- 05 Aug, 2011 5 commits
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Anton Blanchard authored
I hit an oops at boot on the first instruction of timer_cpu_notify: NIP [c000000000722f88] .timer_cpu_notify+0x0/0x388 The code should look like: c000000000722f78: eb e9 00 30 ld r31,48(r9) c000000000722f7c: 2f bf 00 00 cmpdi cr7,r31,0 c000000000722f80: 40 9e ff 44 bne+ cr7,c000000000722ec4 c000000000722f84: 4b ff ff 74 b c000000000722ef8 c000000000722f88 <.timer_cpu_notify>: c000000000722f88: 7c 08 02 a6 mflr r0 c000000000722f8c: 2f a4 00 07 cmpdi cr7,r4,7 c000000000722f90: fb c1 ff f0 std r30,-16(r1) c000000000722f94: fb 61 ff d8 std r27,-40(r1) But the oops output shows: eb61ffd8 eb81ffe0 eba1ffe8 ebc1fff0 7c0803a6 ebe1fff8 4e800020 00000000 ebe90030 c0000000 00ad0a28 00000000 2fa40007 fbc1fff0 fb61ffd8 So we scribbled over our instructions with c000000000ad0a28, which is an address inside the jump_table ELF section. It turns out the jump_table section is only aligned to 8 bytes but we are aligning our entries within the section to 16 bytes. This means our entries are offset from the table: c000000000acd4a8 <__start___jump_table>: ... c000000000ad0a10: c0 00 00 00 lfs f0,0(0) c000000000ad0a14: 00 70 cd 5c .long 0x70cd5c c000000000ad0a18: c0 00 00 00 lfs f0,0(0) c000000000ad0a1c: 00 70 cd 90 .long 0x70cd90 c000000000ad0a20: c0 00 00 00 lfs f0,0(0) c000000000ad0a24: 00 ac a4 20 .long 0xaca420 And the jump table sort code gets very confused and writes into the wrong spot. Remove the alignment, and also remove the padding since we it saves some space and we shouldn't need it. Signed-off-by:
Anton Blanchard <anton@samba.org> Signed-off-by:
Benjamin Herrenschmidt <benh@kernel.crashing.org>
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Anton Blanchard authored
Add a newline to the panic messages in make_room. Also fix a comment that suggested our chunk size is 4Mb. It's 1MB. Signed-off-by:
Anton Blanchard <anton@samba.org> Signed-off-by:
Benjamin Herrenschmidt <benh@kernel.crashing.org>
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Anton Blanchard authored
I have a box that fails in OF during boot with: DEFAULT CATCH!, exception-handler=fff00400 at %SRR0: 49424d2c4c6f6768 %SRR1: 800000004000b002 ie "IBM,Logh". OF got corrupted with a device tree string. Looking at make_room and alloc_up, we claim the first chunk (1 MB) but we never claim any more. mem_end is always set to alloc_top which is the top of our available address space, guaranteeing we will never call alloc_up and claim more memory. Also alloc_up wasn't setting alloc_bottom to the bottom of the available address space. This doesn't help the box to boot, but we at least fail with an obvious error. We could relocate the device tree in a future patch. Signed-off-by:
Anton Blanchard <anton@samba.org> Cc: <stable@kernel.org> Signed-off-by:
Benjamin Herrenschmidt <benh@kernel.crashing.org>
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Scott Wood authored
Commit af9eef3c caused cpu_setup to see the_cpu_spec, rather than the source struct. However, on 32-bit, the return value of identify_cpu was being used for feature fixups, and identify_cpu was returning the source struct. So if cpu_setup patches the feature bits, the update won't affect the fixups. Signed-off-by:
Scott Wood <scottwood@freescale.com> Signed-off-by:
Benjamin Herrenschmidt <benh@kernel.crashing.org>
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Scott Wood authored
Add a cast in case the caller passes in a different type, as it would if mtspr/mtmsr were functions. Previously, if a 64-bit type was passed in on 32-bit, GCC would bind the constraint to a pair of registers, and would substitute the first register in the pair in the asm code. This corresponds to the upper half of the 64-bit register, which is generally not the desired behavior. Signed-off-by:
Scott Wood <scottwood@freescale.com> Signed-off-by:
Benjamin Herrenschmidt <benh@kernel.crashing.org>
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- 04 Aug, 2011 35 commits
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git://git.secretlab.ca/git/linux-2.6Linus Torvalds authored
* 'devicetree/merge' of git://git.secretlab.ca/git/linux-2.6: Revert "dt: add of_alias_scan and of_alias_get_id" dt: remove of_alias_get_id() reference
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git://git.kernel.org/pub/scm/linux/kernel/git/jejb/parisc-2.6Linus Torvalds authored
* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/parisc-2.6: [PARISC] wire up sendmmsg syscall [PARISC] fix return type of __atomic64_add_return [PARISC] Fix futex support
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git://git390.marist.edu/pub/scm/linux-2.6Linus Torvalds authored
* 'for-linus' of git://git390.marist.edu/pub/scm/linux-2.6: [S390] signal: use set_restore_sigmask() helper [S390] smp: remove pointless comments in startup_secondary() [S390] qdio: Use kstrtoul_from_user [S390] sclp_async: Use kstrtoul_from_user [S390] exec: remove redundant set_fs(USER_DS) [S390] cpu hotplug: on cpu start wait until being marked active [S390] signal: convert to use set_current_blocked() [S390] asm offsets: fix coding style [S390] Add support for IBM zEnterprise 114 [S390] dasd: check if raw track access is supported [S390] Use diagnose 308 for system reset [S390] Export store_status() function [S390] dasd: use vmalloc for statistics input buffer [S390] Add PSW restart shutdown trigger [S390] missing return in page_table_alloc_pgste [S390] qdio: 2nd stage retry on SIGA-W busy conditions
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Arnaud Lacombe authored
While `pci_eisa_driver' still refer `pci_eisa_init', the .probe() function should not be called after init memory release, as pointed out by commit 74b9a297. The structure is still referenced in the drivers subsystem, and can be accesseed through sysfs, so the modpost warning is a false positive. Mark it as such. In the same time, the warning referenced in 005bdad7 did only mention `pci_eisa_driver', not `pci_eisa_pci_tbl', so remove its marking. Broken-by: Arnaud Lacombe <lacombar@gmail.com> (in 005bdad7) Reported-by:
Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp> Signed-off-by:
Arnaud Lacombe <lacombar@gmail.com> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org>
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Grant Likely authored
This reverts commit 750f463a. of_alias_* still needs work to be generalized for 'promtree' dt platforms, and to no implicitly create entries for available ids. Signed-off-by:
Grant Likely <grant.likely@secretlab.ca>
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Grant Likely authored
of_alias_get_id() is broken and being reverted. Remove the reference to it and replace with a single incrementing id number. There is no risk of regression here on the imx driver since the imx change to use of_alias_get_id() is commit 22698aa2, "serial/imx: add device tree probe support" which is new for v3.1, and it won't get used unless CONFIG_OF is enabled and the board is booted using a device tree. A single incrementing integer is sufficient for now. Signed-off-by:
Grant Likely <grant.likely@secretlab.ca> Acked-by:
Shawn Guo <shawn.guo@linaro.org>
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Linus Torvalds authored
The core device layer sends tons of uevent notifications for each device it finds, and if the kernel has been built with a non-empty CONFIG_UEVENT_HELPER_PATH that will make us try to execute the usermode helper binary for all these events very early in the boot. Not only won't the root filesystem even be mounted at that point, we literally won't have necessarily even initialized all the process handling data structures at that point, which causes no end of silly problems even when the usermode helper doesn't actually succeed in executing. So just use our existing infrastructure to disable the usermodehelpers to make the kernel start out with them disabled. We enable them when we've at least initialized stuff a bit. Problems related to an uninitialized init_ipc_ns.ids[IPC_SHM_IDS].rw_mutex reported by various people. Reported-by:
Manuel Lauss <manuel.lauss@googlemail.com> Reported-by:
Richard Weinberger <richard@nod.at> Reported-by:
Marc Zyngier <maz@misterjones.org> Acked-by:
Kay Sievers <kay.sievers@vrfy.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Vasiliy Kulikov <segoon@openwall.com> Cc: Greg KH <greg@kroah.com> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org>
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Linus Torvalds authored
Dmitry Kasatkin reports: "kernel-devel package with kernel headers have no <include/xen> directory if XEN is disabled. Modules which inclide asm/io.h won't compile. XEN related content is behind the CONFIG_XEN flag in the io.h. And <xen/xen.h> should be also behind CONFIG_XEN flag." So move the include of <xen/xen.h> down into the section that is conditional on CONFIG_XEN. Reported-by:
Dmitry Kasatkin <dmitry.kasatkin@intel.com> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/dtor/inputLinus Torvalds authored
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input: Input: ad7879 - fix deficient device disable Input: gpio_keys - fix two typos in devicetree documentation Input: mma8450 - add device tree probe support Input: gpio_keys - return proper error code if memory allocation fails Input: lm8323 - add missing device_remove_file for dev_attr_time Input: tegra-kbc - fix computation of polling time Input: kxtj9 - explicitly include module.h Input: psmouse - hgpk.c needs module.h
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git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-idle-2.6Linus Torvalds authored
* 'idle-release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-idle-2.6: cpuidle: stop depending on pm_idle x86 idle: move mwait_idle_with_hints() to where it is used cpuidle: replace xen access to x86 pm_idle and default_idle cpuidle: create bootparam "cpuidle.off=1" mrst_pmu: driver for Intel Moorestown Power Management Unit
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git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6Linus Torvalds authored
* 'apei-release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6: ACPI, APEI, EINJ Param support is disabled by default APEI GHES: 32-bit buildfix ACPI: APEI build fix ACPI, APEI, GHES: Add hardware memory error recovery support HWPoison: add memory_failure_queue() ACPI, APEI, GHES, Error records content based throttle ACPI, APEI, GHES, printk support for recoverable error via NMI lib, Make gen_pool memory allocator lockless lib, Add lock-less NULL terminated single list Add Kconfig option ARCH_HAVE_NMI_SAFE_CMPXCHG ACPI, APEI, Add WHEA _OSC support ACPI, APEI, Add APEI bit support in generic _OSC call ACPI, APEI, GHES, Support disable GHES at boot time ACPI, APEI, GHES, Prevent GHES to be built as module ACPI, APEI, Use apei_exec_run_optional in APEI EINJ and ERST ACPI, APEI, Add apei_exec_run_optional ACPI, APEI, GHES, Do not ratelimit fatal error printk before panic ACPI, APEI, ERST, Fix erst-dbg long record reading issue ACPI, APEI, ERST, Prevent erst_dbg from loading if ERST is disabled
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git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pendingLinus Torvalds authored
* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending: tcm_fc: Handle DDP/SW fc_frame_payload_get failures in ft_recv_write_data target: Fix bug for transport_generic_wait_for_tasks with direct operation target: iscsi_target depends on NET target: Fix WRITE_SAME_16 lba assignment breakage MAINTAINERS: Add target-devel list for drivers/target/ iscsi-target: Fix CONFIG_SMP=n and CONFIG_MODULES=n build failure iscsi-target: Fix snprintf usage with MAX_PORTAL_LEN iscsi-target: Fix uninitialized usage of cmd->pad_bytes iscsi-target: strlen() doesn't count the terminator iscsi-target: Fix NULL dereference on allocation failure
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git://git.secretlab.ca/git/linux-2.6Linus Torvalds authored
* 'devicetree/next' of git://git.secretlab.ca/git/linux-2.6: dt: add of_alias_scan and of_alias_get_id
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git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4Linus Torvalds authored
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: ext4: use kzalloc in ext4_kzalloc()
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Vasiliy Kulikov authored
We may optimistically check .in_use == 0 without holding the rw_mutex: it's the common case, and if it's zero, there certainly won't be any segments associated with us. After taking the lock, the idr_for_each() will do the right thing, so we could now drop the re-check inside the lock without any real cost. But it won't hurt. Signed-off-by:
Vasiliy Kulikov <segoon@openwall.com> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org>
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Vasiliy Kulikov authored
Commit 4c677e2e ("shm: optimize locking and ipc_namespace getting") introduced a copy-paste bug. Due to the bug cycle optimizations were disabled. Signed-off-by:
Vasiliy Kulikov <segoon@openwall.com> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org>
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Robert P. J. Day authored
Expand the fs/Kconfig "help" info to clarify why it's a bad idea to deselect the TMPFS_POSIX_ACL config variable. Signed-off-by:
Robert P. J. Day <rpjday@crashcourse.ca> Acked-by:
Randy Dunlap <rdunlap@xenotime.net> Acked-by:
Hugh Dickins <hughd@google.com> Signed-off-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org>
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Hugh Dickins authored
Make the radix_tree exceptional cases, mostly in filemap.c, clearer. It's hard to devise a suitable snappy name that illuminates the use by shmem/tmpfs for swap, while keeping filemap/pagecache/radix_tree generality. And akpm points out that /* radix_tree_deref_retry(page) */ comments look like calls that have been commented out for unknown reason. Skirt the naming difficulty by rearranging these blocks to handle the transient radix_tree_deref_retry(page) case first; then just explain the remaining shmem/tmpfs swap case in a comment. Signed-off-by:
Hugh Dickins <hughd@google.com> Signed-off-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org>
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Hugh Dickins authored
We have already acknowledged that swapoff of a tmpfs file is slower than it was before conversion to the generic radix_tree: a little slower there will be acceptable, if the hotter paths are faster. But it was a shock to find swapoff of a 500MB file 20 times slower on my laptop, taking 10 minutes; and at that rate it significantly slows down my testing. Now, most of that turned out to be overhead from PROVE_LOCKING and PROVE_RCU: without those it was only 4 times slower than before; and more realistic tests on other machines don't fare as badly. I've tried a number of things to improve it, including tagging the swap entries, then doing lookup by tag: I'd expected that to halve the time, but in practice it's erratic, and often counter-productive. The only change I've so far found to make a consistent improvement, is to short-circuit the way we go back and forth, gang lookup packing entries into the array supplied, then shmem scanning that array for the target entry. Scanning in place doubles the speed, so it's now only twice as slow as before (or three times slower when the PROVEs are on). So, add radix_tree_locate_item() as an expedient, once-off, single-caller hack to do the lookup directly in place. #ifdef it on CONFIG_SHMEM and CONFIG_SWAP, as much to document its limited applicability as save space in other configurations. And, sadly, #include sched.h for cond_resched(). Signed-off-by:
Hugh Dickins <hughd@google.com> Signed-off-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org>
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Hugh Dickins authored
Remove PageSwapBacked (!page_is_file_cache) cases from add_to_page_cache_locked() and add_to_page_cache_lru(): those pages now go through shmem_add_to_page_cache(). Remove a comment on maximum tmpfs size from fsstack_copy_inode_size(), and add a comment on swap entries to invalidate_mapping_pages(). And mincore_page() uses find_get_page() on what might be shmem or a tmpfs file: allow for a radix_tree_exceptional_entry(), and proceed to find_get_page() on swapper_space if so (oh, swapper_space needs #ifdef). Signed-off-by:
Hugh Dickins <hughd@google.com> Acked-by:
Rik van Riel <riel@redhat.com> Signed-off-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org>
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Hugh Dickins authored
But we've not yet removed the old swp_entry_t i_direct[16] from shmem_inode_info. That's because it was still being shared with the inline symlink. Remove it now (saving 64 or 128 bytes from shmem inode size), and use kmemdup() for short symlinks, say, those up to 128 bytes. I wonder why mpol_free_shared_policy() is done in shmem_destroy_inode() rather than shmem_evict_inode(), where we usually do such freeing? I guess it doesn't matter, and I'm not into NUMA mpol testing right now. Signed-off-by:
Hugh Dickins <hughd@google.com> Acked-by:
Rik van Riel <riel@redhat.com> Reviewed-by:
Pekka Enberg <penberg@kernel.org> Signed-off-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org>
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Hugh Dickins authored
Convert shmem_writepage() to use shmem_delete_from_page_cache() to use shmem_radix_tree_replace() to substitute swap entry for page pointer atomically in the radix tree. As with shmem_add_to_page_cache(), it's not entirely satisfactory to be copying such code from delete_from_swap_cache, but again judged easier to sell than making its other callers go through the extras. Remove the toy implementation's shmem_put_swap() and shmem_get_swap(), now unreferenced, and the hack to disable swap: it's now good to go. The way things have worked out, info->lock no longer helps to guard the shmem_swaplist: we increment swapped under shmem_swaplist_mutex only. That global mutex exclusion between shmem_writepage() and shmem_unuse() is not pretty, and we ought to find another way; but it's been forced on us by recent race discoveries, not a consequence of this patchset. And what has become of the WARN_ON_ONCE(1) free_swap_and_cache() if a swap entry was found already present? That's no longer possible, the (unknown) one inserting this page into filecache would hit the swap entry occupying that slot. Signed-off-by:
Hugh Dickins <hughd@google.com> Acked-by:
Rik van Riel <riel@redhat.com> Signed-off-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org>
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Hugh Dickins authored
Remove mem_cgroup_shmem_charge_fallback(): it was only required when we had to move swappage to filecache with GFP_NOWAIT. Remove the GFP_NOWAIT special case from mem_cgroup_cache_charge(), by moving its call out from shmem_add_to_page_cache() to two of thats three callers. But leave it doing mem_cgroup_uncharge_cache_page() on error: although asymmetrical, it's easier for all 3 callers to handle. These two changes would also be appropriate if anyone were to start using shmem_read_mapping_page_gfp() with GFP_NOWAIT. Remove mem_cgroup_get_shmem_target(): mc_handle_file_pte() can test radix_tree_exceptional_entry() to get what it needs for itself. Signed-off-by:
Hugh Dickins <hughd@google.com> Acked-by:
Rik van Riel <riel@redhat.com> Signed-off-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org>
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Hugh Dickins authored
Convert shmem_getpage_gfp(), the engine-room of shmem, to expect page or swap entry returned from radix tree by find_lock_page(). Whereas the repetitive old method proceeded mainly under info->lock, dropping and repeating whenever one of the conditions needed was not met, now we can proceed without it, leaving shmem_add_to_page_cache() to check for a race. This way there is no need to preallocate a page, no need for an early radix_tree_preload(), no need for mem_cgroup_shmem_charge_fallback(). Move the error unwinding down to the bottom instead of repeating it throughout. ENOSPC handling is a little different from before: there is no longer any race between find_lock_page() and finding swap, but we can arrive at ENOSPC before calling shmem_recalc_inode(), which might occasionally discover freed space. Be stricter to check i_size before returning. info->lock is used for little but alloced, swapped, i_blocks updates. Move i_blocks updates out from under the max_blocks check, so even an unlimited size=0 mount can show accurate du. Signed-off-by:
Hugh Dickins <hughd@google.com> Acked-by:
Rik van Riel <riel@redhat.com> Signed-off-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org>
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Hugh Dickins authored
Convert shmem_unuse_inode() to use a lockless gang lookup of the radix tree, searching for matching swap. This is somewhat slower than the old method: because of repeated radix tree descents, because of copying entries up, but probably most because the old method noted and skipped once a vector page was cleared of swap. Perhaps we can devise a use of radix tree tagging to achieve that later. shmem_add_to_page_cache() uses shmem_radix_tree_replace() to compensate for the lockless lookup by checking that the expected entry is in place, under lock. It is not very satisfactory to be copying this much from add_to_page_cache_locked(), but I think easier to sell than insisting that every caller of add_to_page_cache*() go through the extras. Signed-off-by:
Hugh Dickins <hughd@google.com> Acked-by:
Rik van Riel <riel@redhat.com> Signed-off-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org>
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Hugh Dickins authored
Disable the toy swapping implementation in shmem_writepage() - it's hard to support two schemes at once - and convert shmem_truncate_range() to a lockless gang lookup of swap entries along with pages, freeing both. Since the second loop tightens its noose until all entries of either kind have been squeezed out (and we shall make sure that there's not an instant when neither is visible), there is no longer a need for yet another pass below. shmem_radix_tree_replace() compensates for the lockless lookup by checking that the expected entry is in place, under lock, before replacing it. Here it just deletes, but will be used in later patches to substitute swap entry for page or page for swap entry. Signed-off-by:
Hugh Dickins <hughd@google.com> Acked-by:
Rik van Riel <riel@redhat.com> Signed-off-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org>
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Hugh Dickins authored
Bring truncate.c's code for truncate_inode_pages_range() inline into shmem_truncate_range(), replacing its first call (there's a followup call below, but leave that one, it will disappear next). Don't play with it yet, apart from leaving out the cleancache flush, and (importantly) the nrpages == 0 skip, and moving shmem_setattr()'s partial page preparation into its partial page handling. Signed-off-by:
Hugh Dickins <hughd@google.com> Acked-by:
Rik van Riel <riel@redhat.com> Signed-off-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org>
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Hugh Dickins authored
While it's at its least, make a number of boring nitpicky cleanups to shmem.c, mostly for consistency of variable naming. Things like "swap" instead of "entry", "pgoff_t index" instead of "unsigned long idx". And since everything else here is prefixed "shmem_", better change init_tmpfs() to shmem_init(). Signed-off-by:
Hugh Dickins <hughd@google.com> Acked-by:
Rik van Riel <riel@redhat.com> Signed-off-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org>
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Hugh Dickins authored
The maximum size of a shmem/tmpfs file has been limited by the maximum size of its triple-indirect swap vector. With 4kB page size, maximum filesize was just over 2TB on a 32-bit kernel, but sadly one eighth of that on a 64-bit kernel. (With 8kB page size, maximum filesize was just over 4TB on a 64-bit kernel, but 16TB on a 32-bit kernel, MAX_LFS_FILESIZE being then more restrictive than swap vector layout.) It's a shame that tmpfs should be more restrictive than ramfs, and this limitation has now been noticed. Add another level to the swap vector? No, it became obscure and hard to maintain, once I complicated it to make use of highmem pages nine years ago: better choose another way. Surely, if 2.4 had had the radix tree pagecache introduced in 2.5, then tmpfs would never have invented its own peculiar radix tree: we would have fitted swap entries into the common radix tree instead, in much the same way as we fit swap entries into page tables. And why should each file have a separate radix tree for its pages and for its swap entries? The swap entries are required precisely where and when the pages are not. We want to put them together in a single radix tree: which can then avoid much of the locking which was needed to prevent them from being exchanged underneath us. This also avoids the waste of memory devoted to swap vectors, first in the shmem_inode itself, then at least two more pages once a file grew beyond 16 data pages (pages accounted by df and du, but not by memcg). Allocated upfront, to avoid allocation when under swapping pressure, but pure waste when CONFIG_SWAP is not set - I have never spattered around the ifdefs to prevent that, preferring this move to sharing the common radix tree instead. There are three downsides to sharing the radix tree. One, that it binds tmpfs more tightly to the rest of mm, either requiring knowledge of swap entries in radix tree there, or duplication of its code here in shmem.c. I believe that the simplications and memory savings (and probable higher performance, not yet measured) justify that. Two, that on HIGHMEM systems with SWAP enabled, it's the lowmem radix nodes that cannot be freed under memory pressure - whereas before it was the less precious highmem swap vector pages that could not be freed. I'm hoping that 64-bit has now been accessible for long enough, that the highmem argument has grown much less persuasive. Three, that swapoff is slower than it used to be on tmpfs files, since it's using a simple generic mechanism not tailored to it: I find this noticeable, and shall want to improve, but maybe nobody else will notice. So... now remove most of the old swap vector code from shmem.c. But, for the moment, keep the simple i_direct vector of 16 pages, with simple accessors shmem_put_swap() and shmem_get_swap(), as a toy implementation to help mark where swap needs to be handled in subsequent patches. Signed-off-by:
Hugh Dickins <hughd@google.com> Acked-by:
Rik van Riel <riel@redhat.com> Signed-off-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org>
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Hugh Dickins authored
If swap entries are to be stored along with struct page pointers in a radix tree, they need to be distinguished as exceptional entries. Most of the handling of swap entries in radix tree will be contained in shmem.c, but a few functions in filemap.c's common code need to check for their appearance: find_get_page(), find_lock_page(), find_get_pages() and find_get_pages_contig(). So as not to slow their fast paths, tuck those checks inside the existing checks for unlikely radix_tree_deref_slot(); except for find_lock_page(), where it is an added test. And make it a BUG in find_get_pages_tag(), which is not applied to tmpfs files. A part of the reason for eliminating shmem_readpage() earlier, was to minimize the places where common code would need to allow for swap entries. The swp_entry_t known to swapfile.c must be massaged into a slightly different form when stored in the radix tree, just as it gets massaged into a pte_t when stored in page tables. In an i386 kernel this limits its information (type and page offset) to 30 bits: given 32 "types" of swapfile and 4kB pagesize, that's a maximum swapfile size of 128GB. Which is less than the 512GB we previously allowed with X86_PAE (where the swap entry can occupy the entire upper 32 bits of a pte_t), but not a new limitation on 32-bit without PAE; and there's not a new limitation on 64-bit (where swap filesize is already limited to 16TB by a 32-bit page offset). Thirty areas of 128GB is probably still enough swap for a 64GB 32-bit machine. Provide swp_to_radix_entry() and radix_to_swp_entry() conversions, and enforce filesize limit in read_swap_header(), just as for ptes. Signed-off-by:
Hugh Dickins <hughd@google.com> Acked-by:
Rik van Riel <riel@redhat.com> Signed-off-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org>
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Hugh Dickins authored
A patchset to extend tmpfs to MAX_LFS_FILESIZE by abandoning its peculiar swap vector, instead keeping a file's swap entries in the same radix tree as its struct page pointers: thus saving memory, and simplifying its code and locking. This patch: The radix_tree is used by several subsystems for different purposes. A major use is to store the struct page pointers of a file's pagecache for memory management. But what if mm wanted to store something other than page pointers there too? The low bit of a radix_tree entry is already used to denote an indirect pointer, for internal use, and the unlikely radix_tree_deref_retry() case. Define the next bit as denoting an exceptional entry, and supply inline functions radix_tree_exception() to return non-0 in either unlikely case, and radix_tree_exceptional_entry() to return non-0 in the second case. If a subsystem already uses radix_tree with that bit set, no problem: it does not affect internal workings at all, but is defined for the convenience of those storing well-aligned pointers in the radix_tree. The radix_tree_gang_lookups have an implicit assumption that the caller can deduce the offset of each entry returned e.g. by the page->index of a struct page. But that may not be feasible for some kinds of item to be stored there. radix_tree_gang_lookup_slot() allow for an optional indices argument, output array in which to return those offsets. The same could be added to other radix_tree_gang_lookups, but for now keep it to the only one for which we need it. Signed-off-by:
Hugh Dickins <hughd@google.com> Acked-by:
Rik van Riel <riel@redhat.com> Signed-off-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org>
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Andrew Morton authored
i386 allmodconfig: drivers/built-in.o: In function `aat2870_bl_remove': aat2870_bl.c:(.text+0x414f9): undefined reference to `backlight_device_unregister' drivers/built-in.o: In function `aat2870_bl_probe': aat2870_bl.c:(.text+0x418fc): undefined reference to `backlight_device_register' aat2870_bl.c:(.text+0x41a31): undefined reference to `backlight_device_unregiste Cc: Jin Park <jinyoungp@nvidia.com> Cc: Samuel Ortiz <sameo@linux.intel.com> Cc: Axel Lin <axel.lin@gmail.com> Cc: Richard Purdie <rpurdie@rpsys.net> Signed-off-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org>
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Axel Lin authored
- Current implementation tests wrong value for setting aat2870_bl->max_current. - In the current implementation, we cannot differentiate between 2 cases: a) if pdata->max_current is not set , or b) pdata->max_current is set to AAT2870_CURRENT_0_45 (which is also 0). Fix it by setting AAT2870_CURRENT_0_45 to be 1 and adjust the equation in aat2870_brightness() accordingly. Signed-off-by:
Axel Lin <axel.lin@gmail.com> Cc: Richard Purdie <rpurdie@rpsys.net> Cc: Samuel Ortiz <sameo@linux.intel.com> Tested-by:
Jin Park <jinyoungp@nvidia.com> Signed-off-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org>
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Axel Lin authored
backlight_device_register() returns ERR_PTR() on error. Signed-off-by:
Axel Lin <axel.lin@gmail.com> Cc: Richard Purdie <rpurdie@rpsys.net> Cc: Jin Park <jinyoungp@nvidia.com> Cc: Samuel Ortiz <sameo@linux.intel.com> Signed-off-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org>
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WANG Cong authored
Fix: arch/cris/arch-v10/kernel/irq.c:239: error: implicit declaration of function 'kgdb_init' arch/cris/arch-v10/kernel/irq.c:240: error: implicit declaration of function 'breakpoint' Declare these two functions. Reported-by:
Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by:
WANG Cong <xiyou.wangcong@gmail.com> Cc: Mikael Starvik <starvik@axis.com> Cc: Jesper Nilsson <jesper.nilsson@axis.com> Cc: <stable@kernel.org> Signed-off-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org>
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