/* net/atm/atm_misc.c - Various functions for use by ATM drivers */ /* Written 1995-2000 by Werner Almesberger, EPFL ICA */ #include #include #include #include #include #include #include #include int atm_charge(struct atm_vcc *vcc, int truesize) { atm_force_charge(vcc, truesize); if (atomic_read(&sk_atm(vcc)->sk_rmem_alloc) <= sk_atm(vcc)->sk_rcvbuf) return 1; atm_return(vcc, truesize); atomic_inc(&vcc->stats->rx_drop); return 0; } EXPORT_SYMBOL(atm_charge); struct sk_buff *atm_alloc_charge(struct atm_vcc *vcc, int pdu_size, gfp_t gfp_flags) { struct sock *sk = sk_atm(vcc); int guess = SKB_TRUESIZE(pdu_size); atm_force_charge(vcc, guess); if (atomic_read(&sk->sk_rmem_alloc) <= sk->sk_rcvbuf) { struct sk_buff *skb = alloc_skb(pdu_size, gfp_flags); if (skb) { atomic_add(skb->truesize-guess, &sk->sk_rmem_alloc); return skb; } } atm_return(vcc, guess); atomic_inc(&vcc->stats->rx_drop); return NULL; } EXPORT_SYMBOL(atm_alloc_charge); /* * atm_pcr_goal returns the positive PCR if it should be rounded up, the * negative PCR if it should be rounded down, and zero if the maximum available * bandwidth should be used. * * The rules are as follows (* = maximum, - = absent (0), x = value "x", * (x+ = x or next value above x, x- = x or next value below): * * min max pcr result min max pcr result * - - - * (UBR only) x - - x+ * - - * * x - * * * - - z z- x - z z- * - * - * x * - x+ * - * * * x * * * * - * z z- x * z z- * - y - y- x y - x+ * - y * y- x y * y- * - y z z- x y z z- * * All non-error cases can be converted with the following simple set of rules: * * if pcr == z then z- * else if min == x && pcr == - then x+ * else if max == y then y- * else * */ int atm_pcr_goal(const struct atm_trafprm *tp) { if (tp->pcr && tp->pcr != ATM_MAX_PCR) return -tp->pcr; if (tp->min_pcr && !tp->pcr) return tp->min_pcr; if (tp->max_pcr != ATM_MAX_PCR) return -tp->max_pcr; return 0; } EXPORT_SYMBOL(atm_pcr_goal); void sonet_copy_stats(struct k_sonet_stats *from, struct sonet_stats *to) { #define __HANDLE_ITEM(i) to->i = atomic_read(&from->i) __SONET_ITEMS #undef __HANDLE_ITEM } EXPORT_SYMBOL(sonet_copy_stats); void sonet_subtract_stats(struct k_sonet_stats *from, struct sonet_stats *to) { #define __HANDLE_ITEM(i) atomic_sub(to->i, &from->i) __SONET_ITEMS #undef __HANDLE_ITEM } EXPORT_SYMBOL(sonet_subtract_stats); author
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authorDexuan Cui <decui@microsoft.com>2017-01-28 11:46:02 -0700
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2017-01-31 10:59:48 +0100
commit433e19cf33d34bb6751c874a9c00980552fe508c (patch)
treece6547ef2987fbb289fa28f03536328a42781651 /net/sunrpc/svcsock.c
parent191e885a2e130e639bb0c8ee350d7047294f2ce6 (diff)
Drivers: hv: vmbus: finally fix hv_need_to_signal_on_read()
Commit a389fcfd2cb5 ("Drivers: hv: vmbus: Fix signaling logic in hv_need_to_signal_on_read()") added the proper mb(), but removed the test "prev_write_sz < pending_sz" when making the signal decision. As a result, the guest can signal the host unnecessarily, and then the host can throttle the guest because the host thinks the guest is buggy or malicious; finally the user running stress test can perceive intermittent freeze of the guest. This patch brings back the test, and properly handles the in-place consumption APIs used by NetVSC (see get_next_pkt_raw(), put_pkt_raw() and commit_rd_index()). Fixes: a389fcfd2cb5 ("Drivers: hv: vmbus: Fix signaling logic in hv_need_to_signal_on_read()") Signed-off-by: Dexuan Cui <decui@microsoft.com> Reported-by: Rolf Neugebauer <rolf.neugebauer@docker.com> Tested-by: Rolf Neugebauer <rolf.neugebauer@docker.com> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: Stephen Hemminger <sthemmin@microsoft.com> Cc: <stable@vger.kernel.org> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'net/sunrpc/svcsock.c')