LU-4793 clio: Reduce memory overhead of per-page allocation

[fs/lustre-release.git] / lustre / include / cl_object.h

diff --git a/lustre/include/cl_object.h b/lustre/include/cl_object.h
index 286ecfa..5ad0067 100644 (file)
--- a/lustre/include/cl_object.h
+++ b/lustre/include/cl_object.h
@@ -701,17 +701,6 @@ enum cl_page_type {
 };
 
 /**
- * Flags maintained for every cl_page.
- */
-enum cl_page_flags {
-        /**
-         * Set when pagein completes. Used for debugging (read completes at
-         * most once for a page).
-         */
-        CPF_READ_COMPLETED = 1 << 0
-};
-
-/**
  * Fields are protected by the lock on struct page, except for atomics and
  * immutables.
  *
@@ -722,26 +711,24 @@ enum cl_page_flags {
  */
 struct cl_page {
        /** Reference counter. */
-       atomic_t                cp_ref;
+       atomic_t                 cp_ref;
+       /** Transfer error. */
+       int                      cp_error;
        /** An object this page is a part of. Immutable after creation. */
        struct cl_object        *cp_obj;
-       /** List of slices. Immutable after creation. */
-       cfs_list_t              cp_layers;
+       /** vmpage */
        struct page             *cp_vmpage;
+       /** Linkage of pages within group. Pages must be owned */
+       struct list_head         cp_batch;
+       /** List of slices. Immutable after creation. */
+       struct list_head         cp_layers;
+       /** Linkage of pages within cl_req. */
+       struct list_head         cp_flight;
        /**
         * Page state. This field is const to avoid accidental update, it is
         * modified only internally within cl_page.c. Protected by a VM lock.
         */
        const enum cl_page_state cp_state;
-       /** Linkage of pages within group. Protected by cl_page::cp_mutex. */
-       cfs_list_t              cp_batch;
-       /** Mutex serializing membership of a page in a batch. */
-       struct mutex            cp_mutex;
-        /** Linkage of pages within cl_req. */
-        cfs_list_t               cp_flight;
-        /** Transfer error. */
-        int                      cp_error;
-
         /**
          * Page type. Only CPT_TRANSIENT is used so far. Immutable after
          * creation.
@@ -754,10 +741,6 @@ struct cl_page {
          */
         struct cl_io            *cp_owner;
         /**
-         * Debug information, the task is owning the page.
-         */
-       struct task_struct      *cp_task;
-        /**
          * Owning IO request in cl_page_state::CPS_PAGEOUT and
          * cl_page_state::CPS_PAGEIN states. This field is maintained only in
          * the top-level pages. Protected by a VM lock.
@@ -769,8 +752,6 @@ struct cl_page {
        struct lu_ref_link       cp_obj_ref;
        /** Link to a queue, for debugging. */
        struct lu_ref_link       cp_queue_ref;
-       /** Per-page flags from enum cl_page_flags. Protected by a VM lock. */
-       unsigned                 cp_flags;
        /** Assigned if doing a sync_io */
        struct cl_sync_io       *cp_sync_io;
 };
@@ -2715,6 +2696,7 @@ static inline void cl_object_page_init(struct cl_object *clob, int size)
 {
        clob->co_slice_off = cl_object_header(clob)->coh_page_bufsize;
        cl_object_header(clob)->coh_page_bufsize += cfs_size_round(size);
+       WARN_ON(cl_object_header(clob)->coh_page_bufsize > 512);
 }
 
 static inline void *cl_object_page_slice(struct cl_object *clob,