diff options
Diffstat (limited to 'drivers/xen/grant-table.c')
| -rw-r--r-- | drivers/xen/grant-table.c | 60 |
1 files changed, 38 insertions, 22 deletions
diff --git a/drivers/xen/grant-table.c b/drivers/xen/grant-table.c index e1ec725c2819..3e76e33f6e08 100644 --- a/drivers/xen/grant-table.c +++ b/drivers/xen/grant-table.c @@ -427,16 +427,14 @@ EXPORT_SYMBOL_GPL(gnttab_grant_foreign_access); static int gnttab_end_foreign_access_ref_v1(grant_ref_t ref) { - u16 flags, nflags; - u16 *pflags; + u16 *pflags = &gnttab_shared.v1[ref].flags; + u16 flags; - pflags = &gnttab_shared.v1[ref].flags; - nflags = *pflags; + flags = *pflags; do { - flags = nflags; if (flags & (GTF_reading|GTF_writing)) return 0; - } while ((nflags = sync_cmpxchg(pflags, flags, 0)) != flags); + } while (!sync_try_cmpxchg(pflags, &flags, 0)); return 1; } @@ -498,14 +496,21 @@ static LIST_HEAD(deferred_list); static void gnttab_handle_deferred(struct timer_list *); static DEFINE_TIMER(deferred_timer, gnttab_handle_deferred); +static atomic64_t deferred_count; +static atomic64_t leaked_count; +static unsigned int free_per_iteration = 10; +module_param(free_per_iteration, uint, 0600); + static void gnttab_handle_deferred(struct timer_list *unused) { - unsigned int nr = 10; + unsigned int nr = READ_ONCE(free_per_iteration); + const bool ignore_limit = nr == 0; struct deferred_entry *first = NULL; unsigned long flags; + size_t freed = 0; spin_lock_irqsave(&gnttab_list_lock, flags); - while (nr--) { + while ((ignore_limit || nr--) && !list_empty(&deferred_list)) { struct deferred_entry *entry = list_first_entry(&deferred_list, struct deferred_entry, list); @@ -515,10 +520,14 @@ static void gnttab_handle_deferred(struct timer_list *unused) list_del(&entry->list); spin_unlock_irqrestore(&gnttab_list_lock, flags); if (_gnttab_end_foreign_access_ref(entry->ref)) { + uint64_t ret = atomic64_dec_return(&deferred_count); + put_free_entry(entry->ref); - pr_debug("freeing g.e. %#x (pfn %#lx)\n", - entry->ref, page_to_pfn(entry->page)); + pr_debug("freeing g.e. %#x (pfn %#lx), %llu remaining\n", + entry->ref, page_to_pfn(entry->page), + (unsigned long long)ret); put_page(entry->page); + freed++; kfree(entry); entry = NULL; } else { @@ -530,21 +539,22 @@ static void gnttab_handle_deferred(struct timer_list *unused) spin_lock_irqsave(&gnttab_list_lock, flags); if (entry) list_add_tail(&entry->list, &deferred_list); - else if (list_empty(&deferred_list)) - break; } - if (!list_empty(&deferred_list) && !timer_pending(&deferred_timer)) { + if (list_empty(&deferred_list)) + WARN_ON(atomic64_read(&deferred_count)); + else if (!timer_pending(&deferred_timer)) { deferred_timer.expires = jiffies + HZ; add_timer(&deferred_timer); } spin_unlock_irqrestore(&gnttab_list_lock, flags); + pr_debug("Freed %zu references", freed); } static void gnttab_add_deferred(grant_ref_t ref, struct page *page) { struct deferred_entry *entry; gfp_t gfp = (in_atomic() || irqs_disabled()) ? GFP_ATOMIC : GFP_KERNEL; - const char *what = KERN_WARNING "leaking"; + uint64_t leaked, deferred; entry = kmalloc(sizeof(*entry), gfp); if (!page) { @@ -567,10 +577,16 @@ static void gnttab_add_deferred(grant_ref_t ref, struct page *page) add_timer(&deferred_timer); } spin_unlock_irqrestore(&gnttab_list_lock, flags); - what = KERN_DEBUG "deferring"; + deferred = atomic64_inc_return(&deferred_count); + leaked = atomic64_read(&leaked_count); + pr_debug("deferring g.e. %#x (pfn %#lx) (total deferred %llu, total leaked %llu)\n", + ref, page ? page_to_pfn(page) : -1, deferred, leaked); + } else { + deferred = atomic64_read(&deferred_count); + leaked = atomic64_inc_return(&leaked_count); + pr_warn("leaking g.e. %#x (pfn %#lx) (total deferred %llu, total leaked %llu)\n", + ref, page ? page_to_pfn(page) : -1, deferred, leaked); } - printk("%s g.e. %#x (pfn %#lx)\n", - what, ref, page ? page_to_pfn(page) : -1); } int gnttab_try_end_foreign_access(grant_ref_t ref) @@ -1026,7 +1042,7 @@ EXPORT_SYMBOL_GPL(gnttab_pages_clear_private); /** * gnttab_free_pages - free pages allocated by gnttab_alloc_pages() - * @nr_pages; number of pages to free + * @nr_pages: number of pages to free * @pages: the pages */ void gnttab_free_pages(int nr_pages, struct page **pages) @@ -1188,7 +1204,7 @@ void gnttab_foreach_grant_in_range(struct page *page, unsigned int glen; unsigned long xen_pfn; - len = min_t(unsigned int, PAGE_SIZE - offset, len); + len = min(PAGE_SIZE - offset, len); goffset = xen_offset_in_page(offset); xen_pfn = page_to_xen_pfn(page) + XEN_PFN_DOWN(offset); @@ -1433,7 +1449,7 @@ static int gnttab_map(unsigned int start_idx, unsigned int end_idx) unsigned int nr_gframes = end_idx + 1; int rc; - if (xen_feature(XENFEAT_auto_translated_physmap)) { + if (!xen_pv_domain()) { struct xen_add_to_physmap xatp; unsigned int i = end_idx; rc = 0; @@ -1554,7 +1570,7 @@ static int gnttab_setup(void) if (max_nr_gframes < nr_grant_frames) return -ENOSYS; - if (xen_feature(XENFEAT_auto_translated_physmap) && gnttab_shared.addr == NULL) { + if (!xen_pv_domain() && gnttab_shared.addr == NULL) { gnttab_shared.addr = xen_auto_xlat_grant_frames.vaddr; if (gnttab_shared.addr == NULL) { pr_warn("gnttab share frames is not mapped!\n"); @@ -1572,7 +1588,7 @@ int gnttab_resume(void) int gnttab_suspend(void) { - if (!xen_feature(XENFEAT_auto_translated_physmap)) + if (xen_pv_domain()) gnttab_interface->unmap_frames(); return 0; } |