user/sven/linux.git/include/linux/gfp.h, branch ipvs/experimental

BUILD_BUG_ON(): fix it and a couple of bogus uses of it

2009-09-23T14:39:29Z

gcc permitting variable length arrays makes the current construct used for BUILD_BUG_ON() useless, as that doesn't produce any diagnostic if the controlling expression isn't really constant. Instead, this patch makes it so that a bit field gets used here. Consequently, those uses where the condition isn't really constant now also need fixing. Note that in the gfp.h, kmemcheck.h, and virtio_config.h cases MAYBE_BUILD_BUG_ON() really just serves documentation purposes - even if the expression is compile time constant (__builtin_constant_p() yields true), the array is still deemed of variable length by gcc, and hence the whole expression doesn't have the intended effect. [akpm@linux-foundation.org: make arch/sparc/include/asm/vio.h compile] [akpm@linux-foundation.org: more nonsensical assertions in tpm.c..] Signed-off-by: Jan Beulich Cc: Andi Kleen Cc: Rusty Russell Cc: Catalin Marinas Cc: "David S. Miller" Cc: Rajiv Andrade Cc: Mimi Zohar Cc: James Morris Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

oom: move oom_killer_enable()/oom_killer_disable to where they belong

2009-09-22T14:17:38Z

Signed-off-by: Alexey Dobriyan Acked-by: David Rientjes Reviewed-by: KOSAKI Motohiro Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

page-allocator: remove dead function free_cold_page()

2009-09-22T14:17:34Z

The function free_cold_page() has no callers so delete it. Signed-off-by: Mel Gorman Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm: Extend gfp masking to the page allocator

2009-06-18T20:12:57Z

The page allocator also needs the masking of gfp flags during boot, so this moves it out of slab/slub and uses it with the page allocator as well. Signed-off-by: Benjamin Herrenschmidt Acked-by: Pekka Enberg Signed-off-by: Linus Torvalds

Merge branch 'akpm'

2009-06-17T02:50:13Z

* akpm: (182 commits) fbdev: bf54x-lq043fb: use kzalloc over kmalloc/memset fbdev: *bfin*: fix __dev{init,exit} markings fbdev: *bfin*: drop unnecessary calls to memset fbdev: bfin-t350mcqb-fb: drop unused local variables fbdev: blackfin has __raw I/O accessors, so use them in fb.h fbdev: s1d13xxxfb: add accelerated bitblt functions tcx: use standard fields for framebuffer physical address and length fbdev: add support for handoff from firmware to hw framebuffers intelfb: fix a bug when changing video timing fbdev: use framebuffer_release() for freeing fb_info structures radeon: P2G2CLK_ALWAYS_ONb tested twice, should 2nd be P2G2CLK_DAC_ALWAYS_ONb? s3c-fb: CPUFREQ frequency scaling support s3c-fb: fix resource releasing on error during probing carminefb: fix possible access beyond end of carmine_modedb[] acornfb: remove fb_mmap function mb862xxfb: use CONFIG_OF instead of CONFIG_PPC_OF mb862xxfb: restrict compliation of platform driver to PPC Samsung SoC Framebuffer driver: add Alpha Channel support atmel-lcdc: fix pixclock upper bound detection offb: use framebuffer_alloc() to allocate fb_info struct ... Manually fix up conflicts due to kmemcheck in mm/slab.c

page-allocator: use integer fields lookup for gfp_zone and check for errors in flags passed to the page allocator

2009-06-17T02:47:41Z

This simplifies the code in gfp_zone() and also keeps the ability of the compiler to use constant folding to get rid of gfp_zone processing. The lookup of the zone is done using a bitfield stored in an integer. So the code in gfp_zone is a simple extraction of bits from a constant bitfield. The compiler is generating a load of a constant into a register and then performs a shift and mask operation to get the zone from a gfp_t. No cachelines are touched and no branches have to be predicted by the compiler. We are doing some macro tricks here to convince the compiler to always do the constant folding if possible. Signed-off-by: Christoph Lameter Cc: KAMEZAWA Hiroyuki Reviewed-by: Mel Gorman Cc: Nick Piggin Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm, PM/Freezer: Disable OOM killer when tasks are frozen

2009-06-17T02:47:40Z

Currently, the following scenario appears to be possible in theory: * Tasks are frozen for hibernation or suspend. * Free pages are almost exhausted. * Certain piece of code in the suspend code path attempts to allocate some memory using GFP_KERNEL and allocation order less than or equal to PAGE_ALLOC_COSTLY_ORDER. * __alloc_pages_internal() cannot find a free page so it invokes the OOM killer. * The OOM killer attempts to kill a task, but the task is frozen, so it doesn't die immediately. * __alloc_pages_internal() jumps to 'restart', unsuccessfully tries to find a free page and invokes the OOM killer. * No progress can be made. Although it is now hard to trigger during hibernation due to the memory shrinking carried out by the hibernation code, it is theoretically possible to trigger during suspend after the memory shrinking has been removed from that code path. Moreover, since memory allocations are going to be used for the hibernation memory shrinking, it will be even more likely to happen during hibernation. To prevent it from happening, introduce the oom_killer_disabled switch that will cause __alloc_pages_internal() to fail in the situations in which the OOM killer would have been called and make the freezer set this switch after tasks have been successfully frozen. [akpm@linux-foundation.org: be nicer to the namespace] Signed-off-by: Rafael J. Wysocki Cc: Fengguang Wu Cc: David Rientjes Acked-by: Pavel Machek Cc: Mel Gorman Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

page allocator: do not check NUMA node ID when the caller knows the node is valid

2009-06-17T02:47:32Z

Callers of alloc_pages_node() can optionally specify -1 as a node to mean "allocate from the current node". However, a number of the callers in fast paths know for a fact their node is valid. To avoid a comparison and branch, this patch adds alloc_pages_exact_node() that only checks the nid with VM_BUG_ON(). Callers that know their node is valid are then converted. Signed-off-by: Mel Gorman Reviewed-by: Christoph Lameter Reviewed-by: KOSAKI Motohiro Reviewed-by: Pekka Enberg Acked-by: Paul Mundt [for the SLOB NUMA bits] Cc: Peter Zijlstra Cc: Nick Piggin Cc: Dave Hansen Cc: Lee Schermerhorn Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

page allocator: do not sanity check order in the fast path

2009-06-17T02:47:32Z

No user of the allocator API should be passing in an order >= MAX_ORDER but we check for it on each and every allocation. Delete this check and make it a VM_BUG_ON check further down the call path. [akpm@linux-foundation.org: s/VM_BUG_ON/WARN_ON_ONCE/] Signed-off-by: Mel Gorman Reviewed-by: Christoph Lameter Reviewed-by: KOSAKI Motohiro Reviewed-by: Pekka Enberg Cc: Peter Zijlstra Cc: Nick Piggin Cc: Dave Hansen Cc: Lee Schermerhorn Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

page allocator: replace __alloc_pages_internal() with __alloc_pages_nodemask()

2009-06-17T02:47:32Z

The start of a large patch series to clean up and optimise the page allocator. The performance improvements are in a wide range depending on the exact machine but the results I've seen so fair are approximately; kernbench: 0 to 0.12% (elapsed time) 0.49% to 3.20% (sys time) aim9: -4% to 30% (for page_test and brk_test) tbench: -1% to 4% hackbench: -2.5% to 3.45% (mostly within the noise though) netperf-udp -1.34% to 4.06% (varies between machines a bit) netperf-tcp -0.44% to 5.22% (varies between machines a bit) I haven't sysbench figures at hand, but previously they were within the -0.5% to 2% range. On netperf, the client and server were bound to opposite number CPUs to maximise the problems with cache line bouncing of the struct pages so I expect different people to report different results for netperf depending on their exact machine and how they ran the test (different machines, same cpus client/server, shared cache but two threads client/server, different socket client/server etc). I also measured the vmlinux sizes for a single x86-based config with CONFIG_DEBUG_INFO enabled but not CONFIG_DEBUG_VM. The core of the .config is based on the Debian Lenny kernel config so I expect it to be reasonably typical. This patch: __alloc_pages_internal is the core page allocator function but essentially it is an alias of __alloc_pages_nodemask. Naming a publicly available and exported function "internal" is also a big ugly. This patch renames __alloc_pages_internal() to __alloc_pages_nodemask() and deletes the old nodemask function. Warning - This patch renames an exported symbol. No kernel driver is affected by external drivers calling __alloc_pages_internal() should change the call to __alloc_pages_nodemask() without any alteration of parameters. Signed-off-by: Mel Gorman Reviewed-by: Christoph Lameter Reviewed-by: KOSAKI Motohiro Reviewed-by: Pekka Enberg Cc: Peter Zijlstra Cc: Nick Piggin Cc: Dave Hansen Cc: Lee Schermerhorn Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds