xnu-4903.231.4.tar.gz

[apple/xnu.git] / osfmk / kern / btlog.c

diff --git a/osfmk/kern/btlog.c b/osfmk/kern/btlog.c
index 80a4799615a41d2e371687465409a045c0ae6560..a15aef98046324084695bb0f9d2c8395568ec9b7 100644 (file)
--- a/osfmk/kern/btlog.c
+++ b/osfmk/kern/btlog.c
@@ -837,4 +837,66 @@ btlog_copy_backtraces_for_elements(btlog_t      * btlog,
        btlog_unlock(btlog);
 }
 
        btlog_unlock(btlog);
 }
 

+/*
+ * Returns the number of records in the btlog struct.
+ *
+ * Called by the mach_zone_get_btlog_records() MIG routine.
+ */
+size_t
+get_btlog_records_count(btlog_t *btlog)
+{
+       if (btlog->btlog_buffersize < sizeof(btlog_t)) {
+               return 0;
+       }
+       return ((btlog->btlog_buffersize - sizeof(btlog_t))/btlog->btrecord_size);
+}
+
+/*
+ * Copies out relevant info from btlog_record_t's to zone_btrecord_t's. 'numrecs' points to the number of records
+ * the 'records' buffer can hold. Upon return 'numrecs' points to the number of records actually copied out.
+ *
+ * Called by the mach_zone_get_btlog_records() MIG routine.
+ */
+void
+get_btlog_records(btlog_t *btlog, zone_btrecord_t *records, unsigned int *numrecs)
+{
+       unsigned int count, recs_copied, frame;
+       zone_btrecord_t *current_rec;
+       btlog_record_t *zstack_record;
+       btlog_recordindex_t     zstack_index = BTLOG_RECORDINDEX_NONE;
+
+       btlog_lock(btlog);
+
+       count = 0;
+       if (btlog->btlog_buffersize > sizeof(btlog_t)) {
+               count = (unsigned int)((btlog->btlog_buffersize - sizeof(btlog_t))/btlog->btrecord_size);
+       }
+       /* Copy out only as many records as the pre-allocated buffer size permits. */
+       if (count > *numrecs) {
+               count = *numrecs;
+       }
+       zstack_index = btlog->head;
+
+       current_rec = &records[0];
+       recs_copied = 0;
+       while (recs_copied < count && (zstack_index != BTLOG_RECORDINDEX_NONE)) {
+               zstack_record = lookup_btrecord(btlog, zstack_index);
+               current_rec->operation_type = (uint32_t)(zstack_record->operation);
+               current_rec->ref_count = zstack_record->ref_count;
+
+               frame = 0;
+               while (frame < MIN(btlog->btrecord_btdepth, MAX_ZTRACE_DEPTH)) {
+                       current_rec->bt[frame] = (uint64_t)VM_KERNEL_UNSLIDE(zstack_record->bt[frame]);
+                       frame++;
+               }
+
+               zstack_index = zstack_record->next;
+               recs_copied++;
+               current_rec++;
+       }
+       *numrecs = recs_copied;
+
+       btlog_unlock(btlog);
+}
+

 #endif  /* DEBUG || DEVELOPMENT */
 #endif  /* DEBUG || DEVELOPMENT */