diff options
Diffstat (limited to 'linux/shrinker.c')
-rw-r--r-- | linux/shrinker.c | 140 |
1 files changed, 0 insertions, 140 deletions
diff --git a/linux/shrinker.c b/linux/shrinker.c deleted file mode 100644 index ca34ebc7..00000000 --- a/linux/shrinker.c +++ /dev/null @@ -1,140 +0,0 @@ - -#include <stdio.h> -#include <unistd.h> - -#include <linux/kthread.h> -#include <linux/list.h> -#include <linux/mm.h> -#include <linux/mutex.h> -#include <linux/shrinker.h> - -#include "tools-util.h" - -static LIST_HEAD(shrinker_list); -static DEFINE_MUTEX(shrinker_lock); - -void shrinker_free(struct shrinker *s) -{ - if (s->list.next) { - mutex_lock(&shrinker_lock); - list_del(&s->list); - mutex_unlock(&shrinker_lock); - } - free(s); -} - -struct shrinker *shrinker_alloc(unsigned int flags, const char *fmt, ...) -{ - return calloc(sizeof(struct shrinker), 1); -} - -int shrinker_register(struct shrinker *shrinker) -{ - mutex_lock(&shrinker_lock); - list_add_tail(&shrinker->list, &shrinker_list); - mutex_unlock(&shrinker_lock); - return 0; -} - -static void run_shrinkers_allocation_failed(gfp_t gfp_mask) -{ - struct shrinker *shrinker; - - mutex_lock(&shrinker_lock); - list_for_each_entry(shrinker, &shrinker_list, list) { - struct shrink_control sc = { .gfp_mask = gfp_mask, }; - - unsigned long have = shrinker->count_objects(shrinker, &sc); - - sc.nr_to_scan = have / 8; - - shrinker->scan_objects(shrinker, &sc); - } - mutex_unlock(&shrinker_lock); -} - -void run_shrinkers(gfp_t gfp_mask, bool allocation_failed) -{ - struct shrinker *shrinker; - struct sysinfo info; - s64 want_shrink; - - if (!(gfp_mask & GFP_KERNEL)) - return; - - /* Fast out if there are no shrinkers to run. */ - if (list_empty(&shrinker_list)) - return; - - if (allocation_failed) { - run_shrinkers_allocation_failed(gfp_mask); - return; - } - - si_meminfo(&info); - - /* Aim for 6% of physical RAM free without anything in swap */ - want_shrink = (info.totalram >> 4) - info.freeram - + info.totalswap - info.freeswap; - if (want_shrink <= 0) - return; - - mutex_lock(&shrinker_lock); - list_for_each_entry(shrinker, &shrinker_list, list) { - struct shrink_control sc = { - .gfp_mask = gfp_mask, - .nr_to_scan = want_shrink >> PAGE_SHIFT - }; - - shrinker->scan_objects(shrinker, &sc); - } - mutex_unlock(&shrinker_lock); -} - -static int shrinker_thread(void *arg) -{ - while (!kthread_should_stop()) { - struct timespec to; - int v; - - clock_gettime(CLOCK_MONOTONIC, &to); - to.tv_sec += 1; - __set_current_state(TASK_INTERRUPTIBLE); - errno = 0; - while ((v = READ_ONCE(current->state)) != TASK_RUNNING && - errno != ETIMEDOUT) - futex(¤t->state, FUTEX_WAIT_BITSET|FUTEX_PRIVATE_FLAG, - v, &to, NULL, (uint32_t)~0); - if (kthread_should_stop()) - break; - if (v != TASK_RUNNING) - __set_current_state(TASK_RUNNING); - run_shrinkers(GFP_KERNEL, false); - } - - return 0; -} - -struct task_struct *shrinker_task; - -__attribute__((constructor(103))) -static void shrinker_thread_init(void) -{ - shrinker_task = kthread_run(shrinker_thread, NULL, "shrinkers"); - BUG_ON(IS_ERR(shrinker_task)); -} - -#if 0 -/* - * We seem to be hitting a rare segfault when shutting down the shrinker thread. - * Disabling this is going to cause some harmless warnings about memory leaks: - */ -__attribute__((destructor(103))) -static void shrinker_thread_exit(void) -{ - int ret = kthread_stop(shrinker_task); - BUG_ON(ret); - - shrinker_task = NULL; -} -#endif |