/* * linux/net/sunrpc/timer.c * * Estimate RPC request round trip time. * * Based on packet round-trip and variance estimator algorithms described * in appendix A of "Congestion Avoidance and Control" by Van Jacobson * and Michael J. Karels (ACM Computer Communication Review; Proceedings * of the Sigcomm '88 Symposium in Stanford, CA, August, 1988). * * This RTT estimator is used only for RPC over datagram protocols. * * Copyright (C) 2002 Trond Myklebust */ #include #include #include #include #include #define RPC_RTO_MAX (60*HZ) #define RPC_RTO_INIT (HZ/5) #define RPC_RTO_MIN (HZ/10) /** * rpc_init_rtt - Initialize an RPC RTT estimator context * @rt: context to initialize * @timeo: initial timeout value, in jiffies * */ void rpc_init_rtt(struct rpc_rtt *rt, unsigned long timeo) { unsigned long init = 0; unsigned int i; rt->timeo = timeo; if (timeo > RPC_RTO_INIT) init = (timeo - RPC_RTO_INIT) << 3; for (i = 0; i < 5; i++) { rt->srtt[i] = init; rt->sdrtt[i] = RPC_RTO_INIT; rt->ntimeouts[i] = 0; } } EXPORT_SYMBOL_GPL(rpc_init_rtt); /** * rpc_update_rtt - Update an RPC RTT estimator context * @rt: context to update * @timer: timer array index (request type) * @m: recent actual RTT, in jiffies * * NB: When computing the smoothed RTT and standard deviation, * be careful not to produce negative intermediate results. */ void rpc_update_rtt(struct rpc_rtt *rt, unsigned int timer, long m) { long *srtt, *sdrtt; if (timer-- == 0) return; /* jiffies wrapped; ignore this one */ if (m < 0) return; if (m == 0) m = 1L; srtt = (long *)&rt->srtt[timer]; m -= *srtt >> 3; *srtt += m; if (m < 0) m = -m; sdrtt = (long *)&rt->sdrtt[timer]; m -= *sdrtt >> 2; *sdrtt += m; /* Set lower bound on the variance */ if (*sdrtt < RPC_RTO_MIN) *sdrtt = RPC_RTO_MIN; } EXPORT_SYMBOL_GPL(rpc_update_rtt); /** * rpc_calc_rto - Provide an estimated timeout value * @rt: context to use for calculation * @timer: timer array index (request type) * * Estimate RTO for an NFS RPC sent via an unreliable datagram. Use * the mean and mean deviation of RTT for the appropriate type of RPC * for frequently issued RPCs, and a fixed default for the others. * * The justification for doing "other" this way is that these RPCs * happen so infrequently that timer estimation would probably be * stale. Also, since many of these RPCs are non-idempotent, a * conservative timeout is desired. * * getattr, lookup, * read, write, commit - A+4D * other - timeo */ unsigned long rpc_calc_rto(struct rpc_rtt *rt, unsigned int timer) { unsigned long res; if (timer-- == 0) return rt->timeo; res = ((rt->srtt[timer] + 7) >> 3) + rt->sdrtt[timer]; if (res > RPC_RTO_MAX) res = RPC_RTO_MAX; return res; } EXPORT_SYMBOL_GPL(rpc_calc_rto); >irda/parameters.c
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authorSergei Shtylyov <sergei.shtylyov@cogentembedded.com>2017-01-29 15:07:34 +0300
committerDavid S. Miller <davem@davemloft.net>2017-01-30 22:05:43 -0500
commit1a0bee6c1e788218fd1d141db320db970aace7f0 (patch)
tree46c4116bc8ef4a7df718516a648597d9e21c15f1 /net/irda/parameters.c
parent63c190429020a9701b42887ac22c28f287f1762f (diff)
sh_eth: rename EESIPR bits
Since the commit b0ca2a21f769 ("sh_eth: Add support of SH7763 to sh_eth") the *enum* declaring the EESIPR bits (interrupt mask) went out of sync with the *enum* declaring the EESR bits (interrupt status) WRT bit naming and formatting. I'd like to restore the consistency by using EESIPR as the bit name prefix, renaming the *enum* to EESIPR_BIT, and (finally) renaming the bits according to the available Renesas SH77{34|63} manuals; additionally, reconstruct couple names using the EESR bit declaration above... Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/irda/parameters.c')