MINOR: cache: Larger HTTP objects caching.
This patch makes the capable of storing HTTP objects larger than a buffer.
It makes usage of the "block by block shared object allocation" new shctx API.
A new pointer to struct shared_block has been added to the cache applet
context to memorize the next block to be used by the HTTP cache I/O handler
http_cache_io_handler() to emit the data. Another member, named "sent" memorize
the number of bytes already sent by this handler. So, to send an object from cache,
http_cache_io_handler() must be called until "sent" counter reaches the size
of this object.
diff --git a/src/cache.c b/src/cache.c
index b549537..a198b40 100644
--- a/src/cache.c
+++ b/src/cache.c
@@ -182,15 +182,30 @@
return 1;
}
+static inline void disable_cache_entry(struct cache_st *st,
+ struct filter *filter, struct shared_context *shctx)
+{
+ struct cache_entry *object;
+
+ object = (struct cache_entry *)st->first_block->data;
+ filter->ctx = NULL; /* disable cache */
+ shctx_lock(shctx);
+ shctx_row_dec_hot(shctx, st->first_block);
+ object->eb.key = 0;
+ shctx_unlock(shctx);
+ pool_free(pool_head_cache_st, st);
+}
+
static int
cache_store_http_forward_data(struct stream *s, struct filter *filter,
struct http_msg *msg, unsigned int len)
{
struct cache_st *st = filter->ctx;
struct shared_context *shctx = shctx_ptr((struct cache *)filter->config->conf);
- struct cache_entry *object;
int ret;
+ ret = 0;
+
/*
* We need to skip the HTTP headers first, because we saved them in the
* http-response action.
@@ -210,31 +225,34 @@
else {
/* Forward data */
if (filter->ctx && st->first_block) {
- /* disable buffering if too much data (never greater than a buffer size */
- if (len - st->hdrs_len > global.tune.bufsize - global.tune.maxrewrite - st->first_block->len) {
- disable_cache:
- object = (struct cache_entry *)st->first_block->data;
- filter->ctx = NULL; /* disable cache */
- shctx_lock(shctx);
- shctx_row_dec_hot(shctx, st->first_block);
- object->eb.key = 0;
+ int to_append, append;
+ struct shared_block *fb;
+
+ to_append = MIN(ci_contig_data(msg->chn), len - st->hdrs_len);
+
+ /* Skip remaining headers to fill the cache */
+ c_adv(msg->chn, st->hdrs_len);
+
+ shctx_lock(shctx);
+ fb = shctx_row_reserve_hot(shctx, st->first_block, to_append);
+ if (!fb) {
shctx_unlock(shctx);
- pool_free(pool_head_cache_st, st);
- } else {
- /* Skip remaining headers to fill the cache */
- c_adv(msg->chn, st->hdrs_len);
- ret = shctx_row_data_append(shctx,
- st->first_block, NULL,
- (unsigned char *)ci_head(msg->chn),
- MIN(ci_contig_data(msg->chn), len - st->hdrs_len));
- /* Rewind the buffer to forward all data */
- c_rew(msg->chn, st->hdrs_len);
- st->hdrs_len = 0;
- if (ret)
- goto disable_cache;
+ disable_cache_entry(st, filter, shctx);
+ return len;
}
+ shctx_unlock(shctx);
+
+ append = shctx_row_data_append(shctx, st->first_block, st->first_block->last_append,
+ (unsigned char *)ci_head(msg->chn), to_append);
+ ret = st->hdrs_len + to_append - append;
+ /* Rewind the buffer to forward all data */
+ c_rew(msg->chn, st->hdrs_len);
+ st->hdrs_len = 0;
+ if (ret < 0)
+ disable_cache_entry(st, filter, shctx);
}
- ret = len;
+ else
+ ret = len;
}
if ((ret != len) ||
@@ -413,10 +431,6 @@
if (!(txn->req.flags & HTTP_MSGF_VER_11))
goto out;
- /* does not cache if Content-Length unknown */
- if (!(msg->flags & HTTP_MSGF_CNT_LEN))
- goto out;
-
/* cache only GET method */
if (txn->meth != HTTP_METH_GET)
goto out;
@@ -435,12 +449,8 @@
if (!(txn->flags & TX_CACHEABLE) || !(txn->flags & TX_CACHE_COOK))
goto out;
- if ((msg->sov + msg->body_len) > (global.tune.bufsize - global.tune.maxrewrite))
- goto out;
-
shctx_lock(shctx);
-
- first = shctx_row_reserve_hot(shctx, NULL, sizeof(struct cache_entry) + msg->sov + msg->body_len);
+ first = shctx_row_reserve_hot(shctx, NULL, sizeof(struct cache_entry) + msg->sov);
if (!first) {
shctx_unlock(shctx);
goto out;
@@ -456,7 +466,7 @@
/* reserve space for the cache_entry structure */
first->len = sizeof(struct cache_entry);
-
+ first->last_append = NULL;
/* cache the headers in a http action because it allows to chose what
* to cache, for example you might want to cache a response before
* modifying some HTTP headers, or on the contrary after modifying
@@ -529,14 +539,60 @@
shctx_unlock(shctx_ptr(cache));
}
-static void http_cache_io_handler(struct appctx *appctx)
+static int cache_channel_row_data_get(struct appctx *appctx, int len)
{
+ int ret, total;
struct stream_interface *si = appctx->owner;
struct channel *res = si_ic(si);
struct cache *cache = (struct cache *)appctx->rule->arg.act.p[0];
- struct cache_entry *cache_ptr = appctx->ctx.cache.entry;
struct shared_context *shctx = shctx_ptr(cache);
+ struct cache_entry *cache_ptr = appctx->ctx.cache.entry;
+ struct shared_block *blk, *next = appctx->ctx.cache.next;
+ int offset;
+
+ total = 0;
+ offset = 0;
+
+ if (!next) {
+ offset = sizeof(struct cache_entry);
+ next = block_ptr(cache_ptr);
+ }
+
+ blk = next;
+ list_for_each_entry_from(blk, &shctx->hot, list) {
+ int sz;
+
+ if (len <= 0)
+ break;
+
+ sz = MIN(len, shctx->block_size - offset);
+
+ ret = ci_putblk(res, (const char *)blk->data + offset, sz);
+ if (unlikely(offset))
+ offset = 0;
+ if (ret <= 0) {
+ if (ret == -3 || ret == -1) {
+ si_applet_cant_put(si);
+ break;
+ }
+ return -1;
+ }
+
+ total += sz;
+ len -= sz;
+ }
+ appctx->ctx.cache.next = blk;
+
+ return total;
+}
+
+static void http_cache_io_handler(struct appctx *appctx)
+{
+ struct stream_interface *si = appctx->owner;
+ struct channel *res = si_ic(si);
+ struct cache_entry *cache_ptr = appctx->ctx.cache.entry;
struct shared_block *first = block_ptr(cache_ptr);
+ int *sent = &appctx->ctx.cache.sent;
if (unlikely(si->state == SI_ST_DIS || si->state == SI_ST_CLO))
goto out;
@@ -552,18 +608,21 @@
/* buffer are aligned there, should be fine */
if (appctx->st0 == HTTP_CACHE_INIT) {
- int len = first->len - sizeof(struct cache_entry);
- if ((shctx_row_data_get(shctx, first, (unsigned char *)ci_tail(res), sizeof(struct cache_entry), len)) != 0) {
- /* should never get there, because at the moment, a
- * cache object can never be bigger than a buffer */
- abort();
+ int len = first->len - *sent - sizeof(struct cache_entry);
- si_applet_cant_put(si);
- goto out;
+ if (len > 0) {
+ int ret;
+
+ ret = cache_channel_row_data_get(appctx, len);
+ if (ret == -1)
+ appctx->st0 = HTTP_CACHE_END;
+ else
+ *sent += ret;
+ }
+ else {
+ *sent = 0;
+ appctx->st0 = HTTP_CACHE_FWD;
}
- b_add(&res->buf, len);
- res->total += len;
- appctx->st0 = HTTP_CACHE_FWD;
}
if (appctx->st0 == HTTP_CACHE_FWD) {
@@ -694,6 +753,8 @@
appctx->st0 = HTTP_CACHE_INIT;
appctx->rule = rule;
appctx->ctx.cache.entry = res;
+ appctx->ctx.cache.next = NULL;
+ appctx->ctx.cache.sent = 0;
return ACT_RET_CONT;
} else {
shctx_lock(shctx_ptr(cache));