Revision 7d638093d4b0e9ef15bd78f38f11f126e773cc14 authored by Vladimir Davydov on 10 June 2015, 18:14:46 UTC, committed by Linus Torvalds on 10 June 2015, 23:43:43 UTC
When trimming memcg consumption excess (see memory.high), we call try_to_free_mem_cgroup_pages without checking if we are allowed to sleep in the current context, which can result in a deadlock. Fix this. Fixes: 241994ed8649 ("mm: memcontrol: default hierarchy interface for memory") Signed-off-by: Vladimir Davydov <vdavydov@parallels.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Michal Hocko <mhocko@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1 parent 85bd839
interval_tree_test.c
#include <linux/module.h>
#include <linux/interval_tree.h>
#include <linux/random.h>
#include <asm/timex.h>
#define NODES 100
#define PERF_LOOPS 100000
#define SEARCHES 100
#define SEARCH_LOOPS 10000
static struct rb_root root = RB_ROOT;
static struct interval_tree_node nodes[NODES];
static u32 queries[SEARCHES];
static struct rnd_state rnd;
static inline unsigned long
search(unsigned long query, struct rb_root *root)
{
struct interval_tree_node *node;
unsigned long results = 0;
for (node = interval_tree_iter_first(root, query, query); node;
node = interval_tree_iter_next(node, query, query))
results++;
return results;
}
static void init(void)
{
int i;
for (i = 0; i < NODES; i++) {
u32 a = prandom_u32_state(&rnd);
u32 b = prandom_u32_state(&rnd);
if (a <= b) {
nodes[i].start = a;
nodes[i].last = b;
} else {
nodes[i].start = b;
nodes[i].last = a;
}
}
for (i = 0; i < SEARCHES; i++)
queries[i] = prandom_u32_state(&rnd);
}
static int interval_tree_test_init(void)
{
int i, j;
unsigned long results;
cycles_t time1, time2, time;
printk(KERN_ALERT "interval tree insert/remove");
prandom_seed_state(&rnd, 3141592653589793238ULL);
init();
time1 = get_cycles();
for (i = 0; i < PERF_LOOPS; i++) {
for (j = 0; j < NODES; j++)
interval_tree_insert(nodes + j, &root);
for (j = 0; j < NODES; j++)
interval_tree_remove(nodes + j, &root);
}
time2 = get_cycles();
time = time2 - time1;
time = div_u64(time, PERF_LOOPS);
printk(" -> %llu cycles\n", (unsigned long long)time);
printk(KERN_ALERT "interval tree search");
for (j = 0; j < NODES; j++)
interval_tree_insert(nodes + j, &root);
time1 = get_cycles();
results = 0;
for (i = 0; i < SEARCH_LOOPS; i++)
for (j = 0; j < SEARCHES; j++)
results += search(queries[j], &root);
time2 = get_cycles();
time = time2 - time1;
time = div_u64(time, SEARCH_LOOPS);
results = div_u64(results, SEARCH_LOOPS);
printk(" -> %llu cycles (%lu results)\n",
(unsigned long long)time, results);
return -EAGAIN; /* Fail will directly unload the module */
}
static void interval_tree_test_exit(void)
{
printk(KERN_ALERT "test exit\n");
}
module_init(interval_tree_test_init)
module_exit(interval_tree_test_exit)
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Michel Lespinasse");
MODULE_DESCRIPTION("Interval Tree test");
![swh spinner](/static/img/swh-spinner.gif)
Computing file changes ...