License cleanup: add SPDX GPL-2.0 license identifier to files with no license
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.
By default all files without license information are under the default
license of the kernel, which is GPL version 2.
Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.
This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.
How this work was done:
Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,
Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.
The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.
The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.
Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).
All documentation files were explicitly excluded.
The following heuristics were used to determine which SPDX license
identifiers to apply.
- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.
For non */uapi/* files that summary was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139
and resulted in the first patch in this series.
If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930
and resulted in the second patch in this series.
- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:
SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1
and that resulted in the third patch in this series.
- when the two scanners agreed on the detected license(s), that became
the concluded license(s).
- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.
- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).
- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.
- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.
In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.
Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.
Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.
In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.
Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct
This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.
These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-01 14:07:57 +00:00
|
|
|
// SPDX-License-Identifier: GPL-2.0
|
2014-10-09 22:28:37 +00:00
|
|
|
/*
|
|
|
|
|
* mm/debug.c
|
|
|
|
|
*
|
|
|
|
|
* mm/ specific debug routines.
|
|
|
|
|
*
|
|
|
|
|
*/
|
|
|
|
|
|
2014-10-09 22:28:34 +00:00
|
|
|
#include <linux/kernel.h>
|
|
|
|
|
#include <linux/mm.h>
|
2015-04-29 18:36:05 +00:00
|
|
|
#include <linux/trace_events.h>
|
2014-10-09 22:28:34 +00:00
|
|
|
#include <linux/memcontrol.h>
|
mm, tracing: unify mm flags handling in tracepoints and printk
In tracepoints, it's possible to print gfp flags in a human-friendly
format through a macro show_gfp_flags(), which defines a translation
array and passes is to __print_flags(). Since the following patch will
introduce support for gfp flags printing in printk(), it would be nice
to reuse the array. This is not straightforward, since __print_flags()
can't simply reference an array defined in a .c file such as mm/debug.c
- it has to be a macro to allow the macro magic to communicate the
format to userspace tools such as trace-cmd.
The solution is to create a macro __def_gfpflag_names which is used both
in show_gfp_flags(), and to define the gfpflag_names[] array in
mm/debug.c.
On the other hand, mm/debug.c also defines translation tables for page
flags and vma flags, and desire was expressed (but not implemented in
this series) to use these also from tracepoints. Thus, this patch also
renames the events/gfpflags.h file to events/mmflags.h and moves the
table definitions there, using the same macro approach as for gfpflags.
This allows translating all three kinds of mm-specific flags both in
tracepoints and printk.
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Michal Hocko <mhocko@suse.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Mel Gorman <mgorman@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-15 21:55:52 +00:00
|
|
|
#include <trace/events/mmflags.h>
|
2016-03-15 21:56:18 +00:00
|
|
|
#include <linux/migrate.h>
|
2016-03-15 21:56:21 +00:00
|
|
|
#include <linux/page_owner.h>
|
2018-10-26 22:07:45 +00:00
|
|
|
#include <linux/ctype.h>
|
2014-10-09 22:28:34 +00:00
|
|
|
|
mm, printk: introduce new format string for flags
In mm we use several kinds of flags bitfields that are sometimes printed
for debugging purposes, or exported to userspace via sysfs. To make
them easier to interpret independently on kernel version and config, we
want to dump also the symbolic flag names. So far this has been done
with repeated calls to pr_cont(), which is unreliable on SMP, and not
usable for e.g. sysfs export.
To get a more reliable and universal solution, this patch extends
printk() format string for pointers to handle the page flags (%pGp),
gfp_flags (%pGg) and vma flags (%pGv). Existing users of
dump_flag_names() are converted and simplified.
It would be possible to pass flags by value instead of pointer, but the
%p format string for pointers already has extensions for various kernel
structures, so it's a good fit, and the extra indirection in a
non-critical path is negligible.
[linux@rasmusvillemoes.dk: lots of good implementation suggestions]
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Mel Gorman <mgorman@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-15 21:55:56 +00:00
|
|
|
#include "internal.h"
|
2021-11-05 20:43:32 +00:00
|
|
|
#include <trace/events/migrate.h>
|
|
|
|
|
|
|
|
|
|
/*
|
|
|
|
|
* Define EM() and EMe() so that MIGRATE_REASON from trace/events/migrate.h can
|
|
|
|
|
* be used to populate migrate_reason_names[].
|
|
|
|
|
*/
|
|
|
|
|
#undef EM
|
|
|
|
|
#undef EMe
|
|
|
|
|
#define EM(a, b) b,
|
|
|
|
|
#define EMe(a, b) b
|
mm, printk: introduce new format string for flags
In mm we use several kinds of flags bitfields that are sometimes printed
for debugging purposes, or exported to userspace via sysfs. To make
them easier to interpret independently on kernel version and config, we
want to dump also the symbolic flag names. So far this has been done
with repeated calls to pr_cont(), which is unreliable on SMP, and not
usable for e.g. sysfs export.
To get a more reliable and universal solution, this patch extends
printk() format string for pointers to handle the page flags (%pGp),
gfp_flags (%pGg) and vma flags (%pGv). Existing users of
dump_flag_names() are converted and simplified.
It would be possible to pass flags by value instead of pointer, but the
%p format string for pointers already has extensions for various kernel
structures, so it's a good fit, and the extra indirection in a
non-critical path is negligible.
[linux@rasmusvillemoes.dk: lots of good implementation suggestions]
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Mel Gorman <mgorman@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-15 21:55:56 +00:00
|
|
|
|
2018-12-28 08:35:59 +00:00
|
|
|
const char *migrate_reason_names[MR_TYPES] = {
|
2021-11-05 20:43:32 +00:00
|
|
|
MIGRATE_REASON
|
2016-03-15 21:56:18 +00:00
|
|
|
};
|
|
|
|
|
|
mm, printk: introduce new format string for flags
In mm we use several kinds of flags bitfields that are sometimes printed
for debugging purposes, or exported to userspace via sysfs. To make
them easier to interpret independently on kernel version and config, we
want to dump also the symbolic flag names. So far this has been done
with repeated calls to pr_cont(), which is unreliable on SMP, and not
usable for e.g. sysfs export.
To get a more reliable and universal solution, this patch extends
printk() format string for pointers to handle the page flags (%pGp),
gfp_flags (%pGg) and vma flags (%pGv). Existing users of
dump_flag_names() are converted and simplified.
It would be possible to pass flags by value instead of pointer, but the
%p format string for pointers already has extensions for various kernel
structures, so it's a good fit, and the extra indirection in a
non-critical path is negligible.
[linux@rasmusvillemoes.dk: lots of good implementation suggestions]
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Mel Gorman <mgorman@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-15 21:55:56 +00:00
|
|
|
const struct trace_print_flags pageflag_names[] = {
|
|
|
|
|
__def_pageflag_names,
|
|
|
|
|
{0, NULL}
|
|
|
|
|
};
|
|
|
|
|
|
2023-01-30 04:25:13 +00:00
|
|
|
const struct trace_print_flags pagetype_names[] = {
|
|
|
|
|
__def_pagetype_names,
|
|
|
|
|
{0, NULL}
|
|
|
|
|
};
|
|
|
|
|
|
mm, printk: introduce new format string for flags
In mm we use several kinds of flags bitfields that are sometimes printed
for debugging purposes, or exported to userspace via sysfs. To make
them easier to interpret independently on kernel version and config, we
want to dump also the symbolic flag names. So far this has been done
with repeated calls to pr_cont(), which is unreliable on SMP, and not
usable for e.g. sysfs export.
To get a more reliable and universal solution, this patch extends
printk() format string for pointers to handle the page flags (%pGp),
gfp_flags (%pGg) and vma flags (%pGv). Existing users of
dump_flag_names() are converted and simplified.
It would be possible to pass flags by value instead of pointer, but the
%p format string for pointers already has extensions for various kernel
structures, so it's a good fit, and the extra indirection in a
non-critical path is negligible.
[linux@rasmusvillemoes.dk: lots of good implementation suggestions]
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Mel Gorman <mgorman@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-15 21:55:56 +00:00
|
|
|
const struct trace_print_flags gfpflag_names[] = {
|
|
|
|
|
__def_gfpflag_names,
|
|
|
|
|
{0, NULL}
|
mm, tracing: unify mm flags handling in tracepoints and printk
In tracepoints, it's possible to print gfp flags in a human-friendly
format through a macro show_gfp_flags(), which defines a translation
array and passes is to __print_flags(). Since the following patch will
introduce support for gfp flags printing in printk(), it would be nice
to reuse the array. This is not straightforward, since __print_flags()
can't simply reference an array defined in a .c file such as mm/debug.c
- it has to be a macro to allow the macro magic to communicate the
format to userspace tools such as trace-cmd.
The solution is to create a macro __def_gfpflag_names which is used both
in show_gfp_flags(), and to define the gfpflag_names[] array in
mm/debug.c.
On the other hand, mm/debug.c also defines translation tables for page
flags and vma flags, and desire was expressed (but not implemented in
this series) to use these also from tracepoints. Thus, this patch also
renames the events/gfpflags.h file to events/mmflags.h and moves the
table definitions there, using the same macro approach as for gfpflags.
This allows translating all three kinds of mm-specific flags both in
tracepoints and printk.
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Michal Hocko <mhocko@suse.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Mel Gorman <mgorman@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-15 21:55:52 +00:00
|
|
|
};
|
|
|
|
|
|
mm, printk: introduce new format string for flags
In mm we use several kinds of flags bitfields that are sometimes printed
for debugging purposes, or exported to userspace via sysfs. To make
them easier to interpret independently on kernel version and config, we
want to dump also the symbolic flag names. So far this has been done
with repeated calls to pr_cont(), which is unreliable on SMP, and not
usable for e.g. sysfs export.
To get a more reliable and universal solution, this patch extends
printk() format string for pointers to handle the page flags (%pGp),
gfp_flags (%pGg) and vma flags (%pGv). Existing users of
dump_flag_names() are converted and simplified.
It would be possible to pass flags by value instead of pointer, but the
%p format string for pointers already has extensions for various kernel
structures, so it's a good fit, and the extra indirection in a
non-critical path is negligible.
[linux@rasmusvillemoes.dk: lots of good implementation suggestions]
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Mel Gorman <mgorman@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-15 21:55:56 +00:00
|
|
|
const struct trace_print_flags vmaflag_names[] = {
|
|
|
|
|
__def_vmaflag_names,
|
|
|
|
|
{0, NULL}
|
2014-10-09 22:28:34 +00:00
|
|
|
};
|
|
|
|
|
|
2024-02-27 19:23:31 +00:00
|
|
|
static void __dump_folio(struct folio *folio, struct page *page,
|
|
|
|
|
unsigned long pfn, unsigned long idx)
|
2014-10-09 22:28:34 +00:00
|
|
|
{
|
2024-02-27 19:23:31 +00:00
|
|
|
struct address_space *mapping = folio_mapping(folio);
|
2024-04-09 19:23:00 +00:00
|
|
|
int mapcount = atomic_read(&page->_mapcount);
|
2020-01-31 06:12:03 +00:00
|
|
|
char *type = "";
|
2018-07-04 00:02:53 +00:00
|
|
|
|
2024-04-09 19:23:00 +00:00
|
|
|
mapcount = page_type_has_type(mapcount) ? 0 : mapcount + 1;
|
2024-02-27 19:23:31 +00:00
|
|
|
pr_warn("page: refcount:%d mapcount:%d mapping:%p index:%#lx pfn:%#lx\n",
|
|
|
|
|
folio_ref_count(folio), mapcount, mapping,
|
|
|
|
|
folio->index + idx, pfn);
|
|
|
|
|
if (folio_test_large(folio)) {
|
mm: track mapcount of large folios in single value
Let's track the mapcount of large folios in a single value. The mapcount
of a large folio currently corresponds to the sum of the entire mapcount
and all page mapcounts.
This sum is what we actually want to know in folio_mapcount() and it is
also sufficient for implementing folio_mapped().
With PTE-mapped THP becoming more important and more widely used, we want
to avoid looping over all pages of a folio just to obtain the mapcount of
large folios. The comment "In the common case, avoid the loop when no
pages mapped by PTE" in folio_total_mapcount() does no longer hold for
mTHP that are always mapped by PTE.
Further, we are planning on using folio_mapcount() more frequently, and
might even want to remove page mapcounts for large folios in some kernel
configs. Therefore, allow for reading the mapcount of large folios
efficiently and atomically without looping over any pages.
Maintain the mapcount also for hugetlb pages for simplicity. Use the new
mapcount to implement folio_mapcount() and folio_mapped(). Make
page_mapped() simply call folio_mapped(). We can now get rid of
folio_large_is_mapped().
_nr_pages_mapped is now only used in rmap code and for debugging purposes.
Keep folio_nr_pages_mapped() around, but document that its use should be
limited to rmap internals and debugging purposes.
This change implies one additional atomic add/sub whenever
mapping/unmapping (parts of) a large folio.
As we now batch RMAP operations for PTE-mapped THP during fork(), during
unmap/zap, and when PTE-remapping a PMD-mapped THP, and we adjust the
large mapcount for a PTE batch only once, the added overhead in the common
case is small. Only when unmapping individual pages of a large folio
(e.g., during COW), the overhead might be bigger in comparison, but it's
essentially one additional atomic operation.
Note that before the new mapcount would overflow, already our refcount
would overflow: each mapping requires a folio reference. Extend the
focumentation of folio_mapcount().
Link: https://lkml.kernel.org/r/20240409192301.907377-5-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Yin Fengwei <fengwei.yin@intel.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: Hugh Dickins <hughd@google.com>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Naoya Horiguchi <nao.horiguchi@gmail.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Richard Chang <richardycc@google.com>
Cc: Rich Felker <dalias@libc.org>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-04-09 19:22:47 +00:00
|
|
|
pr_warn("head: order:%u mapcount:%d entire_mapcount:%d nr_pages_mapped:%d pincount:%d\n",
|
2024-02-27 19:23:31 +00:00
|
|
|
folio_order(folio),
|
mm: track mapcount of large folios in single value
Let's track the mapcount of large folios in a single value. The mapcount
of a large folio currently corresponds to the sum of the entire mapcount
and all page mapcounts.
This sum is what we actually want to know in folio_mapcount() and it is
also sufficient for implementing folio_mapped().
With PTE-mapped THP becoming more important and more widely used, we want
to avoid looping over all pages of a folio just to obtain the mapcount of
large folios. The comment "In the common case, avoid the loop when no
pages mapped by PTE" in folio_total_mapcount() does no longer hold for
mTHP that are always mapped by PTE.
Further, we are planning on using folio_mapcount() more frequently, and
might even want to remove page mapcounts for large folios in some kernel
configs. Therefore, allow for reading the mapcount of large folios
efficiently and atomically without looping over any pages.
Maintain the mapcount also for hugetlb pages for simplicity. Use the new
mapcount to implement folio_mapcount() and folio_mapped(). Make
page_mapped() simply call folio_mapped(). We can now get rid of
folio_large_is_mapped().
_nr_pages_mapped is now only used in rmap code and for debugging purposes.
Keep folio_nr_pages_mapped() around, but document that its use should be
limited to rmap internals and debugging purposes.
This change implies one additional atomic add/sub whenever
mapping/unmapping (parts of) a large folio.
As we now batch RMAP operations for PTE-mapped THP during fork(), during
unmap/zap, and when PTE-remapping a PMD-mapped THP, and we adjust the
large mapcount for a PTE batch only once, the added overhead in the common
case is small. Only when unmapping individual pages of a large folio
(e.g., during COW), the overhead might be bigger in comparison, but it's
essentially one additional atomic operation.
Note that before the new mapcount would overflow, already our refcount
would overflow: each mapping requires a folio reference. Extend the
focumentation of folio_mapcount().
Link: https://lkml.kernel.org/r/20240409192301.907377-5-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Yin Fengwei <fengwei.yin@intel.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: Hugh Dickins <hughd@google.com>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Naoya Horiguchi <nao.horiguchi@gmail.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Richard Chang <richardycc@google.com>
Cc: Rich Felker <dalias@libc.org>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-04-09 19:22:47 +00:00
|
|
|
folio_mapcount(folio),
|
2023-01-11 14:28:58 +00:00
|
|
|
folio_entire_mapcount(folio),
|
2023-01-11 14:28:48 +00:00
|
|
|
folio_nr_pages_mapped(folio),
|
2023-01-11 14:28:47 +00:00
|
|
|
atomic_read(&folio->_pincount));
|
2020-08-07 06:19:35 +00:00
|
|
|
}
|
2021-02-24 20:01:29 +00:00
|
|
|
|
|
|
|
|
#ifdef CONFIG_MEMCG
|
2024-02-27 19:23:31 +00:00
|
|
|
if (folio->memcg_data)
|
|
|
|
|
pr_warn("memcg:%lx\n", folio->memcg_data);
|
2021-02-24 20:01:29 +00:00
|
|
|
#endif
|
2024-02-27 19:23:31 +00:00
|
|
|
if (folio_test_ksm(folio))
|
2020-01-31 06:12:03 +00:00
|
|
|
type = "ksm ";
|
2024-02-27 19:23:31 +00:00
|
|
|
else if (folio_test_anon(folio))
|
2020-01-31 06:12:03 +00:00
|
|
|
type = "anon ";
|
2022-01-14 22:05:04 +00:00
|
|
|
else if (mapping)
|
|
|
|
|
dump_mapping(mapping);
|
mm, printk: introduce new format string for flags
In mm we use several kinds of flags bitfields that are sometimes printed
for debugging purposes, or exported to userspace via sysfs. To make
them easier to interpret independently on kernel version and config, we
want to dump also the symbolic flag names. So far this has been done
with repeated calls to pr_cont(), which is unreliable on SMP, and not
usable for e.g. sysfs export.
To get a more reliable and universal solution, this patch extends
printk() format string for pointers to handle the page flags (%pGp),
gfp_flags (%pGg) and vma flags (%pGv). Existing users of
dump_flag_names() are converted and simplified.
It would be possible to pass flags by value instead of pointer, but the
%p format string for pointers already has extensions for various kernel
structures, so it's a good fit, and the extra indirection in a
non-critical path is negligible.
[linux@rasmusvillemoes.dk: lots of good implementation suggestions]
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Mel Gorman <mgorman@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-15 21:55:56 +00:00
|
|
|
BUILD_BUG_ON(ARRAY_SIZE(pageflag_names) != __NR_PAGEFLAGS + 1);
|
2016-03-15 21:56:24 +00:00
|
|
|
|
2024-02-27 19:23:31 +00:00
|
|
|
/*
|
|
|
|
|
* Accessing the pageblock without the zone lock. It could change to
|
|
|
|
|
* "isolate" again in the meantime, but since we are just dumping the
|
|
|
|
|
* state for debugging, it should be fine to accept a bit of
|
|
|
|
|
* inaccuracy here due to racing.
|
|
|
|
|
*/
|
|
|
|
|
pr_warn("%sflags: %pGp%s\n", type, &folio->flags,
|
|
|
|
|
is_migrate_cma_folio(folio, pfn) ? " CMA" : "");
|
2024-03-21 14:24:46 +00:00
|
|
|
if (page_has_type(&folio->page))
|
2024-08-21 17:39:09 +00:00
|
|
|
pr_warn("page_type: %x\n", folio->page.page_type);
|
2023-01-30 04:25:14 +00:00
|
|
|
|
2018-12-28 08:33:42 +00:00
|
|
|
print_hex_dump(KERN_WARNING, "raw: ", DUMP_PREFIX_NONE, 32,
|
2016-12-13 00:44:35 +00:00
|
|
|
sizeof(unsigned long), page,
|
|
|
|
|
sizeof(struct page), false);
|
2024-02-27 19:23:31 +00:00
|
|
|
if (folio_test_large(folio))
|
2020-04-02 04:05:49 +00:00
|
|
|
print_hex_dump(KERN_WARNING, "head: ", DUMP_PREFIX_NONE, 32,
|
2024-02-27 19:23:31 +00:00
|
|
|
sizeof(unsigned long), folio,
|
|
|
|
|
2 * sizeof(struct page), false);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
static void __dump_page(const struct page *page)
|
|
|
|
|
{
|
|
|
|
|
struct folio *foliop, folio;
|
|
|
|
|
struct page precise;
|
|
|
|
|
unsigned long pfn = page_to_pfn(page);
|
|
|
|
|
unsigned long idx, nr_pages = 1;
|
|
|
|
|
int loops = 5;
|
|
|
|
|
|
|
|
|
|
again:
|
|
|
|
|
memcpy(&precise, page, sizeof(*page));
|
|
|
|
|
foliop = page_folio(&precise);
|
|
|
|
|
if (foliop == (struct folio *)&precise) {
|
|
|
|
|
idx = 0;
|
|
|
|
|
if (!folio_test_large(foliop))
|
|
|
|
|
goto dump;
|
|
|
|
|
foliop = (struct folio *)page;
|
|
|
|
|
} else {
|
|
|
|
|
idx = folio_page_idx(foliop, page);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
if (idx < MAX_FOLIO_NR_PAGES) {
|
|
|
|
|
memcpy(&folio, foliop, 2 * sizeof(struct page));
|
|
|
|
|
nr_pages = folio_nr_pages(&folio);
|
|
|
|
|
foliop = &folio;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
if (idx > nr_pages) {
|
|
|
|
|
if (loops-- > 0)
|
|
|
|
|
goto again;
|
|
|
|
|
pr_warn("page does not match folio\n");
|
|
|
|
|
precise.compound_head &= ~1UL;
|
|
|
|
|
foliop = (struct folio *)&precise;
|
|
|
|
|
idx = 0;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
dump:
|
|
|
|
|
__dump_folio(foliop, &precise, pfn, idx);
|
2014-10-09 22:28:34 +00:00
|
|
|
}
|
|
|
|
|
|
2024-02-27 19:23:32 +00:00
|
|
|
void dump_page(const struct page *page, const char *reason)
|
2014-10-09 22:28:34 +00:00
|
|
|
{
|
2021-06-29 02:41:13 +00:00
|
|
|
if (PagePoisoned(page))
|
|
|
|
|
pr_warn("page:%p is uninitialized and poisoned", page);
|
|
|
|
|
else
|
|
|
|
|
__dump_page(page);
|
|
|
|
|
if (reason)
|
|
|
|
|
pr_warn("page dumped because: %s\n", reason);
|
2016-03-15 21:56:21 +00:00
|
|
|
dump_page_owner(page);
|
2014-10-09 22:28:34 +00:00
|
|
|
}
|
|
|
|
|
EXPORT_SYMBOL(dump_page);
|
|
|
|
|
|
|
|
|
|
#ifdef CONFIG_DEBUG_VM
|
|
|
|
|
|
|
|
|
|
void dump_vma(const struct vm_area_struct *vma)
|
|
|
|
|
{
|
2022-09-06 19:49:06 +00:00
|
|
|
pr_emerg("vma %px start %px end %px mm %px\n"
|
2018-01-05 00:17:59 +00:00
|
|
|
"prot %lx anon_vma %px vm_ops %px\n"
|
|
|
|
|
"pgoff %lx file %px private_data %px\n"
|
2016-03-15 21:55:59 +00:00
|
|
|
"flags: %#lx(%pGv)\n",
|
2022-09-06 19:49:06 +00:00
|
|
|
vma, (void *)vma->vm_start, (void *)vma->vm_end, vma->vm_mm,
|
2014-10-09 22:28:34 +00:00
|
|
|
(unsigned long)pgprot_val(vma->vm_page_prot),
|
|
|
|
|
vma->anon_vma, vma->vm_ops, vma->vm_pgoff,
|
2016-03-15 21:55:59 +00:00
|
|
|
vma->vm_file, vma->vm_private_data,
|
|
|
|
|
vma->vm_flags, &vma->vm_flags);
|
2014-10-09 22:28:34 +00:00
|
|
|
}
|
|
|
|
|
EXPORT_SYMBOL(dump_vma);
|
|
|
|
|
|
2014-10-09 22:28:37 +00:00
|
|
|
void dump_mm(const struct mm_struct *mm)
|
|
|
|
|
{
|
2022-09-06 19:49:06 +00:00
|
|
|
pr_emerg("mm %px task_size %lu\n"
|
|
|
|
|
"mmap_base %lu mmap_legacy_base %lu\n"
|
2018-01-05 00:17:59 +00:00
|
|
|
"pgd %px mm_users %d mm_count %d pgtables_bytes %lu map_count %d\n"
|
2014-10-09 22:28:37 +00:00
|
|
|
"hiwater_rss %lx hiwater_vm %lx total_vm %lx locked_vm %lx\n"
|
2019-02-06 17:59:15 +00:00
|
|
|
"pinned_vm %llx data_vm %lx exec_vm %lx stack_vm %lx\n"
|
2014-10-09 22:28:37 +00:00
|
|
|
"start_code %lx end_code %lx start_data %lx end_data %lx\n"
|
|
|
|
|
"start_brk %lx brk %lx start_stack %lx\n"
|
|
|
|
|
"arg_start %lx arg_end %lx env_start %lx env_end %lx\n"
|
2021-09-22 16:24:02 +00:00
|
|
|
"binfmt %px flags %lx\n"
|
2014-10-09 22:28:37 +00:00
|
|
|
#ifdef CONFIG_AIO
|
2018-01-05 00:17:59 +00:00
|
|
|
"ioctx_table %px\n"
|
2014-10-09 22:28:37 +00:00
|
|
|
#endif
|
|
|
|
|
#ifdef CONFIG_MEMCG
|
2018-01-05 00:17:59 +00:00
|
|
|
"owner %px "
|
2014-10-09 22:28:37 +00:00
|
|
|
#endif
|
2018-01-05 00:17:59 +00:00
|
|
|
"exe_file %px\n"
|
2014-10-09 22:28:37 +00:00
|
|
|
#ifdef CONFIG_MMU_NOTIFIER
|
2019-12-18 17:40:35 +00:00
|
|
|
"notifier_subscriptions %px\n"
|
2014-10-09 22:28:37 +00:00
|
|
|
#endif
|
|
|
|
|
#ifdef CONFIG_NUMA_BALANCING
|
|
|
|
|
"numa_next_scan %lu numa_scan_offset %lu numa_scan_seq %d\n"
|
|
|
|
|
#endif
|
|
|
|
|
"tlb_flush_pending %d\n"
|
2016-03-15 21:55:59 +00:00
|
|
|
"def_flags: %#lx(%pGv)\n",
|
2014-10-09 22:28:37 +00:00
|
|
|
|
2022-09-06 19:49:06 +00:00
|
|
|
mm, mm->task_size,
|
|
|
|
|
mm->mmap_base, mm->mmap_legacy_base,
|
2014-10-09 22:28:37 +00:00
|
|
|
mm->pgd, atomic_read(&mm->mm_users),
|
|
|
|
|
atomic_read(&mm->mm_count),
|
2017-11-16 01:35:40 +00:00
|
|
|
mm_pgtables_bytes(mm),
|
2014-10-09 22:28:37 +00:00
|
|
|
mm->map_count,
|
|
|
|
|
mm->hiwater_rss, mm->hiwater_vm, mm->total_vm, mm->locked_vm,
|
2019-03-29 03:43:23 +00:00
|
|
|
(u64)atomic64_read(&mm->pinned_vm),
|
2019-02-06 17:59:15 +00:00
|
|
|
mm->data_vm, mm->exec_vm, mm->stack_vm,
|
2014-10-09 22:28:37 +00:00
|
|
|
mm->start_code, mm->end_code, mm->start_data, mm->end_data,
|
|
|
|
|
mm->start_brk, mm->brk, mm->start_stack,
|
|
|
|
|
mm->arg_start, mm->arg_end, mm->env_start, mm->env_end,
|
2021-09-22 16:24:02 +00:00
|
|
|
mm->binfmt, mm->flags,
|
2014-10-09 22:28:37 +00:00
|
|
|
#ifdef CONFIG_AIO
|
|
|
|
|
mm->ioctx_table,
|
|
|
|
|
#endif
|
|
|
|
|
#ifdef CONFIG_MEMCG
|
|
|
|
|
mm->owner,
|
|
|
|
|
#endif
|
|
|
|
|
mm->exe_file,
|
|
|
|
|
#ifdef CONFIG_MMU_NOTIFIER
|
2019-12-18 17:40:35 +00:00
|
|
|
mm->notifier_subscriptions,
|
2014-10-09 22:28:37 +00:00
|
|
|
#endif
|
|
|
|
|
#ifdef CONFIG_NUMA_BALANCING
|
|
|
|
|
mm->numa_next_scan, mm->numa_scan_offset, mm->numa_scan_seq,
|
|
|
|
|
#endif
|
mm: migrate: prevent racy access to tlb_flush_pending
Patch series "fixes of TLB batching races", v6.
It turns out that Linux TLB batching mechanism suffers from various
races. Races that are caused due to batching during reclamation were
recently handled by Mel and this patch-set deals with others. The more
fundamental issue is that concurrent updates of the page-tables allow
for TLB flushes to be batched on one core, while another core changes
the page-tables. This other core may assume a PTE change does not
require a flush based on the updated PTE value, while it is unaware that
TLB flushes are still pending.
This behavior affects KSM (which may result in memory corruption) and
MADV_FREE and MADV_DONTNEED (which may result in incorrect behavior). A
proof-of-concept can easily produce the wrong behavior of MADV_DONTNEED.
Memory corruption in KSM is harder to produce in practice, but was
observed by hacking the kernel and adding a delay before flushing and
replacing the KSM page.
Finally, there is also one memory barrier missing, which may affect
architectures with weak memory model.
This patch (of 7):
Setting and clearing mm->tlb_flush_pending can be performed by multiple
threads, since mmap_sem may only be acquired for read in
task_numa_work(). If this happens, tlb_flush_pending might be cleared
while one of the threads still changes PTEs and batches TLB flushes.
This can lead to the same race between migration and
change_protection_range() that led to the introduction of
tlb_flush_pending. The result of this race was data corruption, which
means that this patch also addresses a theoretically possible data
corruption.
An actual data corruption was not observed, yet the race was was
confirmed by adding assertion to check tlb_flush_pending is not set by
two threads, adding artificial latency in change_protection_range() and
using sysctl to reduce kernel.numa_balancing_scan_delay_ms.
Link: http://lkml.kernel.org/r/20170802000818.4760-2-namit@vmware.com
Fixes: 20841405940e ("mm: fix TLB flush race between migration, and
change_protection_range")
Signed-off-by: Nadav Amit <namit@vmware.com>
Acked-by: Mel Gorman <mgorman@suse.de>
Acked-by: Rik van Riel <riel@redhat.com>
Acked-by: Minchan Kim <minchan@kernel.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-08-10 22:23:56 +00:00
|
|
|
atomic_read(&mm->tlb_flush_pending),
|
2016-03-15 21:55:59 +00:00
|
|
|
mm->def_flags, &mm->def_flags
|
|
|
|
|
);
|
2014-10-09 22:28:37 +00:00
|
|
|
}
|
2023-01-26 19:37:52 +00:00
|
|
|
EXPORT_SYMBOL(dump_mm);
|
2014-10-09 22:28:37 +00:00
|
|
|
|
2018-10-26 22:07:45 +00:00
|
|
|
static bool page_init_poisoning __read_mostly = true;
|
|
|
|
|
|
|
|
|
|
static int __init setup_vm_debug(char *str)
|
|
|
|
|
{
|
|
|
|
|
bool __page_init_poisoning = true;
|
|
|
|
|
|
|
|
|
|
/*
|
|
|
|
|
* Calling vm_debug with no arguments is equivalent to requesting
|
|
|
|
|
* to enable all debugging options we can control.
|
|
|
|
|
*/
|
|
|
|
|
if (*str++ != '=' || !*str)
|
|
|
|
|
goto out;
|
|
|
|
|
|
|
|
|
|
__page_init_poisoning = false;
|
|
|
|
|
if (*str == '-')
|
|
|
|
|
goto out;
|
|
|
|
|
|
|
|
|
|
while (*str) {
|
|
|
|
|
switch (tolower(*str)) {
|
|
|
|
|
case'p':
|
|
|
|
|
__page_init_poisoning = true;
|
|
|
|
|
break;
|
|
|
|
|
default:
|
|
|
|
|
pr_err("vm_debug option '%c' unknown. skipped\n",
|
|
|
|
|
*str);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
str++;
|
|
|
|
|
}
|
|
|
|
|
out:
|
|
|
|
|
if (page_init_poisoning && !__page_init_poisoning)
|
|
|
|
|
pr_warn("Page struct poisoning disabled by kernel command line option 'vm_debug'\n");
|
|
|
|
|
|
|
|
|
|
page_init_poisoning = __page_init_poisoning;
|
|
|
|
|
|
|
|
|
|
return 1;
|
|
|
|
|
}
|
|
|
|
|
__setup("vm_debug", setup_vm_debug);
|
|
|
|
|
|
|
|
|
|
void page_init_poison(struct page *page, size_t size)
|
|
|
|
|
{
|
|
|
|
|
if (page_init_poisoning)
|
|
|
|
|
memset(page, PAGE_POISON_PATTERN, size);
|
|
|
|
|
}
|
2023-05-18 14:55:26 +00:00
|
|
|
|
|
|
|
|
void vma_iter_dump_tree(const struct vma_iterator *vmi)
|
|
|
|
|
{
|
|
|
|
|
#if defined(CONFIG_DEBUG_VM_MAPLE_TREE)
|
|
|
|
|
mas_dump(&vmi->mas);
|
|
|
|
|
mt_dump(vmi->mas.tree, mt_dump_hex);
|
|
|
|
|
#endif /* CONFIG_DEBUG_VM_MAPLE_TREE */
|
|
|
|
|
}
|
|
|
|
|
|
2014-10-09 22:28:34 +00:00
|
|
|
#endif /* CONFIG_DEBUG_VM */
|