I realize that we fairly recently raised it to 4.8, but the fact is, 4.9
is a much better minimum version to target.
We have a number of workarounds for actual bugs in pre-4.9 gcc versions
(including things like internal compiler errors on ARM), but we also
have some syntactic workarounds for lacking features.
In particular, raising the minimum to 4.9 means that we can now just
assume _Generic() exists, which is likely the much better replacement
for a lot of very convoluted built-time magic with conditionals on
sizeof and/or __builtin_choose_expr() with same_type() etc.
Using _Generic also means that you will need to have a very recent
version of 'sparse', but thats easy to build yourself, and much less of
a hassle than some old gcc version can be.
The latest (in a long string) of reasons for minimum compiler version
upgrades was commit 5435f73d5c ("efi/x86: Fix build with gcc 4").
Ard points out that RHEL 7 uses gcc-4.8, but the people who stay back on
old RHEL versions persumably also don't build their own kernels anyway.
And maybe they should cross-built or just have a little side affair with
a newer compiler?
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull perf tooling updates from Arnaldo Carvalho de Melo:
"These are additional changes to the perf tools, on top of what Ingo
already submitted.
- Further Intel PT call-trace fixes
- Improve SELinux docs and tool warnings
- Fix race at exit in 'perf record' using eventfd.
- Add missing build tests to the default set of 'make -C tools/perf
build-test'
- Sync msr-index.h getting new AMD MSRs to decode and filter in 'perf
trace'.
- Fix fallback to libaudit in 'perf trace' for arches not using
per-arch *.tbl files.
- Fixes for 'perf ftrace'.
- Fixes and improvements for the 'perf stat' metrics.
- Use dummy event to get PERF_RECORD_{FORK,MMAP,etc} while
synthesizing those metadata events for pre-existing threads.
- Fix leaks detected using clang tooling.
- Improvements to PMU event metric testing.
- Report summary for 'perf stat' interval mode at the end, summing up
all the intervals.
- Improve pipe mode, i.e. this now works as expected, continuously
dumping samples:
# perf record -g -e raw_syscalls:sys_enter | perf --no-pager script
- Fixes for event grouping, detecting incompatible groups such as:
# perf stat -e '{cycles,power/energy-cores/}' -v
WARNING: group events cpu maps do not match, disabling group:
anon group { power/energy-cores/, cycles }
power/energy-cores/: 0
cycles: 0-7
- Fixes for 'perf probe': blacklist address checking, number of
kretprobe instances, etc.
- JIT processing improvements and fixes plus the addition of a 'perf
test' entry for the java demangler.
- Add support for synthesizing first/last level cache, TLB and remove
access events from HW tracing in the auxtrace code, first to use is
ARM SPE.
- Vendor events updates and fixes, including for POWER9 and Intel.
- Allow using ~/.perfconfig for removing the ',' separators in 'perf
stat' output.
- Opt-in support for libpfm4"
* tag 'perf-tools-2020-06-02' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux: (120 commits)
perf tools: Remove some duplicated includes
perf symbols: Fix kernel maps for kcore and eBPF
tools arch x86: Sync the msr-index.h copy with the kernel sources
perf stat: Ensure group is defined on top of the same cpu mask
perf libdw: Fix off-by 1 relative directory includes
perf arm-spe: Support synthetic events
perf auxtrace: Add four itrace options
perf tools: Move arm-spe-pkt-decoder.h/c to the new dir
perf test: Initialize memory in dwarf-unwind
perf tests: Don't tail call optimize in unwind test
tools compiler.h: Add attribute to disable tail calls
perf build: Add a LIBPFM4=1 build test entry
perf tools: Add optional support for libpfm4
perf tools: Correct license on jsmn JSON parser
perf jit: Fix inaccurate DWARF line table
perf jvmti: Remove redundant jitdump line table entries
perf build: Add NO_SDT=1 to the default set of build tests
perf build: Add NO_LIBCRYPTO=1 to the default set of build tests
perf build: Add NO_SYSCALL_TABLE=1 to the build tests
perf build: Remove libaudit from the default feature checks
...
Pull documentation updates from Jonathan Corbet:
"A fair amount of stuff this time around, dominated by yet another
massive set from Mauro toward the completion of the RST conversion. I
*really* hope we are getting close to the end of this. Meanwhile,
those patches reach pretty far afield to update document references
around the tree; there should be no actual code changes there. There
will be, alas, more of the usual trivial merge conflicts.
Beyond that we have more translations, improvements to the sphinx
scripting, a number of additions to the sysctl documentation, and lots
of fixes"
* tag 'docs-5.8' of git://git.lwn.net/linux: (130 commits)
Documentation: fixes to the maintainer-entry-profile template
zswap: docs/vm: Fix typo accept_threshold_percent in zswap.rst
tracing: Fix events.rst section numbering
docs: acpi: fix old http link and improve document format
docs: filesystems: add info about efivars content
Documentation: LSM: Correct the basic LSM description
mailmap: change email for Ricardo Ribalda
docs: sysctl/kernel: document unaligned controls
Documentation: admin-guide: update bug-hunting.rst
docs: sysctl/kernel: document ngroups_max
nvdimm: fixes to maintainter-entry-profile
Documentation/features: Correct RISC-V kprobes support entry
Documentation/features: Refresh the arch support status files
Revert "docs: sysctl/kernel: document ngroups_max"
docs: move locking-specific documents to locking/
docs: move digsig docs to the security book
docs: move the kref doc into the core-api book
docs: add IRQ documentation at the core-api book
docs: debugging-via-ohci1394.txt: add it to the core-api book
docs: fix references for ipmi.rst file
...
To pick up the changes in these csets:
295bcca849 ("linux/bits.h: add compile time sanity check of GENMASK inputs")
3945ff37d2 ("linux/bits.h: Extract common header for vDSO")
To address this tools/perf build warning:
Warning: Kernel ABI header at 'tools/include/linux/bits.h' differs from latest version at 'include/linux/bits.h'
diff -u tools/include/linux/bits.h include/linux/bits.h
This clashes with usage of userspace's static_assert(), that, at least
on glibc, is guarded by a ifnded/endif pair, do the same to our copy of
build_bug.h and avoid that diff in check_headers.sh so that we continue
checking for drifts with the kernel sources master copy.
This will all be tested with the set of build containers that includes
uCLibc, musl libc, lots of glibc versions in lots of distros and cross
build environments.
The tools/objtool, tools/bpf, etc were tested as well.
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Rikard Falkeborn <rikard.falkeborn@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
To get in line with:
8165b57bca ("linux/const.h: Extract common header for vDSO")
And silence this tools/perf/ build warning:
Warning: Kernel ABI header at 'tools/include/linux/const.h' differs from latest version at 'include/linux/const.h'
diff -u tools/include/linux/const.h include/linux/const.h
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Continue what commit:
d820ac4c2f ("locking: rename trace_softirq_[enter|exit] => lockdep_softirq_[enter|exit]")
started, rename these to avoid confusing them with tracepoints.
git grep -l "trace_\(soft\|hard\)\(irq_context\|irqs_enabled\)" | while read file;
do
sed -ie 's/trace_\(soft\|hard\)\(irq_context\|irqs_enabled\)/lockdep_\1\2/g' $file;
done
Reported-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Will Deacon <will@kernel.org>
Link: https://lkml.kernel.org/r/20200320115859.178626842@infradead.org
Disable a couple of compilation warnings (which are treated as errors)
on strlcpy() definition and declaration, allowing users to compile perf
and kernel (objtool) when:
1. glibc have strlcpy() (such as in ALT Linux since 2004) objtool and
perf build fails with this (in gcc):
In file included from exec-cmd.c:3:
tools/include/linux/string.h:20:15: error: redundant redeclaration of ‘strlcpy’ [-Werror=redundant-decls]
20 | extern size_t strlcpy(char *dest, const char *src, size_t size);
2. clang ignores `-Wredundant-decls', but produces another warning when
building perf:
CC util/string.o
../lib/string.c:99:8: error: attribute declaration must precede definition [-Werror,-Wignored-attributes]
size_t __weak strlcpy(char *dest, const char *src, size_t size)
../../tools/include/linux/compiler.h:66:34: note: expanded from macro '__weak'
# define __weak __attribute__((weak))
/usr/include/bits/string_fortified.h:151:8: note: previous definition is here
__NTH (strlcpy (char *__restrict __dest, const char *__restrict __src,
Committer notes:
The
#pragma GCC diagnostic
directive was introduced in gcc 4.6, so check for that as well.
Fixes: ce99091 ("perf tools: Move strlcpy() from perf to tools/lib/string.c")
Fixes: 0215d59 ("tools lib: Reinstate strlcpy() header guard with __UCLIBC__")
Resolves: https://bugzilla.kernel.org/show_bug.cgi?id=118481
Signed-off-by: Vitaly Chikunov <vt@altlinux.org>
Reviewed-by: Dmitry Levin <ldv@altlinux.org>
Cc: Dmitry Levin <ldv@altlinux.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: kbuild test robot <lkp@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: stable@vger.kernel.org
Cc: Vineet Gupta <vineet.gupta1@synopsys.com>
Link: http://lore.kernel.org/lkml/20191224172029.19690-1-vt@altlinux.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Change the definition of the RBCOMPUTE function. The propagate callback
repeatedly calls RBCOMPUTE as it moves from leaf to root. it wants to
stop recomputing once the augmented subtree information doesn't change.
This was previously checked using the == operator, but that only works
when the augmented subtree information is a scalar field. This commit
modifies the RBCOMPUTE function so that it now sets the augmented subtree
information instead of returning it, and returns a boolean value
indicating if the propagate callback should stop.
The motivation for this change is that I want to introduce augmented
rbtree uses where the augmented data for the subtree is a struct instead
of a scalar.
Link: http://lkml.kernel.org/r/20190703040156.56953-4-walken@google.com
Signed-off-by: Michel Lespinasse <walken@google.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: Uladzislau Rezki <urezki@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Patch series "make RB_DECLARE_CALLBACKS more generic", v3.
These changes are intended to make the RB_DECLARE_CALLBACKS macro more
generic (allowing the aubmented subtree information to be a struct instead
of a scalar).
I have verified the compiled lib/interval_tree.o and mm/mmap.o files to
check that they didn't change. This held as expected for interval_tree.o;
mmap.o did have some changes which could be reverted by marking
__vma_link_rb as noinline. I did not add such a change to the patchset; I
felt it was reasonable enough to leave the inlining decision up to the
compiler.
This patch (of 3):
Add a short comment summarizing the arguments to RB_DECLARE_CALLBACKS.
The arguments are also now capitalized. This copies the style of the
INTERVAL_TREE_DEFINE macro.
No functional changes in this commit, only comments and capitalization.
Link: http://lkml.kernel.org/r/20190703040156.56953-2-walken@google.com
Signed-off-by: Michel Lespinasse <walken@google.com>
Acked-by: Davidlohr Bueso <dbueso@suse.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Uladzislau Rezki <urezki@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull networking updates from David Miller:
1) Support IPV6 RA Captive Portal Identifier, from Maciej Żenczykowski.
2) Use bio_vec in the networking instead of custom skb_frag_t, from
Matthew Wilcox.
3) Make use of xmit_more in r8169 driver, from Heiner Kallweit.
4) Add devmap_hash to xdp, from Toke Høiland-Jørgensen.
5) Support all variants of 5750X bnxt_en chips, from Michael Chan.
6) More RTNL avoidance work in the core and mlx5 driver, from Vlad
Buslov.
7) Add TCP syn cookies bpf helper, from Petar Penkov.
8) Add 'nettest' to selftests and use it, from David Ahern.
9) Add extack support to drop_monitor, add packet alert mode and
support for HW drops, from Ido Schimmel.
10) Add VLAN offload to stmmac, from Jose Abreu.
11) Lots of devm_platform_ioremap_resource() conversions, from
YueHaibing.
12) Add IONIC driver, from Shannon Nelson.
13) Several kTLS cleanups, from Jakub Kicinski.
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1930 commits)
mlxsw: spectrum_buffers: Add the ability to query the CPU port's shared buffer
mlxsw: spectrum: Register CPU port with devlink
mlxsw: spectrum_buffers: Prevent changing CPU port's configuration
net: ena: fix incorrect update of intr_delay_resolution
net: ena: fix retrieval of nonadaptive interrupt moderation intervals
net: ena: fix update of interrupt moderation register
net: ena: remove all old adaptive rx interrupt moderation code from ena_com
net: ena: remove ena_restore_ethtool_params() and relevant fields
net: ena: remove old adaptive interrupt moderation code from ena_netdev
net: ena: remove code duplication in ena_com_update_nonadaptive_moderation_interval _*()
net: ena: enable the interrupt_moderation in driver_supported_features
net: ena: reimplement set/get_coalesce()
net: ena: switch to dim algorithm for rx adaptive interrupt moderation
net: ena: add intr_moder_rx_interval to struct ena_com_dev and use it
net: phy: adin: implement Energy Detect Powerdown mode via phy-tunable
ethtool: implement Energy Detect Powerdown support via phy-tunable
xen-netfront: do not assume sk_buff_head list is empty in error handling
s390/ctcm: Delete unnecessary checks before the macro call “dev_kfree_skb”
net: ena: don't wake up tx queue when down
drop_monitor: Better sanitize notified packets
...
