mirror of
https://gitlab.nic.cz/labs/bird.git
synced 2024-11-08 20:28:43 +00:00
a95141111c
The original algorithm was suffering from an ABA race condition: A: fp = page_stack B: completely allocates the same page and writes into it some data A: unsuspecting, loads (invalid) next = fp->next B: finishes working with the page and returns it back to page_stack A: compare-exchange page_stack: fp => next succeeds and writes garbage to page_stack Fixed this by using an implicit spinlock in hot page allocator.
75 lines
1.4 KiB
C
75 lines
1.4 KiB
C
/*
|
|
* BIRD -- Allocator Tests
|
|
*
|
|
* (c) 2023 CZ.NIC z.s.p.o.
|
|
* (c) 2023 Maria Matejka <mq@jmq.cz>
|
|
*
|
|
* Can be freely distributed and used under the terms of the GNU GPL.
|
|
*/
|
|
|
|
#include "test/birdtest.h"
|
|
#include "test/bt-utils.h"
|
|
#include "lib/resource.h"
|
|
|
|
#include <unistd.h>
|
|
#include <pthread.h>
|
|
|
|
#define ALLOC_AND_TREE_LIMIT (1 << 14)
|
|
|
|
static void *
|
|
alloc_and_free_main(void *data UNUSED)
|
|
{
|
|
#define BLOCK_SIZE 32
|
|
void *block[BLOCK_SIZE];
|
|
|
|
for (int i=0; i<ALLOC_AND_TREE_LIMIT; i++)
|
|
{
|
|
for (int b=0; b<BLOCK_SIZE; b++)
|
|
{
|
|
block[b] = alloc_page();
|
|
ASSERT_DIE(PAGE_HEAD(block[b]) == block[b]);
|
|
memset(block[b], 0x42, page_size);
|
|
}
|
|
|
|
for (int b=0; b<BLOCK_SIZE; b++)
|
|
{
|
|
free_page(block[b]);
|
|
block[b] = alloc_page();
|
|
ASSERT_DIE(PAGE_HEAD(block[b]) == block[b]);
|
|
memset(block[b], 0x53, page_size);
|
|
}
|
|
|
|
for (int b=0; b<BLOCK_SIZE; b++)
|
|
free_page(block[b]);
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
|
|
static int
|
|
t_alloc_and_free(void)
|
|
{
|
|
#define THR_N 16
|
|
pthread_t tid[THR_N];
|
|
|
|
for (int i=0; i<THR_N; i++)
|
|
{
|
|
pthread_create(&tid[i], NULL, alloc_and_free_main, NULL);
|
|
usleep(50 * i);
|
|
}
|
|
|
|
for (int i=0; i<THR_N; i++)
|
|
pthread_join(tid[i], NULL);
|
|
|
|
return 1;
|
|
}
|
|
|
|
int main(int argc, char **argv)
|
|
{
|
|
bt_init(argc, argv);
|
|
|
|
bt_test_suite(t_alloc_and_free, "Testing parallel allocations and free");
|
|
|
|
return bt_exit_value();
|
|
}
|