LU-9679 osc: simplify osc_extent_find()

[fs/lustre-release.git] / lustre / osc / osc_cache.c

diff --git a/lustre/osc/osc_cache.c b/lustre/osc/osc_cache.c
index 613a056..e0c9901 100644 (file)
--- a/lustre/osc/osc_cache.c
+++ b/lustre/osc/osc_cache.c
@@ -537,6 +537,14 @@ static int osc_extent_merge(const struct lu_env *env, struct osc_extent *cur,
        if (cur->oe_max_end != victim->oe_max_end)
                return -ERANGE;
 
        if (cur->oe_max_end != victim->oe_max_end)
                return -ERANGE;
 

+       /*
+        * In the rare case max_pages_per_rpc (mppr) is changed, don't
+        * merge extents until after old ones have been sent, or the
+        * "extents are aligned to RPCs" checks are unhappy.
+        */
+       if (cur->oe_mppr != victim->oe_mppr)
+               return -ERANGE;
+

        LASSERT(cur->oe_dlmlock == victim->oe_dlmlock);
        ppc_bits = osc_cli(obj)->cl_chunkbits - PAGE_SHIFT;
        chunk_start = cur->oe_start >> ppc_bits;
        LASSERT(cur->oe_dlmlock == victim->oe_dlmlock);
        ppc_bits = osc_cli(obj)->cl_chunkbits - PAGE_SHIFT;
        chunk_start = cur->oe_start >> ppc_bits;


@@ -562,7 +570,6 @@ static int osc_extent_merge(const struct lu_env *env, struct osc_extent *cur,
        cur->oe_urgent   |= victim->oe_urgent;
        cur->oe_memalloc |= victim->oe_memalloc;
        list_splice_init(&victim->oe_pages, &cur->oe_pages);
        cur->oe_urgent   |= victim->oe_urgent;
        cur->oe_memalloc |= victim->oe_memalloc;
        list_splice_init(&victim->oe_pages, &cur->oe_pages);

-       list_del_init(&victim->oe_link);

        victim->oe_nr_pages = 0;
 
        osc_extent_get(victim);
        victim->oe_nr_pages = 0;
 
        osc_extent_get(victim);


@@ -690,7 +697,7 @@ static struct osc_extent *osc_extent_find(const struct lu_env *env,
                cur->oe_start = descr->cld_start;
        if (cur->oe_end > max_end)
                cur->oe_end = max_end;
                cur->oe_start = descr->cld_start;
        if (cur->oe_end > max_end)
                cur->oe_end = max_end;

-       cur->oe_grants  = 0;
+       cur->oe_grants  = chunksize + cli->cl_grant_extent_tax;

        cur->oe_mppr    = max_pages;
        if (olck->ols_dlmlock != NULL) {
                LASSERT(olck->ols_hold);
        cur->oe_mppr    = max_pages;
        if (olck->ols_dlmlock != NULL) {
                LASSERT(olck->ols_hold);


@@ -758,54 +765,21 @@ restart:
                         * flushed, try next one. */
                        continue;
 
                         * flushed, try next one. */
                        continue;
 

-               /* check if they belong to the same rpc slot before trying to
-                * merge. the extents are not overlapped and contiguous at
-                * chunk level to get here. */
-               if (ext->oe_max_end != max_end)
-                       /* if they don't belong to the same RPC slot or
-                        * max_pages_per_rpc has ever changed, do not merge. */
-                       continue;
-
-               /* check whether maximum extent size will be hit */
-               if ((ext_chk_end - ext_chk_start + 1 + 1) << ppc_bits >
-                   cli->cl_max_extent_pages)
-                       continue;
-
-               /* it's required that an extent must be contiguous at chunk
-                * level so that we know the whole extent is covered by grant
-                * (the pages in the extent are NOT required to be contiguous).
-                * Otherwise, it will be too much difficult to know which
-                * chunks have grants allocated. */
-
-               /* try to do front merge - extend ext's start */
-               if (chunk + 1 == ext_chk_start) {
-                       /* ext must be chunk size aligned */
-                       EASSERT((ext->oe_start & ~chunk_mask) == 0, ext);
-
-                       /* pull ext's start back to cover cur */
-                       ext->oe_start   = cur->oe_start;
-                       ext->oe_grants += chunksize;
+               if (osc_extent_merge(env, ext, cur) == 0) {

                        LASSERT(*grants >= chunksize);
                        *grants -= chunksize;
                        LASSERT(*grants >= chunksize);
                        *grants -= chunksize;

-

                        found = osc_extent_hold(ext);
                        found = osc_extent_hold(ext);

-               } else if (chunk == ext_chk_end + 1) {
-                       /* rear merge */
-                       ext->oe_end     = cur->oe_end;
-                       ext->oe_grants += chunksize;
-                       LASSERT(*grants >= chunksize);
-                       *grants -= chunksize;

 
 

-                       /* try to merge with the next one because we just fill
-                        * in a gap */
+                       /*
+                        * Try to merge with the next one too because we
+                        * might have just filled in a gap.
+                        */

                        if (osc_extent_merge(env, ext, next_extent(ext)) == 0)
                                /* we can save extent tax from next extent */
                                *grants += cli->cl_grant_extent_tax;
 
                        if (osc_extent_merge(env, ext, next_extent(ext)) == 0)
                                /* we can save extent tax from next extent */
                                *grants += cli->cl_grant_extent_tax;
 

-                       found = osc_extent_hold(ext);
-               }
-               if (found != NULL)

                        break;
                        break;

+               }

        }
 
        osc_extent_tree_dump(D_CACHE, obj);
        }
 
        osc_extent_tree_dump(D_CACHE, obj);


@@ -819,7 +793,6 @@ restart:
        } else if (conflict == NULL) {
                /* create a new extent */
                EASSERT(osc_extent_is_overlapped(obj, cur) == 0, cur);
        } else if (conflict == NULL) {
                /* create a new extent */
                EASSERT(osc_extent_is_overlapped(obj, cur) == 0, cur);

-               cur->oe_grants = chunksize + cli->cl_grant_extent_tax;

                LASSERT(*grants >= cur->oe_grants);
                *grants -= cur->oe_grants;
 
                LASSERT(*grants >= cur->oe_grants);
                *grants -= cur->oe_grants;