Merge pull request #738 from ceph/wip-cache-crc

fix cached crc, bug #6583

Reviewed-by: Samuel Just <sam.just@inktank.com>

1 files changed, 17 insertions, 12 deletions

diff --git a/src/common/buffer.cc b/src/common/buffer.cc
index 4aa03ae4131..49307055715 100644
--- a/src/common/buffer.cc
+++ b/src/common/buffer.cc
@@ -77,13 +77,11 @@ static uint32_t simple_spinlock_t buffer_debug_lock = SIMPLE_SPINLOCK_INITIALIZE
     atomic_t nref;
 
     Spinlock crc_lock;
-    map<pair<off_t, off_t>, pair<int64_t, int64_t> > crc_map;
-    int64_t crc_in;   ///< cached crc base; -1 if invalid
-    int64_t crc_out;  ///< cached crc value; -1 if invalid
+    map<pair<size_t, size_t>, pair<uint32_t, uint32_t> > crc_map;
 
-    raw(unsigned l) : data(NULL), len(l), nref(0), crc_in(-1), crc_out(-1)
+    raw(unsigned l) : data(NULL), len(l), nref(0)
     { }
-    raw(char *c, unsigned l) : data(c), len(l), nref(0), crc_in(-1), crc_out(-1)
+    raw(char *c, unsigned l) : data(c), len(l), nref(0)
     { }
     virtual ~raw() {};
 
@@ -108,21 +106,25 @@ static uint32_t simple_spinlock_t buffer_debug_lock = SIMPLE_SPINLOCK_INITIALIZE
     bool is_n_page_sized() {
       return (len & ~CEPH_PAGE_MASK) == 0;
     }
-    bool get_crc(const pair<off_t, off_t> &fromto,
-		 pair<int64_t, int64_t> *crc) const {
+    bool get_crc(const pair<size_t, size_t> &fromto,
+		 pair<uint32_t, uint32_t> *crc) const {
       Spinlock::Locker l(crc_lock);
-      map<pair<off_t, off_t>, pair<int64_t, int64_t> >::const_iterator i =
+      map<pair<size_t, size_t>, pair<uint32_t, uint32_t> >::const_iterator i =
 	crc_map.find(fromto);
       if (i == crc_map.end())
 	return false;
       *crc = i->second;
       return true;
     }
-    void set_crc(const pair<off_t, off_t> &fromto,
-		 const pair<uint64_t, uint64_t> &crc) {
+    void set_crc(const pair<size_t, size_t> &fromto,
+		 const pair<uint32_t, uint32_t> &crc) {
       Spinlock::Locker l(crc_lock);
       crc_map[fromto] = crc;
     }
+    void invalidate_crc() {
+      Spinlock::Locker l(crc_lock);
+      crc_map.clear();
+    }
   };
 
   class buffer::raw_malloc : public buffer::raw {
@@ -453,17 +455,20 @@ static uint32_t simple_spinlock_t buffer_debug_lock = SIMPLE_SPINLOCK_INITIALIZE
     assert(_raw);
     assert(o <= _len);
     assert(o+l <= _len);
+    _raw->invalidate_crc();
     memcpy(c_str()+o, src, l);
   }
 
   void buffer::ptr::zero()
   {
+    _raw->invalidate_crc();
     memset(c_str(), 0, _len);
   }
 
   void buffer::ptr::zero(unsigned o, unsigned l)
   {
     assert(o+l <= _len);
+    _raw->invalidate_crc();
     memset(c_str()+o, 0, l);
   }
 
@@ -1317,8 +1322,8 @@ __u32 buffer::list::crc32c(__u32 crc) const
        ++it) {
     if (it->length()) {
       raw *r = it->get_raw();
-      pair<off_t, off_t> ofs(it->offset(), it->offset() + it->length());
-      pair<int64_t, int64_t> ccrc;
+      pair<size_t, size_t> ofs(it->offset(), it->offset() + it->length());
+      pair<uint32_t, uint32_t> ccrc;
       if (r->get_crc(ofs, &ccrc)) {
 	if (ccrc.first == crc) {
 	  // got it already