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Diffstat (limited to 'net/ipv4/tcp_cubic.c')
-rw-r--r--net/ipv4/tcp_cubic.c68
1 files changed, 34 insertions, 34 deletions
diff --git a/net/ipv4/tcp_cubic.c b/net/ipv4/tcp_cubic.c
index 6ad184802266..9a582fb4ef9f 100644
--- a/net/ipv4/tcp_cubic.c
+++ b/net/ipv4/tcp_cubic.c
@@ -26,16 +26,16 @@
*/
#define BICTCP_HZ 10 /* BIC HZ 2^10 = 1024 */
-static int fast_convergence = 1;
-static int max_increment = 16;
-static int beta = 819; /* = 819/1024 (BICTCP_BETA_SCALE) */
-static int initial_ssthresh = 100;
-static int bic_scale = 41;
-static int tcp_friendliness = 1;
+static int fast_convergence __read_mostly = 1;
+static int max_increment __read_mostly = 16;
+static int beta __read_mostly = 819; /* = 819/1024 (BICTCP_BETA_SCALE) */
+static int initial_ssthresh __read_mostly = 100;
+static int bic_scale __read_mostly = 41;
+static int tcp_friendliness __read_mostly = 1;
-static u32 cube_rtt_scale;
-static u32 beta_scale;
-static u64 cube_factor;
+static u32 cube_rtt_scale __read_mostly;
+static u32 beta_scale __read_mostly;
+static u64 cube_factor __read_mostly;
/* Note parameters that are used for precomputing scale factors are read-only */
module_param(fast_convergence, int, 0644);
@@ -175,42 +175,42 @@ static inline void bictcp_update(struct bictcp *ca, u32 cwnd)
}
}
- /* cubic function - calc*/
- /* calculate c * time^3 / rtt,
- * while considering overflow in calculation of time^3
+ /* cubic function - calc*/
+ /* calculate c * time^3 / rtt,
+ * while considering overflow in calculation of time^3
* (so time^3 is done by using 64 bit)
* and without the support of division of 64bit numbers
* (so all divisions are done by using 32 bit)
- * also NOTE the unit of those veriables
- * time = (t - K) / 2^bictcp_HZ
- * c = bic_scale >> 10
+ * also NOTE the unit of those veriables
+ * time = (t - K) / 2^bictcp_HZ
+ * c = bic_scale >> 10
* rtt = (srtt >> 3) / HZ
* !!! The following code does not have overflow problems,
* if the cwnd < 1 million packets !!!
- */
+ */
/* change the unit from HZ to bictcp_HZ */
- t = ((tcp_time_stamp + (ca->delay_min>>3) - ca->epoch_start)
+ t = ((tcp_time_stamp + (ca->delay_min>>3) - ca->epoch_start)
<< BICTCP_HZ) / HZ;
- if (t < ca->bic_K) /* t - K */
+ if (t < ca->bic_K) /* t - K */
offs = ca->bic_K - t;
- else
- offs = t - ca->bic_K;
+ else
+ offs = t - ca->bic_K;
/* c/rtt * (t-K)^3 */
delta = (cube_rtt_scale * offs * offs * offs) >> (10+3*BICTCP_HZ);
- if (t < ca->bic_K) /* below origin*/
- bic_target = ca->bic_origin_point - delta;
- else /* above origin*/
- bic_target = ca->bic_origin_point + delta;
+ if (t < ca->bic_K) /* below origin*/
+ bic_target = ca->bic_origin_point - delta;
+ else /* above origin*/
+ bic_target = ca->bic_origin_point + delta;
- /* cubic function - calc bictcp_cnt*/
- if (bic_target > cwnd) {
+ /* cubic function - calc bictcp_cnt*/
+ if (bic_target > cwnd) {
ca->cnt = cwnd / (bic_target - cwnd);
- } else {
- ca->cnt = 100 * cwnd; /* very small increment*/
- }
+ } else {
+ ca->cnt = 100 * cwnd; /* very small increment*/
+ }
if (ca->delay_min > 0) {
/* max increment = Smax * rtt / 0.1 */
@@ -219,7 +219,7 @@ static inline void bictcp_update(struct bictcp *ca, u32 cwnd)
ca->cnt = min_cnt;
}
- /* slow start and low utilization */
+ /* slow start and low utilization */
if (ca->loss_cwnd == 0) /* could be aggressive in slow start */
ca->cnt = 50;
@@ -227,9 +227,9 @@ static inline void bictcp_update(struct bictcp *ca, u32 cwnd)
if (tcp_friendliness) {
u32 scale = beta_scale;
delta = (cwnd * scale) >> 3;
- while (ca->ack_cnt > delta) { /* update tcp cwnd */
- ca->ack_cnt -= delta;
- ca->tcp_cwnd++;
+ while (ca->ack_cnt > delta) { /* update tcp cwnd */
+ ca->ack_cnt -= delta;
+ ca->tcp_cwnd++;
}
if (ca->tcp_cwnd > cwnd){ /* if bic is slower than tcp */
@@ -238,7 +238,7 @@ static inline void bictcp_update(struct bictcp *ca, u32 cwnd)
if (ca->cnt > max_cnt)
ca->cnt = max_cnt;
}
- }
+ }
ca->cnt = (ca->cnt << ACK_RATIO_SHIFT) / ca->delayed_ack;
if (ca->cnt == 0) /* cannot be zero */