First step to clean up pbuf implementation: add pbuf_alloc_reference() to allocate pbufs referencing external payload; move member initialization to common function; simplify PBUF_POOL chain allocator

This commit is contained in:
goldsimon 2017-04-25 23:04:12 +02:00
parent e57552d401
commit eb269e61b5
2 changed files with 104 additions and 104 deletions

View File

@ -151,6 +151,20 @@ void eth_rx_irq()
volatile u8_t pbuf_free_ooseq_pending;
#define PBUF_POOL_IS_EMPTY() pbuf_pool_is_empty()
/* Initialize members of struct pbuf after allocation */
static void
pbuf_init_alloced_pbuf(struct pbuf *p, void* payload, u16_t tot_len, u16_t len, u8_t type)
{
p->next = NULL;
p->payload = payload;
p->tot_len = tot_len;
p->len = len;
p->type = type;
p->flags = 0;
p->ref = 1;
p->if_idx = NETIF_NO_INDEX;
}
/**
* Attempt to reclaim some memory from queued out-of-sequence TCP segments
* if we run out of pool pbufs. It's better to give priority to new packets
@ -248,11 +262,14 @@ pbuf_pool_is_empty(void)
struct pbuf *
pbuf_alloc(pbuf_layer layer, u16_t length, pbuf_type type)
{
struct pbuf *p, *q, *r;
struct pbuf *p;
u16_t offset;
s32_t rem_len; /* remaining length */
LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_TRACE, ("pbuf_alloc(length=%"U16_F")\n", length));
if ((type == PBUF_REF) || (type == PBUF_ROM)) {
return pbuf_alloc_reference(NULL, length, type);
}
/* determine header offset */
switch (layer) {
case PBUF_TRANSPORT:
@ -282,75 +299,42 @@ pbuf_alloc(pbuf_layer layer, u16_t length, pbuf_type type)
switch (type) {
case PBUF_POOL:
/* allocate head of pbuf chain into p */
p = (struct pbuf *)memp_malloc(MEMP_PBUF_POOL);
LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_TRACE, ("pbuf_alloc: allocated pbuf %p\n", (void *)p));
if (p == NULL) {
PBUF_POOL_IS_EMPTY();
return NULL;
}
p->type = type;
p->next = NULL;
p->if_idx = NETIF_NO_INDEX;
/* make the payload pointer point 'offset' bytes into pbuf data memory */
p->payload = LWIP_MEM_ALIGN((void *)((u8_t *)p + (SIZEOF_STRUCT_PBUF + offset)));
LWIP_ASSERT("pbuf_alloc: pbuf p->payload properly aligned",
((mem_ptr_t)p->payload % MEM_ALIGNMENT) == 0);
/* the total length of the pbuf chain is the requested size */
p->tot_len = length;
/* set the length of the first pbuf in the chain */
p->len = LWIP_MIN(length, PBUF_POOL_BUFSIZE_ALIGNED - LWIP_MEM_ALIGN_SIZE(offset));
LWIP_ASSERT("check p->payload + p->len does not overflow pbuf",
((u8_t*)p->payload + p->len <=
(u8_t*)p + SIZEOF_STRUCT_PBUF + PBUF_POOL_BUFSIZE_ALIGNED));
LWIP_ASSERT("PBUF_POOL_BUFSIZE must be bigger than MEM_ALIGNMENT",
(PBUF_POOL_BUFSIZE_ALIGNED - LWIP_MEM_ALIGN_SIZE(offset)) > 0 );
/* set reference count (needed here in case we fail) */
p->ref = 1;
/* now allocate the tail of the pbuf chain */
/* remember first pbuf for linkage in next iteration */
r = p;
/* remaining length to be allocated */
rem_len = length - p->len;
/* any remaining pbufs to be allocated? */
while (rem_len > 0) {
q = (struct pbuf *)memp_malloc(MEMP_PBUF_POOL);
if (q == NULL) {
PBUF_POOL_IS_EMPTY();
/* free chain so far allocated */
pbuf_free(p);
/* bail out unsuccessfully */
return NULL;
{
struct pbuf *q, *last;
u16_t rem_len; /* remaining length */
p = NULL;
last = NULL;
rem_len = length;
while (rem_len > 0) {
q = (struct pbuf *)memp_malloc(MEMP_PBUF_POOL);
if (q == NULL) {
PBUF_POOL_IS_EMPTY();
/* free chain so far allocated */
if (p) {
pbuf_free(p);
}
/* bail out unsuccessfully */
return NULL;
}
pbuf_init_alloced_pbuf(q, LWIP_MEM_ALIGN((void *)((u8_t *)q + SIZEOF_STRUCT_PBUF + offset)),
rem_len, LWIP_MIN(rem_len, PBUF_POOL_BUFSIZE_ALIGNED - LWIP_MEM_ALIGN_SIZE(offset)), type);
LWIP_ASSERT("pbuf_alloc: pbuf q->payload properly aligned",
((mem_ptr_t)q->payload % MEM_ALIGNMENT) == 0);
LWIP_ASSERT("PBUF_POOL_BUFSIZE must be bigger than MEM_ALIGNMENT",
(PBUF_POOL_BUFSIZE_ALIGNED - LWIP_MEM_ALIGN_SIZE(offset)) > 0 );
if (p == NULL) {
/* allocated head of pbuf chain (into p) */
p = q;
} else {
/* make previous pbuf point to this pbuf */
last->next = q;
}
last = q;
rem_len -= q->len;
offset = 0;
}
q->type = type;
q->flags = 0;
q->next = NULL;
/* make previous pbuf point to this pbuf */
r->next = q;
/* set total length of this pbuf and next in chain */
LWIP_ASSERT("rem_len < max_u16_t", rem_len < 0xffff);
q->tot_len = (u16_t)rem_len;
/* this pbuf length is pool size, unless smaller sized tail */
q->len = LWIP_MIN((u16_t)rem_len, PBUF_POOL_BUFSIZE_ALIGNED);
q->payload = (void *)((u8_t *)q + SIZEOF_STRUCT_PBUF);
LWIP_ASSERT("pbuf_alloc: pbuf q->payload properly aligned",
((mem_ptr_t)q->payload % MEM_ALIGNMENT) == 0);
LWIP_ASSERT("check p->payload + p->len does not overflow pbuf",
((u8_t*)p->payload + p->len <=
(u8_t*)p + SIZEOF_STRUCT_PBUF + PBUF_POOL_BUFSIZE_ALIGNED));
q->ref = 1;
/* calculate remaining length to be allocated */
rem_len -= q->len;
/* remember this pbuf for linkage in next iteration */
r = q;
break;
}
/* end of chain */
/*r->next = NULL;*/
break;
case PBUF_RAM:
{
mem_size_t alloc_len = LWIP_MEM_ALIGN_SIZE(SIZEOF_STRUCT_PBUF + offset) + LWIP_MEM_ALIGN_SIZE(length);
@ -362,50 +346,65 @@ pbuf_alloc(pbuf_layer layer, u16_t length, pbuf_type type)
/* If pbuf is to be allocated in RAM, allocate memory for it. */
p = (struct pbuf*)mem_malloc(alloc_len);
if (p == NULL) {
return NULL;
}
pbuf_init_alloced_pbuf(p, LWIP_MEM_ALIGN((void *)((u8_t *)p + SIZEOF_STRUCT_PBUF + offset)),
length, length, type);
LWIP_ASSERT("pbuf_alloc: pbuf->payload properly aligned",
((mem_ptr_t)p->payload % MEM_ALIGNMENT) == 0);
break;
}
if (p == NULL) {
return NULL;
}
/* Set up internal structure of the pbuf. */
p->payload = LWIP_MEM_ALIGN((void *)((u8_t *)p + SIZEOF_STRUCT_PBUF + offset));
p->len = p->tot_len = length;
p->next = NULL;
p->type = type;
LWIP_ASSERT("pbuf_alloc: pbuf->payload properly aligned",
((mem_ptr_t)p->payload % MEM_ALIGNMENT) == 0);
break;
/* pbuf references existing (non-volatile static constant) ROM payload? */
case PBUF_ROM:
/* pbuf references existing (externally allocated) RAM payload? */
case PBUF_REF:
/* only allocate memory for the pbuf structure */
p = (struct pbuf *)memp_malloc(MEMP_PBUF);
if (p == NULL) {
LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_LEVEL_SERIOUS,
("pbuf_alloc: Could not allocate MEMP_PBUF for PBUF_%s.\n",
(type == PBUF_ROM) ? "ROM" : "REF"));
return NULL;
}
/* caller must set this field properly, afterwards */
p->payload = NULL;
p->len = p->tot_len = length;
p->next = NULL;
p->type = type;
break;
default:
LWIP_ASSERT("pbuf_alloc: erroneous type", 0);
return NULL;
}
/* set reference count */
p->ref = 1;
/* set flags */
p->flags = 0;
LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_TRACE, ("pbuf_alloc(length=%"U16_F") == %p\n", length, (void *)p));
return p;
}
/**
* @ingroup pbuf
* Allocates a pbuf for referenced data.
* Referenced data can be volatile (PBUF_REF) or long-lived (PBUF_ROM).
*
* The actual memory allocated for the pbuf is determined by the
* layer at which the pbuf is allocated and the requested size
* (from the size parameter).
*
* @param payload referenced payload
* @param length size of the pbuf's payload
* @param type this parameter decides how and where the pbuf
* should be allocated as follows:
*
* - PBUF_ROM: It is assumed that the memory used is really
* similar to ROM in that it is immutable and will not be
* changed. Memory which is dynamic should generally not
* be attached to PBUF_ROM pbufs. Use PBUF_REF instead.
* - PBUF_REF: It is assumed that the pbuf is only
* being used in a single thread. If the pbuf gets queued,
* then pbuf_take should be called to copy the buffer.
*
* @return the allocated pbuf.
*/
struct pbuf *
pbuf_alloc_reference(void *payload, u16_t length, pbuf_type type)
{
struct pbuf *p;
LWIP_ASSERT("invalid pbuf_type", (type == PBUF_REF) || (type == PBUF_ROM));
/* only allocate memory for the pbuf structure */
p = (struct pbuf *)memp_malloc(MEMP_PBUF);
if (p == NULL) {
LWIP_DEBUGF(PBUF_DEBUG | LWIP_DBG_LEVEL_SERIOUS,
("pbuf_alloc_reference: Could not allocate MEMP_PBUF for PBUF_%s.\n",
(type == PBUF_ROM) ? "ROM" : "REF"));
return NULL;
}
pbuf_init_alloced_pbuf(p, payload, length, length, type);
return p;
}
#if LWIP_SUPPORT_CUSTOM_PBUF
/**
* @ingroup pbuf

View File

@ -240,6 +240,7 @@ void pbuf_free_ooseq(void);
#define pbuf_init()
struct pbuf *pbuf_alloc(pbuf_layer l, u16_t length, pbuf_type type);
struct pbuf *pbuf_alloc_reference(void *payload, u16_t length, pbuf_type type);
#if LWIP_SUPPORT_CUSTOM_PBUF
struct pbuf *pbuf_alloced_custom(pbuf_layer l, u16_t length, pbuf_type type,
struct pbuf_custom *p, void *payload_mem,