diff options
| -rw-r--r-- | mm/vmscan.c | 65 |
1 files changed, 44 insertions, 21 deletions
diff --git a/mm/vmscan.c b/mm/vmscan.c index 259f8208a388..d4f37634194e 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -1638,6 +1638,13 @@ static int vmscan_swappiness(struct scan_control *sc) return mem_cgroup_swappiness(sc->target_mem_cgroup); } +enum scan_balance { + SCAN_EQUAL, + SCAN_FRACT, + SCAN_ANON, + SCAN_FILE, +}; + /* * Determine how aggressively the anon and file LRU lists should be * scanned. The relative value of each set of LRU lists is determined @@ -1650,14 +1657,16 @@ static int vmscan_swappiness(struct scan_control *sc) static void get_scan_count(struct lruvec *lruvec, struct scan_control *sc, unsigned long *nr) { - unsigned long anon, file, free; + struct zone_reclaim_stat *reclaim_stat = &lruvec->reclaim_stat; + u64 fraction[2]; + u64 denominator = 0; /* gcc */ + struct zone *zone = lruvec_zone(lruvec); unsigned long anon_prio, file_prio; + enum scan_balance scan_balance; + unsigned long anon, file, free; + bool force_scan = false; unsigned long ap, fp; - struct zone_reclaim_stat *reclaim_stat = &lruvec->reclaim_stat; - u64 fraction[2], denominator; enum lru_list lru; - bool force_scan = false; - struct zone *zone = lruvec_zone(lruvec); /* * If the zone or memcg is small, nr[l] can be 0. This @@ -1676,9 +1685,7 @@ static void get_scan_count(struct lruvec *lruvec, struct scan_control *sc, /* If we have no swap space, do not bother scanning anon pages. */ if (!sc->may_swap || (nr_swap_pages <= 0)) { - fraction[0] = 0; - fraction[1] = 1; - denominator = 1; + scan_balance = SCAN_FILE; goto out; } @@ -1690,9 +1697,7 @@ static void get_scan_count(struct lruvec *lruvec, struct scan_control *sc, * too expensive. */ if (!global_reclaim(sc) && !vmscan_swappiness(sc)) { - fraction[0] = 0; - fraction[1] = 1; - denominator = 1; + scan_balance = SCAN_FILE; goto out; } @@ -1702,9 +1707,7 @@ static void get_scan_count(struct lruvec *lruvec, struct scan_control *sc, * (unless the swappiness setting disagrees with swapping). */ if (!sc->priority && vmscan_swappiness(sc)) { - fraction[0] = 1; - fraction[1] = 1; - denominator = 1; + scan_balance = SCAN_EQUAL; goto out; } @@ -1722,9 +1725,7 @@ static void get_scan_count(struct lruvec *lruvec, struct scan_control *sc, if (global_reclaim(sc)) { free = zone_page_state(zone, NR_FREE_PAGES); if (unlikely(file + free <= high_wmark_pages(zone))) { - fraction[0] = 1; - fraction[1] = 0; - denominator = 1; + scan_balance = SCAN_ANON; goto out; } } @@ -1734,12 +1735,12 @@ static void get_scan_count(struct lruvec *lruvec, struct scan_control *sc, * anything from the anonymous working set right now. */ if (!inactive_file_is_low(lruvec)) { - fraction[0] = 0; - fraction[1] = 1; - denominator = 1; + scan_balance = SCAN_FILE; goto out; } + scan_balance = SCAN_FRACT; + /* * With swappiness at 100, anonymous and file have the same priority. * This scanning priority is essentially the inverse of IO cost. @@ -1792,9 +1793,31 @@ out: size = get_lru_size(lruvec, lru); scan = size >> sc->priority; + if (!scan && force_scan) scan = min(size, SWAP_CLUSTER_MAX); - scan = div64_u64(scan * fraction[file], denominator); + + switch (scan_balance) { + case SCAN_EQUAL: + /* Scan lists relative to size */ + break; + case SCAN_FRACT: + /* + * Scan types proportional to swappiness and + * their relative recent reclaim efficiency. + */ + scan = div64_u64(scan * fraction[file], denominator); + break; + case SCAN_FILE: + case SCAN_ANON: + /* Scan one type exclusively */ + if ((scan_balance == SCAN_FILE) != file) + scan = 0; + break; + default: + /* Look ma, no brain */ + BUG(); + } nr[lru] = scan; } } |