From: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
After removal of fixup_cpu_present_map() function Alpha ended up with an empty
cpu_present_map, so secondary CPUs on SMP systems are not being started.
Worse, on some platforms we route interrupts to secondary CPUs using
cpu_possible_map which is still populated properly. As a result, these
interrupts go nowhere so the machines like DP264 aren't able to boot even with
a primary CPU.
Fixed basically by s/cpu_present_mask/cpu_present_map/.
Thanks to Ernst Herzberg for reporting the bug and testing the fix.
Cc: Ernst Herzberg <list-lkml@net4u.de>
Cc: Richard Henderson <rth@twiddle.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
I've encountered two problems with 2.6.16 and newer kernels on my API CS20
(dual 833MHz Alpha 21264b processors). The first is the kernel OOPSing
because of a NULL pointer dereference while trying to populate SysFS with the
CPU information. The other is that only one processor was being brought up.
I've included a small Alpha-specific patch that fixes both problems.
The first problem was caused by the CPUs never being properly registered using
register_cpu(), the way it's done on other architectures.
The second problem has to do with the removal of hwrpb_cpu_present_mask in
arch/alpha/kernel/smp.c. In setup_smp() in the 2.6.15 kernel sources,
hwrpb_cpu_present_mask has a bit set for each processor that is probed, and
afterwards cpu_present_mask is set to the cpumask for the boot CPU. In the
same function of the same file in the 2.6.16 sources, instead of
hwrpb_cpu_present_mask being set, cpu_possible_map is updated for each probed
CPU. cpu_present_mask is still set to the cpumask of the boot CPU afterwards.
The problem lies in include/asm-alpha/smp.h, where cpu_possible_map is
#define'd to be cpu_present_mask.
Cleanups from: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
- cpu_present_mask and cpu_possible_map are essentially the same thing
on alpha, as it doesn't support CPU hotplug;
- allocate "struct cpu" only for present CPUs, like sparc64 does.
Static array of "struct cpu" is just a waste of memory.
Signed-off-by: Brian Uhrain <buhrain@rosettastone.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
All the percpu data structure walkers want cpu_possible_map to be
initialized early, but alpha instead populated "hwrpb_cpu_present_mask"
early in setup_smp(), and then initialized cpu_possible_map only much
later.
Thanks go to Heiko Carstens and Dipankar Sarma for noticing.
This fixes it and we can get rid of hwrpb_cpu_present_mask entirely.
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
use task_thread_info() for accesses to thread_info of task in arch/alpha
and include/asm-alpha
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch (written by me and also containing many suggestions of Arjan van
de Ven) does a major cleanup of the spinlock code. It does the following
things:
- consolidates and enhances the spinlock/rwlock debugging code
- simplifies the asm/spinlock.h files
- encapsulates the raw spinlock type and moves generic spinlock
features (such as ->break_lock) into the generic code.
- cleans up the spinlock code hierarchy to get rid of the spaghetti.
Most notably there's now only a single variant of the debugging code,
located in lib/spinlock_debug.c. (previously we had one SMP debugging
variant per architecture, plus a separate generic one for UP builds)
Also, i've enhanced the rwlock debugging facility, it will now track
write-owners. There is new spinlock-owner/CPU-tracking on SMP builds too.
All locks have lockup detection now, which will work for both soft and hard
spin/rwlock lockups.
The arch-level include files now only contain the minimally necessary
subset of the spinlock code - all the rest that can be generalized now
lives in the generic headers:
include/asm-i386/spinlock_types.h | 16
include/asm-x86_64/spinlock_types.h | 16
I have also split up the various spinlock variants into separate files,
making it easier to see which does what. The new layout is:
SMP | UP
----------------------------|-----------------------------------
asm/spinlock_types_smp.h | linux/spinlock_types_up.h
linux/spinlock_types.h | linux/spinlock_types.h
asm/spinlock_smp.h | linux/spinlock_up.h
linux/spinlock_api_smp.h | linux/spinlock_api_up.h
linux/spinlock.h | linux/spinlock.h
/*
* here's the role of the various spinlock/rwlock related include files:
*
* on SMP builds:
*
* asm/spinlock_types.h: contains the raw_spinlock_t/raw_rwlock_t and the
* initializers
*
* linux/spinlock_types.h:
* defines the generic type and initializers
*
* asm/spinlock.h: contains the __raw_spin_*()/etc. lowlevel
* implementations, mostly inline assembly code
*
* (also included on UP-debug builds:)
*
* linux/spinlock_api_smp.h:
* contains the prototypes for the _spin_*() APIs.
*
* linux/spinlock.h: builds the final spin_*() APIs.
*
* on UP builds:
*
* linux/spinlock_type_up.h:
* contains the generic, simplified UP spinlock type.
* (which is an empty structure on non-debug builds)
*
* linux/spinlock_types.h:
* defines the generic type and initializers
*
* linux/spinlock_up.h:
* contains the __raw_spin_*()/etc. version of UP
* builds. (which are NOPs on non-debug, non-preempt
* builds)
*
* (included on UP-non-debug builds:)
*
* linux/spinlock_api_up.h:
* builds the _spin_*() APIs.
*
* linux/spinlock.h: builds the final spin_*() APIs.
*/
All SMP and UP architectures are converted by this patch.
arm, i386, ia64, ppc, ppc64, s390/s390x, x64 was build-tested via
crosscompilers. m32r, mips, sh, sparc, have not been tested yet, but should
be mostly fine.
From: Grant Grundler <grundler@parisc-linux.org>
Booted and lightly tested on a500-44 (64-bit, SMP kernel, dual CPU).
Builds 32-bit SMP kernel (not booted or tested). I did not try to build
non-SMP kernels. That should be trivial to fix up later if necessary.
I converted bit ops atomic_hash lock to raw_spinlock_t. Doing so avoids
some ugly nesting of linux/*.h and asm/*.h files. Those particular locks
are well tested and contained entirely inside arch specific code. I do NOT
expect any new issues to arise with them.
If someone does ever need to use debug/metrics with them, then they will
need to unravel this hairball between spinlocks, atomic ops, and bit ops
that exist only because parisc has exactly one atomic instruction: LDCW
(load and clear word).
From: "Luck, Tony" <tony.luck@intel.com>
ia64 fix
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjanv@infradead.org>
Signed-off-by: Grant Grundler <grundler@parisc-linux.org>
Cc: Matthew Wilcox <willy@debian.org>
Signed-off-by: Hirokazu Takata <takata@linux-m32r.org>
Signed-off-by: Mikael Pettersson <mikpe@csd.uu.se>
Signed-off-by: Benoit Boissinot <benoit.boissinot@ens-lyon.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
"=m" (lock->lock) / "1" (lock->lock) makes gcc4 unhappy; fixed by s/1/m/,
same as in case of i386 rwsem.h where such variant had been accepted
by both Linus and rth.
Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.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!
