| Author | Tokens | Token Proportion | Commits | Commit Proportion |
|---|---|---|---|---|
| Jeremy Fitzhardinge | 775 | 32.12% | 5 | 8.62% |
| David Vrabel | 613 | 25.40% | 11 | 18.97% |
| Daniel Kiper | 387 | 16.04% | 6 | 10.34% |
| Konrad Rzeszutek Wilk | 154 | 6.38% | 2 | 3.45% |
| Ross Lagerwall | 91 | 3.77% | 3 | 5.17% |
| Juergen Gross | 79 | 3.27% | 4 | 6.90% |
| Julien Grall | 66 | 2.74% | 2 | 3.45% |
| Arun K S | 65 | 2.69% | 1 | 1.72% |
| Vitaly Kuznetsov | 43 | 1.78% | 2 | 3.45% |
| David Hildenbrand | 37 | 1.53% | 3 | 5.17% |
| Boris Ostrovsky | 21 | 0.87% | 3 | 5.17% |
| Oleksandr Andrushchenko | 18 | 0.75% | 1 | 1.72% |
| Wei Liu | 15 | 0.62% | 2 | 3.45% |
| Jie Liu | 10 | 0.41% | 1 | 1.72% |
| Stefano Stabellini | 9 | 0.37% | 3 | 5.17% |
| Joe Perches | 8 | 0.33% | 1 | 1.72% |
| Daniel De Graaf | 7 | 0.29% | 1 | 1.72% |
| Lisa Nguyen | 4 | 0.17% | 1 | 1.72% |
| Tejun Heo | 3 | 0.12% | 1 | 1.72% |
| Ian Campbell | 3 | 0.12% | 2 | 3.45% |
| Ingo Molnar | 3 | 0.12% | 1 | 1.72% |
| Mike Rapoport | 1 | 0.04% | 1 | 1.72% |
| Toshi Kani | 1 | 0.04% | 1 | 1.72% |
| Total | 2413 | 58 |
/****************************************************************************** * Xen balloon driver - enables returning/claiming memory to/from Xen. * * Copyright (c) 2003, B Dragovic * Copyright (c) 2003-2004, M Williamson, K Fraser * Copyright (c) 2005 Dan M. Smith, IBM Corporation * Copyright (c) 2010 Daniel Kiper * * Memory hotplug support was written by Daniel Kiper. Work on * it was sponsored by Google under Google Summer of Code 2010 * program. Jeremy Fitzhardinge from Citrix was the mentor for * this project. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License version 2 * as published by the Free Software Foundation; or, when distributed * separately from the Linux kernel or incorporated into other * software packages, subject to the following license: * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this source file (the "Software"), to deal in the Software without * restriction, including without limitation the rights to use, copy, modify, * merge, publish, distribute, sublicense, and/or sell copies of the Software, * and to permit persons to whom the Software is furnished to do so, subject to * the following conditions: * * The above copyright notice and this permission notice shall be included in * all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS * IN THE SOFTWARE. */ #define pr_fmt(fmt) "xen:" KBUILD_MODNAME ": " fmt #include <linux/cpu.h> #include <linux/kernel.h> #include <linux/sched.h> #include <linux/cred.h> #include <linux/errno.h> #include <linux/mm.h> #include <linux/memblock.h> #include <linux/pagemap.h> #include <linux/highmem.h> #include <linux/mutex.h> #include <linux/list.h> #include <linux/gfp.h> #include <linux/notifier.h> #include <linux/memory.h> #include <linux/memory_hotplug.h> #include <linux/percpu-defs.h> #include <linux/slab.h> #include <linux/sysctl.h> #include <asm/page.h> #include <asm/pgalloc.h> #include <asm/pgtable.h> #include <asm/tlb.h> #include <asm/xen/hypervisor.h> #include <asm/xen/hypercall.h> #include <xen/xen.h> #include <xen/interface/xen.h> #include <xen/interface/memory.h> #include <xen/balloon.h> #include <xen/features.h> #include <xen/page.h> #include <xen/mem-reservation.h> static int xen_hotplug_unpopulated; #ifdef CONFIG_XEN_BALLOON_MEMORY_HOTPLUG static int zero; static int one = 1; static struct ctl_table balloon_table[] = { { .procname = "hotplug_unpopulated", .data = &xen_hotplug_unpopulated, .maxlen = sizeof(int), .mode = 0644, .proc_handler = proc_dointvec_minmax, .extra1 = &zero, .extra2 = &one, }, { } }; static struct ctl_table balloon_root[] = { { .procname = "balloon", .mode = 0555, .child = balloon_table, }, { } }; static struct ctl_table xen_root[] = { { .procname = "xen", .mode = 0555, .child = balloon_root, }, { } }; #endif /* * Use one extent per PAGE_SIZE to avoid to break down the page into * multiple frame. */ #define EXTENT_ORDER (fls(XEN_PFN_PER_PAGE) - 1) /* * balloon_process() state: * * BP_DONE: done or nothing to do, * BP_WAIT: wait to be rescheduled, * BP_EAGAIN: error, go to sleep, * BP_ECANCELED: error, balloon operation canceled. */ enum bp_state { BP_DONE, BP_WAIT, BP_EAGAIN, BP_ECANCELED }; static DEFINE_MUTEX(balloon_mutex); struct balloon_stats balloon_stats; EXPORT_SYMBOL_GPL(balloon_stats); /* We increase/decrease in batches which fit in a page */ static xen_pfn_t frame_list[PAGE_SIZE / sizeof(xen_pfn_t)]; /* List of ballooned pages, threaded through the mem_map array. */ static LIST_HEAD(ballooned_pages); static DECLARE_WAIT_QUEUE_HEAD(balloon_wq); /* Main work function, always executed in process context. */ static void balloon_process(struct work_struct *work); static DECLARE_DELAYED_WORK(balloon_worker, balloon_process); /* When ballooning out (allocating memory to return to Xen) we don't really want the kernel to try too hard since that can trigger the oom killer. */ #define GFP_BALLOON \ (GFP_HIGHUSER | __GFP_NOWARN | __GFP_NORETRY | __GFP_NOMEMALLOC) /* balloon_append: add the given page to the balloon. */ static void __balloon_append(struct page *page) { /* Lowmem is re-populated first, so highmem pages go at list tail. */ if (PageHighMem(page)) { list_add_tail(&page->lru, &ballooned_pages); balloon_stats.balloon_high++; } else { list_add(&page->lru, &ballooned_pages); balloon_stats.balloon_low++; } wake_up(&balloon_wq); } static void balloon_append(struct page *page) { __balloon_append(page); } /* balloon_retrieve: rescue a page from the balloon, if it is not empty. */ static struct page *balloon_retrieve(bool require_lowmem) { struct page *page; if (list_empty(&ballooned_pages)) return NULL; page = list_entry(ballooned_pages.next, struct page, lru); if (require_lowmem && PageHighMem(page)) return NULL; list_del(&page->lru); if (PageHighMem(page)) balloon_stats.balloon_high--; else balloon_stats.balloon_low--; return page; } static struct page *balloon_next_page(struct page *page) { struct list_head *next = page->lru.next; if (next == &ballooned_pages) return NULL; return list_entry(next, struct page, lru); } static enum bp_state update_schedule(enum bp_state state) { if (state == BP_WAIT) return BP_WAIT; if (state == BP_ECANCELED) return BP_ECANCELED; if (state == BP_DONE) { balloon_stats.schedule_delay = 1; balloon_stats.retry_count = 1; return BP_DONE; } ++balloon_stats.retry_count; if (balloon_stats.max_retry_count != RETRY_UNLIMITED && balloon_stats.retry_count > balloon_stats.max_retry_count) { balloon_stats.schedule_delay = 1; balloon_stats.retry_count = 1; return BP_ECANCELED; } balloon_stats.schedule_delay <<= 1; if (balloon_stats.schedule_delay > balloon_stats.max_schedule_delay) balloon_stats.schedule_delay = balloon_stats.max_schedule_delay; return BP_EAGAIN; } #ifdef CONFIG_XEN_BALLOON_MEMORY_HOTPLUG static void release_memory_resource(struct resource *resource) { if (!resource) return; /* * No need to reset region to identity mapped since we now * know that no I/O can be in this region */ release_resource(resource); kfree(resource); } static struct resource *additional_memory_resource(phys_addr_t size) { struct resource *res; int ret; res = kzalloc(sizeof(*res), GFP_KERNEL); if (!res) return NULL; res->name = "System RAM"; res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY; ret = allocate_resource(&iomem_resource, res, size, 0, -1, PAGES_PER_SECTION * PAGE_SIZE, NULL, NULL); if (ret < 0) { pr_err("Cannot allocate new System RAM resource\n"); kfree(res); return NULL; } #ifdef CONFIG_SPARSEMEM { unsigned long limit = 1UL << (MAX_PHYSMEM_BITS - PAGE_SHIFT); unsigned long pfn = res->start >> PAGE_SHIFT; if (pfn > limit) { pr_err("New System RAM resource outside addressable RAM (%lu > %lu)\n", pfn, limit); release_memory_resource(res); return NULL; } } #endif return res; } static enum bp_state reserve_additional_memory(void) { long credit; struct resource *resource; int nid, rc; unsigned long balloon_hotplug; credit = balloon_stats.target_pages + balloon_stats.target_unpopulated - balloon_stats.total_pages; /* * Already hotplugged enough pages? Wait for them to be * onlined. */ if (credit <= 0) return BP_WAIT; balloon_hotplug = round_up(credit, PAGES_PER_SECTION); resource = additional_memory_resource(balloon_hotplug * PAGE_SIZE); if (!resource) goto err; nid = memory_add_physaddr_to_nid(resource->start); #ifdef CONFIG_XEN_HAVE_PVMMU /* * We don't support PV MMU when Linux and Xen is using * different page granularity. */ BUILD_BUG_ON(XEN_PAGE_SIZE != PAGE_SIZE); /* * add_memory() will build page tables for the new memory so * the p2m must contain invalid entries so the correct * non-present PTEs will be written. * * If a failure occurs, the original (identity) p2m entries * are not restored since this region is now known not to * conflict with any devices. */ if (!xen_feature(XENFEAT_auto_translated_physmap)) { unsigned long pfn, i; pfn = PFN_DOWN(resource->start); for (i = 0; i < balloon_hotplug; i++) { if (!set_phys_to_machine(pfn + i, INVALID_P2M_ENTRY)) { pr_warn("set_phys_to_machine() failed, no memory added\n"); goto err; } } } #endif /* * add_memory_resource() will call online_pages() which in its turn * will call xen_online_page() callback causing deadlock if we don't * release balloon_mutex here. Unlocking here is safe because the * callers drop the mutex before trying again. */ mutex_unlock(&balloon_mutex); /* add_memory_resource() requires the device_hotplug lock */ lock_device_hotplug(); rc = add_memory_resource(nid, resource); unlock_device_hotplug(); mutex_lock(&balloon_mutex); if (rc) { pr_warn("Cannot add additional memory (%i)\n", rc); goto err; } balloon_stats.total_pages += balloon_hotplug; return BP_WAIT; err: release_memory_resource(resource); return BP_ECANCELED; } static void xen_online_page(struct page *page, unsigned int order) { unsigned long i, size = (1 << order); unsigned long start_pfn = page_to_pfn(page); struct page *p; pr_debug("Online %lu pages starting at pfn 0x%lx\n", size, start_pfn); mutex_lock(&balloon_mutex); for (i = 0; i < size; i++) { p = pfn_to_page(start_pfn + i); __online_page_set_limits(p); __SetPageOffline(p); __balloon_append(p); } mutex_unlock(&balloon_mutex); } static int xen_memory_notifier(struct notifier_block *nb, unsigned long val, void *v) { if (val == MEM_ONLINE) schedule_delayed_work(&balloon_worker, 0); return NOTIFY_OK; } static struct notifier_block xen_memory_nb = { .notifier_call = xen_memory_notifier, .priority = 0 }; #else static enum bp_state reserve_additional_memory(void) { balloon_stats.target_pages = balloon_stats.current_pages; return BP_ECANCELED; } #endif /* CONFIG_XEN_BALLOON_MEMORY_HOTPLUG */ static long current_credit(void) { return balloon_stats.target_pages - balloon_stats.current_pages; } static bool balloon_is_inflated(void) { return balloon_stats.balloon_low || balloon_stats.balloon_high; } static enum bp_state increase_reservation(unsigned long nr_pages) { int rc; unsigned long i; struct page *page; if (nr_pages > ARRAY_SIZE(frame_list)) nr_pages = ARRAY_SIZE(frame_list); page = list_first_entry_or_null(&ballooned_pages, struct page, lru); for (i = 0; i < nr_pages; i++) { if (!page) { nr_pages = i; break; } frame_list[i] = page_to_xen_pfn(page); page = balloon_next_page(page); } rc = xenmem_reservation_increase(nr_pages, frame_list); if (rc <= 0) return BP_EAGAIN; for (i = 0; i < rc; i++) { page = balloon_retrieve(false); BUG_ON(page == NULL); xenmem_reservation_va_mapping_update(1, &page, &frame_list[i]); /* Relinquish the page back to the allocator. */ __ClearPageOffline(page); free_reserved_page(page); } balloon_stats.current_pages += rc; return BP_DONE; } static enum bp_state decrease_reservation(unsigned long nr_pages, gfp_t gfp) { enum bp_state state = BP_DONE; unsigned long i; struct page *page, *tmp; int ret; LIST_HEAD(pages); if (nr_pages > ARRAY_SIZE(frame_list)) nr_pages = ARRAY_SIZE(frame_list); for (i = 0; i < nr_pages; i++) { page = alloc_page(gfp); if (page == NULL) { nr_pages = i; state = BP_EAGAIN; break; } __SetPageOffline(page); adjust_managed_page_count(page, -1); xenmem_reservation_scrub_page(page); list_add(&page->lru, &pages); } /* * Ensure that ballooned highmem pages don't have kmaps. * * Do this before changing the p2m as kmap_flush_unused() * reads PTEs to obtain pages (and hence needs the original * p2m entry). */ kmap_flush_unused(); /* * Setup the frame, update direct mapping, invalidate P2M, * and add to balloon. */ i = 0; list_for_each_entry_safe(page, tmp, &pages, lru) { frame_list[i++] = xen_page_to_gfn(page); xenmem_reservation_va_mapping_reset(1, &page); list_del(&page->lru); balloon_append(page); } flush_tlb_all(); ret = xenmem_reservation_decrease(nr_pages, frame_list); BUG_ON(ret != nr_pages); balloon_stats.current_pages -= nr_pages; return state; } /* * As this is a work item it is guaranteed to run as a single instance only. * We may of course race updates of the target counts (which are protected * by the balloon lock), or with changes to the Xen hard limit, but we will * recover from these in time. */ static void balloon_process(struct work_struct *work) { enum bp_state state = BP_DONE; long credit; do { mutex_lock(&balloon_mutex); credit = current_credit(); if (credit > 0) { if (balloon_is_inflated()) state = increase_reservation(credit); else state = reserve_additional_memory(); } if (credit < 0) state = decrease_reservation(-credit, GFP_BALLOON); state = update_schedule(state); mutex_unlock(&balloon_mutex); cond_resched(); } while (credit && state == BP_DONE); /* Schedule more work if there is some still to be done. */ if (state == BP_EAGAIN) schedule_delayed_work(&balloon_worker, balloon_stats.schedule_delay * HZ); } /* Resets the Xen limit, sets new target, and kicks off processing. */ void balloon_set_new_target(unsigned long target) { /* No need for lock. Not read-modify-write updates. */ balloon_stats.target_pages = target; schedule_delayed_work(&balloon_worker, 0); } EXPORT_SYMBOL_GPL(balloon_set_new_target); static int add_ballooned_pages(int nr_pages) { enum bp_state st; if (xen_hotplug_unpopulated) { st = reserve_additional_memory(); if (st != BP_ECANCELED) { mutex_unlock(&balloon_mutex); wait_event(balloon_wq, !list_empty(&ballooned_pages)); mutex_lock(&balloon_mutex); return 0; } } st = decrease_reservation(nr_pages, GFP_USER); if (st != BP_DONE) return -ENOMEM; return 0; } /** * alloc_xenballooned_pages - get pages that have been ballooned out * @nr_pages: Number of pages to get * @pages: pages returned * @return 0 on success, error otherwise */ int alloc_xenballooned_pages(int nr_pages, struct page **pages) { int pgno = 0; struct page *page; int ret; mutex_lock(&balloon_mutex); balloon_stats.target_unpopulated += nr_pages; while (pgno < nr_pages) { page = balloon_retrieve(true); if (page) { __ClearPageOffline(page); pages[pgno++] = page; #ifdef CONFIG_XEN_HAVE_PVMMU /* * We don't support PV MMU when Linux and Xen is using * different page granularity. */ BUILD_BUG_ON(XEN_PAGE_SIZE != PAGE_SIZE); if (!xen_feature(XENFEAT_auto_translated_physmap)) { ret = xen_alloc_p2m_entry(page_to_pfn(page)); if (ret < 0) goto out_undo; } #endif } else { ret = add_ballooned_pages(nr_pages - pgno); if (ret < 0) goto out_undo; } } mutex_unlock(&balloon_mutex); return 0; out_undo: mutex_unlock(&balloon_mutex); free_xenballooned_pages(pgno, pages); return ret; } EXPORT_SYMBOL(alloc_xenballooned_pages); /** * free_xenballooned_pages - return pages retrieved with get_ballooned_pages * @nr_pages: Number of pages * @pages: pages to return */ void free_xenballooned_pages(int nr_pages, struct page **pages) { int i; mutex_lock(&balloon_mutex); for (i = 0; i < nr_pages; i++) { if (pages[i]) { __SetPageOffline(pages[i]); balloon_append(pages[i]); } } balloon_stats.target_unpopulated -= nr_pages; /* The balloon may be too large now. Shrink it if needed. */ if (current_credit()) schedule_delayed_work(&balloon_worker, 0); mutex_unlock(&balloon_mutex); } EXPORT_SYMBOL(free_xenballooned_pages); #ifdef CONFIG_XEN_PV static void __init balloon_add_region(unsigned long start_pfn, unsigned long pages) { unsigned long pfn, extra_pfn_end; struct page *page; /* * If the amount of usable memory has been limited (e.g., with * the 'mem' command line parameter), don't add pages beyond * this limit. */ extra_pfn_end = min(max_pfn, start_pfn + pages); for (pfn = start_pfn; pfn < extra_pfn_end; pfn++) { page = pfn_to_page(pfn); /* totalram_pages and totalhigh_pages do not include the boot-time balloon extension, so don't subtract from it. */ __balloon_append(page); } balloon_stats.total_pages += extra_pfn_end - start_pfn; } #endif static int __init balloon_init(void) { if (!xen_domain()) return -ENODEV; pr_info("Initialising balloon driver\n"); #ifdef CONFIG_XEN_PV balloon_stats.current_pages = xen_pv_domain() ? min(xen_start_info->nr_pages - xen_released_pages, max_pfn) : get_num_physpages(); #else balloon_stats.current_pages = get_num_physpages(); #endif balloon_stats.target_pages = balloon_stats.current_pages; balloon_stats.balloon_low = 0; balloon_stats.balloon_high = 0; balloon_stats.total_pages = balloon_stats.current_pages; balloon_stats.schedule_delay = 1; balloon_stats.max_schedule_delay = 32; balloon_stats.retry_count = 1; balloon_stats.max_retry_count = RETRY_UNLIMITED; #ifdef CONFIG_XEN_BALLOON_MEMORY_HOTPLUG set_online_page_callback(&xen_online_page); register_memory_notifier(&xen_memory_nb); register_sysctl_table(xen_root); #endif #ifdef CONFIG_XEN_PV { int i; /* * Initialize the balloon with pages from the extra memory * regions (see arch/x86/xen/setup.c). */ for (i = 0; i < XEN_EXTRA_MEM_MAX_REGIONS; i++) if (xen_extra_mem[i].n_pfns) balloon_add_region(xen_extra_mem[i].start_pfn, xen_extra_mem[i].n_pfns); } #endif /* Init the xen-balloon driver. */ xen_balloon_init(); return 0; } subsys_initcall(balloon_init);
Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.
Created with Cregit http://github.com/cregit/cregit
Version 2.0-RC1