This collects stats for shrinker calls and how much waste work we do within the lowmemorykiller. Signed-off-by: Peter Enderborg <peter.enderborg@xxxxxxxxxxxxxx> --- drivers/staging/android/Kconfig | 11 ++++ drivers/staging/android/Makefile | 1 + drivers/staging/android/lowmemorykiller.c | 9 ++- drivers/staging/android/lowmemorykiller_stats.c | 85 +++++++++++++++++++++++++ drivers/staging/android/lowmemorykiller_stats.h | 29 +++++++++ 5 files changed, 134 insertions(+), 1 deletion(-) create mode 100644 drivers/staging/android/lowmemorykiller_stats.c create mode 100644 drivers/staging/android/lowmemorykiller_stats.h diff --git a/drivers/staging/android/Kconfig b/drivers/staging/android/Kconfig index 6c00d6f..96e86c7 100644 --- a/drivers/staging/android/Kconfig +++ b/drivers/staging/android/Kconfig @@ -24,6 +24,17 @@ config ANDROID_LOW_MEMORY_KILLER scripts (/init.rc), and it defines priority values with minimum free memory size for each priority. +config ANDROID_LOW_MEMORY_KILLER_STATS + bool "Android Low Memory Killer: collect statistics" + depends on ANDROID_LOW_MEMORY_KILLER + default n + help + Create a file in /proc/lmkstats that includes + collected statistics about kills, scans and counts + and interaction with the shrinker. Its content + will be different depeding on lmk implementation used. + + source "drivers/staging/android/ion/Kconfig" endif # if ANDROID diff --git a/drivers/staging/android/Makefile b/drivers/staging/android/Makefile index 7ed1be7..d710eb2 100644 --- a/drivers/staging/android/Makefile +++ b/drivers/staging/android/Makefile @@ -4,3 +4,4 @@ obj-y += ion/ obj-$(CONFIG_ASHMEM) += ashmem.o obj-$(CONFIG_ANDROID_LOW_MEMORY_KILLER) += lowmemorykiller.o +obj-$(CONFIG_ANDROID_LOW_MEMORY_KILLER_STATS) += lowmemorykiller_stats.o diff --git a/drivers/staging/android/lowmemorykiller.c b/drivers/staging/android/lowmemorykiller.c index ec3b665..15c1b38 100644 --- a/drivers/staging/android/lowmemorykiller.c +++ b/drivers/staging/android/lowmemorykiller.c @@ -42,6 +42,7 @@ #include <linux/rcupdate.h> #include <linux/profile.h> #include <linux/notifier.h> +#include "lowmemorykiller_stats.h" static u32 lowmem_debug_level = 1; static short lowmem_adj[6] = { @@ -72,6 +73,7 @@ static unsigned long lowmem_deathpending_timeout; static unsigned long lowmem_count(struct shrinker *s, struct shrink_control *sc) { + lmk_inc_stats(LMK_COUNT); return global_node_page_state(NR_ACTIVE_ANON) + global_node_page_state(NR_ACTIVE_FILE) + global_node_page_state(NR_INACTIVE_ANON) + @@ -95,6 +97,7 @@ static unsigned long lowmem_scan(struct shrinker *s, struct shrink_control *sc) global_node_page_state(NR_SHMEM) - total_swapcache_pages(); + lmk_inc_stats(LMK_SCAN); if (lowmem_adj_size < array_size) array_size = lowmem_adj_size; if (lowmem_minfree_size < array_size) @@ -134,6 +137,7 @@ static unsigned long lowmem_scan(struct shrinker *s, struct shrink_control *sc) if (task_lmk_waiting(p) && time_before_eq(jiffies, lowmem_deathpending_timeout)) { task_unlock(p); + lmk_inc_stats(LMK_TIMEOUT); rcu_read_unlock(); return 0; } @@ -179,7 +183,9 @@ static unsigned long lowmem_scan(struct shrinker *s, struct shrink_control *sc) other_free * (long)(PAGE_SIZE / 1024)); lowmem_deathpending_timeout = jiffies + HZ; rem += selected_tasksize; - } + lmk_inc_stats(LMK_KILL); + } else + lmk_inc_stats(LMK_WASTE); lowmem_print(4, "lowmem_scan %lu, %x, return %lu\n", sc->nr_to_scan, sc->gfp_mask, rem); @@ -196,6 +202,7 @@ static struct shrinker lowmem_shrinker = { static int __init lowmem_init(void) { register_shrinker(&lowmem_shrinker); + init_procfs_lmk(); return 0; } device_initcall(lowmem_init); diff --git a/drivers/staging/android/lowmemorykiller_stats.c b/drivers/staging/android/lowmemorykiller_stats.c new file mode 100644 index 0000000..673691c --- /dev/null +++ b/drivers/staging/android/lowmemorykiller_stats.c @@ -0,0 +1,85 @@ +/* + * lowmemorykiller_stats + * + * Copyright (C) 2017 Sony Mobile Communications Inc. + * + * Author: Peter Enderborg <peter.enderborg@xxxxxxxxxxxxxx> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ +/* This code is bookkeeping of statistical information + * from lowmemorykiller and provide a node in proc "/proc/lmkstats". + */ + +#include <linux/proc_fs.h> +#include <linux/seq_file.h> +#include "lowmemorykiller_stats.h" + +struct lmk_stats { + atomic_long_t scans; /* counter as in shrinker scans */ + atomic_long_t kills; /* the number of sigkills sent */ + atomic_long_t waste; /* the numer of extensive calls that did + * not lead to anything + */ + atomic_long_t timeout; /* counter for shrinker calls that needed + * to be cancelled due to pending kills + */ + atomic_long_t count; /* number of shrinker count calls */ + atomic_long_t unknown; /* internal */ +} st; + +void lmk_inc_stats(int key) +{ + switch (key) { + case LMK_SCAN: + atomic_long_inc(&st.scans); + break; + case LMK_KILL: + atomic_long_inc(&st.kills); + break; + case LMK_WASTE: + atomic_long_inc(&st.waste); + break; + case LMK_TIMEOUT: + atomic_long_inc(&st.timeout); + break; + case LMK_COUNT: + atomic_long_inc(&st.count); + break; + default: + atomic_long_inc(&st.unknown); + break; + } +} + +static int lmk_proc_show(struct seq_file *m, void *v) +{ + seq_printf(m, "kill: %ld\n", atomic_long_read(&st.kills)); + seq_printf(m, "scan: %ld\n", atomic_long_read(&st.scans)); + seq_printf(m, "waste: %ld\n", atomic_long_read(&st.waste)); + seq_printf(m, "timeout: %ld\n", atomic_long_read(&st.timeout)); + seq_printf(m, "count: %ld\n", atomic_long_read(&st.count)); + seq_printf(m, "unknown: %ld (internal)\n", + atomic_long_read(&st.unknown)); + + return 0; +} + +static int lmk_proc_open(struct inode *inode, struct file *file) +{ + return single_open(file, lmk_proc_show, PDE_DATA(inode)); +} + +static const struct file_operations lmk_proc_fops = { + .open = lmk_proc_open, + .read = seq_read, + .release = single_release +}; + +int __init init_procfs_lmk(void) +{ + proc_create_data(LMK_PROCFS_NAME, 0444, NULL, &lmk_proc_fops, NULL); + return 0; +} diff --git a/drivers/staging/android/lowmemorykiller_stats.h b/drivers/staging/android/lowmemorykiller_stats.h new file mode 100644 index 0000000..abeb6924 --- /dev/null +++ b/drivers/staging/android/lowmemorykiller_stats.h @@ -0,0 +1,29 @@ +/* + * lowmemorykiller_stats interface + * + * Copyright (C) 2017 Sony Mobile Communications Inc. + * + * Author: Peter Enderborg <peter.enderborg@xxxxxxxxxxxxxx> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +enum lmk_kill_stats { + LMK_SCAN = 1, + LMK_KILL = 2, + LMK_WASTE = 3, + LMK_TIMEOUT = 4, + LMK_COUNT = 5 +}; + +#define LMK_PROCFS_NAME "lmkstats" + +#ifdef CONFIG_ANDROID_LOW_MEMORY_KILLER_STATS +void lmk_inc_stats(int key); +int __init init_procfs_lmk(void); +#else +static inline void lmk_inc_stats(int key) { return; }; +static inline int __init init_procfs_lmk(void) { return 0; }; +#endif -- 2.4.2 _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel