From d390bb2a83086f2b79c152e2c1734813bd257d9b Mon Sep 17 00:00:00 2001 From: Ilya Dryomov Date: Tue, 24 Dec 2013 21:19:26 +0200 Subject: [PATCH] crush: generalize descend_once The legacy behavior is to make the normal number of tries for the recursive chooseleaf call. The descend_once tunable changed this to making a single try and bail if we get a reject (note that it is impossible to collide in the recursive case). The new set_chooseleaf_tries lets you select the number of recursive chooseleaf attempts for indep mode, or default to 1. Use the same behavior for firstn, except default to total_tries when the legacy tunables are set (for compatibility). This makes the rule step override the (new) default of 1 recursive attempt, keeping behavior consistent with indep mode. Reflects ceph.git commit 685c6950ef3df325ef04ce7c986e36ca2514c5f1. Signed-off-by: Ilya Dryomov Reviewed-by: Sage Weil --- net/ceph/crush/mapper.c | 25 ++++++++++++++----------- 1 file changed, 14 insertions(+), 11 deletions(-) diff --git a/net/ceph/crush/mapper.c b/net/ceph/crush/mapper.c index e9256a3..0613dd2 100644 --- a/net/ceph/crush/mapper.c +++ b/net/ceph/crush/mapper.c @@ -291,7 +291,6 @@ static int is_out(const struct crush_map *map, * @out: pointer to output vector * @outpos: our position in that vector * @recurse_to_leaf: true if we want one device under each item of given type - * @descend_once: true if we should only try one descent before giving up * @out2: second output vector for leaf items (if @recurse_to_leaf) */ static int crush_choose_firstn(const struct crush_map *map, @@ -302,7 +301,7 @@ static int crush_choose_firstn(const struct crush_map *map, unsigned int attempts, unsigned int recurse_attempts, int recurse_to_leaf, - int descend_once, int *out2) + int *out2) { int rep; unsigned int ftotal, flocal; @@ -389,7 +388,6 @@ static int crush_choose_firstn(const struct crush_map *map, out2, outpos, recurse_attempts, 0, 0, - map->chooseleaf_descend_once, NULL) <= outpos) /* didn't get leaf */ reject = 1; @@ -414,10 +412,7 @@ reject: ftotal++; flocal++; - if (reject && descend_once) - /* let outer call try again */ - skip_rep = 1; - else if (collide && flocal <= map->choose_local_tries) + if (collide && flocal <= map->choose_local_tries) /* retry locally a few times */ retry_bucket = 1; else if (map->choose_local_fallback_tries > 0 && @@ -639,7 +634,6 @@ int crush_do_rule(const struct crush_map *map, int numrep; int choose_tries = map->choose_total_tries; int choose_leaf_tries = 0; - const int descend_once = 0; if ((__u32)ruleno >= map->max_rules) { dprintk(" bad ruleno %d\n", ruleno); @@ -703,6 +697,14 @@ int crush_do_rule(const struct crush_map *map, } j = 0; if (firstn) { + int recurse_tries; + if (choose_leaf_tries) + recurse_tries = + choose_leaf_tries; + else if (map->chooseleaf_descend_once) + recurse_tries = 1; + else + recurse_tries = choose_tries; osize += crush_choose_firstn( map, map->buckets[-1-w[i]], @@ -711,9 +713,9 @@ int crush_do_rule(const struct crush_map *map, curstep->arg2, o+osize, j, choose_tries, - choose_leaf_tries ? choose_leaf_tries : choose_tries, + recurse_tries, recurse_to_leaf, - descend_once, c+osize); + c+osize); } else { crush_choose_indep( map, @@ -723,7 +725,8 @@ int crush_do_rule(const struct crush_map *map, curstep->arg2, o+osize, j, choose_tries, - choose_leaf_tries ? choose_leaf_tries : 1, + choose_leaf_tries ? + choose_leaf_tries : 1, recurse_to_leaf, c+osize, 0); -- 2.7.4