kmem_cache_alloc_bulk() test

bulk_alloc.c

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/string.h>

MODULE_DESCRIPTION("bult test module");
MODULE_AUTHOR("masami256");
MODULE_LICENSE("GFP");

#define BULK_ALLOC_TEST_COUNT 100
#define BULK_ALLOC_TEST_ARRAY_SIZE 16

static int test_num;
module_param(test_num, int, 0);
MODULE_PARM_DESC(test_num, "Test number");

static char *test_name = "bulk";
module_param(test_name, charp, 0000);
MODULE_PARM_DESC(test_type, "Test name");

struct bulk_cache {
	int n;
	char msg[8];
};

static struct kmem_cache *bulk_cachep;

static inline u64 bulk_alloc_test_total_clock(u64 start, u64 end)
{
	return end - start;
}

static void bulk_alloc_test_bulk_alloc(void)
{
	struct bulk_cache *p[BULK_ALLOC_TEST_ARRAY_SIZE];
	bool ret;
	u64 start, end;

	rdtscll(start);
	ret = kmem_cache_alloc_bulk(bulk_cachep, GFP_KERNEL, BULK_ALLOC_TEST_ARRAY_SIZE, (void **) &p);
	if (!ret) {
		pr_warn("%s:%d: faild to allocate memory\n", __func__, __LINE__);
		return ;
	} 
	rdtscll(end);

	pr_info("bulk_test: test %d: kmem_cache_alloc_bulk() %lld\n", test_num, bulk_alloc_test_total_clock(start, end));

	kmem_cache_free_bulk(bulk_cachep, BULK_ALLOC_TEST_ARRAY_SIZE, (void **) &p);
}

static void bulk_alloc_test_slab_alloc(void)
{
	int i, j;
	struct bulk_cache *p[BULK_ALLOC_TEST_ARRAY_SIZE];
	u64 start, end;

	rdtscll(start);
	for (i = 0; i < BULK_ALLOC_TEST_ARRAY_SIZE; i++) {
		p[i] = kmem_cache_alloc(bulk_cachep, GFP_KERNEL);
		if (!p[i]) {
			pr_warn("%s:%d: faild to allocate memory\n", __func__, __LINE__);
			goto out;
		}
	}
	rdtscll(end);

	pr_info("bulk_test: test %d: kmem_cache_alloc() %lld\n", test_num, bulk_alloc_test_total_clock(start, end));
out:
	for (j = 0; j < i; j++) 
		kmem_cache_free(bulk_cachep, p[j]);

}
static int bulk_alloc_init(void)
{
	bulk_cachep = KMEM_CACHE(bulk_cache, SLAB_PANIC);
	pr_info("cache created: 0x%p\n", bulk_cachep);

	if (!strcmp(test_name, "bulk"))
		bulk_alloc_test_bulk_alloc();
	else
		bulk_alloc_test_slab_alloc();

	return 0;

}

static void bulk_alloc_cleanup(void)
{
	kmem_cache_destroy(bulk_cachep);
	pr_info("cache freed\n");
}

module_init(bulk_alloc_init);
module_exit(bulk_alloc_cleanup);

Makefile

KERNDIR := /lib/modules/`uname -r`/build
BUILD_DIR := $(shell pwd)
VERBOSE = 0

obj-m := bulk_alloc.o
smallmod-objs := bulk_alloc.o

all:
	make -C $(KERNDIR) SUBDIRS=$(BUILD_DIR) KBUILD_VERBOSE=$(VERBOSE) modules

clean:
	rm -f *.o
	rm -f *.ko
	rm -f *.mod.c
	rm -f *~

run_test.sh

#!/bin/bash

test_name="bulk"

if [ $# -eq 1 ]; then
    test_name=$1
fi

for ((i=0; i<100; i++));
do
    echo "run test ${i}"
    insmod ./bulk_alloc.ko test_num=${i} test_name=${test_name}
    rmmod bulk_alloc
done

dmesg | grep bulk_test