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-rw-r--r--net/dccp/ccids/ccid3.c179
-rw-r--r--net/dccp/ccids/lib/loss_interval.c160
-rw-r--r--net/dccp/ccids/lib/loss_interval.h7
3 files changed, 176 insertions, 170 deletions
diff --git a/net/dccp/ccids/ccid3.c b/net/dccp/ccids/ccid3.c
index 52a71a900eb1..9d2e2c193cc6 100644
--- a/net/dccp/ccids/ccid3.c
+++ b/net/dccp/ccids/ccid3.c
@@ -819,167 +819,6 @@ static int ccid3_hc_rx_insert_options(struct sock *sk, struct sk_buff *skb)
819 return 0; 819 return 0;
820} 820}
821 821
822/* calculate first loss interval
823 *
824 * returns estimated loss interval in usecs */
825
826static u32 ccid3_hc_rx_calc_first_li(struct sock *sk,
827 struct list_head *hist_list,
828 struct timeval *last_feedback,
829 u16 s, u32 bytes_recv,
830 u32 previous_x_recv)
831{
832 struct dccp_rx_hist_entry *entry, *next, *tail = NULL;
833 u32 x_recv, p;
834 suseconds_t rtt, delta;
835 struct timeval tstamp = { 0, 0 };
836 int interval = 0;
837 int win_count = 0;
838 int step = 0;
839 u64 fval;
840
841 list_for_each_entry_safe(entry, next, hist_list, dccphrx_node) {
842 if (dccp_rx_hist_entry_data_packet(entry)) {
843 tail = entry;
844
845 switch (step) {
846 case 0:
847 tstamp = entry->dccphrx_tstamp;
848 win_count = entry->dccphrx_ccval;
849 step = 1;
850 break;
851 case 1:
852 interval = win_count - entry->dccphrx_ccval;
853 if (interval < 0)
854 interval += TFRC_WIN_COUNT_LIMIT;
855 if (interval > 4)
856 goto found;
857 break;
858 }
859 }
860 }
861
862 if (unlikely(step == 0)) {
863 DCCP_WARN("%s(%p), packet history has no data packets!\n",
864 dccp_role(sk), sk);
865 return ~0;
866 }
867
868 if (unlikely(interval == 0)) {
869 DCCP_WARN("%s(%p), Could not find a win_count interval > 0."
870 "Defaulting to 1\n", dccp_role(sk), sk);
871 interval = 1;
872 }
873found:
874 if (!tail) {
875 DCCP_CRIT("tail is null\n");
876 return ~0;
877 }
878
879 delta = timeval_delta(&tstamp, &tail->dccphrx_tstamp);
880 DCCP_BUG_ON(delta < 0);
881
882 rtt = delta * 4 / interval;
883 ccid3_pr_debug("%s(%p), approximated RTT to %dus\n",
884 dccp_role(sk), sk, (int)rtt);
885
886 /*
887 * Determine the length of the first loss interval via inverse lookup.
888 * Assume that X_recv can be computed by the throughput equation
889 * s
890 * X_recv = --------
891 * R * fval
892 * Find some p such that f(p) = fval; return 1/p [RFC 3448, 6.3.1].
893 */
894 if (rtt == 0) { /* would result in divide-by-zero */
895 DCCP_WARN("RTT==0\n");
896 return ~0;
897 }
898
899 dccp_timestamp(sk, &tstamp);
900 delta = timeval_delta(&tstamp, last_feedback);
901 DCCP_BUG_ON(delta <= 0);
902
903 x_recv = scaled_div32(bytes_recv, delta);
904 if (x_recv == 0) { /* would also trigger divide-by-zero */
905 DCCP_WARN("X_recv==0\n");
906 if (previous_x_recv == 0) {
907 DCCP_BUG("stored value of X_recv is zero");
908 return ~0;
909 }
910 x_recv = previous_x_recv;
911 }
912
913 fval = scaled_div(s, rtt);
914 fval = scaled_div32(fval, x_recv);
915 p = tfrc_calc_x_reverse_lookup(fval);
916
917 ccid3_pr_debug("%s(%p), receive rate=%u bytes/s, implied "
918 "loss rate=%u\n", dccp_role(sk), sk, x_recv, p);
919
920 if (p == 0)
921 return ~0;
922 else
923 return 1000000 / p;
924}
925
926static void ccid3_hc_rx_update_li(struct sock *sk,
927 struct dccp_li_hist *li_hist,
928 struct list_head *li_hist_list,
929 struct list_head *hist_list,
930 struct timeval *last_feedback,
931 u16 s, u32 bytes_recv,
932 u32 previous_x_recv,
933 u64 seq_loss, u8 win_loss)
934{
935 struct dccp_li_hist_entry *head;
936 u64 seq_temp;
937
938 if (list_empty(li_hist_list)) {
939 if (!dccp_li_hist_interval_new(li_hist, li_hist_list,
940 seq_loss, win_loss))
941 return;
942
943 head = list_entry(li_hist_list->next, struct dccp_li_hist_entry,
944 dccplih_node);
945 head->dccplih_interval =
946 ccid3_hc_rx_calc_first_li(sk, hist_list,
947 last_feedback, s,
948 bytes_recv,
949 previous_x_recv);
950 } else {
951 struct dccp_li_hist_entry *entry;
952 struct list_head *tail;
953
954 head = list_entry(li_hist_list->next, struct dccp_li_hist_entry,
955 dccplih_node);
956 /* FIXME win count check removed as was wrong */
957 /* should make this check with receive history */
958 /* and compare there as per section 10.2 of RFC4342 */
959
960 /* new loss event detected */
961 /* calculate last interval length */
962 seq_temp = dccp_delta_seqno(head->dccplih_seqno, seq_loss);
963 entry = dccp_li_hist_entry_new(li_hist, GFP_ATOMIC);
964
965 if (entry == NULL) {
966 DCCP_BUG("out of memory - can not allocate entry");
967 return;
968 }
969
970 list_add(&entry->dccplih_node, li_hist_list);
971
972 tail = li_hist_list->prev;
973 list_del(tail);
974 kmem_cache_free(li_hist->dccplih_slab, tail);
975
976 /* Create the newest interval */
977 entry->dccplih_seqno = seq_loss;
978 entry->dccplih_interval = seq_temp;
979 entry->dccplih_win_count = win_loss;
980 }
981}
982
983static int ccid3_hc_rx_detect_loss(struct sock *sk, 822static int ccid3_hc_rx_detect_loss(struct sock *sk,
984 struct dccp_rx_hist_entry *packet) 823 struct dccp_rx_hist_entry *packet)
985{ 824{
@@ -1005,15 +844,15 @@ static int ccid3_hc_rx_detect_loss(struct sock *sk,
1005 while (dccp_delta_seqno(hcrx->ccid3hcrx_seqno_nonloss, seqno) 844 while (dccp_delta_seqno(hcrx->ccid3hcrx_seqno_nonloss, seqno)
1006 > TFRC_RECV_NUM_LATE_LOSS) { 845 > TFRC_RECV_NUM_LATE_LOSS) {
1007 loss = 1; 846 loss = 1;
1008 ccid3_hc_rx_update_li(sk, ccid3_li_hist, 847 dccp_li_update_li(sk, ccid3_li_hist,
1009 &hcrx->ccid3hcrx_li_hist, 848 &hcrx->ccid3hcrx_li_hist,
1010 &hcrx->ccid3hcrx_hist, 849 &hcrx->ccid3hcrx_hist,
1011 &hcrx->ccid3hcrx_tstamp_last_feedback, 850 &hcrx->ccid3hcrx_tstamp_last_feedback,
1012 hcrx->ccid3hcrx_s, 851 hcrx->ccid3hcrx_s,
1013 hcrx->ccid3hcrx_bytes_recv, 852 hcrx->ccid3hcrx_bytes_recv,
1014 hcrx->ccid3hcrx_x_recv, 853 hcrx->ccid3hcrx_x_recv,
1015 hcrx->ccid3hcrx_seqno_nonloss, 854 hcrx->ccid3hcrx_seqno_nonloss,
1016 hcrx->ccid3hcrx_ccval_nonloss); 855 hcrx->ccid3hcrx_ccval_nonloss);
1017 tmp_seqno = hcrx->ccid3hcrx_seqno_nonloss; 856 tmp_seqno = hcrx->ccid3hcrx_seqno_nonloss;
1018 dccp_inc_seqno(&tmp_seqno); 857 dccp_inc_seqno(&tmp_seqno);
1019 hcrx->ccid3hcrx_seqno_nonloss = tmp_seqno; 858 hcrx->ccid3hcrx_seqno_nonloss = tmp_seqno;
diff --git a/net/dccp/ccids/lib/loss_interval.c b/net/dccp/ccids/lib/loss_interval.c
index 3829afc31176..ee59fde6653f 100644
--- a/net/dccp/ccids/lib/loss_interval.c
+++ b/net/dccp/ccids/lib/loss_interval.c
@@ -15,6 +15,8 @@
15#include <net/sock.h> 15#include <net/sock.h>
16#include "../../dccp.h" 16#include "../../dccp.h"
17#include "loss_interval.h" 17#include "loss_interval.h"
18#include "packet_history.h"
19#include "tfrc.h"
18 20
19struct dccp_li_hist *dccp_li_hist_new(const char *name) 21struct dccp_li_hist *dccp_li_hist_new(const char *name)
20{ 22{
@@ -141,3 +143,161 @@ int dccp_li_hist_interval_new(struct dccp_li_hist *hist,
141} 143}
142 144
143EXPORT_SYMBOL_GPL(dccp_li_hist_interval_new); 145EXPORT_SYMBOL_GPL(dccp_li_hist_interval_new);
146
147/* calculate first loss interval
148 *
149 * returns estimated loss interval in usecs */
150static u32 dccp_li_calc_first_li(struct sock *sk,
151 struct list_head *hist_list,
152 struct timeval *last_feedback,
153 u16 s, u32 bytes_recv,
154 u32 previous_x_recv)
155{
156 struct dccp_rx_hist_entry *entry, *next, *tail = NULL;
157 u32 x_recv, p;
158 suseconds_t rtt, delta;
159 struct timeval tstamp = { 0, 0 };
160 int interval = 0;
161 int win_count = 0;
162 int step = 0;
163 u64 fval;
164
165 list_for_each_entry_safe(entry, next, hist_list, dccphrx_node) {
166 if (dccp_rx_hist_entry_data_packet(entry)) {
167 tail = entry;
168
169 switch (step) {
170 case 0:
171 tstamp = entry->dccphrx_tstamp;
172 win_count = entry->dccphrx_ccval;
173 step = 1;
174 break;
175 case 1:
176 interval = win_count - entry->dccphrx_ccval;
177 if (interval < 0)
178 interval += TFRC_WIN_COUNT_LIMIT;
179 if (interval > 4)
180 goto found;
181 break;
182 }
183 }
184 }
185
186 if (unlikely(step == 0)) {
187 DCCP_WARN("%s(%p), packet history has no data packets!\n",
188 dccp_role(sk), sk);
189 return ~0;
190 }
191
192 if (unlikely(interval == 0)) {
193 DCCP_WARN("%s(%p), Could not find a win_count interval > 0."
194 "Defaulting to 1\n", dccp_role(sk), sk);
195 interval = 1;
196 }
197found:
198 if (!tail) {
199 DCCP_CRIT("tail is null\n");
200 return ~0;
201 }
202
203 delta = timeval_delta(&tstamp, &tail->dccphrx_tstamp);
204 DCCP_BUG_ON(delta < 0);
205
206 rtt = delta * 4 / interval;
207 dccp_pr_debug("%s(%p), approximated RTT to %dus\n",
208 dccp_role(sk), sk, (int)rtt);
209
210 /*
211 * Determine the length of the first loss interval via inverse lookup.
212 * Assume that X_recv can be computed by the throughput equation
213 * s
214 * X_recv = --------
215 * R * fval
216 * Find some p such that f(p) = fval; return 1/p [RFC 3448, 6.3.1].
217 */
218 if (rtt == 0) { /* would result in divide-by-zero */
219 DCCP_WARN("RTT==0\n");
220 return ~0;
221 }
222
223 dccp_timestamp(sk, &tstamp);
224 delta = timeval_delta(&tstamp, last_feedback);
225 DCCP_BUG_ON(delta <= 0);
226
227 x_recv = scaled_div32(bytes_recv, delta);
228 if (x_recv == 0) { /* would also trigger divide-by-zero */
229 DCCP_WARN("X_recv==0\n");
230 if (previous_x_recv == 0) {
231 DCCP_BUG("stored value of X_recv is zero");
232 return ~0;
233 }
234 x_recv = previous_x_recv;
235 }
236
237 fval = scaled_div(s, rtt);
238 fval = scaled_div32(fval, x_recv);
239 p = tfrc_calc_x_reverse_lookup(fval);
240
241 dccp_pr_debug("%s(%p), receive rate=%u bytes/s, implied "
242 "loss rate=%u\n", dccp_role(sk), sk, x_recv, p);
243
244 if (p == 0)
245 return ~0;
246 else
247 return 1000000 / p;
248}
249
250void dccp_li_update_li(struct sock *sk, struct dccp_li_hist *li_hist,
251 struct list_head *li_hist_list,
252 struct list_head *hist_list,
253 struct timeval *last_feedback, u16 s, u32 bytes_recv,
254 u32 previous_x_recv, u64 seq_loss, u8 win_loss)
255{
256 struct dccp_li_hist_entry *head;
257 u64 seq_temp;
258
259 if (list_empty(li_hist_list)) {
260 if (!dccp_li_hist_interval_new(li_hist, li_hist_list,
261 seq_loss, win_loss))
262 return;
263
264 head = list_entry(li_hist_list->next, struct dccp_li_hist_entry,
265 dccplih_node);
266 head->dccplih_interval = dccp_li_calc_first_li(sk, hist_list,
267 last_feedback,
268 s, bytes_recv,
269 previous_x_recv);
270 } else {
271 struct dccp_li_hist_entry *entry;
272 struct list_head *tail;
273
274 head = list_entry(li_hist_list->next, struct dccp_li_hist_entry,
275 dccplih_node);
276 /* FIXME win count check removed as was wrong */
277 /* should make this check with receive history */
278 /* and compare there as per section 10.2 of RFC4342 */
279
280 /* new loss event detected */
281 /* calculate last interval length */
282 seq_temp = dccp_delta_seqno(head->dccplih_seqno, seq_loss);
283 entry = dccp_li_hist_entry_new(li_hist, GFP_ATOMIC);
284
285 if (entry == NULL) {
286 DCCP_BUG("out of memory - can not allocate entry");
287 return;
288 }
289
290 list_add(&entry->dccplih_node, li_hist_list);
291
292 tail = li_hist_list->prev;
293 list_del(tail);
294 kmem_cache_free(li_hist->dccplih_slab, tail);
295
296 /* Create the newest interval */
297 entry->dccplih_seqno = seq_loss;
298 entry->dccplih_interval = seq_temp;
299 entry->dccplih_win_count = win_loss;
300 }
301}
302
303EXPORT_SYMBOL_GPL(dccp_li_update_li);
diff --git a/net/dccp/ccids/lib/loss_interval.h b/net/dccp/ccids/lib/loss_interval.h
index 1e48fe323006..17f173a30055 100644
--- a/net/dccp/ccids/lib/loss_interval.h
+++ b/net/dccp/ccids/lib/loss_interval.h
@@ -54,4 +54,11 @@ extern u32 dccp_li_hist_calc_i_mean(struct list_head *list);
54 54
55extern int dccp_li_hist_interval_new(struct dccp_li_hist *hist, 55extern int dccp_li_hist_interval_new(struct dccp_li_hist *hist,
56 struct list_head *list, const u64 seq_loss, const u8 win_loss); 56 struct list_head *list, const u64 seq_loss, const u8 win_loss);
57
58extern void dccp_li_update_li(struct sock *sk, struct dccp_li_hist *li_hist,
59 struct list_head *li_hist_list,
60 struct list_head *hist_list,
61 struct timeval *last_feedback, u16 s,
62 u32 bytes_recv, u32 previous_x_recv,
63 u64 seq_loss, u8 win_loss);
57#endif /* _DCCP_LI_HIST_ */ 64#endif /* _DCCP_LI_HIST_ */
generated by cgit v1.2.2 (git 2.25.0) at 2024-11-25 11:37:08 -0500