/* * Squashfs - a compressed read only filesystem for Linux * * Copyright (c) 2002, 2003, 2004, 2005, 2006, 2007, 2008 * Phillip Lougher * * 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, * or (at your option) any later version. * * 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, write to the Free Software * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. * * fragment.c */ /* * This file implements code to handle compressed fragments (tail-end packed * datablocks). * * Regular files contain a fragment index which is mapped to a fragment * location on disk and compressed size using a fragment lookup table. * Like everything in Squashfs this fragment lookup table is itself stored * compressed into metadata blocks. A second index table is used to locate * these. This second index table for speed of access (and because it * is small) is read at mount time and cached in memory. */ #include #include #include #include "squashfs_fs.h" #include "squashfs_fs_sb.h" #include "squashfs.h" /* * Look-up fragment using the fragment index table. Return the on disk * location of the fragment and its compressed size */ int squashfs_frag_lookup(struct super_block *sb, unsigned int fragment, u64 *fragment_block) { struct squashfs_sb_info *msblk = sb->s_fs_info; int block = SQUASHFS_FRAGMENT_INDEX(fragment); int offset = SQUASHFS_FRAGMENT_INDEX_OFFSET(fragment); u64 start_block = le64_to_cpu(msblk->fragment_index[block]); struct squashfs_fragment_entry fragment_entry; int size; size = squashfs_read_metadata(sb, &fragment_entry, &start_block, &offset, sizeof(fragment_entry)); if (size < 0) return size; *fragment_block = le64_to_cpu(fragment_entry.start_block); size = le32_to_cpu(fragment_entry.size); return size; } /* * Read the uncompressed fragment lookup table indexes off disk into memory */ __le64 *squashfs_read_fragment_index_table(struct super_block *sb, u64 fragment_table_start, u64 next_table, unsigned int fragments) { unsigned int length = SQUASHFS_FRAGMENT_INDEX_BYTES(fragments); __le64 *table; /* * Sanity check, length bytes should not extend into the next table - * this check also traps instances where fragment_table_start is * incorrectly larger than the next table start */ if (fragment_table_start + length > next_table) return ERR_PTR(-EINVAL); table = squashfs_read_table(sb, fragment_table_start, length); /* * table[0] points to the first fragment table metadata block, this * should be less than fragment_table_start */ if (!IS_ERR(table) && le64_to_cpu(table[0]) >= fragment_table_start) { kfree(table); return ERR_PTR(-EINVAL); } return table; } next.git/commit/tools/perf?h=nds-private-remove&id=6e978b22efa1db9f6e71b24440b5f1d93e968ee3'>perf/util/evsel.h
diff options
context:
space:
mode:
authorSrinivas Pandruvada <srinivas.pandruvada@linux.intel.com>2017-02-03 14:18:39 -0800
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>2017-02-04 00:11:08 +0100
commit6e978b22efa1db9f6e71b24440b5f1d93e968ee3 (patch)
treec666f7a26b860674848949e39a610222b0723f89 /tools/perf/util/evsel.h
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 'tools/perf/util/evsel.h')