- 08 12月, 2006 40 次提交
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由 Christoph Lameter 提交于
SLAB_KERNEL is an alias of GFP_KERNEL. Signed-off-by: NChristoph Lameter <clameter@sgi.com> Signed-off-by: NAndrew Morton <akpm@osdl.org> Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
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由 Christoph Lameter 提交于
SLAB_ATOMIC is an alias of GFP_ATOMIC Signed-off-by: NChristoph Lameter <clameter@sgi.com> Signed-off-by: NAndrew Morton <akpm@osdl.org> Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
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由 Christoph Lameter 提交于
SLAB_USER is an alias of GFP_USER Signed-off-by: NChristoph Lameter <clameter@sgi.com> Signed-off-by: NAndrew Morton <akpm@osdl.org> Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
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由 Christoph Lameter 提交于
SLAB_NOFS is an alias of GFP_NOFS. Signed-off-by: NChristoph Lameter <clameter@sgi.com> Signed-off-by: NAndrew Morton <akpm@osdl.org> Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
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由 Christoph Lameter 提交于
SLAB_NOIO is an alias of GFP_NOIO with a single instance of use. Signed-off-by: NChristoph Lameter <clameter@sgi.com> Signed-off-by: NAndrew Morton <akpm@osdl.org> Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
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由 Christoph Lameter 提交于
SLAB_LEVEL_MASK is only used internally to the slab and is and alias of GFP_LEVEL_MASK. Signed-off-by: NChristoph Lameter <clameter@sgi.com> Signed-off-by: NAndrew Morton <akpm@osdl.org> Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
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由 Christoph Lameter 提交于
It is only used internally in the slab. Signed-off-by: NChristoph Lameter <clameter@sgi.com> Signed-off-by: NAndrew Morton <akpm@osdl.org> Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
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由 Hugh Dickins 提交于
David Binderman and his Intel C compiler rightly observe that install_file_pte no longer has any use for its pte_val. Signed-off-by: NHugh Dickins <hugh@veritas.com> Cc: d binderman <dcb314@hotmail.com> Signed-off-by: NAndrew Morton <akpm@osdl.org> Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
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由 Andy Whitcroft 提交于
These patches introduced new switch statements which are indented contrary to the concensus in mm/*.c. Fix them up to match that concensus. [PATCH] node local per-cpu-pages [PATCH] ZVC: Scale thresholds depending on the size of the system commit e7c8d5c9 commit df9ecabaSigned-off-by: NAndy Whitcroft <apw@shadowen.org> Cc: Christoph Lameter <clameter@engr.sgi.com> Signed-off-by: NAndrew Morton <akpm@osdl.org> Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
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由 Eric Sandeen 提交于
The fsfuzzer found this; with a corrupt small swapfile that claims to have many pages: [root]# file swap.741.img swap.741.img: Linux/i386 swap file (new style) 1 (4K pages) size 1040191487 pages [root]# ls -l swap.741.img -rw-r--r-- 1 root root 16777216 Nov 22 05:18 swap.741.img sys_swapon() will try to vmalloc all those pages, and -then- check to see if the file is actually that large: if (!(p->swap_map = vmalloc(maxpages * sizeof(short)))) { <snip> if (swapfilesize && maxpages > swapfilesize) { printk(KERN_WARNING "Swap area shorter than signature indicates\n"); It seems to me that it would make more sense to move this test up before the vmalloc, with the other checks, to avoid the OOM-killer in this situation... Signed-off-by: NEric Sandeen <sandeen@redhat.com> Cc: Hugh Dickins <hugh@veritas.com> Signed-off-by: NAndrew Morton <akpm@osdl.org> Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
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由 Andy Whitcroft 提交于
x86 NUMA systems only define bootmem for node 0. alloc_bootmem_node() and friends therefore ignore the passed pgdat and use NODE_DATA(0) in all cases. This leads to the following warnings as we are not using the passed parameter: .../mm/page_alloc.c: In function 'zone_wait_table_init': .../mm/page_alloc.c:2259: warning: unused variable 'pgdat' One option would be to define all variables used with these macros __attribute__ ((unused)), but this would leave us exposed should these become genuinely unused. The key here is that we _are_ using the value, we ignore it but that is a deliberate action. This patch adds a nested local variable within the alloc_bootmem_node helper to which the pgdat parameter is assigned making it 'used'. The nested local is marked __attribute__ ((unused)) to silence this same warning for it. Signed-off-by: NAndy Whitcroft <apw@shadowen.org> Cc: Christoph Lameter <clameter@engr.sgi.com> Cc: Andi Kleen <ak@suse.de> Signed-off-by: NAndrew Morton <akpm@osdl.org> Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
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由 Andy Whitcroft 提交于
NUMA node ids are passed as either int or unsigned int almost exclusivly page_to_nid and zone_to_nid both return unsigned long. This is a throw back to when page_to_nid was a #define and was thus exposing the real type of the page flags field. In addition to fixing up the definitions of page_to_nid and zone_to_nid I audited the users of these functions identifying the following incorrect uses: 1) mm/page_alloc.c show_node() -- printk dumping the node id, 2) include/asm-ia64/pgalloc.h pgtable_quicklist_free() -- comparison against numa_node_id() which returns an int from cpu_to_node(), and 3) mm/mpolicy.c check_pte_range -- used as an index in node_isset which uses bit_set which in generic code takes an int. Signed-off-by: NAndy Whitcroft <apw@shadowen.org> Cc: Christoph Lameter <clameter@engr.sgi.com> Cc: "Luck, Tony" <tony.luck@intel.com> Signed-off-by: NAndrew Morton <akpm@osdl.org> Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
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由 Christoph Lameter 提交于
drain_node_pages() currently drains the complete pageset of all pages. If there are a large number of pages in the queues then we may hold off interrupts for too long. Duplicate the method used in free_hot_cold_page. Only drain pcp->batch pages at one time. Signed-off-by: NChristoph Lameter <clameter@sgi.com> Signed-off-by: NAndrew Morton <akpm@osdl.org> Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
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由 Christoph Lameter 提交于
Remove all uses of kmem_cache_t (the most were left in slab.h). The typedef for kmem_cache_t is then only necessary for other kernel subsystems. Add a comment to that effect. Signed-off-by: NChristoph Lameter <clameter@sgi.com> Signed-off-by: NAndrew Morton <akpm@osdl.org> Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
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由 Christoph Lameter 提交于
The names_cachep is used for getname() and putname(). So lets put it into fs.h near those two definitions. Signed-off-by: NChristoph Lameter <clameter@sgi.com> Signed-off-by: NAndrew Morton <akpm@osdl.org> Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
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由 Christoph Lameter 提交于
fs_cachep is only used in kernel/exit.c and in kernel/fork.c. It is used to store fs_struct items so it should be placed in linux/fs_struct.h Signed-off-by: NChristoph Lameter <clameter@sgi.com> Signed-off-by: NAndrew Morton <akpm@osdl.org> Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
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由 Christoph Lameter 提交于
filp_cachep is only used in fs/file_table.c and in fs/dcache.c where it is defined. Move it to related definitions in linux/file.h. Signed-off-by: NChristoph Lameter <clameter@sgi.com> Signed-off-by: NAndrew Morton <akpm@osdl.org> Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
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由 Christoph Lameter 提交于
Proper place is in file.h since files_cachep uses are rated to file I/O. Signed-off-by: NChristoph Lameter <clameter@sgi.com> Signed-off-by: NAndrew Morton <akpm@osdl.org> Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
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由 Christoph Lameter 提交于
vm_area_cachep is used to store vm_area_structs. So move to mm.h. Signed-off-by: NChristoph Lameter <clameter@sgi.com> Signed-off-by: NAndrew Morton <akpm@osdl.org> Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
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由 Christoph Lameter 提交于
Move sighand_cachep definitioni to linux/signal.h The sighand cache is only used in fs/exec.c and kernel/fork.c. It is defined in kernel/fork.c but only used in fs/exec.c. The sighand_cachep is related to signal processing. So add the definition to signal.h. Signed-off-by: NChristoph Lameter <clameter@sgi.com> Signed-off-by: NAndrew Morton <akpm@osdl.org> Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
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由 Christoph Lameter 提交于
Remove bio_cachep from slab.h - it no longer exists. Signed-off-by: NChristoph Lameter <clameter@sgi.com> Signed-off-by: NAndrew Morton <akpm@osdl.org> Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
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由 Adrian Bunk 提交于
This patch makes the needlessly global "global_faults" static. Signed-off-by: NAdrian Bunk <bunk@stusta.de> Signed-off-by: NAndrew Morton <akpm@osdl.org> Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
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由 Christian Krafft 提交于
When booting a NUMA system with nodes that have no memory (eg by limiting memory), bootmem_alloc_core tried to find pages in an uninitialized bootmem_map. This caused a null pointer access. This fix adds a check, so that NULL is returned. That will enable the caller (bootmem_alloc_nopanic) to alloc memory on other without a panic. Signed-off-by: NChristian Krafft <krafft@de.ibm.com> Cc: Christoph Lameter <clameter@engr.sgi.com> Cc: Andy Whitcroft <apw@shadowen.org> Cc: Martin Bligh <mbligh@google.com> Signed-off-by: NAndrew Morton <akpm@osdl.org> Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
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由 Alan Stern 提交于
The patch (as824b) makes percpu_free() ignore NULL arguments, as one would expect for a deallocation routine. (Note that free_percpu is #defined as percpu_free in include/linux/percpu.h.) A few callers are updated to remove now-unneeded tests for NULL. A few other callers already seem to assume that passing a NULL pointer to percpu_free() is okay! The patch also removes an unnecessary NULL check in percpu_depopulate(). Signed-off-by: NAlan Stern <stern@rowland.harvard.edu> Signed-off-by: NAndrew Morton <akpm@osdl.org> Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
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由 Christoph Hellwig 提交于
Node-aware allocation of skbs for the receive path. Details: - __alloc_skb gets a new node argument and cals the node-aware slab functions with it. - netdev_alloc_skb passed the node number it gets from dev_to_node to it, everyone else passes -1 (any node) Signed-off-by: NChristoph Hellwig <hch@lst.de> Cc: Christoph Lameter <clameter@engr.sgi.com> Cc: "David S. Miller" <davem@davemloft.net> Signed-off-by: NAndrew Morton <akpm@osdl.org> Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
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由 Christoph Hellwig 提交于
For node-aware skb allocations we need information about the node in struct net_device or struct device. Davem suggested to put it into struct device which this patch does. In particular: - struct device gets a new int numa_node member if CONFIG_NUMA is set - there are two new helpers, dev_to_node and set_dev_node to transparently deal with the non-numa case - for pci devices the node-info is set to the value we get from pcibus_to_node. Note that for some architectures pcibus_to_node doesn't work yet at the time we call it currently. This is harmless and will just mean skb allocations aren't node-local on this architectures until the implementation of pcibus_to_node on these architectures have been updated (There are patches for x86 and x86_64 floating around) [akpm@osdl.org: cleanup] Signed-off-by: NChristoph Hellwig <hch@lst.de> Cc: Christoph Lameter <clameter@engr.sgi.com> Cc: Greg KH <greg@kroah.com> Signed-off-by: NAndrew Morton <akpm@osdl.org> Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
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由 Christoph Hellwig 提交于
We have variants of kmalloc and kmem_cache_alloc that leave leak tracking to the caller. This is used for subsystem-specific allocators like skb_alloc. To make skb_alloc node-aware we need similar routines for the node-aware slab allocator, which this patch adds. Note that the code is rather ugly, but it mirrors the non-node-aware code 1:1: [akpm@osdl.org: add module export] Signed-off-by: NChristoph Hellwig <hch@lst.de> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: NAndrew Morton <akpm@osdl.org> Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
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由 Suleiman Souhlal 提交于
It would be possible for /proc/swaps to not always print out the header: swapon /dev/hdc2 swapon /dev/hde2 swapoff /dev/hdc2 At this point /proc/swaps would not have a header. Signed-off-by: NSuleiman Souhlal <suleiman@google.com> Cc: Hugh Dickins <hugh@veritas.com> Signed-off-by: NAndrew Morton <akpm@osdl.org> Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
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由 Kirill Korotaev 提交于
OOM can panic due to the processes stuck in __alloc_pages() doing infinite rebalance loop while no memory can be reclaimed. OOM killer tries to kill some processes, but unfortunetaly, rebalance label was moved by someone below the TIF_MEMDIE check, so buddy allocator doesn't see that process is OOM-killed and it can simply fail the allocation :/ Observed in reality on RHEL4(2.6.9)+OpenVZ kernel when a user doing some memory allocation tricks triggered OOM panic. Signed-off-by: NDenis Lunev <den@sw.ru> Signed-off-by: NKirill Korotaev <dev@openvz.org> Cc: Nick Piggin <nickpiggin@yahoo.com.au> Signed-off-by: NAndrew Morton <akpm@osdl.org> Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
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由 Rik Bobbaers 提交于
mm is defined as vma->vm_mm, so use that. Acked-by: NHugh Dickins <hugh@veritas.com> Signed-off-by: NAndrew Morton <akpm@osdl.org> Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
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由 Guillem Jover 提交于
Currently a user process cannot rise its own oom_adj value (i.e. unprotecting itself from the OOM killer). As this value is stored in the task structure it gets inherited and the unprivileged childs will be unable to rise it. The EPERM will be handled by the generic proc fs layer, as only processes with the proper caps or the owner of the process will be able to write to the file. So we allow only the processes with CAP_SYS_RESOURCE to lower the value, otherwise it will get an EACCES which seems more appropriate than EPERM. Signed-off-by: NGuillem Jover <guillem.jover@nokia.com> Acked-by: NAndrea Arcangeli <andrea@novell.com> Signed-off-by: NAndrew Morton <akpm@osdl.org> Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
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由 Jeremy Fitzhardinge 提交于
kunmap_atomic() will call kpte_clear_flush with vaddr/ptep arguments which don't correspond if the vaddr is just a normal lowmem address (ie, not in the KMAP area). This patch makes sure that the pte is only cleared if kmap area was actually used for the mapping. Signed-off-by: NJeremy Fitzhardinge <jeremy@xensource.com> Signed-off-by: NRusty Russell <rusty@rustcorp.com.au> Cc: Zachary Amsden <zach@vmware.com> Signed-off-by: NAndrew Morton <akpm@osdl.org> Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
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由 Peter Zijlstra 提交于
Make kmap_atomic/kunmap_atomic denote a pagefault disabled scope. All non trivial implementations already do this anyway. Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: NNick Piggin <npiggin@suse.de> Signed-off-by: NAndrew Morton <akpm@osdl.org> Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
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由 Peter Zijlstra 提交于
Introduce pagefault_{disable,enable}() and use these where previously we did manual preempt increments/decrements to make the pagefault handler do the atomic thing. Currently they still rely on the increased preempt count, but do not rely on the disabled preemption, this might go away in the future. (NOTE: the extra barrier() in pagefault_disable might fix some holes on machines which have too many registers for their own good) [heiko.carstens@de.ibm.com: s390 fix] Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: NNick Piggin <npiggin@suse.de> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: NAndrew Morton <akpm@osdl.org> Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
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由 Peter Zijlstra 提交于
In light of the recent pagefault and filemap_copy_from_user work I've gone through all the arch pagefault handlers to make sure the inc_preempt_count() 'feature' works as expected. Several sections of code (including the new filemap_copy_from_user) rely on the fact that faults do not take locks under increased preempt count. arch/x86_64 - good arch/powerpc - good arch/cris - fixed arch/i386 - good arch/parisc - fixed arch/sh - good arch/sparc - good arch/s390 - good arch/m68k - fixed arch/ppc - good arch/alpha - fixed arch/mips - good arch/sparc64 - good arch/ia64 - good arch/arm - fixed arch/um - good arch/avr32 - good arch/h8300 - NA arch/m32r - good arch/v850 - good arch/frv - fixed arch/m68knommu - NA arch/arm26 - fixed arch/sh64 - fixed arch/xtensa - good Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: NNick Piggin <npiggin@suse.de> Signed-off-by: NAndrew Morton <akpm@osdl.org> Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
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由 Paul Menage 提交于
When using numa=fake on non-NUMA hardware there is no benefit to having the alien caches, and they consume much memory. Add a kernel boot option to disable them. Christoph sayeth "This is good to have even on large NUMA. The problem is that the alien caches grow by the square of the size of the system in terms of nodes." Cc: Christoph Lameter <clameter@engr.sgi.com> Cc: Pekka Enberg <penberg@cs.helsinki.fi> Cc: Manfred Spraul <manfred@colorfullife.com> Signed-off-by: NAndrew Morton <akpm@osdl.org> Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
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由 Ravikiran G Thirumalai 提交于
Here's an attempt towards doing away with lock_cpu_hotplug in the slab subsystem. This approach also fixes a bug which shows up when cpus are being offlined/onlined and slab caches are being tuned simultaneously. http://marc.theaimsgroup.com/?l=linux-kernel&m=116098888100481&w=2 The patch has been stress tested overnight on a 2 socket 4 core AMD box with repeated cpu online and offline, while dbench and kernbench process are running, and slab caches being tuned at the same time. There were no lockdep warnings either. (This test on 2,6.18 as 2.6.19-rc crashes at __drain_pages http://marc.theaimsgroup.com/?l=linux-kernel&m=116172164217678&w=2 ) The approach here is to hold cache_chain_mutex from CPU_UP_PREPARE until CPU_ONLINE (similar in approach as worqueue_mutex) . Slab code sensitive to cpu_online_map (kmem_cache_create, kmem_cache_destroy, slabinfo_write, __cache_shrink) is already serialized with cache_chain_mutex. (This patch lengthens cache_chain_mutex hold time at kmem_cache_destroy to cover this). This patch also takes the cache_chain_sem at kmem_cache_shrink to protect sanity of cpu_online_map at __cache_shrink, as viewed by slab. (kmem_cache_shrink->__cache_shrink->drain_cpu_caches). But, really, kmem_cache_shrink is used at just one place in the acpi subsystem! Do we really need to keep kmem_cache_shrink at all? Another note. Looks like a cpu hotplug event can send CPU_UP_CANCELED to a registered subsystem even if the subsystem did not receive CPU_UP_PREPARE. This could be due to a subsystem registered for notification earlier than the current subsystem crapping out with NOTIFY_BAD. Badness can occur with in the CPU_UP_CANCELED code path at slab if this happens (The same would apply for workqueue.c as well). To overcome this, we might have to use either a) a per subsystem flag and avoid handling of CPU_UP_CANCELED, or b) Use a special notifier events like LOCK_ACQUIRE/RELEASE as Gautham was using in his experiments, or c) Do not send CPU_UP_CANCELED to a subsystem which did not receive CPU_UP_PREPARE. I would prefer c). Signed-off-by: NRavikiran Thirumalai <kiran@scalex86.org> Signed-off-by: NShai Fultheim <shai@scalex86.org> Signed-off-by: NAndrew Morton <akpm@osdl.org> Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
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由 Kevin Hilman 提交于
When CONFIG_SLAB_DEBUG is used in combination with ARCH_SLAB_MINALIGN, some debug flags should be disabled which depend on BYTES_PER_WORD alignment. The disabling of these debug flags is not properly handled when BYTES_PER_WORD < ARCH_SLAB_MEMALIGN < cache_line_size() This patch fixes that and also adds an alignment check to cache_alloc_debugcheck_after() when ARCH_SLAB_MINALIGN is used. Signed-off-by: NKevin Hilman <khilman@mvista.com> Cc: Pekka Enberg <penberg@cs.helsinki.fi> Cc: Christoph Lameter <clameter@engr.sgi.com> Cc: Manfred Spraul <manfred@colorfullife.com> Signed-off-by: NAndrew Morton <akpm@osdl.org> Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
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由 Chen, Kenneth W 提交于
Imprecise RSS accounting is an irritating ill effect with pt sharing. After consulted with several VM experts, I have tried various methods to solve that problem: (1) iterate through all mm_structs that share the PT and increment count; (2) keep RSS count in page table structure and then sum them up at reporting time. None of the above methods yield any satisfactory implementation. Since process RSS accounting is pure information only, I propose we don't count them at all for hugetlb page. rlimit has such field, though there is absolutely no enforcement on limiting that resource. One other method is to account all RSS at hugetlb mmap time regardless they are faulted or not. I opt for the simplicity of no accounting at all. Hugetlb page are special, they are reserved up front in global reservation pool and is not reclaimable. From physical memory resource point of view, it is already consumed regardless whether there are users using them. If the concern is that RSS can be used to control resource allocation, we already can specify hugetlb fs size limit and sysadmin can enforce that at mount time. Combined with the two points mentioned above, I fail to see if there is anything got affected because of this patch. Signed-off-by: NKen Chen <kenneth.w.chen@intel.com> Acked-by: NHugh Dickins <hugh@veritas.com> Cc: Dave McCracken <dmccr@us.ibm.com> Cc: William Lee Irwin III <wli@holomorphy.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: David Gibson <david@gibson.dropbear.id.au> Cc: Adam Litke <agl@us.ibm.com> Cc: Paul Mundt <lethal@linux-sh.org> Cc: "David S. Miller" <davem@davemloft.net> Signed-off-by: NAndrew Morton <akpm@osdl.org> Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
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由 Chen, Kenneth W 提交于
Following up with the work on shared page table done by Dave McCracken. This set of patch target shared page table for hugetlb memory only. The shared page table is particular useful in the situation of large number of independent processes sharing large shared memory segments. In the normal page case, the amount of memory saved from process' page table is quite significant. For hugetlb, the saving on page table memory is not the primary objective (as hugetlb itself already cuts down page table overhead significantly), instead, the purpose of using shared page table on hugetlb is to allow faster TLB refill and smaller cache pollution upon TLB miss. With PT sharing, pte entries are shared among hundreds of processes, the cache consumption used by all the page table is smaller and in return, application gets much higher cache hit ratio. One other effect is that cache hit ratio with hardware page walker hitting on pte in cache will be higher and this helps to reduce tlb miss latency. These two effects contribute to higher application performance. Signed-off-by: NKen Chen <kenneth.w.chen@intel.com> Acked-by: NHugh Dickins <hugh@veritas.com> Cc: Dave McCracken <dmccr@us.ibm.com> Cc: William Lee Irwin III <wli@holomorphy.com> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: David Gibson <david@gibson.dropbear.id.au> Cc: Adam Litke <agl@us.ibm.com> Cc: Paul Mundt <lethal@linux-sh.org> Cc: "David S. Miller" <davem@davemloft.net> Signed-off-by: NAndrew Morton <akpm@osdl.org> Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
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