diff options
author | Gerrit Renker <gerrit@erg.abdn.ac.uk> | 2007-03-20 14:19:07 -0400 |
---|---|---|
committer | David S. Miller <davem@sunset.davemloft.net> | 2007-04-26 01:26:59 -0400 |
commit | 0c150efb280986db7958cf2a559b91d826241e59 (patch) | |
tree | f74291b4ea523ad2461192f680b892d2e19f2652 /net/dccp | |
parent | a21f9f96cd035b0d9aec32d80ea0152672fbed42 (diff) |
[CCID3]: Handle Idle and Application-Limited periods
This updates the code with regard to handling idle and application-limited
periods as specified in [RFC 4342, 5.1].
Background:
Diffstat (limited to 'net/dccp')
-rw-r--r-- | net/dccp/ccids/ccid3.c | 84 |
1 files changed, 40 insertions, 44 deletions
diff --git a/net/dccp/ccids/ccid3.c b/net/dccp/ccids/ccid3.c index 8d33a09608e9..35123c19a08f 100644 --- a/net/dccp/ccids/ccid3.c +++ b/net/dccp/ccids/ccid3.c | |||
@@ -133,12 +133,23 @@ static void ccid3_hc_tx_update_x(struct sock *sk, struct timeval *now) | |||
133 | 133 | ||
134 | { | 134 | { |
135 | struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); | 135 | struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); |
136 | __u64 min_rate = 2 * hctx->ccid3hctx_x_recv; | ||
136 | const __u64 old_x = hctx->ccid3hctx_x; | 137 | const __u64 old_x = hctx->ccid3hctx_x; |
137 | 138 | ||
139 | /* | ||
140 | * Handle IDLE periods: do not reduce below RFC3390 initial sending rate | ||
141 | * when idling [RFC 4342, 5.1]. See also draft-ietf-dccp-rfc3448bis. | ||
142 | * For consistency with X and X_recv, min_rate is also scaled by 2^6. | ||
143 | */ | ||
144 | if (unlikely(hctx->ccid3hctx_idle)) { | ||
145 | min_rate = rfc3390_initial_rate(sk); | ||
146 | min_rate = max(min_rate, 2 * hctx->ccid3hctx_x_recv); | ||
147 | } | ||
148 | |||
138 | if (hctx->ccid3hctx_p > 0) { | 149 | if (hctx->ccid3hctx_p > 0) { |
139 | 150 | ||
140 | hctx->ccid3hctx_x = min(((__u64)hctx->ccid3hctx_x_calc) << 6, | 151 | hctx->ccid3hctx_x = min(((__u64)hctx->ccid3hctx_x_calc) << 6, |
141 | hctx->ccid3hctx_x_recv * 2); | 152 | min_rate); |
142 | hctx->ccid3hctx_x = max(hctx->ccid3hctx_x, | 153 | hctx->ccid3hctx_x = max(hctx->ccid3hctx_x, |
143 | (((__u64)hctx->ccid3hctx_s) << 6) / | 154 | (((__u64)hctx->ccid3hctx_s) << 6) / |
144 | TFRC_T_MBI); | 155 | TFRC_T_MBI); |
@@ -147,7 +158,7 @@ static void ccid3_hc_tx_update_x(struct sock *sk, struct timeval *now) | |||
147 | (suseconds_t)hctx->ccid3hctx_rtt >= 0) { | 158 | (suseconds_t)hctx->ccid3hctx_rtt >= 0) { |
148 | 159 | ||
149 | hctx->ccid3hctx_x = | 160 | hctx->ccid3hctx_x = |
150 | max(2 * min(hctx->ccid3hctx_x, hctx->ccid3hctx_x_recv), | 161 | max(min(2 * hctx->ccid3hctx_x, min_rate), |
151 | scaled_div(((__u64)hctx->ccid3hctx_s) << 6, | 162 | scaled_div(((__u64)hctx->ccid3hctx_s) << 6, |
152 | hctx->ccid3hctx_rtt)); | 163 | hctx->ccid3hctx_rtt)); |
153 | hctx->ccid3hctx_t_ld = *now; | 164 | hctx->ccid3hctx_t_ld = *now; |
@@ -209,6 +220,7 @@ static void ccid3_hc_tx_no_feedback_timer(unsigned long data) | |||
209 | { | 220 | { |
210 | struct sock *sk = (struct sock *)data; | 221 | struct sock *sk = (struct sock *)data; |
211 | struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); | 222 | struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk); |
223 | struct timeval now; | ||
212 | unsigned long t_nfb = USEC_PER_SEC / 5; | 224 | unsigned long t_nfb = USEC_PER_SEC / 5; |
213 | 225 | ||
214 | bh_lock_sock(sk); | 226 | bh_lock_sock(sk); |
@@ -221,6 +233,8 @@ static void ccid3_hc_tx_no_feedback_timer(unsigned long data) | |||
221 | ccid3_pr_debug("%s(%p, state=%s) - entry \n", dccp_role(sk), sk, | 233 | ccid3_pr_debug("%s(%p, state=%s) - entry \n", dccp_role(sk), sk, |
222 | ccid3_tx_state_name(hctx->ccid3hctx_state)); | 234 | ccid3_tx_state_name(hctx->ccid3hctx_state)); |
223 | 235 | ||
236 | hctx->ccid3hctx_idle = 1; | ||
237 | |||
224 | switch (hctx->ccid3hctx_state) { | 238 | switch (hctx->ccid3hctx_state) { |
225 | case TFRC_SSTATE_NO_FBACK: | 239 | case TFRC_SSTATE_NO_FBACK: |
226 | /* RFC 3448, 4.4: Halve send rate directly */ | 240 | /* RFC 3448, 4.4: Halve send rate directly */ |
@@ -239,49 +253,33 @@ static void ccid3_hc_tx_no_feedback_timer(unsigned long data) | |||
239 | break; | 253 | break; |
240 | case TFRC_SSTATE_FBACK: | 254 | case TFRC_SSTATE_FBACK: |
241 | /* | 255 | /* |
242 | * Check if IDLE since last timeout and recv rate is less than | 256 | * Modify the cached value of X_recv [RFC 3448, 4.4] |
243 | * 4 packets (in units of 64*bytes/sec) per RTT | 257 | * |
258 | * If (p == 0 || X_calc > 2 * X_recv) | ||
259 | * X_recv = max(X_recv / 2, s / (2 * t_mbi)); | ||
260 | * Else | ||
261 | * X_recv = X_calc / 4; | ||
262 | * | ||
263 | * Note that X_recv is scaled by 2^6 while X_calc is not | ||
244 | */ | 264 | */ |
245 | if (!hctx->ccid3hctx_idle || | 265 | BUG_ON(hctx->ccid3hctx_p && !hctx->ccid3hctx_x_calc); |
246 | (hctx->ccid3hctx_x_recv >= 4 * | ||
247 | scaled_div(((__u64)hctx->ccid3hctx_s) << 6, | ||
248 | hctx->ccid3hctx_rtt))) { | ||
249 | struct timeval now; | ||
250 | 266 | ||
251 | ccid3_pr_debug("%s(%p, state=%s), not idle\n", | 267 | if (hctx->ccid3hctx_p == 0 || |
252 | dccp_role(sk), sk, | 268 | (hctx->ccid3hctx_x_calc > (hctx->ccid3hctx_x_recv >> 5))) { |
253 | ccid3_tx_state_name(hctx->ccid3hctx_state)); | ||
254 | 269 | ||
255 | /* | 270 | hctx->ccid3hctx_x_recv = |
256 | * Modify the cached value of X_recv [RFC 3448, 4.4] | 271 | max(hctx->ccid3hctx_x_recv / 2, |
257 | * | 272 | (((__u64)hctx->ccid3hctx_s) << 6) / |
258 | * If (p == 0 || X_calc > 2 * X_recv) | 273 | (2 * TFRC_T_MBI)); |
259 | * X_recv = max(X_recv / 2, s / (2 * t_mbi)); | 274 | |
260 | * Else | 275 | if (hctx->ccid3hctx_p == 0) |
261 | * X_recv = X_calc / 4; | 276 | dccp_timestamp(sk, &now); |
262 | * | 277 | } else { |
263 | * Note that X_recv is scaled by 2^6 while X_calc is not | 278 | hctx->ccid3hctx_x_recv = hctx->ccid3hctx_x_calc; |
264 | */ | 279 | hctx->ccid3hctx_x_recv <<= 4; |
265 | BUG_ON(hctx->ccid3hctx_p && !hctx->ccid3hctx_x_calc); | ||
266 | |||
267 | if (hctx->ccid3hctx_p == 0 || | ||
268 | (hctx->ccid3hctx_x_calc > | ||
269 | (hctx->ccid3hctx_x_recv >> 5))) { | ||
270 | |||
271 | hctx->ccid3hctx_x_recv = | ||
272 | max(hctx->ccid3hctx_x_recv / 2, | ||
273 | (((__u64)hctx->ccid3hctx_s) << 6) / | ||
274 | (2 * TFRC_T_MBI)); | ||
275 | |||
276 | if (hctx->ccid3hctx_p == 0) | ||
277 | dccp_timestamp(sk, &now); | ||
278 | } else { | ||
279 | hctx->ccid3hctx_x_recv = hctx->ccid3hctx_x_calc; | ||
280 | hctx->ccid3hctx_x_recv <<= 4; | ||
281 | } | ||
282 | /* Now recalculate X [RFC 3448, 4.3, step (4)] */ | ||
283 | ccid3_hc_tx_update_x(sk, &now); | ||
284 | } | 280 | } |
281 | /* Now recalculate X [RFC 3448, 4.3, step (4)] */ | ||
282 | ccid3_hc_tx_update_x(sk, &now); | ||
285 | /* | 283 | /* |
286 | * Schedule no feedback timer to expire in | 284 | * Schedule no feedback timer to expire in |
287 | * max(t_RTO, 2 * s/X) = max(t_RTO, 2 * t_ipi) | 285 | * max(t_RTO, 2 * s/X) = max(t_RTO, 2 * t_ipi) |
@@ -296,8 +294,6 @@ static void ccid3_hc_tx_no_feedback_timer(unsigned long data) | |||
296 | goto out; | 294 | goto out; |
297 | } | 295 | } |
298 | 296 | ||
299 | hctx->ccid3hctx_idle = 1; | ||
300 | |||
301 | restart_timer: | 297 | restart_timer: |
302 | sk_reset_timer(sk, &hctx->ccid3hctx_no_feedback_timer, | 298 | sk_reset_timer(sk, &hctx->ccid3hctx_no_feedback_timer, |
303 | jiffies + usecs_to_jiffies(t_nfb)); | 299 | jiffies + usecs_to_jiffies(t_nfb)); |
@@ -377,6 +373,7 @@ static int ccid3_hc_tx_send_packet(struct sock *sk, struct sk_buff *skb) | |||
377 | /* prepare to send now (add options etc.) */ | 373 | /* prepare to send now (add options etc.) */ |
378 | dp->dccps_hc_tx_insert_options = 1; | 374 | dp->dccps_hc_tx_insert_options = 1; |
379 | DCCP_SKB_CB(skb)->dccpd_ccval = hctx->ccid3hctx_last_win_count; | 375 | DCCP_SKB_CB(skb)->dccpd_ccval = hctx->ccid3hctx_last_win_count; |
376 | hctx->ccid3hctx_idle = 0; | ||
380 | 377 | ||
381 | /* set the nominal send time for the next following packet */ | 378 | /* set the nominal send time for the next following packet */ |
382 | timeval_add_usecs(&hctx->ccid3hctx_t_nom, hctx->ccid3hctx_t_ipi); | 379 | timeval_add_usecs(&hctx->ccid3hctx_t_nom, hctx->ccid3hctx_t_ipi); |
@@ -407,7 +404,6 @@ static void ccid3_hc_tx_packet_sent(struct sock *sk, int more, | |||
407 | packet->dccphtx_seqno = dccp_sk(sk)->dccps_gss; | 404 | packet->dccphtx_seqno = dccp_sk(sk)->dccps_gss; |
408 | packet->dccphtx_rtt = hctx->ccid3hctx_rtt; | 405 | packet->dccphtx_rtt = hctx->ccid3hctx_rtt; |
409 | packet->dccphtx_sent = 1; | 406 | packet->dccphtx_sent = 1; |
410 | hctx->ccid3hctx_idle = 0; | ||
411 | } | 407 | } |
412 | 408 | ||
413 | static void ccid3_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb) | 409 | static void ccid3_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb) |