diff options
Diffstat (limited to 'net/dccp/ccids/ccid3.h')
-rw-r--r-- | net/dccp/ccids/ccid3.h | 19 |
1 files changed, 14 insertions, 5 deletions
diff --git a/net/dccp/ccids/ccid3.h b/net/dccp/ccids/ccid3.h index 0cfcfff8f5f..92a5e1688a0 100644 --- a/net/dccp/ccids/ccid3.h +++ b/net/dccp/ccids/ccid3.h @@ -47,12 +47,23 @@ /* Two seconds as per RFC 3448 4.2 */ #define TFRC_INITIAL_TIMEOUT (2 * USEC_PER_SEC) -/* In usecs - half the scheduling granularity as per RFC3448 4.6 */ -#define TFRC_OPSYS_HALF_TIME_GRAN (USEC_PER_SEC / (2 * HZ)) - /* Parameter t_mbi from [RFC 3448, 4.3]: backoff interval in seconds */ #define TFRC_T_MBI 64 +/* + * The t_delta parameter (RFC 3448, 4.6): delays of less than %USEC_PER_MSEC are + * rounded down to 0, since sk_reset_timer() here uses millisecond granularity. + * Hence we can use a constant t_delta = %USEC_PER_MSEC when HZ >= 500. A coarse + * resolution of HZ < 500 means that the error is below one timer tick (t_gran) + * when using the constant t_delta = t_gran / 2 = %USEC_PER_SEC / (2 * HZ). + */ +#if (HZ >= 500) +# define TFRC_T_DELTA USEC_PER_MSEC +#else +# define TFRC_T_DELTA (USEC_PER_SEC / (2 * HZ)) +#warning Coarse CONFIG_HZ resolution -- higher value recommended for TFRC. +#endif + enum ccid3_options { TFRC_OPT_LOSS_EVENT_RATE = 192, TFRC_OPT_LOSS_INTERVALS = 193, @@ -92,7 +103,6 @@ enum ccid3_hc_tx_states { * @no_feedback_timer - Handle to no feedback timer * @t_ld - Time last doubled during slow start * @t_nom - Nominal send time of next packet - * @delta - Send timer delta (RFC 3448, 4.6) in usecs * @hist - Packet history * @options_received - Parsed set of retrieved options */ @@ -111,7 +121,6 @@ struct ccid3_hc_tx_sock { struct timer_list no_feedback_timer; ktime_t t_ld; ktime_t t_nom; - u32 delta; struct tfrc_tx_hist_entry *hist; struct ccid3_options_received options_received; }; |