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2018-11-04sparc64: Fix regression in pmdp_invalidate().David S. Miller
[ Upstream commit cfb61b5e3e09f8b49bc4d685429df75f45127adc ] pmdp_invalidate() was changed to update the pmd atomically (to not lose dirty/access bits) and return the original pmd value. However, in doing so, we lost a lot of the essential work that set_pmd_at() does, namely to update hugepage mapping counts and queuing up the batched TLB flush entry. Thus we were not flushing entries out of the TLB when making such PMD changes. Fix this by abstracting the accounting work of set_pmd_at() out into a separate function, and call it from pmdp_establish(). Fixes: a8e654f01cb7 ("sparc64: update pmdp_invalidate() to return old pmd value") Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
2018-04-26sparc64: update pmdp_invalidate() to return old pmd valueNitin Gupta
[ Upstream commit a8e654f01cb725d0bfd741ebca1bf4c9337969cc ] It's required to avoid losing dirty and accessed bits. [akpm@linux-foundation.org: add a `do' to the do-while loop] Link: http://lkml.kernel.org/r/20171213105756.69879-9-kirill.shutemov@linux.intel.com Signed-off-by: Nitin Gupta <nitin.m.gupta@oracle.com> Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: David Miller <davem@davemloft.net> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Michal Hocko <mhocko@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-02License cleanup: add SPDX GPL-2.0 license identifier to files with no licenseGreg Kroah-Hartman
Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-06sparc64: Fix memory corruption when THP is enabledNitin Gupta
The memory corruption was happening due to incorrect TLB/TSB flushing of hugepages. Reported-by: David S. Miller <davem@davemloft.net> Signed-off-by: Nitin Gupta <nitin.m.gupta@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-23sparc64: Multi-page size supportNitin Gupta
Add support for using multiple hugepage sizes simultaneously on mainline. Currently, support for 256M has been added which can be used along with 8M pages. Page tables are set like this (e.g. for 256M page): VA + (8M * x) -> PA + (8M * x) (sz bit = 256M) where x in [0, 31] and TSB is set similarly: VA + (4M * x) -> PA + (4M * x) (sz bit = 256M) where x in [0, 63] - Testing Tested on Sonoma (which supports 256M pages) by running stream benchmark instances in parallel: one instance uses 8M pages and another uses 256M pages, consuming 48G each. Boot params used: default_hugepagesz=256M hugepagesz=256M hugepages=300 hugepagesz=8M hugepages=10000 Signed-off-by: Nitin Gupta <nitin.m.gupta@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-28sparc64 mm: Fix more TSB sizing issuesMike Kravetz
Commit af1b1a9b36b8 ("sparc64 mm: Fix base TSB sizing when hugetlb pages are used") addressed the difference between hugetlb and THP pages when computing TSB sizes. The following additional issues were also discovered while working with the code. In order to save memory, THP makes use of a huge zero page. This huge zero page does not count against a task's RSS, but it does consume TSB entries. This is similar to hugetlb pages. Therefore, count huge zero page entries in hugetlb_pte_count. Accounting of THP pages is done in the routine set_pmd_at(). Unfortunately, this does not catch the case where a THP page is split. To handle this case, decrement the count in pmdp_invalidate(). pmdp_invalidate is only called when splitting a THP. However, 'sanity checks' are added in case it is ever called for other purposes. A more general issue exists with HPAGE_SIZE accounting. hugetlb_pte_count tracks the number of HPAGE_SIZE (8M) pages. This value is used to size the TSB for HPAGE_SIZE pages. However, each HPAGE_SIZE page consists of two REAL_HPAGE_SIZE (4M) pages. The TSB contains an entry for each REAL_HPAGE_SIZE page. Therefore, the number of REAL_HPAGE_SIZE pages should be used to size the huge page TSB. A new compile time constant REAL_HPAGE_PER_HPAGE is used to multiply hugetlb_pte_count before sizing the TSB. Changes from V1 - Fixed build issue if hugetlb or THP not configured Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-07-28sparc64 mm: Fix base TSB sizing when hugetlb pages are usedMike Kravetz
do_sparc64_fault() calculates both the base and huge page RSS sizes and uses this information in calls to tsb_grow(). The calculation for base page TSB size is not correct if the task uses hugetlb pages. hugetlb pages are not accounted for in RSS, therefore the call to get_mm_rss(mm) does not include hugetlb pages. However, the number of pages based on huge_pte_count (which does include hugetlb pages) is subtracted from this value. This will result in an artificially small and often negative RSS calculation. The base TSB size is then often set to max_tsb_size as the passed RSS is unsigned, so a negative value looks really big. THP pages are also accounted for in huge_pte_count, and THP pages are accounted for in RSS so the calculation in do_sparc64_fault() is correct if a task only uses THP pages. A single huge_pte_count is not sufficient for TSB sizing if both hugetlb and THP pages can be used. Instead of a single counter, use two: one for hugetlb and one for THP. Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-05-20sparc64: Reduce TLB flushes during hugepte changesNitin Gupta
During hugepage map/unmap, TSB and TLB flushes are currently issued at every PAGE_SIZE'd boundary which is unnecessary. We now issue the flush at REAL_HPAGE_SIZE boundaries only. Without this patch workloads which unmap a large hugepage backed VMA region get CPU lockups due to excessive TLB flush calls. Orabug: 22365539, 22643230, 22995196 Signed-off-by: Nitin Gupta <nitin.m.gupta@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-26sparc: Replace __get_cpu_var usesChristoph Lameter
__get_cpu_var() is used for multiple purposes in the kernel source. One of them is address calculation via the form &__get_cpu_var(x). This calculates the address for the instance of the percpu variable of the current processor based on an offset. Other use cases are for storing and retrieving data from the current processors percpu area. __get_cpu_var() can be used as an lvalue when writing data or on the right side of an assignment. __get_cpu_var() is defined as : #define __get_cpu_var(var) (*this_cpu_ptr(&(var))) __get_cpu_var() always only does an address determination. However, store and retrieve operations could use a segment prefix (or global register on other platforms) to avoid the address calculation. this_cpu_write() and this_cpu_read() can directly take an offset into a percpu area and use optimized assembly code to read and write per cpu variables. This patch converts __get_cpu_var into either an explicit address calculation using this_cpu_ptr() or into a use of this_cpu operations that use the offset. Thereby address calculations are avoided and less registers are used when code is generated. At the end of the patch set all uses of __get_cpu_var have been removed so the macro is removed too. The patch set includes passes over all arches as well. Once these operations are used throughout then specialized macros can be defined in non -x86 arches as well in order to optimize per cpu access by f.e. using a global register that may be set to the per cpu base. Transformations done to __get_cpu_var() 1. Determine the address of the percpu instance of the current processor. DEFINE_PER_CPU(int, y); int *x = &__get_cpu_var(y); Converts to int *x = this_cpu_ptr(&y); 2. Same as #1 but this time an array structure is involved. DEFINE_PER_CPU(int, y[20]); int *x = __get_cpu_var(y); Converts to int *x = this_cpu_ptr(y); 3. Retrieve the content of the current processors instance of a per cpu variable. DEFINE_PER_CPU(int, y); int x = __get_cpu_var(y) Converts to int x = __this_cpu_read(y); 4. Retrieve the content of a percpu struct DEFINE_PER_CPU(struct mystruct, y); struct mystruct x = __get_cpu_var(y); Converts to memcpy(&x, this_cpu_ptr(&y), sizeof(x)); 5. Assignment to a per cpu variable DEFINE_PER_CPU(int, y) __get_cpu_var(y) = x; Converts to __this_cpu_write(y, x); 6. Increment/Decrement etc of a per cpu variable DEFINE_PER_CPU(int, y); __get_cpu_var(y)++ Converts to __this_cpu_inc(y) Cc: sparclinux@vger.kernel.org Acked-by: David S. Miller <davem@davemloft.net> Signed-off-by: Christoph Lameter <cl@linux.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2014-05-03sparc64: Fix huge PMD invalidation.David S. Miller
On sparc64 "present" and "valid" are seperate PTE bits, this allows us to naturally distinguish between the user explicitly asking for PROT_NONE with mprotect() and other situations. However we weren't handling this properly in the huge PMD paths. First of all, the page table walker in the TSB miss path only checks for _PAGE_PMD_HUGE. So the generic pmdp_invalidate() would clear _PAGE_PRESENT but the TLB miss paths would still load it into the TLB as a valid huge PMD. Fix this by clearing the valid bit in pmdp_invalidate(), and also checking the valid bit in USER_PGTABLE_CHECK_PMD_HUGE using "brgez" since _PAGE_VALID is bit 63 in both the sun4u and sun4v pte layouts. Signed-off-by: David S. Miller <davem@davemloft.net>
2014-05-03sparc64: Fix executable bit testing in set_pmd_at() paths.David S. Miller
This code was mistakenly using the exec bit from the PMD in all cases, even when the PMD isn't a huge PMD. If it's not a huge PMD, test the exec bit in the individual ptes down in tlb_batch_pmd_scan(). Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-28sparc: delete non-required instances of include <linux/init.h>Paul Gortmaker
None of these files are actually using any __init type directives and hence don't need to include <linux/init.h>. Most are just a left over from __devinit and __cpuinit removal, or simply due to code getting copied from one driver to the next. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-15Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-nextLinus Torvalds
Pull sparc update from David Miller: 1) Implement support for up to 47-bit physical addresses on sparc64. 2) Support HAVE_CONTEXT_TRACKING on sparc64, from Kirill Tkhai. 3) Fix Simba bridge window calculations, from Kjetil Oftedal. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-next: sparc64: Implement HAVE_CONTEXT_TRACKING sparc64: Add self-IPI support for smp_send_reschedule() sparc: PCI: Fix incorrect address calculation of PCI Bridge windows on Simba-bridges sparc64: Encode huge PMDs using PTE encoding. sparc64: Move to 64-bit PGDs and PMDs. sparc64: Move from 4MB to 8MB huge pages. sparc64: Make PAGE_OFFSET variable. sparc64: Fix inconsistent max-physical-address defines. sparc64: Document the shift counts used to validate linear kernel addresses. sparc64: Define PAGE_OFFSET in terms of physical address bits. sparc64: Use PAGE_OFFSET instead of a magic constant. sparc64: Clean up 64-bit mmap exclusion defines.
2013-11-15mm, thp: do not access mm->pmd_huge_pte directlyKirill A. Shutemov
Currently mm->pmd_huge_pte protected by page table lock. It will not work with split lock. We have to have per-pmd pmd_huge_pte for proper access serialization. For now, let's just introduce wrapper to access mm->pmd_huge_pte. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Tested-by: Alex Thorlton <athorlton@sgi.com> Cc: Alex Thorlton <athorlton@sgi.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: "Eric W . Biederman" <ebiederm@xmission.com> Cc: "Paul E . McKenney" <paulmck@linux.vnet.ibm.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andi Kleen <ak@linux.intel.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Dave Jones <davej@redhat.com> Cc: David Howells <dhowells@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Kees Cook <keescook@chromium.org> Cc: Mel Gorman <mgorman@suse.de> Cc: Michael Kerrisk <mtk.manpages@gmail.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Robin Holt <robinmholt@gmail.com> Cc: Sedat Dilek <sedat.dilek@gmail.com> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13sparc64: Encode huge PMDs using PTE encoding.David S. Miller
Now that we have 64-bits for PMDs we can stop using special encodings for the huge PMD values, and just put real PTEs in there. We allocate a _PAGE_PMD_HUGE bit to distinguish between plain PMDs and huge ones. It is the same for both 4U and 4V PTE layouts. We also use _PAGE_SPECIAL to indicate the splitting state, since a huge PMD cannot also be special. All of the PMD --> PTE translation code disappears, and most of the huge PMD bit modifications and tests just degenerate into the PTE operations. In particular USER_PGTABLE_CHECK_PMD_HUGE becomes trivial. As a side effect, normal PMDs don't shift the physical address around. This also speeds up the page table walks in the TLB miss paths since they don't have to do the shifts any more. Another non-trivial aspect is that pte_modify() has to be changed to preserve the _PAGE_PMD_HUGE bits as well as the page size field of the pte. Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-12sparc64: Move from 4MB to 8MB huge pages.David S. Miller
The impetus for this is that we would like to move to 64-bit PMDs and PGDs, but that would result in only supporting a 42-bit address space with the current page table layout. It'd be nice to support at least 43-bits. The reason we'd end up with only 42-bits after making PMDs and PGDs 64-bit is that we only use half-page sized PTE tables in order to make PMDs line up to 4MB, the hardware huge page size we use. So what we do here is we make huge pages 8MB, and fabricate them using 4MB hw TLB entries. Facilitate this by providing a "REAL_HPAGE_SHIFT" which is used in places that really need to operate on hardware 4MB pages. Use full pages (512 entries) for PTE tables, and adjust PMD_SHIFT, PGD_SHIFT, and the build time CPP test as needed. Use a CPP test to make sure REAL_HPAGE_SHIFT and the _PAGE_SZHUGE_* we use match up. This makes the pgtable cache completely unused, so remove the code managing it and the state used in mm_context_t. Now we have less spinlocks taken in the page table allocation path. The technique we use to fabricate the 8MB pages is to transfer bit 22 from the missing virtual address into the PTEs physical address field. That takes care of the transparent huge pages case. For hugetlb, we fill things in at the PTE level and that code already puts the sub huge page physical bits into the PTEs, based upon the offset, so there is nothing special we need to do. It all just works out. So, a small amount of complexity in the THP case, but this code is about to get much simpler when we move the 64-bit PMDs as we can move away from the fancy 32-bit huge PMD encoding and just put a real PTE value in there. With bug fixes and help from Bob Picco. Signed-off-by: David S. Miller <davem@davemloft.net>
2013-07-01Merge tag 'v3.10' into nextBenjamin Herrenschmidt
Merge 3.10 in order to get some of the last minute powerpc changes, resolve conflicts and add additional fixes on top of them.
2013-06-20mm/THP: add pmd args to pgtable deposit and withdraw APIsAneesh Kumar K.V
This will be later used by powerpc THP support. In powerpc we want to use pgtable for storing the hash index values. So instead of adding them to mm_context list, we would like to store them in the second half of pmd Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Reviewed-by: Andrea Arcangeli <aarcange@redhat.com> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-06-19sparc: tsb must be flushed before tlbDave Kleikamp
This fixes a race where a cpu may re-load a tlb from a stale tsb right after it has been flushed by a remote function call. I still see some instability when stressing the system with parallel kernel builds while creating memory pressure by writing to /proc/sys/vm/nr_hugepages, but this patch improves the stability significantly. Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com> Acked-by: Bob Picco <bob.picco@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-04-24sparc64: Fix missing put_cpu_var() in tlb_batch_add_one() when not batching.David S. Miller
Reported-by: Meelis Roos <mroos@linux.ee> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-04-19sparc64: Fix race in TLB batch processing.David S. Miller
As reported by Dave Kleikamp, when we emit cross calls to do batched TLB flush processing we have a race because we do not synchronize on the sibling cpus completing the cross call. So meanwhile the TLB batch can be reset (tb->tlb_nr set to zero, etc.) and either flushes are missed or flushes will flush the wrong addresses. Fix this by using generic infrastructure to synchonize on the completion of the cross call. This first required getting the flush_tlb_pending() call out from switch_to() which operates with locks held and interrupts disabled. The problem is that smp_call_function_many() cannot be invoked with IRQs disabled and this is explicitly checked for with WARN_ON_ONCE(). We get the batch processing outside of locked IRQ disabled sections by using some ideas from the powerpc port. Namely, we only batch inside of arch_{enter,leave}_lazy_mmu_mode() calls. If we're not in such a region, we flush TLBs synchronously. 1) Get rid of xcall_flush_tlb_pending and per-cpu type implementations. 2) Do TLB batch cross calls instead via: smp_call_function_many() tlb_pending_func() __flush_tlb_pending() 3) Batch only in lazy mmu sequences: a) Add 'active' member to struct tlb_batch b) Define __HAVE_ARCH_ENTER_LAZY_MMU_MODE c) Set 'active' in arch_enter_lazy_mmu_mode() d) Run batch and clear 'active' in arch_leave_lazy_mmu_mode() e) Check 'active' in tlb_batch_add_one() and do a synchronous flush if it's clear. 4) Add infrastructure for synchronous TLB page flushes. a) Implement __flush_tlb_page and per-cpu variants, patch as needed. b) Likewise for xcall_flush_tlb_page. c) Implement smp_flush_tlb_page() to invoke the cross-call. d) Wire up global_flush_tlb_page() to the right routine based upon CONFIG_SMP 5) It turns out that singleton batches are very common, 2 out of every 3 batch flushes have only a single entry in them. The batch flush waiting is very expensive, both because of the poll on sibling cpu completeion, as well as because passing the tlb batch pointer to the sibling cpus invokes a shared memory dereference. Therefore, in flush_tlb_pending(), if there is only one entry in the batch perform a completely asynchronous global_flush_tlb_page() instead. Reported-by: Dave Kleikamp <dave.kleikamp@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net> Acked-by: Dave Kleikamp <dave.kleikamp@oracle.com>
2013-02-20sparc64: Fix tsb_grow() in atomic context.David S. Miller
If our first THP installation for an MM is via the set_pmd_at() done during khugepaged's collapsing we'll end up in tsb_grow() trying to do a GFP_KERNEL allocation with several locks held. Simply using GFP_ATOMIC in this situation is not the best option because we really can't have this fail, so we'd really like to keep this an order 0 GFP_KERNEL allocation if possible. Also, doing the TSB allocation from khugepaged is a really bad idea because we'll allocate it potentially from the wrong NUMA node in that context. So what we do is defer the hugepage TSB allocation until the first TLB miss we take on a hugepage. This is slightly tricky because we have to handle two unusual cases: 1) Taking the first hugepage TLB miss in the window trap handler. We'll call the winfix_trampoline when that is detected. 2) An initial TSB allocation via TLB miss races with a hugetlb fault on another cpu running the same MM. We handle this by unconditionally loading the TSB we see into the current cpu even if it's non-NULL at hugetlb_setup time. Reported-by: Meelis Roos <mroos@ut.ee> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-10-09sparc64: Support transparent huge pages.David Miller
This is relatively easy since PMD's now cover exactly 4MB of memory. Our PMD entries are 32-bits each, so we use a special encoding. The lowest bit, PMD_ISHUGE, determines the interpretation. This is possible because sparc64's page tables are purely software entities so we can use whatever encoding scheme we want. We just have to make the TLB miss assembler page table walkers aware of the layout. set_pmd_at() works much like set_pte_at() but it has to operate in two page from a table of non-huge PTEs, so we have to queue up TLB flushes based upon what mappings are valid in the PTE table. In the second regime we are going from huge-page to non-huge-page, and in that case we need only queue up a single TLB flush to push out the huge page mapping. We still have 5 bits remaining in the huge PMD encoding so we can very likely support any new pieces of THP state tracking that might get added in the future. With lots of help from Johannes Weiner. Signed-off-by: David S. Miller <davem@davemloft.net> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Gerald Schaefer <gerald.schaefer@de.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-05-25sparc: mmu_gather reworkPeter Zijlstra
Rework the sparc mmu_gather usage to conform to the new world order :-) Sparc mmu_gather does two things: - tracks vaddrs to unhash - tracks pages to free Split these two things like powerpc has done and keep the vaddrs in per-cpu data structures and flush them on context switch. The remaining bits can then use the generic mmu_gather. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: David Miller <davem@davemloft.net> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Jeff Dike <jdike@addtoit.com> Cc: Richard Weinberger <richard@nod.at> Cc: Tony Luck <tony.luck@intel.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Hugh Dickins <hughd@google.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Nick Piggin <npiggin@kernel.dk> Cc: Namhyung Kim <namhyung@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-12-04sparc,sparc64: unify mm/Sam Ravnborg
- move all sparc64/mm/ files to arch/sparc/mm/ - commonly named files are named _64.c - add files to sparc/mm/Makefile preserving link order - delete now unused sparc64/mm/Makefile - sparc64 now finds mm/ in sparc Signed-off-by: Sam Ravnborg <sam@ravnborg.org> Signed-off-by: David S. Miller <davem@davemloft.net>