlocks.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Ingo Molnar <mingo@elte.hu>
This patch updates the default configuration for ATNGW100 (also for the
EVKLCD10X configs), ATSTK1002 and ATSTK1006.
By default all kernels will now have support for EXT2/3/4 out of the box, this
is handy if the user wants to boot from SD-Card.
Signed-off-by: Hans-Christian Egtvedt <hans-christian.egtvedt@atmel.com>
Signed-off-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
This patch adds three default configurations for ATNGW100 mkII and ATNGW100
mkII with either EVKLCD100 or EVKLCD101 addon board.
Signed-off-by: Hans-Christian Egtvedt <hans-christian.egtvedt@atmel.com>
Signed-off-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
This patch adds board support for ATNGW100 mkII. This board is an upgrade of
the ATNGW100 where the difference is an additional 256 MB NAND flash device and
128 MB 32-bit SDRAM instead of the 32 MB 16-bit SDRAM on ATNGW100.
Tested on ATNGW100 mkII, duh (-:
Signed-off-by: Hans-Christian Egtvedt <hans-christian.egtvedt@atmel.com>
Signed-off-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
The simplest method was to add an extra asm-offsets.h
file in arch/$ARCH/include/asm that references the generated file.
We can now migrate the architectures one-by-one to reference
the generated file direct - and when done we can delete the
temporary arch/$ARCH/include/asm/asm-offsets.h file.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Michal Marek <mmarek@suse.cz>
New helper - sys_mmap_pgoff(); switch syscalls to using it.
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* 'for-2.6.33' of git://git.kernel.dk/linux-2.6-block: (113 commits)
cfq-iosched: Do not access cfqq after freeing it
block: include linux/err.h to use ERR_PTR
cfq-iosched: use call_rcu() instead of doing grace period stall on queue exit
blkio: Allow CFQ group IO scheduling even when CFQ is a module
blkio: Implement dynamic io controlling policy registration
blkio: Export some symbols from blkio as its user CFQ can be a module
block: Fix io_context leak after failure of clone with CLONE_IO
block: Fix io_context leak after clone with CLONE_IO
cfq-iosched: make nonrot check logic consistent
io controller: quick fix for blk-cgroup and modular CFQ
cfq-iosched: move IO controller declerations to a header file
cfq-iosched: fix compile problem with !CONFIG_CGROUP
blkio: Documentation
blkio: Wait on sync-noidle queue even if rq_noidle = 1
blkio: Implement group_isolation tunable
blkio: Determine async workload length based on total number of queues
blkio: Wait for cfq queue to get backlogged if group is empty
blkio: Propagate cgroup weight updation to cfq groups
blkio: Drop the reference to queue once the task changes cgroup
blkio: Provide some isolation between groups
...
Use the new unreachable() macro instead of for(;;);
Signed-off-by: David Daney <ddaney@caviumnetworks.com>
Acked-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Mtdblock driver doesn't call flush_dcache_page for pages in request. So,
this causes problems on architectures where the icache doesn't fill from
the dcache or with dcache aliases. The patch fixes this.
The ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE symbol was introduced to avoid
pointless empty cache-thrashing loops on architectures for which
flush_dcache_page() is a no-op. Every architecture was provided with this
flush pages on architectires where ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE is
equal 1 or do nothing otherwise.
See "fix mtd_blkdevs problem with caches on some architectures" discussion
on LKML for more information.
Signed-off-by: Ilya Loginov <isloginov@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Peter Horton <phorton@bitbox.co.uk>
Cc: "Ed L. Cashin" <ecashin@coraid.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Many Atmel SOC are embedding a LCD controller. This patch removes the long
dependency line for this Atmel LCD framebuffer driver configuration entry.
The HAVE_FB_ATMEL configuration option is located in the video Kconfig file
as it may be setup by ARM/AT91 and AVR32 chips.
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Acked-by: Andrew Victor <linux@maxim.org.za>
cpu_is_xxx() macros are identifying generic at91sam9g45 chip. This patch adds
the capacity to differentiate Engineering Samples and final lots through the
inclusion of at91_cpu_fully_identify() and the related chip IDs with chip
version field preserved.
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Acked-by: Hans-Christian Egtvedt <hans-christian.egtvedt@atmel.com>
Somme common drivers will need those at91 cpu_is_xxx() definitions. As
at91sam9g10 and at91sam9g45 are on the way to linus' tree, here is the patch
that adds those chips to cpu.h in AVR32 architecture.
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
Meaning receive multiple messages, reducing the number of syscalls and
net stack entry/exit operations.
Next patches will introduce mechanisms where protocols that want to
optimize this operation will provide an unlocked_recvmsg operation.
This takes into account comments made by:
. Paul Moore: sock_recvmsg is called only for the first datagram,
sock_recvmsg_nosec is used for the rest.
. Caitlin Bestler: recvmmsg now has a struct timespec timeout, that
works in the same fashion as the ppoll one.
If the underlying protocol returns a datagram with MSG_OOB set, this
will make recvmmsg return right away with as many datagrams (+ the OOB
one) it has received so far.
. Rémi Denis-Courmont & Steven Whitehouse: If we receive N < vlen
datagrams and then recvmsg returns an error, recvmmsg will return
the successfully received datagrams, store the error and return it
in the next call.
This paves the way for a subsequent optimization, sk_prot->unlocked_recvmsg,
where we will be able to acquire the lock only at batch start and end, not at
every underlying recvmsg call.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Create a new socket level option to report number of queue overflows
Recently I augmented the AF_PACKET protocol to report the number of frames lost
on the socket receive queue between any two enqueued frames. This value was
exported via a SOL_PACKET level cmsg. AFter I completed that work it was
requested that this feature be generalized so that any datagram oriented socket
could make use of this option. As such I've created this patch, It creates a
new SOL_SOCKET level option called SO_RXQ_OVFL, which when enabled exports a
SOL_SOCKET level cmsg that reports the nubmer of times the sk_receive_queue
overflowed between any two given frames. It also augments the AF_PACKET
protocol to take advantage of this new feature (as it previously did not touch
sk->sk_drops, which this patch uses to record the overflow count). Tested
successfully by me.
Notes:
1) Unlike my previous patch, this patch simply records the sk_drops value, which
is not a number of drops between packets, but rather a total number of drops.
Deltas must be computed in user space.
2) While this patch currently works with datagram oriented protocols, it will
also be accepted by non-datagram oriented protocols. I'm not sure if thats
agreeable to everyone, but my argument in favor of doing so is that, for those
protocols which aren't applicable to this option, sk_drops will always be zero,
and reporting no drops on a receive queue that isn't used for those
non-participating protocols seems reasonable to me. This also saves us having
to code in a per-protocol opt in mechanism.
3) This applies cleanly to net-next assuming that commit
977750076d (my af packet cmsg patch) is reverted
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Linus Torvalds