bio: skip atomic inc/dec of ->bi_cnt for most use cases

[mirror_ubuntu-zesty-kernel.git] / include / linux / blk_types.h

diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h
index 8b07e06038871bd3a0bdd09a8fd9313ab688d6ea..93d2e715381695baaf6fde81ad5937efffc94d4b 100644 (file)
--- a/include/linux/blk_types.h
+++ b/include/linux/blk_types.h
@@ -92,7 +92,7 @@ struct bio {
 
        unsigned short          bi_max_vecs;    /* max bvl_vecs we can hold */
 
-       atomic_t                bi_cnt;         /* pin count */
+       atomic_t                __bi_cnt;       /* pin count */
 
        struct bio_vec          *bi_io_vec;     /* the actual vec list */
 
@@ -123,6 +123,7 @@ struct bio {
 #define BIO_QUIET      9       /* Make BIO Quiet */
 #define BIO_SNAP_STABLE        10      /* bio data must be snapshotted during write */
 #define BIO_CHAIN      11      /* chained bio, ->bi_remaining in effect */
+#define BIO_REFFED     12      /* bio has elevated ->bi_cnt */
 
 /*
  * Flags starting here get preserved by bio_reset() - this includes