/* * 6LoWPAN next header compression * * * Authors: * Alexander Aring * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version * 2 of the License, or (at your option) any later version. */ #include #include #include "nhc.h" static struct rb_root rb_root = RB_ROOT; static struct lowpan_nhc *lowpan_nexthdr_nhcs[NEXTHDR_MAX]; static DEFINE_SPINLOCK(lowpan_nhc_lock); static int lowpan_nhc_insert(struct lowpan_nhc *nhc) { struct rb_node **new = &rb_root.rb_node, *parent = NULL; /* Figure out where to put new node */ while (*new) { struct lowpan_nhc *this = rb_entry(*new, struct lowpan_nhc, node); int result, len_dif, len; len_dif = nhc->idlen - this->idlen; if (nhc->idlen < this->idlen) len = nhc->idlen; else len = this->idlen; result = memcmp(nhc->id, this->id, len); if (!result) result = len_dif; parent = *new; if (result < 0) new = &((*new)->rb_left); else if (result > 0) new = &((*new)->rb_right); else return -EEXIST; } /* Add new node and rebalance tree. */ rb_link_node(&nhc->node, parent, new); rb_insert_color(&nhc->node, &rb_root); return 0; } static void lowpan_nhc_remove(struct lowpan_nhc *nhc) { rb_erase(&nhc->node, &rb_root); } static struct lowpan_nhc *lowpan_nhc_by_nhcid(const struct sk_buff *skb) { struct rb_node *node = rb_root.rb_node; const u8 *nhcid_skb_ptr = skb->data; while (node) { struct lowpan_nhc *nhc = rb_entry(node, struct lowpan_nhc, node); u8 nhcid_skb_ptr_masked[LOWPAN_NHC_MAX_ID_LEN]; int result, i; if (nhcid_skb_ptr + nhc->idlen > skb->data + skb->len) return NULL; /* copy and mask afterwards the nhid value from skb */ memcpy(nhcid_skb_ptr_masked, nhcid_skb_ptr, nhc->idlen); for (i = 0; i < nhc->idlen; i++) nhcid_skb_ptr_masked[i] &= nhc->idmask[i]; result = memcmp(nhcid_skb_ptr_masked, nhc->id, nhc->idlen); if (result < 0) node = node->rb_left; else if (result > 0) node = node->rb_right; else return nhc; } return NULL; } int lowpan_nhc_check_compression(struct sk_buff *skb, const struct ipv6hdr *hdr, u8 **hc_ptr) { struct lowpan_nhc *nhc; int ret = 0; spin_lock_bh(&lowpan_nhc_lock); nhc = lowpan_nexthdr_nhcs[hdr->nexthdr]; if (!(nhc && nhc->compress)) ret = -ENOENT; spin_unlock_bh(&lowpan_nhc_lock); return ret; } int lowpan_nhc_do_compression(struct sk_buff *skb, const struct ipv6hdr *hdr, u8 **hc_ptr) { int ret; struct lowpan_nhc *nhc; spin_lock_bh(&lowpan_nhc_lock); nhc = lowpan_nexthdr_nhcs[hdr->nexthdr]; /* check if the nhc module was removed in unlocked part. * TODO: this is a workaround we should prevent unloading * of nhc modules while unlocked part, this will always drop * the lowpan packet but it's very unlikely. * * Solution isn't easy because we need to decide at * lowpan_nhc_check_compression if we do a compression or not. * Because the inline data which is added to skb, we can't move this * handling. */ if (unlikely(!nhc || !nhc->compress)) { ret = -EINVAL; goto out; } /* In the case of RAW sockets the transport header is not set by * the ip6 stack so we must set it ourselves */ if (skb->transport_header == skb->network_header) skb_set_transport_header(skb, sizeof(struct ipv6hdr)); ret = nhc->compress(skb, hc_ptr); if (ret < 0) goto out; /* skip the transport header */ skb_pull(skb, nhc->nexthdrlen); out: spin_unlock_bh(&lowpan_nhc_lock); return ret; } int lowpan_nhc_do_uncompression(struct sk_buff *skb, const struct net_device *dev, struct ipv6hdr *hdr) { struct lowpan_nhc *nhc; int ret; spin_lock_bh(&lowpan_nhc_lock); nhc = lowpan_nhc_by_nhcid(skb); if (nhc) { if (nhc->uncompress) { ret = nhc->uncompress(skb, sizeof(struct ipv6hdr) + nhc->nexthdrlen); if (ret < 0) { spin_unlock_bh(&lowpan_nhc_lock); return ret; } } else { spin_unlock_bh(&lowpan_nhc_lock); netdev_warn(dev, "received nhc id for %s which is not implemented.\n", nhc->name); return -ENOTSUPP; } } else { spin_unlock_bh(&lowpan_nhc_lock); netdev_warn(dev, "received unknown nhc id which was not found.\n"); return -ENOENT; } hdr->nexthdr = nhc->nexthdr; skb_reset_transport_header(skb); raw_dump_table(__func__, "raw transport header dump", skb_transport_header(skb), nhc->nexthdrlen); spin_unlock_bh(&lowpan_nhc_lock); return 0; } int lowpan_nhc_add(struct lowpan_nhc *nhc) { int ret; if (!nhc->idlen || !nhc->idsetup) return -EINVAL; WARN_ONCE(nhc->idlen > LOWPAN_NHC_MAX_ID_LEN, "LOWPAN_NHC_MAX_ID_LEN should be updated to %zd.\n", nhc->idlen); nhc->idsetup(nhc); spin_lock_bh(&lowpan_nhc_lock); if (lowpan_nexthdr_nhcs[nhc->nexthdr]) { ret = -EEXIST; goto out; } ret = lowpan_nhc_insert(nhc); if (ret < 0) goto out; lowpan_nexthdr_nhcs[nhc->nexthdr] = nhc; out: spin_unlock_bh(&lowpan_nhc_lock); return ret; } EXPORT_SYMBOL(lowpan_nhc_add); void lowpan_nhc_del(struct lowpan_nhc *nhc) { spin_lock_bh(&lowpan_nhc_lock); lowpan_nhc_remove(nhc); lowpan_nexthdr_nhcs[nhc->nexthdr] = NULL; spin_unlock_bh(&lowpan_nhc_lock); synchronize_net(); } EXPORT_SYMBOL(lowpan_nhc_del); a1db9f6e71b24440b5f1d93e968ee3'>net/caif/cfvidl.c parent3c223c19aea85d3dda1416c187915f4a30b04b1f (diff)
cpufreq: intel_pstate: Disable energy efficiency optimization
Some Kabylake desktop processors may not reach max turbo when running in HWP mode, even if running under sustained 100% utilization. This occurs when the HWP.EPP (Energy Performance Preference) is set to "balance_power" (0x80) -- the default on most systems. It occurs because the platform BIOS may erroneously enable an energy-efficiency setting -- MSR_IA32_POWER_CTL BIT-EE, which is not recommended to be enabled on this SKU. On the failing systems, this BIOS issue was not discovered when the desktop motherboard was tested with Windows, because the BIOS also neglects to provide the ACPI/CPPC table, that Windows requires to enable HWP, and so Windows runs in legacy P-state mode, where this setting has no effect. Linux' intel_pstate driver does not require ACPI/CPPC to enable HWP, and so it runs in HWP mode, exposing this incorrect BIOS configuration. There are several ways to address this problem. First, Linux can also run in legacy P-state mode on this system. As intel_pstate is how Linux enables HWP, booting with "intel_pstate=disable" will run in acpi-cpufreq/ondemand legacy p-state mode. Or second, the "performance" governor can be used with intel_pstate, which will modify HWP.EPP to 0. Or third, starting in 4.10, the /sys/devices/system/cpu/cpufreq/policy*/energy_performance_preference attribute in can be updated from "balance_power" to "performance". Or fourth, apply this patch, which fixes the erroneous setting of MSR_IA32_POWER_CTL BIT_EE on this model, allowing the default configuration to function as designed. Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Reviewed-by: Len Brown <len.brown@intel.com> Cc: 4.6+ <stable@vger.kernel.org> # 4.6+ Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'net/caif/cfvidl.c')