Avoid an atomic operation in kref_put() when the last reference is
dropped. On most platforms, atomic_read() is a plan read of the counter
and involves no atomic at all.
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
platform_get_irq*() now returns on -ENXIO when the resource cannot be
found. Ensure all users of platform_get_irq*() handle this error
appropriately.
Signed-off-by: David Vrabel <dvrabel@arcom.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
platform_get_irq*() cannot return 0 on error as 0 is a valid IRQ on some
platforms, return -ENXIO instead.
Signed-off-by: David Vrabel <dvrabel@arcom.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Moving uevent_seqnum and uevent_helper to kobject_uevent.c
because they are used even if CONFIG_SYSFS=n
while kernel/ksysfs.c is built only if CONFIG_SYSFS=y,
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
When calling sysfs_remove_dir() don't allow any further sysfs functions
to work for this kobject anymore. This fixes a nasty USB cdc-acm oops
on disconnect.
Many thanks to Bob Copeland and Paul Fulghum for taking the time to
track this down.
Cc: Bob Copeland <email@bobcopeland.com>
Cc: Paul Fulghum <paulkf@microgate.com>
Cc: Maneesh Soni <maneesh@in.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* master.kernel.org:/pub/scm/linux/kernel/git/davem/sparc-2.6: (230 commits)
[SPARC64]: Update defconfig.
[SPARC64]: Fix 2 bugs in huge page support.
[SPARC64]: CONFIG_BLK_DEV_RAM fix
[SPARC64]: Optimized TSB table initialization.
[SPARC64]: Allow CONFIG_MEMORY_HOTPLUG to build.
[SPARC64]: Use SLAB caches for TSB tables.
[SPARC64]: Don't kill the page allocator when growing a TSB.
[SPARC64]: Randomize mm->mmap_base when PF_RANDOMIZE is set.
[SPARC64]: Increase top of 32-bit process stack.
[SPARC64]: Top-down address space allocation for 32-bit tasks.
[SPARC64] bbc_i2c: Fix cpu check and add missing module license.
[SPARC64]: Fix and re-enable dynamic TSB sizing.
[SUNSU]: Fix missing spinlock initialization.
[TG3]: Do not try to access NIC_SRAM_DATA_SIG on Sun parts.
[SPARC64]: First cut at VIS simulator for Niagara.
[SPARC64]: Fix system type in /proc/cpuinfo and remove bogus OBP check.
[SPARC64]: Add SMT scheduling support for Niagara.
[SPARC64]: Fix 32-bit truncation which broke sparsemem.
[SPARC64]: Move over to sparsemem.
[SPARC64]: Fix new context version SMP handling.
...
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/shaggy/jfs-2.6:
JFS: add uid, gid, and umask mount options
JFS: Take logsync lock before testing mp->lsn
JFS: kzalloc conversion
JFS: Add missing file from fa3241d24c
JFS: Use the kthread_ API
JFS: Fix regression. fsck complains if symlinks do not have INLINEEA attribute
JFS: ext2 inode attributes for jfs
JFS: semaphore to mutex conversion.
JFS: make buddy table static
JFS: Add back directory i_size calculations for legacy partitions
* 'upstream-linus' of master.kernel.org:/pub/scm/linux/kernel/git/jgarzik/netdev-2.6: (150 commits)
[PATCH] ipw2100: Update version ipw2100 stamp to 1.2.2
[PATCH] ipw2100: move mutex.h include from ipw2100.c to ipw2100.h
[PATCH] ipw2100: semaphore to mutexes conversion
[PATCH] ipw2100: Fix radiotap code gcc warning
[PATCH] ipw2100: add radiotap headers to packtes captured in monitor mode
[PATCH] ipw2x00: expend Copyright to 2006
[PATCH] drivers/net/wireless/ipw2200.c: fix an array overun
[PATCH] ieee80211: Don't update network statistics from off-channel packets.
[PATCH] ipw2200: Update ipw2200 version stamp to 1.1.1
[PATCH] ipw2200: switch to the new ipw2200-fw-3.0 image format
[PATCH] ipw2200: wireless extension sensitivity threshold support
[PATCH] ipw2200: Enables the "slow diversity" algorithm
[PATCH] ipw2200: Set a meaningful silence threshold value
[PATCH] ipw2200: export `debug' module param only if CONFIG_IPW2200_DEBUG
[PATCH] ipw2200: Change debug level for firmware error logging
[PATCH] ipw2200: Filter unsupported channels out in ad-hoc mode
[PATCH] ipw2200: Fix ipw_sw_reset() implementation inconsistent with comment
[PATCH] ipw2200: Fix rf_kill is activated after mode change with 'disable=1'
[PATCH] ipw2200: remove the WPA card associates to non-WPA AP checking
[PATCH] ipw2200: Add signal level to iwlist scan output
...
* 'block-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/block:
[PATCH] fix rmmod problems with elevator attributes, clean them up
[PATCH] elevator_t lifetime rules and sysfs fixes
[PATCH] noise removal: cfq-iosched.c
[PATCH] don't bother with refcounting for cfq_data
[PATCH] fix sysfs interaction and lifetime rules handling for queues
[PATCH] regularize blk_cleanup_queue() use
[PATCH] fix cfq_get_queue()/ioprio_set(2) races
[PATCH] deal with rmmod/put_io_context() races
[PATCH] stop elv_unregister() from rogering other iosched's data, fix locking
[PATCH] stop cfq from pinning queue down
[PATCH] make cfq_exit_queue() prune the cfq_io_context for that queue
[PATCH] fix the exclusion for ioprio_set()
[PATCH] keep sync and async cfq_queue separate
[PATCH] switch to use of ->key to get cfq_data by cfq_io_context
[PATCH] stop leaking cfq_data in cfq_set_request()
[PATCH] fix cfq hash lookups
[PATCH] fix locking in queue_requests_store()
[PATCH] fix double-free in blk_init_queue_node()
[PATCH] don't do exit_io_context() until we know we won't be doing any IO
1) huge_pte_offset() did not check the page table hierarchy
elements as being empty correctly, resulting in an OOPS
2) Need platform specific hugetlb_get_unmapped_area() to handle
the top-down vs. bottom-up address space allocation strategies.
Signed-off-by: David S. Miller <davem@davemloft.net>
init/do_mounts_rd.c depends upon CONFIG_BLK_DEV_RAM, not CONFIG_BLK_DEV_INITRD.
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
We only need to write an invalid tag every 16 bytes,
so taking advantage of this can save many instructions
compared to the simple memset() call we make now.
A prefetching implementation is implemented for sun4u
and a block-init store version if implemented for Niagara.
The next trick is to be able to perform an init and
a copy_tsb() in parallel when growing a TSB table.
Signed-off-by: David S. Miller <davem@davemloft.net>
online_page() is straightforward, and then add a dummy
remove_memory() that returns -EINVAL just like i386.
There is no point in implementing remove_memory() since
__remove_pages() has no implementation either.
Signed-off-by: David S. Miller <davem@davemloft.net>
Try only lightly on > 1 order allocations.
If a grow fails, we are under memory pressure, so do not try
to grow the TSB for this address space any more.
If a > 0 order TSB allocation fails on a new fork, retry using
a 0 order allocation.
Signed-off-by: David S. Miller <davem@davemloft.net>
Put it one page below the top of the 32-bit address space.
This gives us ~16MB more address space to work with.
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently allocations are very constrained for 32-bit processes.
It grows down-up from 0x70000000 to 0xf0000000 which gives about
2GB of stack + dynamic mmap() space.
So support the top-down method, and we need to override the
generic helper function in order to deal with D-cache coloring.
With these changes I was able to squeeze out a mmap() just over
3.6GB in size in a 32-bit process.
Signed-off-by: David S. Miller <davem@davemloft.net>
This is good for up to %50 performance improvement of some test cases.
The problem has been the race conditions, and hopefully I've plugged
them all up here.
1) There was a serious race in switch_mm() wrt. lazy TLB
switching to and from kernel threads.
We could erroneously skip a tsb_context_switch() and thus
use a stale TSB across a TSB grow event.
There is a big comment now in that function describing
exactly how it can happen.
2) All code paths that do something with the TSB need to be
guarded with the mm->context.lock spinlock. This makes
page table flushing paths properly synchronize with both
TSB growing and TLB context changes.
3) TSB growing events are moved to the end of successful fault
processing. Previously it was in update_mmu_cache() but
that is deadlock prone. At the end of do_sparc64_fault()
we hold no spinlocks that could deadlock the TSB grow
sequence. We also have dropped the address space semaphore.
While we're here, add prefetching to the copy_tsb() routine
and put it in assembler into the tsb.S file. This piece of
code is quite time critical.
There are some small negative side effects to this code which
can be improved upon. In particular we grab the mm->context.lock
even for the tsb insert done by update_mmu_cache() now and that's
a bit excessive. We can get rid of that locking, and the same
lock taking in flush_tsb_user(), by disabling PSTATE_IE around
the whole operation including the capturing of the tsb pointer
and tsb_nentries value. That would work because anyone growing
the TSB won't free up the old TSB until all cpus respond to the
TSB change cross call.
I'm not quite so confident in that optimization to put it in
right now, but eventually we might be able to and the description
is here for reference.
This code seems very solid now. It passes several parallel GCC
bootstrap builds, and our favorite "nut cruncher" stress test which is
a full "make -j8192" build of a "make allmodconfig" kernel. That puts
about 256 processes on each cpu's run queue, makes lots of process cpu
migrations occur, causes lots of page table and TLB flushing activity,
incurs many context version number changes, and it swaps the machine
real far out to disk even though there is 16GB of ram on this test
system. :-)
Signed-off-by: David S. Miller <davem@davemloft.net>
Eric Dumazet
David Vrabel
Greg Kroah-Hartman
Jun'ichi Nomura
Linus Torvalds
Jeff Garzik
David S. Miller
David S. Miller
Andrew Morton