From: NeilBrown Date: Thu, 13 Dec 2018 00:32:56 +0000 (+1100) Subject: LU-9679 osc: simplify osc_extent_find() X-Git-Tag: 2.13.55~88 X-Git-Url: https://git.whamcloud.com/?p=fs%2Flustre-release.git;a=commitdiff_plain;h=80e21cce3dd6748fd760786cafe9c26d502fd74f LU-9679 osc: simplify osc_extent_find() osc_extent_find() contains some code with the same functionality as osc_extent_merge(). So replace that code with a call to osc_extent_merge(). This requires that we set cur->oe_grants earlier, as osc_extent_merge() needs that. Also: - fix a pre-existing bug - osc_extent_merge() should never try to merge two extends with different ->oe_mppr as later alignment checks can get confused. - Remove a redundant list_del_init() which is already included in __osc_extent_remove(). Linux-Commit: 85ebb57ddc5b ("lustre: osc: simplify osc_extent_find()") Signed-off-by: Mr NeilBrown Change-Id: I5fa56e04ed707ee91f99179030dae4bd45456061 Signed-off-by: Mr NeilBrown Reviewed-on: https://review.whamcloud.com/37607 Tested-by: jenkins Tested-by: Maloo Reviewed-by: Andreas Dilger Reviewed-by: James Simmons Reviewed-by: Oleg Drokin --- diff --git a/lustre/osc/osc_cache.c b/lustre/osc/osc_cache.c index 613a056..e0c9901 100644 --- 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; + /* + * 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; @@ -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); - list_del_init(&victim->oe_link); 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_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); @@ -758,54 +765,21 @@ restart: * 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; - 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; - found = osc_extent_hold(ext); - } - if (found != NULL) break; + } } 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); - cur->oe_grants = chunksize + cli->cl_grant_extent_tax; LASSERT(*grants >= cur->oe_grants); *grants -= cur->oe_grants;