From 195daf665a6299de98a4da3843fed2dd9de19d3a Mon Sep 17 00:00:00 2001 From: Ulrich Obergfell Date: Tue, 14 Apr 2015 15:44:13 -0700 Subject: watchdog: enable the new user interface of the watchdog mechanism With the current user interface of the watchdog mechanism it is only possible to disable or enable both lockup detectors at the same time. This series introduces new kernel parameters and changes the semantics of some existing kernel parameters, so that the hard lockup detector and the soft lockup detector can be disabled or enabled individually. With this series applied, the user interface is as follows. - parameters in /proc/sys/kernel . soft_watchdog This is a new parameter to control and examine the run state of the soft lockup detector. . nmi_watchdog The semantics of this parameter have changed. It can now be used to control and examine the run state of the hard lockup detector. . watchdog This parameter is still available to control the run state of both lockup detectors at the same time. If this parameter is examined, it shows the logical OR of soft_watchdog and nmi_watchdog. . watchdog_thresh The semantics of this parameter are not affected by the patch. - kernel command line parameters . nosoftlockup The semantics of this parameter have changed. It can now be used to disable the soft lockup detector at boot time. . nmi_watchdog=0 or nmi_watchdog=1 Disable or enable the hard lockup detector at boot time. The patch introduces '=1' as a new option. . nowatchdog The semantics of this parameter are not affected by the patch. It is still available to disable both lockup detectors at boot time. Also, remove the proc_dowatchdog() function which is no longer needed. [dzickus@redhat.com: wrote changelog] [dzickus@redhat.com: update documentation for kernel params and sysctl] Signed-off-by: Ulrich Obergfell Signed-off-by: Don Zickus Cc: Ingo Molnar Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Documentation/kernel-parameters.txt | 6 ++-- Documentation/sysctl/kernel.txt | 62 +++++++++++++++++++++++++++++++------ 2 files changed, 57 insertions(+), 11 deletions(-) (limited to 'Documentation') diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 01aa47d3b6ab..71eecb263250 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -2236,8 +2236,9 @@ bytes respectively. Such letter suffixes can also be entirely omitted. nmi_watchdog= [KNL,BUGS=X86] Debugging features for SMP kernels Format: [panic,][nopanic,][num] - Valid num: 0 + Valid num: 0 or 1 0 - turn nmi_watchdog off + 1 - turn nmi_watchdog on When panic is specified, panic when an NMI watchdog timeout occurs (or 'nopanic' to override the opposite default). @@ -2464,7 +2465,8 @@ bytes respectively. Such letter suffixes can also be entirely omitted. nousb [USB] Disable the USB subsystem - nowatchdog [KNL] Disable the lockup detector (NMI watchdog). + nowatchdog [KNL] Disable both lockup detectors, i.e. + soft-lockup and NMI watchdog (hard-lockup). nowb [ARM] diff --git a/Documentation/sysctl/kernel.txt b/Documentation/sysctl/kernel.txt index 83ab25660fc9..99d7eb3a1416 100644 --- a/Documentation/sysctl/kernel.txt +++ b/Documentation/sysctl/kernel.txt @@ -77,12 +77,14 @@ show up in /proc/sys/kernel: - shmmax [ sysv ipc ] - shmmni - softlockup_all_cpu_backtrace +- soft_watchdog - stop-a [ SPARC only ] - sysrq ==> Documentation/sysrq.txt - sysctl_writes_strict - tainted - threads-max - unknown_nmi_panic +- watchdog - watchdog_thresh - version @@ -417,16 +419,23 @@ successful IPC object allocation. nmi_watchdog: -Enables/Disables the NMI watchdog on x86 systems. When the value is -non-zero the NMI watchdog is enabled and will continuously test all -online cpus to determine whether or not they are still functioning -properly. Currently, passing "nmi_watchdog=" parameter at boot time is -required for this function to work. +This parameter can be used to control the NMI watchdog +(i.e. the hard lockup detector) on x86 systems. -If LAPIC NMI watchdog method is in use (nmi_watchdog=2 kernel -parameter), the NMI watchdog shares registers with oprofile. By -disabling the NMI watchdog, oprofile may have more registers to -utilize. + 0 - disable the hard lockup detector + 1 - enable the hard lockup detector + +The hard lockup detector monitors each CPU for its ability to respond to +timer interrupts. The mechanism utilizes CPU performance counter registers +that are programmed to generate Non-Maskable Interrupts (NMIs) periodically +while a CPU is busy. Hence, the alternative name 'NMI watchdog'. + +The NMI watchdog is disabled by default if the kernel is running as a guest +in a KVM virtual machine. This default can be overridden by adding + + nmi_watchdog=1 + +to the guest kernel command line (see Documentation/kernel-parameters.txt). ============================================================== @@ -816,6 +825,22 @@ NMI. ============================================================== +soft_watchdog + +This parameter can be used to control the soft lockup detector. + + 0 - disable the soft lockup detector + 1 - enable the soft lockup detector + +The soft lockup detector monitors CPUs for threads that are hogging the CPUs +without rescheduling voluntarily, and thus prevent the 'watchdog/N' threads +from running. The mechanism depends on the CPUs ability to respond to timer +interrupts which are needed for the 'watchdog/N' threads to be woken up by +the watchdog timer function, otherwise the NMI watchdog - if enabled - can +detect a hard lockup condition. + +============================================================== + tainted: Non-zero if the kernel has been tainted. Numeric values, which @@ -858,6 +883,25 @@ example. If a system hangs up, try pressing the NMI switch. ============================================================== +watchdog: + +This parameter can be used to disable or enable the soft lockup detector +_and_ the NMI watchdog (i.e. the hard lockup detector) at the same time. + + 0 - disable both lockup detectors + 1 - enable both lockup detectors + +The soft lockup detector and the NMI watchdog can also be disabled or +enabled individually, using the soft_watchdog and nmi_watchdog parameters. +If the watchdog parameter is read, for example by executing + + cat /proc/sys/kernel/watchdog + +the output of this command (0 or 1) shows the logical OR of soft_watchdog +and nmi_watchdog. + +============================================================== + watchdog_thresh: This value can be used to control the frequency of hrtimer and NMI -- cgit v1.2.3 From fc05f566210fa57f8e68ead8762b8dbb3f1c61e3 Mon Sep 17 00:00:00 2001 From: "Kirill A. Shutemov" Date: Tue, 14 Apr 2015 15:44:39 -0700 Subject: mm: rename __mlock_vma_pages_range() to populate_vma_page_range() __mlock_vma_pages_range() doesn't necessarily mlock pages. It depends on vma flags. The same codepath is used for MAP_POPULATE. Let's rename __mlock_vma_pages_range() to populate_vma_page_range(). This patch also drops mlock_vma_pages_range() references from documentation. It has gone in cea10a19b797 ("mm: directly use __mlock_vma_pages_range() in find_extend_vma()"). Signed-off-by: Kirill A. Shutemov Acked-by: Linus Torvalds Acked-by: David Rientjes Cc: Michel Lespinasse Cc: Rik van Riel Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Documentation/vm/unevictable-lru.txt | 26 ++++++++------------------ mm/internal.h | 2 +- mm/mlock.c | 12 ++++++------ mm/mmap.c | 4 ++-- 4 files changed, 17 insertions(+), 27 deletions(-) (limited to 'Documentation') diff --git a/Documentation/vm/unevictable-lru.txt b/Documentation/vm/unevictable-lru.txt index 744f82f86c58..86cb4624fc5a 100644 --- a/Documentation/vm/unevictable-lru.txt +++ b/Documentation/vm/unevictable-lru.txt @@ -317,7 +317,7 @@ If the VMA passes some filtering as described in "Filtering Special Vmas" below, mlock_fixup() will attempt to merge the VMA with its neighbors or split off a subset of the VMA if the range does not cover the entire VMA. Once the VMA has been merged or split or neither, mlock_fixup() will call -__mlock_vma_pages_range() to fault in the pages via get_user_pages() and to +populate_vma_page_range() to fault in the pages via get_user_pages() and to mark the pages as mlocked via mlock_vma_page(). Note that the VMA being mlocked might be mapped with PROT_NONE. In this case, @@ -327,7 +327,7 @@ fault path or in vmscan. Also note that a page returned by get_user_pages() could be truncated or migrated out from under us, while we're trying to mlock it. To detect this, -__mlock_vma_pages_range() checks page_mapping() after acquiring the page lock. +populate_vma_page_range() checks page_mapping() after acquiring the page lock. If the page is still associated with its mapping, we'll go ahead and call mlock_vma_page(). If the mapping is gone, we just unlock the page and move on. In the worst case, this will result in a page mapped in a VM_LOCKED VMA @@ -392,7 +392,7 @@ ignored for munlock. If the VMA is VM_LOCKED, mlock_fixup() again attempts to merge or split off the specified range. The range is then munlocked via the function -__mlock_vma_pages_range() - the same function used to mlock a VMA range - +populate_vma_page_range() - the same function used to mlock a VMA range - passing a flag to indicate that munlock() is being performed. Because the VMA access protections could have been changed to PROT_NONE after @@ -402,7 +402,7 @@ get_user_pages() was enhanced to accept a flag to ignore the permissions when fetching the pages - all of which should be resident as a result of previous mlocking. -For munlock(), __mlock_vma_pages_range() unlocks individual pages by calling +For munlock(), populate_vma_page_range() unlocks individual pages by calling munlock_vma_page(). munlock_vma_page() unconditionally clears the PG_mlocked flag using TestClearPageMlocked(). As with mlock_vma_page(), munlock_vma_page() use the Test*PageMlocked() function to handle the case where @@ -463,21 +463,11 @@ populate the page table. To mlock a range of memory under the unevictable/mlock infrastructure, the mmap() handler and task address space expansion functions call -mlock_vma_pages_range() specifying the vma and the address range to mlock. -mlock_vma_pages_range() filters VMAs like mlock_fixup(), as described above in -"Filtering Special VMAs". It will clear the VM_LOCKED flag, which will have -already been set by the caller, in filtered VMAs. Thus these VMA's need not be -visited for munlock when the region is unmapped. - -For "normal" VMAs, mlock_vma_pages_range() calls __mlock_vma_pages_range() to -fault/allocate the pages and mlock them. Again, like mlock_fixup(), -mlock_vma_pages_range() downgrades the mmap semaphore to read mode before -attempting to fault/allocate and mlock the pages and "upgrades" the semaphore -back to write mode before returning. - -The callers of mlock_vma_pages_range() will have already added the memory range +populate_vma_page_range() specifying the vma and the address range to mlock. + +The callers of populate_vma_page_range() will have already added the memory range to be mlocked to the task's "locked_vm". To account for filtered VMAs, -mlock_vma_pages_range() returns the number of pages NOT mlocked. All of the +populate_vma_page_range() returns the number of pages NOT mlocked. All of the callers then subtract a non-negative return value from the task's locked_vm. A negative return value represent an error - for example, from get_user_pages() attempting to fault in a VMA with PROT_NONE access. In this case, we leave the diff --git a/mm/internal.h b/mm/internal.h index a96da5b0029d..7df78a5269f3 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -240,7 +240,7 @@ void __vma_link_list(struct mm_struct *mm, struct vm_area_struct *vma, struct vm_area_struct *prev, struct rb_node *rb_parent); #ifdef CONFIG_MMU -extern long __mlock_vma_pages_range(struct vm_area_struct *vma, +extern long populate_vma_page_range(struct vm_area_struct *vma, unsigned long start, unsigned long end, int *nonblocking); extern void munlock_vma_pages_range(struct vm_area_struct *vma, unsigned long start, unsigned long end); diff --git a/mm/mlock.c b/mm/mlock.c index f756e28b33fc..9d0f3cd716c5 100644 --- a/mm/mlock.c +++ b/mm/mlock.c @@ -206,13 +206,13 @@ out: } /** - * __mlock_vma_pages_range() - mlock a range of pages in the vma. + * populate_vma_page_range() - populate a range of pages in the vma. * @vma: target vma * @start: start address * @end: end address * @nonblocking: * - * This takes care of making the pages present too. + * This takes care of mlocking the pages too if VM_LOCKED is set. * * return 0 on success, negative error code on error. * @@ -224,7 +224,7 @@ out: * If @nonblocking is non-NULL, it must held for read only and may be * released. If it's released, *@nonblocking will be set to 0. */ -long __mlock_vma_pages_range(struct vm_area_struct *vma, +long populate_vma_page_range(struct vm_area_struct *vma, unsigned long start, unsigned long end, int *nonblocking) { struct mm_struct *mm = vma->vm_mm; @@ -596,7 +596,7 @@ success: /* * vm_flags is protected by the mmap_sem held in write mode. * It's okay if try_to_unmap_one unmaps a page just after we - * set VM_LOCKED, __mlock_vma_pages_range will bring it back. + * set VM_LOCKED, populate_vma_page_range will bring it back. */ if (lock) @@ -702,11 +702,11 @@ int __mm_populate(unsigned long start, unsigned long len, int ignore_errors) if (nstart < vma->vm_start) nstart = vma->vm_start; /* - * Now fault in a range of pages. __mlock_vma_pages_range() + * Now fault in a range of pages. populate_vma_page_range() * double checks the vma flags, so that it won't mlock pages * if the vma was already munlocked. */ - ret = __mlock_vma_pages_range(vma, nstart, nend, &locked); + ret = populate_vma_page_range(vma, nstart, nend, &locked); if (ret < 0) { if (ignore_errors) { ret = 0; diff --git a/mm/mmap.c b/mm/mmap.c index 9ec50a368634..06a6076c92e5 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -2316,7 +2316,7 @@ find_extend_vma(struct mm_struct *mm, unsigned long addr) if (!prev || expand_stack(prev, addr)) return NULL; if (prev->vm_flags & VM_LOCKED) - __mlock_vma_pages_range(prev, addr, prev->vm_end, NULL); + populate_vma_page_range(prev, addr, prev->vm_end, NULL); return prev; } #else @@ -2351,7 +2351,7 @@ find_extend_vma(struct mm_struct *mm, unsigned long addr) if (expand_stack(vma, addr)) return NULL; if (vma->vm_flags & VM_LOCKED) - __mlock_vma_pages_range(vma, addr, start, NULL); + populate_vma_page_range(vma, addr, start, NULL); return vma; } #endif -- cgit v1.2.3 From 17e0db822b00cff96c1b662ac0dc0449cb70e0ec Mon Sep 17 00:00:00 2001 From: Sasha Levin Date: Tue, 14 Apr 2015 15:45:08 -0700 Subject: cma: debug: document new debugfs interface Document the structure and files under the new debugfs interface. Signed-off-by: Sasha Levin Cc: Joonsoo Kim Cc: Konrad Rzeszutek Wilk Cc: Laura Abbott Cc: Marek Szyprowski Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Documentation/cma/debugfs.txt | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+) create mode 100644 Documentation/cma/debugfs.txt (limited to 'Documentation') diff --git a/Documentation/cma/debugfs.txt b/Documentation/cma/debugfs.txt new file mode 100644 index 000000000000..6cef20a8cedc --- /dev/null +++ b/Documentation/cma/debugfs.txt @@ -0,0 +1,21 @@ +The CMA debugfs interface is useful to retrieve basic information out of the +different CMA areas and to test allocation/release in each of the areas. + +Each CMA zone represents a directory under /cma/, indexed by the +kernel's CMA index. So the first CMA zone would be: + + /cma/cma-0 + +The structure of the files created under that directory is as follows: + + - [RO] base_pfn: The base PFN (Page Frame Number) of the zone. + - [RO] count: Amount of memory in the CMA area. + - [RO] order_per_bit: Order of pages represented by one bit. + - [RO] bitmap: The bitmap of page states in the zone. + - [WO] alloc: Allocate N pages from that CMA area. For example: + + echo 5 > /cma/cma-2/alloc + +would try to allocate 5 pages from the cma-2 area. + + - [WO] free: Free N pages from that CMA area, similar to the above. -- cgit v1.2.3 From 53d85c98566535d7bc69470f008d7dcb09a0fec9 Mon Sep 17 00:00:00 2001 From: Vladimir Davydov Date: Tue, 14 Apr 2015 15:46:45 -0700 Subject: cleancache: forbid overriding cleancache_ops Currently, cleancache_register_ops returns the previous value of cleancache_ops to allow chaining. However, chaining, as it is implemented now, is extremely dangerous due to possible pool id collisions. Suppose, a new cleancache driver is registered after the previous one assigned an id to a super block. If the new driver assigns the same id to another super block, which is perfectly possible, we will have two different filesystems using the same id. No matter if the new driver implements chaining or not, we are likely to get data corruption with such a configuration eventually. This patch therefore disables the ability to override cleancache_ops altogether as potentially dangerous. If there is already cleancache driver registered, all further calls to cleancache_register_ops will return EBUSY. Since no user of cleancache implements chaining, we only need to make minor changes to the code outside the cleancache core. Signed-off-by: Vladimir Davydov Cc: Konrad Rzeszutek Wilk Cc: Boris Ostrovsky Cc: David Vrabel Cc: Mark Fasheh Cc: Joel Becker Cc: Stefan Hengelein Cc: Florian Schmaus Cc: Andor Daam Cc: Dan Magenheimer Cc: Bob Liu Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Documentation/vm/cleancache.txt | 4 +--- drivers/xen/tmem.c | 16 +++++++++------- include/linux/cleancache.h | 3 +-- mm/cleancache.c | 12 +++++++----- 4 files changed, 18 insertions(+), 17 deletions(-) (limited to 'Documentation') diff --git a/Documentation/vm/cleancache.txt b/Documentation/vm/cleancache.txt index 01d76282444e..e4b49df7a048 100644 --- a/Documentation/vm/cleancache.txt +++ b/Documentation/vm/cleancache.txt @@ -28,9 +28,7 @@ IMPLEMENTATION OVERVIEW A cleancache "backend" that provides transcendent memory registers itself to the kernel's cleancache "frontend" by calling cleancache_register_ops, passing a pointer to a cleancache_ops structure with funcs set appropriately. -Note that cleancache_register_ops returns the previous settings so that -chaining can be performed if desired. The functions provided must conform to -certain semantics as follows: +The functions provided must conform to certain semantics as follows: Most important, cleancache is "ephemeral". Pages which are copied into cleancache have an indefinite lifetime which is completely unknowable diff --git a/drivers/xen/tmem.c b/drivers/xen/tmem.c index 8a65423bc696..c4211a31612d 100644 --- a/drivers/xen/tmem.c +++ b/drivers/xen/tmem.c @@ -397,13 +397,15 @@ static int __init xen_tmem_init(void) #ifdef CONFIG_CLEANCACHE BUG_ON(sizeof(struct cleancache_filekey) != sizeof(struct tmem_oid)); if (tmem_enabled && cleancache) { - char *s = ""; - struct cleancache_ops *old_ops = - cleancache_register_ops(&tmem_cleancache_ops); - if (old_ops) - s = " (WARNING: cleancache_ops overridden)"; - pr_info("cleancache enabled, RAM provided by Xen Transcendent Memory%s\n", - s); + int err; + + err = cleancache_register_ops(&tmem_cleancache_ops); + if (err) + pr_warn("xen-tmem: failed to enable cleancache: %d\n", + err); + else + pr_info("cleancache enabled, RAM provided by " + "Xen Transcendent Memory\n"); } #endif #ifdef CONFIG_XEN_SELFBALLOONING diff --git a/include/linux/cleancache.h b/include/linux/cleancache.h index 29657d1c83fb..b23611f43cfb 100644 --- a/include/linux/cleancache.h +++ b/include/linux/cleancache.h @@ -33,8 +33,7 @@ struct cleancache_ops { void (*invalidate_fs)(int); }; -extern struct cleancache_ops * - cleancache_register_ops(struct cleancache_ops *ops); +extern int cleancache_register_ops(struct cleancache_ops *ops); extern void __cleancache_init_fs(struct super_block *); extern void __cleancache_init_shared_fs(struct super_block *); extern int __cleancache_get_page(struct page *); diff --git a/mm/cleancache.c b/mm/cleancache.c index 532495f2e4f4..aa10f9a3bc88 100644 --- a/mm/cleancache.c +++ b/mm/cleancache.c @@ -106,15 +106,17 @@ static DEFINE_MUTEX(poolid_mutex); */ /* - * Register operations for cleancache, returning previous thus allowing - * detection of multiple backends and possible nesting. + * Register operations for cleancache. Returns 0 on success. */ -struct cleancache_ops *cleancache_register_ops(struct cleancache_ops *ops) +int cleancache_register_ops(struct cleancache_ops *ops) { - struct cleancache_ops *old = cleancache_ops; int i; mutex_lock(&poolid_mutex); + if (cleancache_ops) { + mutex_unlock(&poolid_mutex); + return -EBUSY; + } for (i = 0; i < MAX_INITIALIZABLE_FS; i++) { if (fs_poolid_map[i] == FS_NO_BACKEND) fs_poolid_map[i] = ops->init_fs(PAGE_SIZE); @@ -130,7 +132,7 @@ struct cleancache_ops *cleancache_register_ops(struct cleancache_ops *ops) barrier(); cleancache_ops = ops; mutex_unlock(&poolid_mutex); - return old; + return 0; } EXPORT_SYMBOL(cleancache_register_ops); -- cgit v1.2.3 From 0ddab1d2ed664c85c95488eef569786a84aedf37 Mon Sep 17 00:00:00 2001 From: Toshi Kani Date: Tue, 14 Apr 2015 15:47:20 -0700 Subject: lib/ioremap.c: add huge I/O map capability interfaces Add ioremap_pud_enabled() and ioremap_pmd_enabled(), which return 1 when I/O mappings with pud/pmd are enabled on the kernel. ioremap_huge_init() calls arch_ioremap_pud_supported() and arch_ioremap_pmd_supported() to initialize the capabilities at boot-time. A new kernel option "nohugeiomap" is also added, so that user can disable the huge I/O map capabilities when necessary. Signed-off-by: Toshi Kani Cc: "H. Peter Anvin" Cc: Thomas Gleixner Cc: Ingo Molnar Cc: Arnd Bergmann Cc: Dave Hansen Cc: Robert Elliott Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Documentation/kernel-parameters.txt | 2 ++ arch/Kconfig | 3 +++ include/linux/io.h | 8 ++++++++ init/main.c | 2 ++ lib/ioremap.c | 37 +++++++++++++++++++++++++++++++++++++ 5 files changed, 52 insertions(+) (limited to 'Documentation') diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 71eecb263250..b1fa70907ccf 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -2323,6 +2323,8 @@ bytes respectively. Such letter suffixes can also be entirely omitted. register save and restore. The kernel will only save legacy floating-point registers on task switch. + nohugeiomap [KNL,x86] Disable kernel huge I/O mappings. + noxsave [BUGS=X86] Disables x86 extended register state save and restore using xsave. The kernel will fallback to enabling legacy floating-point and sse state. diff --git a/arch/Kconfig b/arch/Kconfig index a9c95d36ba70..c88c23f0a1da 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -446,6 +446,9 @@ config HAVE_IRQ_TIME_ACCOUNTING config HAVE_ARCH_TRANSPARENT_HUGEPAGE bool +config HAVE_ARCH_HUGE_VMAP + bool + config HAVE_ARCH_SOFT_DIRTY bool diff --git a/include/linux/io.h b/include/linux/io.h index fa02e55e5a2e..4cc299c598e0 100644 --- a/include/linux/io.h +++ b/include/linux/io.h @@ -38,6 +38,14 @@ static inline int ioremap_page_range(unsigned long addr, unsigned long end, } #endif +#ifdef CONFIG_HAVE_ARCH_HUGE_VMAP +void __init ioremap_huge_init(void); +int arch_ioremap_pud_supported(void); +int arch_ioremap_pmd_supported(void); +#else +static inline void ioremap_huge_init(void) { } +#endif + /* * Managed iomap interface */ diff --git a/init/main.c b/init/main.c index 4a6974e67839..f6dd8fe1f22c 100644 --- a/init/main.c +++ b/init/main.c @@ -80,6 +80,7 @@ #include #include #include +#include #include #include @@ -484,6 +485,7 @@ static void __init mm_init(void) percpu_init_late(); pgtable_init(); vmalloc_init(); + ioremap_huge_init(); } asmlinkage __visible void __init start_kernel(void) diff --git a/lib/ioremap.c b/lib/ioremap.c index 0c9216c48762..2008652c9a1f 100644 --- a/lib/ioremap.c +++ b/lib/ioremap.c @@ -13,6 +13,43 @@ #include #include +#ifdef CONFIG_HAVE_ARCH_HUGE_VMAP +int __read_mostly ioremap_pud_capable; +int __read_mostly ioremap_pmd_capable; +int __read_mostly ioremap_huge_disabled; + +static int __init set_nohugeiomap(char *str) +{ + ioremap_huge_disabled = 1; + return 0; +} +early_param("nohugeiomap", set_nohugeiomap); + +void __init ioremap_huge_init(void) +{ + if (!ioremap_huge_disabled) { + if (arch_ioremap_pud_supported()) + ioremap_pud_capable = 1; + if (arch_ioremap_pmd_supported()) + ioremap_pmd_capable = 1; + } +} + +static inline int ioremap_pud_enabled(void) +{ + return ioremap_pud_capable; +} + +static inline int ioremap_pmd_enabled(void) +{ + return ioremap_pmd_capable; +} + +#else /* !CONFIG_HAVE_ARCH_HUGE_VMAP */ +static inline int ioremap_pud_enabled(void) { return 0; } +static inline int ioremap_pmd_enabled(void) { return 0; } +#endif /* CONFIG_HAVE_ARCH_HUGE_VMAP */ + static int ioremap_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end, phys_addr_t phys_addr, pgprot_t prot) { -- cgit v1.2.3 From e4b0db72be2487bae0e3251c22f82c104f7c1cfd Mon Sep 17 00:00:00 2001 From: Vladimir Murzin Date: Tue, 14 Apr 2015 15:48:43 -0700 Subject: Documentation: update arch list in the 'memtest' entry Since arm64/arm support memtest command line option update the "memtest" entry. Signed-off-by: Vladimir Murzin Cc: "H. Peter Anvin" Cc: Catalin Marinas Cc: Ingo Molnar Cc: Mark Rutland Cc: Russell King Cc: Thomas Gleixner Cc: Will Deacon Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Documentation/kernel-parameters.txt | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'Documentation') diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index b1fa70907ccf..8cc635f4c4f0 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -1989,7 +1989,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted. seconds. Use this parameter to check at some other rate. 0 disables periodic checking. - memtest= [KNL,X86] Enable memtest + memtest= [KNL,X86,ARM] Enable memtest Format: default : 0 Specifies the number of memtest passes to be -- cgit v1.2.3