From de5a77d8422fc7ed0b2f4349bceb65a1a639e5b2 Mon Sep 17 00:00:00 2001 From: David Vrabel Date: Thu, 25 Jun 2015 12:08:20 +0100 Subject: xen/balloon: rationalize memory hotplug stats The stats used for memory hotplug make no sense and are fiddled with in odd ways. Remove them and introduce total_pages to track the total number of pages (both populated and unpopulated) including those within hotplugged regions (note that this includes not yet onlined pages). This will be used in a subsequent commit (xen/balloon: only hotplug additional memory if required) when deciding whether additional memory needs to be hotplugged. Signed-off-by: David Vrabel Reviewed-by: Daniel Kiper --- drivers/xen/balloon.c | 75 +++++++++------------------------------------------ 1 file changed, 12 insertions(+), 63 deletions(-) (limited to 'drivers/xen/balloon.c') diff --git a/drivers/xen/balloon.c b/drivers/xen/balloon.c index 095bb6789731..ac8054765127 100644 --- a/drivers/xen/balloon.c +++ b/drivers/xen/balloon.c @@ -194,21 +194,6 @@ static enum bp_state update_schedule(enum bp_state state) } #ifdef CONFIG_XEN_BALLOON_MEMORY_HOTPLUG -static long current_credit(void) -{ - return balloon_stats.target_pages - balloon_stats.current_pages - - balloon_stats.hotplug_pages; -} - -static bool balloon_is_inflated(void) -{ - if (balloon_stats.balloon_low || balloon_stats.balloon_high || - balloon_stats.balloon_hotplug) - return true; - else - return false; -} - static struct resource *additional_memory_resource(phys_addr_t size) { struct resource *res; @@ -289,10 +274,7 @@ static enum bp_state reserve_additional_memory(long credit) goto err; } - balloon_hotplug -= credit; - - balloon_stats.hotplug_pages += credit; - balloon_stats.balloon_hotplug = balloon_hotplug; + balloon_stats.total_pages += balloon_hotplug; return BP_DONE; err: @@ -308,11 +290,6 @@ static void xen_online_page(struct page *page) __balloon_append(page); - if (balloon_stats.hotplug_pages) - --balloon_stats.hotplug_pages; - else - --balloon_stats.balloon_hotplug; - mutex_unlock(&balloon_mutex); } @@ -329,32 +306,22 @@ static struct notifier_block xen_memory_nb = { .priority = 0 }; #else -static long current_credit(void) +static enum bp_state reserve_additional_memory(long credit) { - unsigned long target = balloon_stats.target_pages; - - target = min(target, - balloon_stats.current_pages + - balloon_stats.balloon_low + - balloon_stats.balloon_high); - - return target - balloon_stats.current_pages; + balloon_stats.target_pages = balloon_stats.current_pages; + return BP_DONE; } +#endif /* CONFIG_XEN_BALLOON_MEMORY_HOTPLUG */ -static bool balloon_is_inflated(void) +static long current_credit(void) { - if (balloon_stats.balloon_low || balloon_stats.balloon_high) - return true; - else - return false; + return balloon_stats.target_pages - balloon_stats.current_pages; } -static enum bp_state reserve_additional_memory(long credit) +static bool balloon_is_inflated(void) { - balloon_stats.target_pages = balloon_stats.current_pages; - return BP_DONE; + return balloon_stats.balloon_low || balloon_stats.balloon_high; } -#endif /* CONFIG_XEN_BALLOON_MEMORY_HOTPLUG */ static enum bp_state increase_reservation(unsigned long nr_pages) { @@ -367,15 +334,6 @@ static enum bp_state increase_reservation(unsigned long nr_pages) .domid = DOMID_SELF }; -#ifdef CONFIG_XEN_BALLOON_MEMORY_HOTPLUG - if (!balloon_stats.balloon_low && !balloon_stats.balloon_high) { - nr_pages = min(nr_pages, balloon_stats.balloon_hotplug); - balloon_stats.hotplug_pages += nr_pages; - balloon_stats.balloon_hotplug -= nr_pages; - return BP_DONE; - } -#endif - if (nr_pages > ARRAY_SIZE(frame_list)) nr_pages = ARRAY_SIZE(frame_list); @@ -438,15 +396,6 @@ static enum bp_state decrease_reservation(unsigned long nr_pages, gfp_t gfp) .domid = DOMID_SELF }; -#ifdef CONFIG_XEN_BALLOON_MEMORY_HOTPLUG - if (balloon_stats.hotplug_pages) { - nr_pages = min(nr_pages, balloon_stats.hotplug_pages); - balloon_stats.hotplug_pages -= nr_pages; - balloon_stats.balloon_hotplug += nr_pages; - return BP_DONE; - } -#endif - if (nr_pages > ARRAY_SIZE(frame_list)) nr_pages = ARRAY_SIZE(frame_list); @@ -635,6 +584,8 @@ static void __init balloon_add_region(unsigned long start_pfn, don't subtract from it. */ __balloon_append(page); } + + balloon_stats.total_pages += extra_pfn_end - start_pfn; } static int __init balloon_init(void) @@ -652,6 +603,7 @@ static int __init balloon_init(void) 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; @@ -659,9 +611,6 @@ static int __init balloon_init(void) balloon_stats.max_retry_count = RETRY_UNLIMITED; #ifdef CONFIG_XEN_BALLOON_MEMORY_HOTPLUG - balloon_stats.hotplug_pages = 0; - balloon_stats.balloon_hotplug = 0; - set_online_page_callback(&xen_online_page); register_memory_notifier(&xen_memory_nb); #endif -- cgit v1.2.1