This is the first patch in a series of 4, with which the page cache flushing of
parisc will gets fixed and enhanced. This even fixes the nasty "minifail" bug
(http://wiki.parisc-linux.org/TestCases?highlight=%28minifail%29) which
prevented parisc to stay an official debian port. Basically the flush in
copy_user_page together with the TLB patch from commit
7139bc1579 is what fixes the minifail bug.
This patch still uses the TMPALIAS approach. The new copy_user_page
implementation calls flush_dcache_page_asm to flush the user dcache page
(crucial for minifail fix) via a kernel TMPALIAS mapping. After that, it just
copies the page using the kernel mapping. It does a final flush if needed.
Generally it is hard to avoid doing some cache flushes using the kernel mapping
(e.g., copy_to_user_page and copy_from_user_page).
This patch depends on a subsequent change to pacache.S implementing
clear_page_asm and copy_page_asm. These are optimized routines to clear and
copy a page. The calls in clear_user_page and copy_user_page could be replaced
by calls to memset and memcpy, respectively. I tested prefetch optimizations
in clear_page_asm and copy_page_asm but didn't see any significant performance
improvement on rp3440. I'm not sure if these are routines are significantly
faster than memset and/or memcpy, but they are there for further performance
evaluation.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
This allows us to move duplicated code in <asm/atomic.h>
(atomic_inc_not_zero() for now) to <linux/atomic.h>
Signed-off-by: Arun Sharma <asharma@fb.com>
Reviewed-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: David Miller <davem@davemloft.net>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch adds the ftrace debugging functionality to the parisc kernel.
It will currently only work with 64bit kernels, because the gcc options -pg
and -ffunction-sections can't be enabled at the same time and -ffunction-sections
is still needed to be able to link 32bit kernels.
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
Semaphores are no longer performance-critical, so a generic C
implementation is better for maintainability, debuggability and
extensibility. Thanks to Peter Zijlstra for fixing the lockdep
warning. Thanks to Harvey Harrison for pointing out that the
unlikely() was unnecessary.
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
This reverts commit efb80e7e09, it turned
out to cause sporadic problems with the timer interrupt on 32-bit kernels.
Needs more investigation.
Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
Currently we're hacking libs-y to include libgcc.a, but this has
unforeseen consequences since the userspace libgcc is linked with fpregs
enabled. We need the kernel to stop using fpregs in an uncontrolled manner
to implement lazy fpu state saves.
Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
While cleaning up parisc_ksyms.c earlier, I noticed that strpbrk wasn't
being exported from lib/string.c. Investigating further, I noticed a
changeset that removed its export and added it to _ksyms.c on a few more
architectures. The justification was that "other arches do it."
I think this is wrong, since no architecture currently defines
__HAVE_ARCH_STRPBRK, there's no reason for any of them to be exporting it
themselves. Therefore, consolidate the export to lib/string.c.
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Some symbols are exported both in parisc_ksyms.c, and at their
definition site. Nuke the redundant EXPORT_SYMBOL in ksyms to quiet
warnings when vmlinux is linked.
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
Move the EXPORT_SYMBOL() of pm_power_off from parisc_ksyms.c to the
location of its definition in process.c
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
John David Anglin