diff options
author | José Pekkarinen <jose.pekkarinen@nokia.com> | 2016-04-11 10:41:07 +0300 |
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committer | José Pekkarinen <jose.pekkarinen@nokia.com> | 2016-04-13 08:17:18 +0300 |
commit | e09b41010ba33a20a87472ee821fa407a5b8da36 (patch) | |
tree | d10dc367189862e7ca5c592f033dc3726e1df4e3 /kernel/net/ipv4/tcp_dctcp.c | |
parent | f93b97fd65072de626c074dbe099a1fff05ce060 (diff) |
These changes are the raw update to linux-4.4.6-rt14. Kernel sources
are taken from kernel.org, and rt patch from the rt wiki download page.
During the rebasing, the following patch collided:
Force tick interrupt and get rid of softirq magic(I70131fb85).
Collisions have been removed because its logic was found on the
source already.
Change-Id: I7f57a4081d9deaa0d9ccfc41a6c8daccdee3b769
Signed-off-by: José Pekkarinen <jose.pekkarinen@nokia.com>
Diffstat (limited to 'kernel/net/ipv4/tcp_dctcp.c')
-rw-r--r-- | kernel/net/ipv4/tcp_dctcp.c | 26 |
1 files changed, 16 insertions, 10 deletions
diff --git a/kernel/net/ipv4/tcp_dctcp.c b/kernel/net/ipv4/tcp_dctcp.c index 4c41c1287..7e538f71f 100644 --- a/kernel/net/ipv4/tcp_dctcp.c +++ b/kernel/net/ipv4/tcp_dctcp.c @@ -204,20 +204,26 @@ static void dctcp_update_alpha(struct sock *sk, u32 flags) /* Expired RTT */ if (!before(tp->snd_una, ca->next_seq)) { - /* For avoiding denominator == 1. */ - if (ca->acked_bytes_total == 0) - ca->acked_bytes_total = 1; + u64 bytes_ecn = ca->acked_bytes_ecn; + u32 alpha = ca->dctcp_alpha; /* alpha = (1 - g) * alpha + g * F */ - ca->dctcp_alpha = ca->dctcp_alpha - - (ca->dctcp_alpha >> dctcp_shift_g) + - (ca->acked_bytes_ecn << (10U - dctcp_shift_g)) / - ca->acked_bytes_total; - if (ca->dctcp_alpha > DCTCP_MAX_ALPHA) - /* Clamp dctcp_alpha to max. */ - ca->dctcp_alpha = DCTCP_MAX_ALPHA; + alpha -= min_not_zero(alpha, alpha >> dctcp_shift_g); + if (bytes_ecn) { + /* If dctcp_shift_g == 1, a 32bit value would overflow + * after 8 Mbytes. + */ + bytes_ecn <<= (10 - dctcp_shift_g); + do_div(bytes_ecn, max(1U, ca->acked_bytes_total)); + alpha = min(alpha + (u32)bytes_ecn, DCTCP_MAX_ALPHA); + } + /* dctcp_alpha can be read from dctcp_get_info() without + * synchro, so we ask compiler to not use dctcp_alpha + * as a temporary variable in prior operations. + */ + WRITE_ONCE(ca->dctcp_alpha, alpha); dctcp_reset(tp, ca); } } |