user/sven/linux.git/include/linux/memblock.h, branch leds/HEAD

memblock: introduce a for_each_reserved_mem_region iterator

2015-07-01T02:44:55Z

Struct page initialisation had been identified as one of the reasons why large machines take a long time to boot. Patches were posted a long time ago to defer initialisation until they were first used. This was rejected on the grounds it should not be necessary to hurt the fast paths. This series reuses much of the work from that time but defers the initialisation of memory to kswapd so that one thread per node initialises memory local to that node. After applying the series and setting the appropriate Kconfig variable I see this in the boot log on a 64G machine [ 7.383764] kswapd 0 initialised deferred memory in 188ms [ 7.404253] kswapd 1 initialised deferred memory in 208ms [ 7.411044] kswapd 3 initialised deferred memory in 216ms [ 7.411551] kswapd 2 initialised deferred memory in 216ms On a 1TB machine, I see [ 8.406511] kswapd 3 initialised deferred memory in 1116ms [ 8.428518] kswapd 1 initialised deferred memory in 1140ms [ 8.435977] kswapd 0 initialised deferred memory in 1148ms [ 8.437416] kswapd 2 initialised deferred memory in 1148ms Once booted the machine appears to work as normal. Boot times were measured from the time shutdown was called until ssh was available again. In the 64G case, the boot time savings are negligible. On the 1TB machine, the savings were 16 seconds. Nate Zimmer said: : On an older 8 TB box with lots and lots of cpus the boot time, as : measure from grub to login prompt, the boot time improved from 1484 : seconds to exactly 1000 seconds. Waiman Long said: : I ran a bootup timing test on a 12-TB 16-socket IvyBridge-EX system. From : grub menu to ssh login, the bootup time was 453s before the patch and 265s : after the patch - a saving of 188s (42%). Daniel Blueman said: : On a 7TB, 1728-core NumaConnect system with 108 NUMA nodes, we're seeing : stock 4.0 boot in 7136s. This drops to 2159s, or a 70% reduction with : this patchset. Non-temporal PMD init (https://lkml.org/lkml/2015/4/23/350) : drops this to 1045s. This patch (of 13): As part of initializing struct page's in 2MiB chunks, we noticed that at the end of free_all_bootmem(), there was nothing which had forced the reserved/allocated 4KiB pages to be initialized. This helper function will be used for that expansion. Signed-off-by: Robin Holt Signed-off-by: Nate Zimmer Signed-off-by: Mel Gorman Tested-by: Nate Zimmer Tested-by: Waiman Long Tested-by: Daniel J Blueman Acked-by: Pekka Enberg Cc: Robin Holt Cc: Dave Hansen Cc: Waiman Long Cc: Scott Norton Cc: "Luck, Tony" Cc: Ingo Molnar Cc: "H. Peter Anvin" Cc: Thomas Gleixner Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm/memblock: allocate boot time data structures from mirrored memory

2015-06-25T00:49:45Z

Try to allocate all boot time kernel data structures from mirrored memory. If we run out of mirrored memory print warnings, but fall back to using non-mirrored memory to make sure that we still boot. By number of bytes, most of what we allocate at boot time is the page structures. 64 bytes per 4K page on x86_64 ... or about 1.5% of total system memory. For workloads where the bulk of memory is allocated to applications this may represent a useful improvement to system availability since 1.5% of total memory might be a third of the memory allocated to the kernel. Signed-off-by: Tony Luck Cc: Xishi Qiu Cc: Hanjun Guo Cc: Xiexiuqi Cc: Ingo Molnar Cc: Thomas Gleixner Cc: "H. Peter Anvin" Cc: Yinghai Lu Cc: Naoya Horiguchi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm/memblock: add extra "flags" to memblock to allow selection of memory based on attribute

2015-06-25T00:49:44Z

Some high end Intel Xeon systems report uncorrectable memory errors as a recoverable machine check. Linux has included code for some time to process these and just signal the affected processes (or even recover completely if the error was in a read only page that can be replaced by reading from disk). But we have no recovery path for errors encountered during kernel code execution. Except for some very specific cases were are unlikely to ever be able to recover. Enter memory mirroring. Actually 3rd generation of memory mirroing. Gen1: All memory is mirrored Pro: No s/w enabling - h/w just gets good data from other side of the mirror Con: Halves effective memory capacity available to OS/applications Gen2: Partial memory mirror - just mirror memory begind some memory controllers Pro: Keep more of the capacity Con: Nightmare to enable. Have to choose between allocating from mirrored memory for safety vs. NUMA local memory for performance Gen3: Address range partial memory mirror - some mirror on each memory controller Pro: Can tune the amount of mirror and keep NUMA performance Con: I have to write memory management code to implement The current plan is just to use mirrored memory for kernel allocations. This has been broken into two phases: 1) This patch series - find the mirrored memory, use it for boot time allocations 2) Wade into mm/page_alloc.c and define a ZONE_MIRROR to pick up the unused mirrored memory from mm/memblock.c and only give it out to select kernel allocations (this is still being scoped because page_alloc.c is scary). This patch (of 3): Add extra "flags" to memblock to allow selection of memory based on attribute. No functional changes Signed-off-by: Tony Luck Cc: Xishi Qiu Cc: Hanjun Guo Cc: Xiexiuqi Cc: Ingo Molnar Cc: Thomas Gleixner Cc: "H. Peter Anvin" Cc: Yinghai Lu Cc: Naoya Horiguchi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

memtest: use phys_addr_t for physical addresses

2015-04-14T23:49:06Z

Since memtest might be used by other architectures pass input parameters as phys_addr_t instead of long to prevent overflow. Signed-off-by: Vladimir Murzin Acked-by: Will Deacon Tested-by: Mark Rutland Cc: "H. Peter Anvin" Cc: Catalin Marinas Cc: Ingo Molnar Cc: Russell King Cc: Thomas Gleixner Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm: move memtest under mm

2015-04-14T23:49:06Z

Memtest is a simple feature which fills the memory with a given set of patterns and validates memory contents, if bad memory regions is detected it reserves them via memblock API. Since memblock API is widely used by other architectures this feature can be enabled outside of x86 world. This patch set promotes memtest to live under generic mm umbrella and enables memtest feature for arm/arm64. It was reported that this patch set was useful for tracking down an issue with some errant DMA on an arm64 platform. This patch (of 6): There is nothing platform dependent in the core memtest code, so other platforms might benefit from this feature too. [linux@roeck-us.net: MEMTEST depends on MEMBLOCK] Signed-off-by: Vladimir Murzin Acked-by: Will Deacon Tested-by: Mark Rutland Cc: Ingo Molnar Cc: Thomas Gleixner Cc: "H. Peter Anvin" Cc: Catalin Marinas Cc: Russell King Cc: Paul Bolle Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

include/linux/memblock.h: add __init to memblock_set_bottom_up()

2014-08-07T01:01:15Z

memblock_set_bottom_up() is only called by __init cmdline_parse_movable_node() and __init numa_init(). Signed-off-by: Fabian Frederick Reviewed-by: Tang Chen Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

memblock: introduce memblock_alloc_range()

2014-06-04T23:53:57Z

This introduces memblock_alloc_range() which allocates memblock from the specified range of physical address. I would like to use this function to specify the location of CMA. Signed-off-by: Akinobu Mita Cc: Marek Szyprowski Cc: Konrad Rzeszutek Wilk Cc: David Woodhouse Cc: Don Dutile Cc: Thomas Gleixner Cc: Ingo Molnar Cc: "H. Peter Anvin" Cc: Andi Kleen Cc: Yinghai Lu Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm/memblock: add physical memory list

2014-05-20T06:58:39Z

Add the physmem list to the memblock structure. This list only exists if HAVE_MEMBLOCK_PHYS_MAP is selected and contains the unmodified list of physically available memory. It differs from the memblock memory list as it always contains all memory ranges even if the memory has been restricted, e.g. by use of the mem= kernel parameter. Signed-off-by: Philipp Hachtmann Signed-off-by: Martin Schwidefsky

mm/memblock: Do some refactoring, enhance API

2014-05-20T06:58:39Z

Refactor the memblock code and extend the memblock API to make it more flexible. With the extended API it is simple to define and work with additional memory lists. The static functions memblock_add_region and __memblock_remove are renamed to memblock_add_range and meblock_remove_range and added to the memblock API. The __next_free_mem_range and __next_free_mem_range_rev functions are replaced with calls to the more generic list walkers __next_mem_range and __next_mem_range_rev. To walk an arbitrary memory list two new macros for_each_mem_range and for_each_mem_range_rev are added. These new macros are used to define for_each_free_mem_range and for_each_free_mem_range_reverse. Signed-off-by: Philipp Hachtmann Signed-off-by: Martin Schwidefsky

ARM: 7993/1: mm/memblock: add memblock_get_current_limit

2014-03-12T00:16:56Z

Apart from setting the limit of memblock, it's also useful to be able to get the limit to avoid recalculating it every time. Add the function to do so. Acked-by: Catalin Marinas Acked-by: Santosh Shilimkar Acked-by: Andrew Morton Acked-by: Nicolas Pitre Signed-off-by: Laura Abbott Signed-off-by: Russell King