OPTIM: http: optimize the response forward state machine
By replacing the if/else series with a switch/case, we could save
another 20% on the worst case (chunks of 1 byte).
diff --git a/src/proto_http.c b/src/proto_http.c
index 7abfe31..087cd47 100644
--- a/src/proto_http.c
+++ b/src/proto_http.c
@@ -5784,6 +5784,7 @@
static struct buffer *tmpbuf = NULL;
int compressing = 0;
int consumed_data = 0;
+ int ret;
if (unlikely(msg->msg_state < HTTP_MSG_BODY))
return 0;
@@ -5824,7 +5825,7 @@
}
if (s->comp_algo != NULL) {
- int ret = http_compression_buffer_init(s, res->buf, tmpbuf); /* init a buffer with headers */
+ ret = http_compression_buffer_init(s, res->buf, tmpbuf); /* init a buffer with headers */
if (ret < 0)
goto missing_data; /* not enough spaces in buffers */
compressing = 1;
@@ -5843,10 +5844,8 @@
}
}
- if (msg->msg_state == HTTP_MSG_DATA) {
- int ret;
-
- /* must still forward */
+ switch (msg->msg_state - HTTP_MSG_DATA) {
+ case HTTP_MSG_DATA - HTTP_MSG_DATA: /* must still forward */
if (compressing) {
consumed_data += ret = http_compression_buffer_add_data(s, res->buf, tmpbuf);
if (ret < 0)
@@ -5865,15 +5864,37 @@
http_compression_buffer_end(s, &res->buf, &tmpbuf, 1);
compressing = 0;
}
+ break;
}
- }
- else if (msg->msg_state == HTTP_MSG_CHUNK_SIZE) {
+ /* fall through for HTTP_MSG_CHUNK_CRLF */
+
+ case HTTP_MSG_CHUNK_CRLF - HTTP_MSG_DATA:
+ /* we want the CRLF after the data */
+
+ ret = http_skip_chunk_crlf(msg);
+ if (ret == 0)
+ goto missing_data;
+ else if (ret < 0) {
+ if (msg->err_pos >= 0)
+ http_capture_bad_message(&s->be->invalid_rep, s, msg, HTTP_MSG_CHUNK_CRLF, s->fe);
+ goto return_bad_res;
+ }
+ /* skipping data in buffer for compression */
+ if (compressing) {
+ b_adv(res->buf, msg->next);
+ msg->next = 0;
+ msg->sov = 0;
+ msg->sol = 0;
+ }
+ /* we're in MSG_CHUNK_SIZE now, fall through */
+
+ case HTTP_MSG_CHUNK_SIZE - HTTP_MSG_DATA:
/* read the chunk size and assign it to ->chunk_len, then
* set ->sov and ->next to point to the body and switch to DATA or
* TRAILERS state.
*/
- int ret = http_parse_chunk_size(msg);
+ ret = http_parse_chunk_size(msg);
if (ret == 0)
goto missing_data;
else if (ret < 0) {
@@ -5896,30 +5917,10 @@
}
}
/* otherwise we're in HTTP_MSG_DATA or HTTP_MSG_TRAILERS state */
- }
- else if (msg->msg_state == HTTP_MSG_CHUNK_CRLF) {
- /* we want the CRLF after the data */
- int ret = http_skip_chunk_crlf(msg);
-
- if (ret == 0)
- goto missing_data;
- else if (ret < 0) {
- if (msg->err_pos >= 0)
- http_capture_bad_message(&s->be->invalid_rep, s, msg, HTTP_MSG_CHUNK_CRLF, s->fe);
- goto return_bad_res;
- }
- /* skipping data in buffer for compression */
- if (compressing) {
- b_adv(res->buf, msg->next);
- msg->next = 0;
- msg->sov = 0;
- msg->sol = 0;
- }
- /* we're in MSG_CHUNK_SIZE now */
- }
- else if (msg->msg_state == HTTP_MSG_TRAILERS) {
- int ret = http_forward_trailers(msg);
+ break;
+ case HTTP_MSG_TRAILERS - HTTP_MSG_DATA:
+ ret = http_forward_trailers(msg);
if (ret == 0)
goto missing_data;
else if (ret < 0) {
@@ -5932,11 +5933,12 @@
channel_forward(res, msg->next);
msg->next = 0;
}
- /* we're in HTTP_MSG_DONE now */
- }
- else {
- int old_state = msg->msg_state;
+ /* we're in HTTP_MSG_DONE now, fall through */
+
+ default:
/* other states, DONE...TUNNEL */
+
+ ret = msg->msg_state;
/* for keep-alive we don't want to forward closes on DONE */
if ((txn->flags & TX_CON_WANT_MSK) == TX_CON_WANT_KAL ||
(txn->flags & TX_CON_WANT_MSK) == TX_CON_WANT_SCL)
@@ -5954,7 +5956,7 @@
goto aborted_xfer;
}
if (msg->err_pos >= 0)
- http_capture_bad_message(&s->be->invalid_rep, s, msg, old_state, s->fe);
+ http_capture_bad_message(&s->be->invalid_rep, s, msg, ret, s->fe);
goto return_bad_res;
}
return 1;