From 66a0e2d579dbec5c676cfe446234ffebb267c564 Mon Sep 17 00:00:00 2001 From: Ilya Dryomov Date: Tue, 31 Jan 2017 15:55:06 +0100 Subject: crush: remove mutable part of CRUSH map Then add it to the working state. It would be very nice if we didn't have to take a lock to calculate a crush placement. By moving the permutation array into the working data, we can treat the CRUSH map as immutable. Reflects ceph.git commit cbcd039651c0569551cb90d26ce27e1432671f2a. Signed-off-by: Ilya Dryomov --- include/linux/crush/mapper.h | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'include/linux/crush/mapper.h') diff --git a/include/linux/crush/mapper.h b/include/linux/crush/mapper.h index 5dfd5b1125d2..3303c7fd8a31 100644 --- a/include/linux/crush/mapper.h +++ b/include/linux/crush/mapper.h @@ -15,6 +15,8 @@ extern int crush_do_rule(const struct crush_map *map, int ruleno, int x, int *result, int result_max, const __u32 *weights, int weight_max, - int *scratch); + void *cwin, int *scratch); + +void crush_init_workspace(const struct crush_map *map, void *v); #endif -- cgit v1.2.3 From 743efcffffc6620ab44ea9ec67c7e4e28dfa7742 Mon Sep 17 00:00:00 2001 From: Ilya Dryomov Date: Tue, 31 Jan 2017 15:55:06 +0100 Subject: crush: merge working data and scratch Much like Arlo Guthrie, I decided that one big pile is better than two little piles. Reflects ceph.git commit 95c2df6c7e0b22d2ea9d91db500cf8b9441c73ba. Signed-off-by: Ilya Dryomov --- include/linux/crush/mapper.h | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-) (limited to 'include/linux/crush/mapper.h') diff --git a/include/linux/crush/mapper.h b/include/linux/crush/mapper.h index 3303c7fd8a31..c95e19e1ff11 100644 --- a/include/linux/crush/mapper.h +++ b/include/linux/crush/mapper.h @@ -15,7 +15,19 @@ extern int crush_do_rule(const struct crush_map *map, int ruleno, int x, int *result, int result_max, const __u32 *weights, int weight_max, - void *cwin, int *scratch); + void *cwin); + +/* + * Returns the exact amount of workspace that will need to be used + * for a given combination of crush_map and result_max. The caller can + * then allocate this much on its own, either on the stack, in a + * per-thread long-lived buffer, or however it likes. + */ +static inline size_t crush_work_size(const struct crush_map *map, + int result_max) +{ + return map->working_size + result_max * 3 * sizeof(__u32); +} void crush_init_workspace(const struct crush_map *map, void *v); -- cgit v1.2.3