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Lots of clearing up comments and use of new debugging features.

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This commit is contained in:
likewise 2003-03-24 15:15:18 +00:00
parent cea002a088
commit 80b961df60
1 changed files with 84 additions and 72 deletions
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156
src/core/pbuf.c
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@ -266,7 +266,7 @@ pbuf_alloc(pbuf_layer l, u16_t size, pbuf_flag flag)
rsize = size - p->len;
while(rsize > 0) {
q = pbuf_pool_alloc();
if(q == NULL) {
if (q == NULL) {
DEBUGF(PBUF_DEBUG | 2, ("pbuf_alloc: Out of pbufs in pool.\n"));
#ifdef PBUF_STATS
++lwip_stats.pbuf.err;
@ -281,9 +281,9 @@ pbuf_alloc(pbuf_layer l, u16_t size, pbuf_flag flag)
q->payload = (void *)((u8_t *)q + sizeof(struct pbuf));
r = q;
q->ref = 1;
/*q = q->next; DJH: Appears to be an unnecessary statement*/
rsize -= PBUF_POOL_BUFSIZE;
}
/* end of chain */
r->next = NULL;
LWIP_ASSERT("pbuf_alloc: pbuf->payload properly aligned",
@ -304,14 +304,17 @@ pbuf_alloc(pbuf_layer l, u16_t size, pbuf_flag flag)
LWIP_ASSERT("pbuf_alloc: pbuf->payload properly aligned",
((u32_t)p->payload % MEM_ALIGNMENT) == 0);
break;
case PBUF_ROM:
case PBUF_REF:
/* If the pbuf should point to ROM, we only need to allocate
memory for the pbuf structure. */
/* pbuf references existing ROM payload? */
case PBUF_ROM:
/* pbuf references existing (externally allocated) RAM payload? */
case PBUF_REF:
/* only allocate memory for the pbuf structure */
p = memp_mallocp(MEMP_PBUF);
if(p == NULL) {
DEBUGF(PBUF_DEBUG | DBG_TRACE | 2, ("pbuf_alloc: Could not allocate MEMP_PBUF for PBUF_REF.\n"));
return NULL;
}
/* caller must set this field properly, afterwards */
p->payload = NULL;
p->len = p->tot_len = size;
p->next = NULL;
@ -535,70 +538,71 @@ pbuf_free(struct pbuf *p)
struct pbuf *q;
u8_t count = 0;
SYS_ARCH_DECL_PROTECT(old_level);
if(p == NULL) {
return 0;
}
PERF_START;
LWIP_ASSERT("pbuf_free: sane flags", p->flags == PBUF_FLAG_POOL ||
p->flags == PBUF_FLAG_ROM ||
p->flags == PBUF_FLAG_RAM ||
p->flags == PBUF_FLAG_REF );
p->flags == PBUF_FLAG_ROM ||
p->flags == PBUF_FLAG_RAM ||
p->flags == PBUF_FLAG_REF );
/* Since decrementing ref cannot be guarranteed to be a single machine operation
we must protect it. Also, the later test of ref must be protected.
we must protect it. Also, the later test of ref must be protected.
*/
SYS_ARCH_PROTECT(old_level);
/* Decrement reference count. */
/* Decrement reference count. */
for (q = p; q != NULL; q = q->next) {
LWIP_ASSERT("pbuf_free: q->ref == 0", q->ref > 0);
LWIP_ASSERT("pbuf_free: q->ref > 0", q->ref > 0);
q->ref--;
}
}
/*q = NULL; DJH: Unnecessary statement*/
/* If reference count == 0, actually deallocate pbuf. */
if(p->ref == 0) {
SYS_ARCH_UNPROTECT(old_level);
while(p != NULL) {
/* Check if this is a pbuf from the pool. */
if(p->flags == PBUF_FLAG_POOL) {
p->len = p->tot_len = PBUF_POOL_BUFSIZE;
p->payload = (void *)((u8_t *)p + sizeof(struct pbuf));
q = p->next;
PBUF_POOL_FREE(p);
} else {
if(p->flags == PBUF_FLAG_ROM || p->flags == PBUF_FLAG_REF) {
q = p->next;
memp_freep(MEMP_PBUF, p);
} else {
q = p->next;
mem_free(p);
}
}
p = q;
/* Only free the next one in a chain if it's reference count is 0.
This allows buffer chains to have multiple headers pointing to them. */
if (p)
{
p->ref--;
if (p->ref > 0)
break;
}
++count;
while(p != NULL) {
/* this is a pbuf from the pool? */
if(p->flags == PBUF_FLAG_POOL) {
p->len = p->tot_len = PBUF_POOL_BUFSIZE;
p->payload = (void *)((u8_t *)p + sizeof(struct pbuf));
q = p->next;
PBUF_POOL_FREE(p);
/* not a pbuf from the pool */
}
pbuf_refresh();
}
else {
if(p->flags == PBUF_FLAG_ROM || p->flags == PBUF_FLAG_REF) {
q = p->next;
memp_freep(MEMP_PBUF, p);
}
else {
q = p->next;
mem_free(p);
}
}
p = q;
/* Only free the next one in a chain if it's reference count is 0.
This allows buffer chains to have multiple headers pointing to them. */
if (p)
{
p->ref--;
if (p->ref > 0)
break;
}
++count;
}
pbuf_refresh();
}
else
SYS_ARCH_UNPROTECT(old_level);
PERF_STOP("pbuf_free");
return count;
}
/*-----------------------------------------------------------------------------------*/
@ -699,47 +703,54 @@ pbuf_dechain(struct pbuf *p)
return q;
}
/** Replace any pbufs of type PBUF_FLAG_REF with PBUF_POOL buffers.
Go through pbuf chain and replace any PBUF_REF buffers with PBUF_POOL
buffers. This is generally done for buffer chains which need to be queued
in some way (either on an output queue or on the arp queue). All pbufs
replaced will be freed immediately.
@param f Head of pbuf chain to process
@return Pointer to new head of pbuf chain.
*/
/**
*
* Replace any PBUF_REF pbufs of a chain into PBUF_POOL/RAM buffers.
*
* Go through pbuf chain and replace any PBUF_REF buffers with PBUF_POOL
* (or PBUF_RAM) buffers.
*
* Used to queue packets on behalf of the lwIP stack, such as ARP based
* queueing.
*
* @param f Head of pbuf chain to process
*
* @return Pointer to new head of pbuf chain.
*/
struct pbuf *
pbuf_unref(struct pbuf *f)
{
struct pbuf *p, *prev, *top;
DEBUGF(PBUF_DEBUG | DBG_TRACE, ("pbuf_unref: %p\n", (void*)f));
LWIP_ASSERT("pbuf_unref: f != NULL", f != NULL);
DEBUGF(PBUF_DEBUG | DBG_TRACE | 3, ("pbuf_unref(%p)\n", (void*)f));
prev = NULL;
p = f;
top = f;
/* iterate through pbuf chain */
do
{
/* pbuf is of type PBUF_REF? */
if (p->flags == PBUF_FLAG_REF)
{
/* the replacement pbuf */
struct pbuf *q;
q = NULL;
DEBUGF(PBUF_DEBUG | DBG_TRACE, ("pbuf_unref: encountered PBUF_REF %p\n", (void *)p));
/* allocate a pbuf (w/ payload) fully in RAM */
/* PBUF_POOL buffers are faster if we can use them */
if (p->len <= PBUF_POOL_BUFSIZE) {
q = pbuf_alloc(PBUF_RAW, p->len, PBUF_POOL);
if (q == NULL) DEBUGF(PBUF_DEBUG | DBG_TRACE, ("pbuf_unref: Could not allocate PBUF_RAW\n"));
if (q == NULL) DEBUGF(PBUF_DEBUG | DBG_TRACE | 2, ("pbuf_unref: Could not allocate PBUF_RAW\n"));
}
/* no (large enough) PBUF_POOL was available? retry with PBUF_RAM */
if (q == NULL) {
q = pbuf_alloc(PBUF_RAW, p->len, PBUF_RAM);
if (q == NULL) DEBUGF(PBUF_DEBUG | DBG_TRACE, ("pbuf_unref: Could not allocate PBUF_POOL\n"));
if (q == NULL) DEBUGF(PBUF_DEBUG | DBG_TRACE | 2, ("pbuf_unref: Could not allocate PBUF_POOL\n"));
}
if (q != NULL)
{
/* copy pbuf struct */
/* copy successor */
q->next = p->next;
if (prev != NULL)
/* Break chain and insert new pbuf instead */
@ -751,26 +762,27 @@ pbuf_unref(struct pbuf *f)
memcpy(q->payload, p->payload, p->len);
q->tot_len = p->tot_len;
q->len = p->len;
/* Don't copy ref, since someone else might be using the old buffer */
/* de-allocate PBUF_REF */
/* pbuf is not freed because it is assumed that some upper level
program has a direct pointer to this pbuf and will free it. */
/* do not copy ref, since someone else might be using the old buffer */
/* pbuf is not freed, as this is the responsibility of the application */
DEBUGF(PBUF_DEBUG, ("pbuf_unref: replaced PBUF_REF %p with %q\n", (void *)p, (void *)q));
p = q;
DEBUGF(PBUF_DEBUG, ("pbuf_unref: succesful %p \n", (void *)p));
}
else
{
/* deallocate chain */
pbuf_free(top);
DEBUGF(PBUF_DEBUG | 2, ("pbuf_unref: failed\n"));
DEBUGF(PBUF_DEBUG | 2, ("pbuf_unref: failed to allocate replacement pbuf for %p\n", (void *)p));
return NULL;
}
}
else {
DEBUGF(PBUF_DEBUG | DBG_TRACE | 1, ("pbuf_unref: not PBUF_REF"));
}
prev = p;
p = p->next;
} while (p);
DEBUGF(PBUF_DEBUG | DBG_TRACE | 1, ("pbuf_unref: end of chain reached."));
return top;
}