Stefano Stabellini
2012-Mar-29 14:04 UTC
[PATCH v2 2/2] m2p_find_override: use list_for_each_entry_safe
Use list_for_each_entry_safe and remove the spin_lock acquisition in m2p_find_override: getting stale entries is OK because we should never get an m2p_find_override call looking for an entry that we are about to add or delete. Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> --- arch/x86/xen/p2m.c | 9 ++------- 1 files changed, 2 insertions(+), 7 deletions(-) diff --git a/arch/x86/xen/p2m.c b/arch/x86/xen/p2m.c index 1b267e7..a4d35d4 100644 --- a/arch/x86/xen/p2m.c +++ b/arch/x86/xen/p2m.c @@ -807,23 +807,18 @@ EXPORT_SYMBOL_GPL(m2p_remove_override); struct page *m2p_find_override(unsigned long mfn) { - unsigned long flags; struct list_head *bucket = &m2p_overrides[mfn_hash(mfn)]; - struct page *p, *ret; + struct page *p, *t, *ret; ret = NULL; - spin_lock_irqsave(&m2p_override_lock, flags); - - list_for_each_entry(p, bucket, lru) { + list_for_each_entry_safe(p, t, bucket, lru) { if (page_private(p) == mfn) { ret = p; break; } } - spin_unlock_irqrestore(&m2p_override_lock, flags); - return ret; } -- 1.7.2.5
Possibly Parallel Threads
- [PATCH] xen/grant-table: Refactor gnttab_[un]map_refs to avoid m2p_override
- [PATCH] xen/grant-table: Refactor gnttab_[un]map_refs to avoid m2p_override
- [PATCH v3 1/2] xen: enter/exit lazy_mmu_mode around m2p_override calls
- What went in Linux 3.5 from Xen standpoint.
- [PATCH] xen/gnttab: leave lazy MMU mode in the case of a m2p override failure