diff --git a/Documentation/admin-guide/cgroup-v2.rst b/Documentation/admin-guide/cgroup-v2.rst index 8fbb0519d556..3ef815845003 100644 --- a/Documentation/admin-guide/cgroup-v2.rst +++ b/Documentation/admin-guide/cgroup-v2.rst @@ -1299,17 +1299,10 @@ PAGE_SIZE multiple when read back. This is a simple interface to trigger memory reclaim in the target cgroup. - This file accepts a single key, the number of bytes to reclaim. - No nested keys are currently supported. - Example:: echo "1G" > memory.reclaim - The interface can be later extended with nested keys to - configure the reclaim behavior. For example, specify the - type of memory to reclaim from (anon, file, ..). - Please note that the kernel can over or under reclaim from the target cgroup. If less bytes are reclaimed than the specified amount, -EAGAIN is returned. @@ -1321,6 +1314,17 @@ PAGE_SIZE multiple when read back. This means that the networking layer will not adapt based on reclaim induced by memory.reclaim. +The following nested keys are defined. + + ========== ================================ + swappiness Swappiness value to reclaim with + ========== ================================ + + Specifying a swappiness value instructs the kernel to perform + the reclaim with that swappiness value. Note that this has the + same semantics as vm.swappiness applied to memcg reclaim with + all the existing limitations and potential future extensions. + memory.peak A read-only single value file which exists on non-root cgroups. diff --git a/include/linux/swap.h b/include/linux/swap.h index e97db0fa7659..3df75d62a835 100644 --- a/include/linux/swap.h +++ b/include/linux/swap.h @@ -409,7 +409,8 @@ extern unsigned long try_to_free_pages(struct zonelist *zonelist, int order, extern unsigned long try_to_free_mem_cgroup_pages(struct mem_cgroup *memcg, unsigned long nr_pages, gfp_t gfp_mask, - unsigned int reclaim_options); + unsigned int reclaim_options, + int *swappiness); extern unsigned long mem_cgroup_shrink_node(struct mem_cgroup *mem, gfp_t gfp_mask, bool noswap, pg_data_t *pgdat, diff --git a/mm/memcontrol-v1.c b/mm/memcontrol-v1.c index 98da8d0af4d0..a3ea4a5e8c96 100644 --- a/mm/memcontrol-v1.c +++ b/mm/memcontrol-v1.c @@ -2241,7 +2241,7 @@ static int mem_cgroup_resize_max(struct mem_cgroup *memcg, } if (!try_to_free_mem_cgroup_pages(memcg, 1, GFP_KERNEL, - memsw ? 0 : MEMCG_RECLAIM_MAY_SWAP)) { + memsw ? 0 : MEMCG_RECLAIM_MAY_SWAP, NULL)) { ret = -EBUSY; break; } @@ -2273,7 +2273,7 @@ static int mem_cgroup_force_empty(struct mem_cgroup *memcg) return -EINTR; if (!try_to_free_mem_cgroup_pages(memcg, 1, GFP_KERNEL, - MEMCG_RECLAIM_MAY_SWAP)) + MEMCG_RECLAIM_MAY_SWAP, NULL)) nr_retries--; } diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 53a8491634b9..6fb1c933e03a 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -48,6 +48,7 @@ #include #include #include +#include #include #include #include @@ -1921,7 +1922,8 @@ static unsigned long reclaim_high(struct mem_cgroup *memcg, psi_memstall_enter(&pflags); nr_reclaimed += try_to_free_mem_cgroup_pages(memcg, nr_pages, gfp_mask, - MEMCG_RECLAIM_MAY_SWAP); + MEMCG_RECLAIM_MAY_SWAP, + NULL); psi_memstall_leave(&pflags); } while ((memcg = parent_mem_cgroup(memcg)) && !mem_cgroup_is_root(memcg)); @@ -2227,7 +2229,7 @@ retry: psi_memstall_enter(&pflags); nr_reclaimed = try_to_free_mem_cgroup_pages(mem_over_limit, nr_pages, - gfp_mask, reclaim_options); + gfp_mask, reclaim_options, NULL); psi_memstall_leave(&pflags); if (mem_cgroup_margin(mem_over_limit) >= nr_pages) @@ -4097,7 +4099,7 @@ static ssize_t memory_high_write(struct kernfs_open_file *of, } reclaimed = try_to_free_mem_cgroup_pages(memcg, nr_pages - high, - GFP_KERNEL, MEMCG_RECLAIM_MAY_SWAP); + GFP_KERNEL, MEMCG_RECLAIM_MAY_SWAP, NULL); if (!reclaimed && !nr_retries--) break; @@ -4146,7 +4148,7 @@ static ssize_t memory_max_write(struct kernfs_open_file *of, if (nr_reclaims) { if (!try_to_free_mem_cgroup_pages(memcg, nr_pages - max, - GFP_KERNEL, MEMCG_RECLAIM_MAY_SWAP)) + GFP_KERNEL, MEMCG_RECLAIM_MAY_SWAP, NULL)) nr_reclaims--; continue; } @@ -4276,19 +4278,50 @@ static ssize_t memory_oom_group_write(struct kernfs_open_file *of, return nbytes; } +enum { + MEMORY_RECLAIM_SWAPPINESS = 0, + MEMORY_RECLAIM_NULL, +}; + +static const match_table_t tokens = { + { MEMORY_RECLAIM_SWAPPINESS, "swappiness=%d"}, + { MEMORY_RECLAIM_NULL, NULL }, +}; + static ssize_t memory_reclaim(struct kernfs_open_file *of, char *buf, size_t nbytes, loff_t off) { struct mem_cgroup *memcg = mem_cgroup_from_css(of_css(of)); unsigned int nr_retries = MAX_RECLAIM_RETRIES; unsigned long nr_to_reclaim, nr_reclaimed = 0; + int swappiness = -1; unsigned int reclaim_options; - int err; + char *old_buf, *start; + substring_t args[MAX_OPT_ARGS]; buf = strstrip(buf); - err = page_counter_memparse(buf, "", &nr_to_reclaim); - if (err) - return err; + + old_buf = buf; + nr_to_reclaim = memparse(buf, &buf) / PAGE_SIZE; + if (buf == old_buf) + return -EINVAL; + + buf = strstrip(buf); + + while ((start = strsep(&buf, " ")) != NULL) { + if (!strlen(start)) + continue; + switch (match_token(start, tokens, args)) { + case MEMORY_RECLAIM_SWAPPINESS: + if (match_int(&args[0], &swappiness)) + return -EINVAL; + if (swappiness < MIN_SWAPPINESS || swappiness > MAX_SWAPPINESS) + return -EINVAL; + break; + default: + return -EINVAL; + } + } reclaim_options = MEMCG_RECLAIM_MAY_SWAP | MEMCG_RECLAIM_PROACTIVE; while (nr_reclaimed < nr_to_reclaim) { @@ -4308,7 +4341,9 @@ static ssize_t memory_reclaim(struct kernfs_open_file *of, char *buf, lru_add_drain_all(); reclaimed = try_to_free_mem_cgroup_pages(memcg, - batch_size, GFP_KERNEL, reclaim_options); + batch_size, GFP_KERNEL, + reclaim_options, + swappiness == -1 ? NULL : &swappiness); if (!reclaimed && !nr_retries--) return -EAGAIN; diff --git a/mm/vmscan.c b/mm/vmscan.c index 91f99558650d..3d4c681c6d40 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -92,6 +92,11 @@ struct scan_control { unsigned long anon_cost; unsigned long file_cost; +#ifdef CONFIG_MEMCG + /* Swappiness value for proactive reclaim. Always use sc_swappiness()! */ + int *proactive_swappiness; +#endif + /* Can active folios be deactivated as part of reclaim? */ #define DEACTIVATE_ANON 1 #define DEACTIVATE_FILE 2 @@ -236,6 +241,13 @@ static bool writeback_throttling_sane(struct scan_control *sc) #endif return false; } + +static int sc_swappiness(struct scan_control *sc, struct mem_cgroup *memcg) +{ + if (sc->proactive && sc->proactive_swappiness) + return *sc->proactive_swappiness; + return mem_cgroup_swappiness(memcg); +} #else static bool cgroup_reclaim(struct scan_control *sc) { @@ -251,6 +263,11 @@ static bool writeback_throttling_sane(struct scan_control *sc) { return true; } + +static int sc_swappiness(struct scan_control *sc, struct mem_cgroup *memcg) +{ + return READ_ONCE(vm_swappiness); +} #endif static void set_task_reclaim_state(struct task_struct *task, @@ -2351,7 +2368,7 @@ static void get_scan_count(struct lruvec *lruvec, struct scan_control *sc, struct pglist_data *pgdat = lruvec_pgdat(lruvec); struct mem_cgroup *memcg = lruvec_memcg(lruvec); unsigned long anon_cost, file_cost, total_cost; - int swappiness = mem_cgroup_swappiness(memcg); + int swappiness = sc_swappiness(sc, memcg); u64 fraction[ANON_AND_FILE]; u64 denominator = 0; /* gcc */ enum scan_balance scan_balance; @@ -2632,7 +2649,7 @@ static int get_swappiness(struct lruvec *lruvec, struct scan_control *sc) mem_cgroup_get_nr_swap_pages(memcg) < MIN_LRU_BATCH) return 0; - return mem_cgroup_swappiness(memcg); + return sc_swappiness(sc, memcg); } static int get_nr_gens(struct lruvec *lruvec, int type) @@ -6549,12 +6566,14 @@ unsigned long mem_cgroup_shrink_node(struct mem_cgroup *memcg, unsigned long try_to_free_mem_cgroup_pages(struct mem_cgroup *memcg, unsigned long nr_pages, gfp_t gfp_mask, - unsigned int reclaim_options) + unsigned int reclaim_options, + int *swappiness) { unsigned long nr_reclaimed; unsigned int noreclaim_flag; struct scan_control sc = { .nr_to_reclaim = max(nr_pages, SWAP_CLUSTER_MAX), + .proactive_swappiness = swappiness, .gfp_mask = (current_gfp_context(gfp_mask) & GFP_RECLAIM_MASK) | (GFP_HIGHUSER_MOVABLE & ~GFP_RECLAIM_MASK), .reclaim_idx = MAX_NR_ZONES - 1,