numam-dpdk/lib/librte_eal/bsdapp/contigmem/contigmem.c
Jim Harris 82f9318055 contigmem: zero all pages during mmap
On Linux, all huge pages are zeroed by the kernel before
first access by the DPDK application.  But on FreeBSD,
the contigmem driver would only zero the contiguous
memory regions during initial driver load.

DPDK commit b78c91751 eliminated the explicit memset()
operation for rte_zmalloc(), which was OK on Linux
because the kernel zeroes the pages during app start,
but this broke FreeBSD when restarting app.
So this patch explicitly zeroes the pages before they are mmap'd,
to ensure equivalent behavior to Linux.

Fixes: b78c917511 ("mem: do not zero out memory on zmalloc")

Reported-by: Daniel Verkamp <daniel.verkamp@intel.com>
Signed-off-by: Jim Harris <james.r.harris@intel.com>
Tested-by: Daniel Verkamp <daniel.verkamp@intel.com>
Acked-by: Sergio Gonzalez Monroy <sergio.gonzalez.monroy@intel.com>
2016-08-22 22:59:05 +02:00

237 lines
6.8 KiB
C

/*-
* BSD LICENSE
*
* Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* * Neither the name of Intel Corporation nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/bio.h>
#include <sys/bus.h>
#include <sys/conf.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/module.h>
#include <sys/proc.h>
#include <sys/rwlock.h>
#include <sys/systm.h>
#include <sys/sysctl.h>
#include <machine/bus.h>
#include <vm/vm.h>
#include <vm/pmap.h>
#include <vm/vm_object.h>
#include <vm/vm_page.h>
#include <vm/vm_pager.h>
static int contigmem_load(void);
static int contigmem_unload(void);
static int contigmem_physaddr(SYSCTL_HANDLER_ARGS);
static d_mmap_t contigmem_mmap;
static d_mmap_single_t contigmem_mmap_single;
static d_open_t contigmem_open;
static int contigmem_num_buffers = RTE_CONTIGMEM_DEFAULT_NUM_BUFS;
static int64_t contigmem_buffer_size = RTE_CONTIGMEM_DEFAULT_BUF_SIZE;
static eventhandler_tag contigmem_eh_tag;
static void *contigmem_buffers[RTE_CONTIGMEM_MAX_NUM_BUFS];
static struct cdev *contigmem_cdev = NULL;
TUNABLE_INT("hw.contigmem.num_buffers", &contigmem_num_buffers);
TUNABLE_QUAD("hw.contigmem.buffer_size", &contigmem_buffer_size);
static SYSCTL_NODE(_hw, OID_AUTO, contigmem, CTLFLAG_RD, 0, "contigmem");
SYSCTL_INT(_hw_contigmem, OID_AUTO, num_buffers, CTLFLAG_RD,
&contigmem_num_buffers, 0, "Number of contigmem buffers allocated");
SYSCTL_QUAD(_hw_contigmem, OID_AUTO, buffer_size, CTLFLAG_RD,
&contigmem_buffer_size, 0, "Size of each contiguous buffer");
static SYSCTL_NODE(_hw_contigmem, OID_AUTO, physaddr, CTLFLAG_RD, 0,
"physaddr");
MALLOC_DEFINE(M_CONTIGMEM, "contigmem", "contigmem(4) allocations");
static int contigmem_modevent(module_t mod, int type, void *arg)
{
int error = 0;
switch (type) {
case MOD_LOAD:
error = contigmem_load();
break;
case MOD_UNLOAD:
error = contigmem_unload();
break;
default:
break;
}
return error;
}
moduledata_t contigmem_mod = {
"contigmem",
(modeventhand_t)contigmem_modevent,
0
};
DECLARE_MODULE(contigmem, contigmem_mod, SI_SUB_DRIVERS, SI_ORDER_ANY);
MODULE_VERSION(contigmem, 1);
static struct cdevsw contigmem_ops = {
.d_name = "contigmem",
.d_version = D_VERSION,
.d_mmap = contigmem_mmap,
.d_mmap_single = contigmem_mmap_single,
.d_open = contigmem_open,
};
static int
contigmem_load()
{
char index_string[8], description[32];
int i;
if (contigmem_num_buffers > RTE_CONTIGMEM_MAX_NUM_BUFS) {
printf("%d buffers requested is greater than %d allowed\n",
contigmem_num_buffers, RTE_CONTIGMEM_MAX_NUM_BUFS);
return EINVAL;
}
if (contigmem_buffer_size < PAGE_SIZE ||
(contigmem_buffer_size & (contigmem_buffer_size - 1)) != 0) {
printf("buffer size 0x%lx is not greater than PAGE_SIZE and "
"power of two\n", contigmem_buffer_size);
return EINVAL;
}
for (i = 0; i < contigmem_num_buffers; i++) {
contigmem_buffers[i] =
contigmalloc(contigmem_buffer_size, M_CONTIGMEM, M_ZERO, 0,
BUS_SPACE_MAXADDR, contigmem_buffer_size, 0);
if (contigmem_buffers[i] == NULL) {
printf("contigmalloc failed for buffer %d\n", i);
return ENOMEM;
}
printf("%2u: virt=%p phys=%p\n", i, contigmem_buffers[i],
(void *)pmap_kextract((vm_offset_t)contigmem_buffers[i]));
snprintf(index_string, sizeof(index_string), "%d", i);
snprintf(description, sizeof(description),
"phys addr for buffer %d", i);
SYSCTL_ADD_PROC(NULL,
&SYSCTL_NODE_CHILDREN(_hw_contigmem, physaddr), OID_AUTO,
index_string, CTLTYPE_U64 | CTLFLAG_RD,
(void *)(uintptr_t)i, 0, contigmem_physaddr, "LU",
description);
}
contigmem_cdev = make_dev_credf(0, &contigmem_ops, 0, NULL, UID_ROOT,
GID_WHEEL, 0600, "contigmem");
return 0;
}
static int
contigmem_unload()
{
int i;
if (contigmem_cdev != NULL)
destroy_dev(contigmem_cdev);
if (contigmem_eh_tag != NULL)
EVENTHANDLER_DEREGISTER(process_exit, contigmem_eh_tag);
for (i = 0; i < RTE_CONTIGMEM_MAX_NUM_BUFS; i++)
if (contigmem_buffers[i] != NULL)
contigfree(contigmem_buffers[i], contigmem_buffer_size,
M_CONTIGMEM);
return 0;
}
static int
contigmem_physaddr(SYSCTL_HANDLER_ARGS)
{
uint64_t physaddr;
int index = (int)(uintptr_t)arg1;
physaddr = (uint64_t)vtophys(contigmem_buffers[index]);
return sysctl_handle_64(oidp, &physaddr, 0, req);
}
static int
contigmem_open(struct cdev *cdev, int fflags, int devtype,
struct thread *td)
{
return 0;
}
static int
contigmem_mmap(struct cdev *cdev, vm_ooffset_t offset, vm_paddr_t *paddr,
int prot, vm_memattr_t *memattr)
{
*paddr = offset;
return 0;
}
static int
contigmem_mmap_single(struct cdev *cdev, vm_ooffset_t *offset, vm_size_t size,
struct vm_object **obj, int nprot)
{
uint64_t buffer_index;
/*
* The buffer index is encoded in the offset. Divide the offset by
* PAGE_SIZE to get the index of the buffer requested by the user
* app.
*/
buffer_index = *offset / PAGE_SIZE;
if (buffer_index >= contigmem_num_buffers)
return EINVAL;
memset(contigmem_buffers[buffer_index], 0, contigmem_buffer_size);
*offset = (vm_ooffset_t)vtophys(contigmem_buffers[buffer_index]);
*obj = vm_pager_allocate(OBJT_DEVICE, cdev, size, nprot, *offset,
curthread->td_ucred);
return 0;
}