| Age | Commit message (Collapse) | Author | Files | Lines |
|---|
|
The 1-bit shift rotation to the left on x variable located on
4 last if statement can be removed because the computed value is will
not be used afront.
Signed-off-by: Gustavo Pimentel <[email protected]>
Signed-off-by: Vineet Gupta <[email protected]>
|
|
NPS customers are no longer doing active development, as evident from
rand config build failures reported in recent times, so drop support
for NPS platform.
Tested-by: kernel test robot <[email protected]>
Signed-off-by: Vineet Gupta <[email protected]>
|
|
Based on 2 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 version 2 as
published by the free software foundation
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation #
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 4122 file(s).
Signed-off-by: Thomas Gleixner <[email protected]>
Reviewed-by: Enrico Weigelt <[email protected]>
Reviewed-by: Kate Stewart <[email protected]>
Reviewed-by: Allison Randal <[email protected]>
Cc: [email protected]
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>
|
|
| CC mm/nobootmem.o
|In file included from ./include/asm-generic/bug.h:18:0,
| from ./arch/arc/include/asm/bug.h:32,
| from ./include/linux/bug.h:5,
| from ./include/linux/mmdebug.h:5,
| from ./include/linux/gfp.h:5,
| from ./include/linux/slab.h:15,
| from mm/nobootmem.c:14:
|mm/nobootmem.c: In function '__free_pages_memory':
|./include/linux/kernel.h:845:29: warning: comparison of distinct pointer types lacks a cast
| (!!(sizeof((typeof(x) *)1 == (typeof(y) *)1)))
| ^
|./include/linux/kernel.h:859:4: note: in expansion of macro '__typecheck'
| (__typecheck(x, y) && __no_side_effects(x, y))
| ^~~~~~~~~~~
|./include/linux/kernel.h:869:24: note: in expansion of macro '__safe_cmp'
| __builtin_choose_expr(__safe_cmp(x, y), \
| ^~~~~~~~~~
|./include/linux/kernel.h:878:19: note: in expansion of macro '__careful_cmp'
| #define min(x, y) __careful_cmp(x, y, <)
| ^~~~~~~~~~~~~
|mm/nobootmem.c:104:11: note: in expansion of macro 'min'
| order = min(MAX_ORDER - 1UL, __ffs(start));
Change __ffs return value from 'int' to 'unsigned long' as it
is done in other implementations (like asm-generic, x86, etc...)
to avoid build-time warnings in places where type is strictly
checked.
As __ffs may return values in [0-31] interval changing return
type to unsigned is valid.
Signed-off-by: Eugeniy Paltsev <[email protected]>
Signed-off-by: Vineet Gupta <[email protected]>
|
|
When testing in userspace, UBSAN pointed out that shifting into the sign
bit is undefined behaviour. It doesn't really make sense to ask for the
highest set bit of a negative value, so just turn the argument type into
an unsigned int.
Some architectures (eg ppc) already had it declared as an unsigned int,
so I don't expect too many problems.
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Matthew Wilcox <[email protected]>
Acked-by: Thomas Gleixner <[email protected]>
Acked-by: Geert Uytterhoeven <[email protected]>
Cc: <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
|
|
We need our own implementaions since we lack LLSC support.
Our extended ISA provided with optimized solution for all 32bit
operations we see in these three headers.
Signed-off-by: Noam Camus <[email protected]>
|
|
commit 80f420842ff42 removed the ARC bitops microoptimization but failed
to prune the comments to same effect
Fixes: 80f420842ff42 ("ARC: Make ARC bitops "safer" (add anti-optimization)")
Signed-off-by: Vineet Gupta <[email protected]>
|
|
ARCompact/ARCv2 ISA provide that any instructions which deals with
bitpos/count operand ASL, LSL, BSET, BCLR, BMSK .... will only consider
lower 5 bits. i.e. auto-clamp the pos to 0-31.
ARC Linux bitops exploited this fact by NOT explicitly masking out upper
bits for @nr operand in general, saving a bunch of AND/BMSK instructions
in generated code around bitops.
While this micro-optimization has worked well over years it is NOT safe
as shifting a number with a value, greater than native size is
"undefined" per "C" spec.
So as it turns outm EZChip ran into this eventually, in their massive
muti-core SMP build with 64 cpus. There was a test_bit() inside a loop
from 63 to 0 and gcc was weirdly optimizing away the first iteration
(so it was really adhering to standard by implementing undefined behaviour
vs. removing all the iterations which were phony i.e. (1 << [63..32])
| for i = 63 to 0
| X = ( 1 << i )
| if X == 0
| continue
So fix the code to do the explicit masking at the expense of generating
additional instructions. Fortunately, this can be mitigated to a large
extent as gcc has SHIFT_COUNT_TRUNCATED which allows combiner to fold
masking into shift operation itself. It is currently not enabled in ARC
gcc backend, but could be done after a bit of testing.
Fixes STAR 9000866918 ("unsafe "undefined behavior" code in kernel")
Reported-by: Noam Camus <[email protected]>
Cc: <[email protected]>
Signed-off-by: Vineet Gupta <[email protected]>
|
|
No semantical changes !
Acked-by: Peter Zijlstra (Intel) <[email protected]>
Signed-off-by: Vineet Gupta <[email protected]>
|
|
- arch_spin_lock/unlock were lacking the ACQUIRE/RELEASE barriers
Since ARCv2 only provides load/load, store/store and all/all, we need
the full barrier
- LLOCK/SCOND based atomics, bitops, cmpxchg, which return modified
values were lacking the explicit smp barriers.
- Non LLOCK/SCOND varaints don't need the explicit barriers since that
is implicity provided by the spin locks used to implement the
critical section (the spin lock barriers in turn are also fixed in
this commit as explained above
Cc: Paul E. McKenney <[email protected]>
Cc: [email protected]
Acked-by: Peter Zijlstra (Intel) <[email protected]>
Signed-off-by: Vineet Gupta <[email protected]>
|
|
The notable features are:
- SMP configurations of upto 4 cores with coherency
- Optional L2 Cache and IO-Coherency
- Revised Interrupt Architecture (multiple priorites, reg banks,
auto stack switch, auto regfile save/restore)
- MMUv4 (PIPT dcache, Huge Pages)
- Instructions for
* 64bit load/store: LDD, STD
* Hardware assisted divide/remainder: DIV, REM
* Function prologue/epilogue: ENTER_S, LEAVE_S
* IRQ enable/disable: CLRI, SETI
* pop count: FFS, FLS
* SETcc, BMSKN, XBFU...
Signed-off-by: Vineet Gupta <[email protected]>
|
|
This makes test_bit() more like its siblings *_bit() routines.
Also add some comments about the constant @nr micro-optimization
Signed-off-by: Vineet Gupta <[email protected]>
|
|
Verified by doing make headers_install as none of these files are
exported to userspace
|
|
The arc mb() implementation is a compiler barrier(), therefore it all
doesn't matter one way or the other. Simply remove the existing
definitions and use whatever is generated by the defaults.
Signed-off-by: Peter Zijlstra <[email protected]>
Acked-by: Paul E. McKenney <[email protected]>
Link: http://lkml.kernel.org/n/[email protected]
Cc: Linus Torvalds <[email protected]>
Cc: Vineet Gupta <[email protected]>
Cc: [email protected]
Signed-off-by: Ingo Molnar <[email protected]>
|
|
This covers the UP / SMP (with no hardware assist for atomic r-m-w) as
well as ARC700 LLOCK/SCOND insns based.
Signed-off-by: Vineet Gupta <[email protected]>
|