An application is suspected of having memory leak when its memory
consumption is high and keeps increasing. There are several commonly used
memory allocators: slab, cma, vmalloc, etc. The memory leak
identification can be sped up if the page information allocated by an
allocator can be analyzed separately.
This patch provides supports for memory allocator labelling for slab,
vmalloc, and cma. The pages allocated by slab and cma can be confirmed
from the "PFN" line according to the kernel codes, and the label of the
vmalloc allocator can be obtained by analyzing the stack trace. Thanks
for Vlastimil Babka's constructive suggestions.
Based on Yinan Zhang's study, the call chain of vmalloc() is vmalloc() ->
... -> __vmalloc_node_range() -> __vmalloc_area_node().
__vmalloc_area_node() requests memory through the interface of buddy
allocation system. In the current version, __vmalloc_area_node() uses
four interfaces: alloc_pages_bulk_array_mempolicy(),
alloc_pages_bulk_array_node(), alloc_pages() and alloc_pages_node(). By
disassembling the code, we find that __vmalloc_area_node() is expanded in
__vmalloc_node_range(). So __vmalloc_area_node is not in the stack trace.
On the test machine, the stack trace of pages allocated by vmalloc has the
following four forms:
__alloc_pages_bulk+0x230/0x6a0
__vmalloc_node_range+0x19c/0x598
alloc_pages_bulk_array_mempolicy+0xbc/0x278
__vmalloc_node_range+0x1e8/0x598
__alloc_pages+0x160/0x2b0
__vmalloc_node_range+0x234/0x598
alloc_pages+0xac/0x150
__vmalloc_node_range+0x44c/0x598
Therefore, in two consecutive lines of stacktrace, if the first line
contains the word "alloc_pages" and the second line contains the word
"__vmalloc_node_range", it can be determined that the page is allocated by
vmalloc. And the function offset and size are not the same on different
machines, so there is no need to match them.
At the same time, this patch updates the --cull and --sort options to
support allocator-based merge statistics and sorting. The added functions
are fully compatible with the original work. When using, you can use
"allocator", or abbreviated as "ator". Relevant updates have also been
made in the documentation(Documentation/vm/page_owner.rst).
Example:
./page_owner_sort <input> <output> --cull=st,pid,name,allocator
./page_owner_sort <input> <output> --sort=ator,pid,name
This work is coauthored by Jiajian Ye, Yinan Zhang, Shenghong Han,
Chongxi Zhao, Yuhong Feng and Yongqiang Liu.
Link: https://lkml.kernel.org/r/20220410132932.9402-1-caoyixuan2019@email.szu.edu.cn
Signed-off-by: Yixuan Cao <caoyixuan2019@email.szu.edu.cn>
Cc: Chongxi Zhao <zhaochongxi2019@email.szu.edu.cn>
Cc: Haowen Bai <baihaowen@meizu.com>
Cc: Jiajian Ye <yejiajian2018@email.szu.edu.cn>
Cc: Sean Anderson <seanga2@gmail.com>
Cc: Shenghong Han <hanshenghong2019@email.szu.edu.cn>
Cc: Yinan Zhang <zhangyinan2019@email.szu.edu.cn>
Cc: Yongqiang Liu <liuyongqiang13@huawei.com>
Cc: Yuhong Feng <yuhongf@szu.edu.cn>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
When viewing page owner information, we may want to sort blocks of
information by multiple keys, since one single key does not uniquely
identify a block. Therefore, following adjustments are made:
1. Add a new --sort option to support sorting blocks of information by
multiple keys.
./page_owner_sort <input> <output> --sort=<order>
./page_owner_sort <input> <output> --sort <order>
<order> is a single argument in the form of a comma-separated list,
which offers a way to specify sorting order.
Sorting syntax is [+|-]key[,[+|-]key[,...]]. The ascending or descending
order can be specified by adding the + (ascending, default) or - (descend
-ing) prefix to the key:
./page_owner_sort <input> <output> [option] --sort -key1,+key2,key3...
For example, to sort the blocks first by task command name in lexicographic
order and then by pid in ascending numerical order, use the following:
./page_owner_sort <input> <output> --sort=name,+pid
To sort the blocks first by pid in ascending order and then by timestamp
of the page when it is allocated in descending order, use the following:
./page_owner_sort <input> <output> --sort=pid,-alloc_ts
2. Add explanations of a newly added --sort option in the function usage()
and the document(Documentation/vm/page_owner.rst).
This work is coauthored by
Yixuan Cao
Shenghong Han
Yinan Zhang
Chongxi Zhao
Yuhong Feng
Yongqiang Liu
Link: https://lkml.kernel.org/r/20220401024856.767-3-yejiajian2018@email.szu.edu.cn
Signed-off-by: Jiajian Ye <yejiajian2018@email.szu.edu.cn>
Cc: Chongxi Zhao <zhaochongxi2019@email.szu.edu.cn>
Cc: Shenghong Han <hanshenghong2019@email.szu.edu.cn>
Cc: Yinan Zhang <zhangyinan2019@email.szu.edu.cn>
Cc: Yixuan Cao <caoyixuan2019@email.szu.edu.cn>
Cc: Yongqiang Liu <liuyongqiang13@huawei.com>
Cc: Yuhong Feng <yuhongf@szu.edu.cn>
Cc: Haowen Bai <baihaowen@meizu.com>
Cc: Sean Anderson <seanga2@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
When viewing page owner information, we may want to select blocks whose
PID/TGID/TASK_COMM_NAME appears in a user-specified list for data analysis
and aggregation. But currently page_owner_sort only supports selecting
blocks associated with only one specified PID/TGID/TASK_COMM_NAME.
Therefore, following adjustments are made to fix the problem:
1. Enhance selecting function to support the selection of multiple
PIDs/TGIDs/TASK_COMM_NAMEs.
The enhanced usages are as follows:
--pid <pidlist> Select by pid. This selects the blocks whose PID
numbers appear in <pidlist>.
--tgid <tgidlist> Select by tgid. This selects the blocks whose
TGID numbers appear in <tgidlist>.
--name <cmdlist> Select by task command name. This selects the
blocks whose task command name appear in <cmdlist>.
Where <pidlist>, <tgidlist>, <cmdlist> are single arguments in the form of
a comma-separated list,which offers a way to specify individual selecting
rules.
For example, if you want to select blocks whose tgids are 1, 2 or 3, you
have to use 4 commands as follows:
./page_owner_sort <input> <output1> --tgid=1
./page_owner_sort <input> <output2> --tgid=2
./page_owner_sort <input> <output3> --tgid=3
cat <output1> <output2> <output3> > <output>
With this patch, you can use only 1 command to obtain the same result as
above:
./page_owner_sort <input> <output1> --tgid=1,2,3
2. Update explanations of --pid, --tgid and --name in the function
usage() and the document(Documents/vm/page_owner.rst).
This work is coauthored by
Yixuan Cao
Shenghong Han
Yinan Zhang
Chongxi Zhao
Yuhong Feng
Yongqiang Liu
Link: https://lkml.kernel.org/r/20220401024856.767-2-yejiajian2018@email.szu.edu.cn
Signed-off-by: Jiajian Ye <yejiajian2018@email.szu.edu.cn>
Cc: Chongxi Zhao <zhaochongxi2019@email.szu.edu.cn>
Cc: Shenghong Han <hanshenghong2019@email.szu.edu.cn>
Cc: Yinan Zhang <zhangyinan2019@email.szu.edu.cn>
Cc: Yixuan Cao <caoyixuan2019@email.szu.edu.cn>
Cc: Yongqiang Liu <liuyongqiang13@huawei.com>
Cc: Yuhong Feng <yuhongf@szu.edu.cn>
Cc: Haowen Bai <baihaowen@meizu.com>
Cc: Sean Anderson <seanga2@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
When viewing page owner information, we may want to cull blocks of
information with our own rules. So it is important to enhance culling
function to provide the support for customizing culling rules.
Therefore, following adjustments are made:
1. Add --cull option to support the culling of blocks of information
with user-defined culling rules.
./page_owner_sort <input> <output> --cull=<rules>
./page_owner_sort <input> <output> --cull <rules>
<rules> is a single argument in the form of a comma-separated list to
specify individual culling rules, by the sequence of keys k1,k2, ....
Mixed use of abbreviated and complete-form of keys is allowed.
For reference, please see the document(Documentation/vm/page_owner.rst).
Now, assuming two blocks in the input file are as follows:
Page allocated via order 0, mask xxxx, pid 1, tgid 1 (task_name_demo)
PFN xxxx
prep_new_page+0xd0/0xf8
get_page_from_freelist+0x4a0/0x1290
__alloc_pages+0x168/0x340
alloc_pages+0xb0/0x158
Page allocated via order 0, mask xxxx, pid 32, tgid 32 (task_name_demo)
PFN xxxx
prep_new_page+0xd0/0xf8
get_page_from_freelist+0x4a0/0x1290
__alloc_pages+0x168/0x340
alloc_pages+0xb0/0x158
If we want to cull the blocks by stacktrace and task command name, we can
use this command:
./page_owner_sort <input> <output> --cull=stacktrace,name
The output would be like:
2 times, 2 pages, task_comm_name: task_name_demo
prep_new_page+0xd0/0xf8
get_page_from_freelist+0x4a0/0x1290
__alloc_pages+0x168/0x340
alloc_pages+0xb0/0x158
As we can see, these two blocks are culled successfully, for they share
the same pid and task command name.
However, if we want to cull the blocks by pid, stacktrace and task command
name, we can this command:
./page_owner_sort <input> <output> --cull=stacktrace,name,pid
The output would be like:
1 times, 1 pages, PID 1, task_comm_name: task_name_demo
prep_new_page+0xd0/0xf8
get_page_from_freelist+0x4a0/0x1290
__alloc_pages+0x168/0x340
alloc_pages+0xb0/0x158
1 times, 1 pages, PID 32, task_comm_name: task_name_demo
prep_new_page+0xd0/0xf8
get_page_from_freelist+0x4a0/0x1290
__alloc_pages+0x168/0x340
alloc_pages+0xb0/0x158
As we can see, these two blocks are failed to cull, for their PIDs are
different.
2. Add explanations of --cull options to the document.
This work is coauthored by
Yixuan Cao
Shenghong Han
Yinan Zhang
Chongxi Zhao
Yuhong Feng
Link: https://lkml.kernel.org/r/20220312145834.624-1-yejiajian2018@email.szu.edu.cn
Signed-off-by: Jiajian Ye <yejiajian2018@email.szu.edu.cn>
Cc: Yixuan Cao <caoyixuan2019@email.szu.edu.cn>
Cc: Shenghong Han <hanshenghong2019@email.szu.edu.cn>
Cc: Yinan Zhang <zhangyinan2019@email.szu.edu.cn>
Cc: Chongxi Zhao <zhaochongxi2019@email.szu.edu.cn>
Cc: Yuhong Feng <yuhongf@szu.edu.cn>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Sean Anderson <seanga2@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When viewing page owner information, we may also need to select the blocks
by PID, TGID or task command name, which helps to get more accurate page
allocation information as needed.
Therefore, following adjustments are made:
1. Add three new options, including --pid, --tgid and --name, to support
the selection of information blocks by a specific pid, tgid and task
command name. In addtion, multiple options are allowed to be used at
the same time.
./page_owner_sort [input] [output] --pid <PID>
./page_owner_sort [input] [output] --tgid <TGID>
./page_owner_sort [input] [output] --name <TASK_COMMAND_NAME>
Assuming a scenario when a multi-threaded program, ./demo (PID =
5280), is running, and ./demo creates a child process (PID = 5281).
$ps
PID TTY TIME CMD
5215 pts/0 00:00:00 bash
5280 pts/0 00:00:00 ./demo
5281 pts/0 00:00:00 ./demo
5282 pts/0 00:00:00 ps
It would be better to filter out the records with tgid=5280 and the
task name "demo" when debugging the parent process, and the specific
usage is
./page_owner_sort [input] [output] --tgid 5280 --name demo
2. Add explanations of three new options, including --pid, --tgid and
--name, to the document.
This work is coauthored by
Shenghong Han <hanshenghong2019@email.szu.edu.cn>,
Yixuan Cao <caoyixuan2019@email.szu.edu.cn>,
Yinan Zhang <zhangyinan2019@email.szu.edu.cn>,
Chongxi Zhao <zhaochongxi2019@email.szu.edu.cn>,
Yuhong Feng <yuhongf@szu.edu.cn>.
Link: https://lkml.kernel.org/r/1646835223-7584-1-git-send-email-yejiajian2018@email.szu.edu.cn
Signed-off-by: Jiajian Ye <yejiajian2018@email.szu.edu.cn>
Cc: Sean Anderson <seanga2@gmail.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Zhenliang Wei <weizhenliang@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When viewing the page owner information, we expect that the information
can be sorted by PID, so that we can quickly combine PID with the program
to check the information together.
We also expect that the information can be sorted by time. Time sorting
helps to view the running status of the program according to the time
interval when the program hangs up.
Finally, we hope to pass the page_ owner_ Sort. C can reduce part of the
output and only output the plate information whose memory has not been
released, which can make us locate the problem of the program faster.
Therefore, the following adjustments have been made:
1. Add the static functions search_pattern and check_regcomp to
improve the cleanliness.
2. Add member attributes and their corresponding sorting methods. In
terms of comparison time, int will overflow because the data of ull is
too large, so the ternary operator is used
3. Add the -f parameter to filter out the information of blocks whose
memory has not been released
Link: https://lkml.kernel.org/r/20211206165653.5093-1-zhaochongxi2019@email.szu.edu.cn
Signed-off-by: Chongxi Zhao <zhaochongxi2019@email.szu.edu.cn>
Reviewed-by: Sean Anderson <seanga2@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Culling by comparing stacktrace would casue loss of some information. For
example, if there exists 2 blocks which have the same stacktrace and the
different head info
Page allocated via order 0, mask 0x108c48(...), pid 73696,
ts 1578829190639010 ns, free_ts 1576583851324450 ns
prep_new_page+0x80/0xb8
get_page_from_freelist+0x924/0xee8
__alloc_pages+0x138/0xc18
alloc_pages+0x80/0xf0
__page_cache_alloc+0x90/0xc8
Page allocated via order 0, mask 0x108c48(...), pid 61806,
ts 1354113726046100 ns, free_ts 1354104926841400 ns
prep_new_page+0x80/0xb8
get_page_from_freelist+0x924/0xee8
__alloc_pages+0x138/0xc18
alloc_pages+0x80/0xf0
__page_cache_alloc+0x90/0xc8
After culling, it would be like this
2 times, 2 pages:
Page allocated via order 0, mask 0x108c48(...), pid 73696,
ts 1578829190639010 ns, free_ts 1576583851324450 ns
prep_new_page+0x80/0xb8
get_page_from_freelist+0x924/0xee8
__alloc_pages+0x138/0xc18
alloc_pages+0x80/0xf0
__page_cache_alloc+0x90/0xc8
The info of second block missed. So, add -c to turn on culling by
stacktrace. By default, it will cull by txt.
Link: https://lkml.kernel.org/r/20211129145658.2491-1-zhangyinan2019@email.szu.edu.cn
Signed-off-by: Yinan Zhang <zhangyinan2019@email.szu.edu.cn>
Cc: Changhee Han <ch0.han@lge.com>
Cc: Sean Anderson <seanga2@gmail.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Tang Bin <tangbin@cmss.chinamobile.com>
Cc: Zhang Shengju <zhangshengju@cmss.chinamobile.com>
Cc: Zhenliang Wei <weizhenliang@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When viewing page owner information, we may be more concerned about the
total memory rather than the times of stack appears. Therefore, the
following adjustments are made:
1. Added the statistics on the total number of pages.
2. Added the optional parameter "-m" to configure the program to sort by
memory (total pages).
The general output of page_owner is as follows:
Page allocated via order XXX, ...
PFN XXX ...
// Detailed stack
Page allocated via order XXX, ...
PFN XXX ...
// Detailed stack
The original page_owner_sort ignores PFN rows, puts the remaining rows
in buf, counts the times of buf, and finally sorts them according to the
times. General output:
XXX times:
Page allocated via order XXX, ...
// Detailed stack
Now, we use regexp to extract the page order value from the buf, and
count the total pages for the buf. General output:
XXX times, XXX pages:
Page allocated via order XXX, ...
// Detailed stack
By default, it is still sorted by the times of buf; If you want to sort
by the pages nums of buf, use the new -m parameter.
Link: https://lkml.kernel.org/r/1631678242-41033-1-git-send-email-weizhenliang@huawei.com
Signed-off-by: Zhenliang Wei <weizhenliang@huawei.com>
Cc: Tang Bin <tangbin@cmss.chinamobile.com>
Cc: Zhang Shengju <zhangshengju@cmss.chinamobile.com>
Cc: Zhenliang Wei <weizhenliang@huawei.com>
Cc: Xiaoming Ni <nixiaoming@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Idle page tracking can also be used for process address space, not only
file mappings.
Without this change, using with '-i' option for process address space
encounters below errors reported.
$ sudo ./page-types -p $(pidof bash) -i
mark page idle: Bad file descriptor
mark page idle: Bad file descriptor
mark page idle: Bad file descriptor
mark page idle: Bad file descriptor
...
Link: https://lkml.kernel.org/r/20210917032826.10669-1-changbin.du@gmail.com
Signed-off-by: Changbin Du <changbin.du@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
For arm64 MTE support it is necessary to be able to mark pages that
contain user space visible tags that will need to be saved/restored e.g.
when swapped out.
To support this add a new arch specific flag (PG_arch_2). This flag is
only available on 64-bit architectures due to the limited number of
spare page flags on the 32-bit ones.
Signed-off-by: Steven Price <steven.price@arm.com>
[catalin.marinas@arm.com: use CONFIG_64BIT for guarding this new flag]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
During recent discussion on LKML over SLAB vs SLUB it was suggested by
Jesper that it would be nice to have a tool to view the current
fragmentation of the slab allocators. CC list for this set is taken
from that thread.
For SLUB we have all the information for this already exposed by the
kernel and also we have a userspace tool for displaying this info:
tools/vm/slabinfo.c
Extend slabinfo to improve the fragmentation information by enabling
sorting of caches by number of partial slabs.
Also add cache list sorted in this manner to the output of `slabinfo -X`.
This patch (of 4):
get_opt() has a spurious character within the option string. Remove it
and reorder the options in alphabetic order so that it is easier to keep
the options correct. Use the same ordering for command help output and
long option handling code.
Link: http://lkml.kernel.org/r/20190426022622.4089-2-tobin@kernel.org
Signed-off-by: Tobin C. Harding <tobin@kernel.org>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Cc: Pekka Enberg <penberg@iki.fi>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Qian Cai <cai@lca.pw>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Alexander Duyck <alexander.duyck@gmail.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>,
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Based on 1 normalized pattern(s):
this software is licensed under the terms of the gnu general public
license version 2 as published by the free software foundation and
may be copied distributed and modified under those terms 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
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 285 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190529141900.642774971@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Based on 1 normalized pattern(s):
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 version 2 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 find a copy of v2 of the gnu general public
license somewhere on your linux system if not write to the free
software foundation inc 59 temple place suite 330 boston ma 02111
1307 usa
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 1 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190529141900.073926682@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add a new flag that will read kpagecount for each PFN and print out the
number of times the page is mapped along with the flags in the listing
view.
This information is useful in understanding and optimizing memory usage.
Identifying pages which are not shared allows us to focus on adjusting
the memory layout or access patterns for the sole owning process.
Knowing the number of processes that share a page tells us how many
other times we must make the same adjustments or how many processes to
potentially disable.
Truncated sample output:
voffset map-cnt offset len flags
561a3591e 1 15fe8 1 ___U_lA____Ma_b___________________________
561a3591f 1 2b103 1 ___U_lA____Ma_b___________________________
561a36ca4 1 2cc78 1 ___U_lA____Ma_b___________________________
7f588bb4e 14 2273c 1 __RU_lA____M______________________________
[akpm@linux-foundation.org: coding-style fixes]
[chansen3@cisco.com: add documentation, tweak whitespace]
Link: http://lkml.kernel.org/r/20180705181204.5529-1-chansen3@cisco.com
Link: http://lkml.kernel.org/r/20180612153205.12879-1-chansen3@cisco.com
Signed-off-by: Christian Hansen <chansen3@cisco.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently a number of Makefiles break when used with toolchains that
pass extra flags in CC and other cross-compile related variables (such
as --sysroot).
Thus we get this error when we use a toolchain that puts --sysroot in
the CC var:
~/src/linux/tools$ make iio
[snip]
iio_event_monitor.c:18:10: fatal error: unistd.h: No such file or directory
#include <unistd.h>
^~~~~~~~~~
This occurs because we clobber several env vars related to
cross-compiling with lines like this:
CC = $(CROSS_COMPILE)gcc
Although this will point to a valid cross-compiler, we lose any extra
flags that might exist in the CC variable, which can break toolchains
that rely on them (for example, those that use --sysroot).
This easily shows up using a Yocto SDK:
$ . [snip]/sdk/environment-setup-cortexa8hf-neon-poky-linux-gnueabi
$ echo $CC
arm-poky-linux-gnueabi-gcc -march=armv7-a -mfpu=neon -mfloat-abi=hard
-mcpu=cortex-a8
--sysroot=[snip]/sdk/sysroots/cortexa8hf-neon-poky-linux-gnueabi
$ echo $CROSS_COMPILE
arm-poky-linux-gnueabi-
$ echo ${CROSS_COMPILE}gcc
krm-poky-linux-gnueabi-gcc
Although arm-poky-linux-gnueabi-gcc is a cross-compiler, we've lost the
--sysroot and other flags that enable us to find the right libraries to
link against, so we can't find unistd.h and other libraries and headers.
Normally with the --sysroot flag we would find unistd.h in the sdk
directory in the sysroot:
$ find [snip]/sdk/sysroots -path '*/usr/include/unistd.h'
[snip]/sdk/sysroots/cortexa8hf-neon-poky-linux-gnueabi/usr/include/unistd.h
The perf Makefile adds CC = $(CROSS_COMPILE)gcc if and only if CC is not
already set, and it compiles correctly with the above toolchain.
So, generalize the logic that perf uses in the common Makefile and
remove the manual CC = $(CROSS_COMPILE)gcc lines from each Makefile.
Note that this patch does not fix cross-compile for all the tools (some
have other bugs), but it does fix it for all except usb and acpi, which
still have other unrelated issues.
I tested both with and without the patch on native and cross-build and
there appear to be no regressions.
Link: http://lkml.kernel.org/r/20180107214028.23771-1-martin@martingkelly.com
Signed-off-by: Martin Kelly <martin@martingkelly.com>
Acked-by: Mark Brown <broonie@kernel.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Li Zefan <lizefan@huawei.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Jonathan Cameron <jic23@kernel.org>
Cc: Pali Rohar <pali.rohar@gmail.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Jacek Anaszewski <jacek.anaszewski@gmail.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Robert Moore <robert.moore@intel.com>
Cc: Lv Zheng <lv.zheng@intel.com>
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Valentina Manea <valentina.manea.m@gmail.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Mario Limonciello <mario.limonciello@dell.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
