From: Loic Dachary <ldachary@redhat.com>
Date: Fri, 5 May 2017 09:38:32 +0000 (+0200)
Subject: crush: update documentation for negative choose step
X-Git-Tag: v12.0.3~68^2
X-Git-Url: http://git.apps.os.sepia.ceph.com/?a=commitdiff_plain;h=dca1ae1e0a6b02029c3a7f9dec4114972be26d50;p=ceph-ci.git

crush: update documentation for negative choose step

And remove an obsolete comment.

Signed-off-by: Loic Dachary <loic@dachary.org>
---

diff --git a/src/crush/builder.h b/src/crush/builder.h
index 651729ff0e0..d2f4522a63e 100644
--- a/src/crush/builder.h
+++ b/src/crush/builder.h
@@ -87,10 +87,10 @@ extern struct crush_rule *crush_make_rule(int len, int ruleset, int type, int mi
  *     __arg1__ leaves within all the buckets of type __arg2__ and
  *     select them.
  *
- * In all __CHOOSE__ steps, if __arg1__ is zero, the number of items
- * to select is determined by the __max_result__ argument of
- * crush_do_rule(), i.e. __arg1__ is __max_result__ minus the number of
- * items already in the result.
+ * In all __CHOOSE__ steps, if __arg1__ is less than or equal to zero,
+ * the number of items to select is equal to the __max_result__ argument
+ * of crush_do_rule() minus __arg1__. It is common to set __arg1__ to zero
+ * to select as many items as requested by __max_result__.
  *
  * - __CRUSH_RULE_SET_CHOOSE_TRIES__ and __CRUSH_RULE_SET_CHOOSELEAF_TRIES__
  *
diff --git a/src/crush/mapper.c b/src/crush/mapper.c
index 9fc06e89a31..8176efcea10 100644
--- a/src/crush/mapper.c
+++ b/src/crush/mapper.c
@@ -994,11 +994,6 @@ int crush_do_rule(const struct crush_map *map,
 
 			for (i = 0; i < wsize; i++) {
 				int bno;
-				/*
-				 * see CRUSH_N, CRUSH_N_MINUS macros.
-				 * basically, numrep <= 0 means relative to
-				 * the provided result_max
-				 */
 				numrep = curstep->arg1;
 				if (numrep <= 0) {
 					numrep += result_max;