Percpu allocator honors alignment request upto PAGE_SIZE and both the
percpu addresses in the percpu address space and the translated kernel
addresses should be aligned accordingly. The calculation of the
former depends on the alignment of percpu output section in the kernel
image.
The linker script macros PERCPU_VADDR() and PERCPU() are used to
define this output section and the latter takes @align parameter.
Several architectures are using @align smaller than PAGE_SIZE breaking
percpu memory alignment.
This patch removes @align parameter from PERCPU(), renames it to
PERCPU_SECTION() and makes it always align to PAGE_SIZE. While at it,
add PCPU_SETUP_BUG_ON() checks such that alignment problems are
reliably detected and remove percpu alignment comment recently added
in workqueue.c as the condition would trigger BUG way before reaching
there.
For um, this patch raises the alignment of percpu area. As the area
is in .init, there shouldn't be any noticeable difference.
This problem was discovered by David Howells while debugging boot
failure on mn10300.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Cc: uclinux-dist-devel@blackfin.uclinux.org
Cc: David Howells <dhowells@redhat.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: user-mode-linux-devel@lists.sourceforge.net
* git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile: (27 commits)
arch/tile: support newer binutils assembler shift semantics
arch/tile: fix deadlock bugs in rwlock implementation
drivers/edac: provide support for tile architecture
tile on-chip network driver: sync up with latest fixes
arch/tile: support 4KB page size as well as 64KB
arch/tile: add some more VMSPLIT options and use consistent naming
arch/tile: fix some comments and whitespace
arch/tile: export some additional module symbols
arch/tile: enhance existing finv_buffer_remote() routine
arch/tile: fix two bugs in the backtracer code
arch/tile: use extended assembly to inline __mb_incoherent()
arch/tile: use a cleaner technique to enable interrupt for cpu_idle()
arch/tile: sync up with <arch/sim.h> and <arch/sim_def.h> changes
arch/tile: fix reversed test of strict_strtol() return value
arch/tile: avoid a simulator warning during bootup
arch/tile: export <asm/hardwall.h> to userspace
arch/tile: warn and retry if an IPI is not accepted by the target cpu
arch/tile: stop disabling INTCTRL_1 interrupts during hypervisor downcalls
arch/tile: fix __ndelay etc to work better
arch/tile: bug fix: exec'ed task thought it was still single-stepping
...
Fix up trivial conflict in arch/tile/kernel/vmlinux.lds.S (percpu
alignment vs section naming convention fix)
The convention changed to, e.g., ".data..page_aligned". This commit
fixes the places in the tile architecture that were still using the
old convention. One tile-specific section (.init.page) was dropped
in favor of just using an "aligned" attribute.
Sam Ravnborg <sam@ravnborg.org> pointed out __PAGE_ALIGNED_BSS, etc.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Currently percpu readmostly subsection may share cachelines with other
percpu subsections which may result in unnecessary cacheline bounce
and performance degradation.
This patch adds @cacheline parameter to PERCPU() and PERCPU_VADDR()
linker macros, makes each arch linker scripts specify its cacheline
size and use it to align percpu subsections.
This is based on Shaohua's x86 only patch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Shaohua Li <shaohua.li@intel.com>
This commit is primarily changes caused by reviewing "sparse"
and "checkpatch" output on our sources, so is somewhat noisy, since
things like "printk() -> pr_err()" (or whatever) throughout the
codebase tend to get tedious to read. Rather than trying to tease
apart precisely which things changed due to which type of code
review, this commit includes various cleanups in the code:
- sparse: Add declarations in headers for globals.
- sparse: Fix __user annotations.
- sparse: Using gfp_t consistently instead of int.
- sparse: removing functions not actually used.
- checkpatch: Clean up printk() warnings by using pr_info(), etc.;
also avoid partial-line printks except in bootup code.
- checkpatch: Use exposed structs rather than typedefs.
- checkpatch: Change some C99 comments to C89 comments.
In addition, a couple of minor other changes are rolled in
to this commit:
- Add support for a "raise" instruction to cause SIGFPE, etc., to be raised.
- Remove some compat code that is unnecessary when we fully eliminate
some of the deprecated syscalls from the generic syscall ABI.
- Update the tile_defconfig to reflect current config contents.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
This change is the core kernel support for TILEPro and TILE64 chips.
No driver support (except the console driver) is included yet.
This includes the relevant Linux headers in asm/; the low-level
low-level "Tile architecture" headers in arch/, which are
shared with the hypervisor, etc., and are build-system agnostic;
and the relevant hypervisor headers in hv/.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Reviewed-by: Paul Mundt <lethal@linux-sh.org>
Tejun Heo