/* Copyright (C) 2006-2017 B.A.T.M.A.N. contributors: * * Simon Wunderlich, Marek Lindner * * This program is free software; you can redistribute it and/or * modify it under the terms of version 2 of the GNU General Public * License as published by the Free Software Foundation. * * This program is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, see . */ #include "bitarray.h" #include "main.h" #include #include "log.h" /* shift the packet array by n places. */ static void batadv_bitmap_shift_left(unsigned long *seq_bits, s32 n) { if (n <= 0 || n >= BATADV_TQ_LOCAL_WINDOW_SIZE) return; bitmap_shift_left(seq_bits, seq_bits, n, BATADV_TQ_LOCAL_WINDOW_SIZE); } /** * batadv_bit_get_packet - receive and process one packet within the sequence * number window * @priv: the bat priv with all the soft interface information * @seq_bits: pointer to the sequence number receive packet * @seq_num_diff: difference between the current/received sequence number and * the last sequence number * @set_mark: whether this packet should be marked in seq_bits * * Return: true if the window was moved (either new or very old), * false if the window was not moved/shifted. */ bool batadv_bit_get_packet(void *priv, unsigned long *seq_bits, s32 seq_num_diff, int set_mark) { struct batadv_priv *bat_priv = priv; /* sequence number is slightly older. We already got a sequence number * higher than this one, so we just mark it. */ if (seq_num_diff <= 0 && seq_num_diff > -BATADV_TQ_LOCAL_WINDOW_SIZE) { if (set_mark) batadv_set_bit(seq_bits, -seq_num_diff); return false; } /* sequence number is slightly newer, so we shift the window and * set the mark if required */ if (seq_num_diff > 0 && seq_num_diff < BATADV_TQ_LOCAL_WINDOW_SIZE) { batadv_bitmap_shift_left(seq_bits, seq_num_diff); if (set_mark) batadv_set_bit(seq_bits, 0); return true; } /* sequence number is much newer, probably missed a lot of packets */ if (seq_num_diff >= BATADV_TQ_LOCAL_WINDOW_SIZE && seq_num_diff < BATADV_EXPECTED_SEQNO_RANGE) { batadv_dbg(BATADV_DBG_BATMAN, bat_priv, "We missed a lot of packets (%i) !\n", seq_num_diff - 1); bitmap_zero(seq_bits, BATADV_TQ_LOCAL_WINDOW_SIZE); if (set_mark) batadv_set_bit(seq_bits, 0); return true; } /* received a much older packet. The other host either restarted * or the old packet got delayed somewhere in the network. The * packet should be dropped without calling this function if the * seqno window is protected. * * seq_num_diff <= -BATADV_TQ_LOCAL_WINDOW_SIZE * or * seq_num_diff >= BATADV_EXPECTED_SEQNO_RANGE */ batadv_dbg(BATADV_DBG_BATMAN, bat_priv, "Other host probably restarted!\n"); bitmap_zero(seq_bits, BATADV_TQ_LOCAL_WINDOW_SIZE); if (set_mark) batadv_set_bit(seq_bits, 0); return true; } 421a4ca76468'/>
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authorThomas Gleixner <tglx@linutronix.de>2017-01-31 23:58:38 +0100
committerIngo Molnar <mingo@kernel.org>2017-02-01 08:37:27 +0100
commitdd86e373e09fb16b83e8adf5c48c421a4ca76468 (patch)
tree55703c2ea8584e303e342090614e0aab3509ab21 /net/core/scm.c
parent0b3589be9b98994ce3d5aeca52445d1f5627c4ba (diff)
perf/x86/intel/rapl: Make package handling more robust
The package management code in RAPL relies on package mapping being available before a CPU is started. This changed with: 9d85eb9119f4 ("x86/smpboot: Make logical package management more robust") because the ACPI/BIOS information turned out to be unreliable, but that left RAPL in broken state. This was not noticed because on a regular boot all CPUs are online before RAPL is initialized. A possible fix would be to reintroduce the mess which allocates a package data structure in CPU prepare and when it turns out to already exist in starting throw it away later in the CPU online callback. But that's a horrible hack and not required at all because RAPL becomes functional for perf only in the CPU online callback. That's correct because user space is not yet informed about the CPU being onlined, so nothing caan rely on RAPL being available on that particular CPU. Move the allocation to the CPU online callback and simplify the hotplug handling. At this point the package mapping is established and correct. This also adds a missing check for available package data in the event_init() function. Reported-by: Yasuaki Ishimatsu <yasu.isimatu@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sebastian Siewior <bigeasy@linutronix.de> Cc: Stephane Eranian <eranian@google.com> Cc: Vince Weaver <vincent.weaver@maine.edu> Fixes: 9d85eb9119f4 ("x86/smpboot: Make logical package management more robust") Link: http://lkml.kernel.org/r/20170131230141.212593966@linutronix.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'net/core/scm.c')