Hello, I fixed and tested a small bug in lib/sort.c file, heap sort
function.
The fix avoids unnecessary swap of contents when i is 0 (saves few loads
and stores), which happens every time sort function is called. I felt the
fix is worth bringing it to your attention given the importance and
frequent use of the sort function.
Acked-by: Matt Mackall <mpm@selenic.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
It would be nice if the argv_split library function could gracefully handle
a NULL pointer in the argcp parameter, so as to allow functions using it
that did not care about the value of argc to not have to declare a useless
variable. This patch accomplishes that. Tested by me, with successful
results.
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Satyam Sharma <satyam@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Slab constructors currently have a flags parameter that is never used. And
the order of the arguments is opposite to other slab functions. The object
pointer is placed before the kmem_cache pointer.
Convert
ctor(void *object, struct kmem_cache *s, unsigned long flags)
to
ctor(struct kmem_cache *s, void *object)
throughout the kernel
[akpm@linux-foundation.org: coupla fixes]
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Given a set of objects, floating proportions aims to efficiently give the
proportional 'activity' of a single item as compared to the whole set. Where
'activity' is a measure of a temporal property of the items.
It is efficient in that it need not inspect any other items of the set
in order to provide the answer. It is not even needed to know how many
other items there are.
It has one parameter, and that is the period of 'time' over which the
'activity' is measured.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch marks a number of allocations that are either short-lived such as
network buffers or are reclaimable such as inode allocations. When something
like updatedb is called, long-lived and unmovable kernel allocations tend to
be spread throughout the address space which increases fragmentation.
This patch groups these allocations together as much as possible by adding a
new MIGRATE_TYPE. The MIGRATE_RECLAIMABLE type is for allocations that can be
reclaimed on demand, but not moved. i.e. they can be migrated by deleting
them and re-reading the information from elsewhere.
Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Cc: Andy Whitcroft <apw@shadowen.org>
Cc: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
A while back, Nick Piggin introduced a patch to reduce the node memory
usage for small files (commit cfd9b7df4a):
-#define RADIX_TREE_MAP_SHIFT 6
+#define RADIX_TREE_MAP_SHIFT (CONFIG_BASE_SMALL ? 4 : 6)
Unfortunately, he didn't take into account the fact that the
calculation of the maximum path was based on an assumption of having
to round up:
#define RADIX_TREE_MAX_PATH (RADIX_TREE_INDEX_BITS/RADIX_TREE_MAP_SHIFT + 2)
So, if CONFIG_BASE_SMALL is set, you will end up with a
RADIX_TREE_MAX_PATH that is one greater than necessary. The practical
upshot of this is just a bit of wasted memory (one long in the
height_to_maxindex array, an extra pre-allocated radix tree node per
cpu, and extra stack usage in a couple of functions), but it seems
worth getting right.
It's also worth noting that I never build with CONFIG_BASE_SMALL.
What I did to test this was duplicate the code in a small user-space
program and check the results of the calculations for max path and the
contents of the height_to_maxindex array.
Signed-off-by: Jeff Moyer <jmoyer@redhat.com>
Acked-by: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Rather than sign direct radix-tree pointers with a special bit, sign the
indirect one that hangs off the root. This means that, given a lookup_slot
operation, the invalid result will be differentiated from the valid
(previously, valid results could have the bit either set or clear).
This does not affect slot lookups which occur under lock -- they can never
return an invalid result. Is needed in future for lockless pagecache.
Signed-off-by: Nick Piggin <npiggin@suse.de>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Introduce radix_tree_next_hole(root, index, max_scan) to scan radix tree for
the first hole. It will be used in interleaved readahead.
The implementation is dumb and obviously correct. It can help debug(and
document) the possible smart one in future.
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Fengguang Wu <wfg@mail.ustc.edu.cn>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Optionally add a boot delay after each kernel printk() call, crudely
measured in milliseconds, with a maximum delay of 10 seconds per printk.
Enable CONFIG_BOOT_PRINTK_DELAY=y and then add (e.g.):
"lpj=loops_per_jiffy boot_delay=100"
to the kernel command line.
It has been useful in cases like "during boot, my machine just reboots or the
screen goes black" by slowing down printk, (and adding initcall_debug), we can
usually see the last thing that happened before the lights went out which is
usually a valuable clue.
[akpm@linux-foundation.org: not all architectures implement CONFIG_HZ]
[akpm@linux-foundation.org: fix lots of stuff]
[bunk@stusta.de: kernel/printk.c: make 2 variables static]
[heiko.carstens@de.ibm.com: fix slow down printk on boot compile error]
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Dave Jones <davej@redhat.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* master.kernel.org:/pub/scm/linux/kernel/git/gregkh/pci-2.6: (37 commits)
PCI: merge almost all of pci_32.h and pci_64.h together
PCI: X86: Introduce and enable PCI domain support
PCI: Add 'nodomains' boot option, and pci_domains_supported global
PCI: modify PCI bridge control ISA flag for clarity
PCI: use _CRS for PCI resource allocation
PCI: avoid P2P prefetch window for expansion ROMs
PCI: skip ISA ioresource alignment on some systems
PCI: remove transparent bridge sizing
pci: write file size to inode on proc bus file write
pci: use size stored in proc_dir_entry for proc bus files
pci: implement "pci=noaer"
PCI: fix IDE legacy mode resources
MSI: Use correct data offset for 32-bit MSI in read_msi_msg()
PCI: Fix incorrect argument order to list_add_tail() in PCI dynamic ID code
PCI: i386: Compaq EVO N800c needs PCI bus renumbering
PCI: Remove no longer correct documentation regarding MSI vector assignment
PCI: re-enable onboard sound on "MSI K8T Neo2-FIR"
PCI: quirk_vt82c586_acpi: Omit reading PCI revision ID
PCI: quirk amd_8131_mmrbc: Omit reading pci revision ID
cpqphp: Use PCI_CLASS_REVISION instead of PCI_REVISION_ID for read
...
On at least ARM (and I'm told MIPS too) dma_free_coherent() has a newish
call context requirement: unlike its dma_alloc_coherent() sibling, it may
not be called with IRQs disabled. (This was new behavior on ARM as of late
2005, caused by ARM SMP updates.) This little surprise can be annoyingly
driver-visible.
Since it looks like that restriction won't be removed, this patch changes
the definition of the API to include that requirement. Also, to help catch
nonportable drivers, it updates the x86 and swiotlb versions to include the
relevant warnings. (I already observed that it trips on the
bus_reset_tasklet of the new firewire_ohci driver.)
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: David Miller <davem@davemloft.net>
Acked-by: Russell King <rmk@arm.linux.org.uk>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Subbaiah Venkata
Adrian Bunk
Neil Horman
Christoph Lameter
Peter Zijlstra
Linus Torvalds
Mel Gorman
Jeff Moyer
Nick Piggin
Fengguang Wu
Randy Dunlap
Jens Axboe
Al Viro
David Brownell
Greg Kroah-Hartman