linux/init/main.c, branch v2.6.35

Merge branch 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

2010-07-02T16:52:58Z

* 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: sched: Cure nr_iowait_cpu() users init: Fix comment init, sched: Fix race between init and kthreadd

init: Fix comment

2010-06-30T08:42:44Z

Apparently "pid-1" confuses people... Requested-by: Randy Dunlap Signed-off-by: Peter Zijlstra Cc: torvalds@linux-foundation.org Cc: randy.dunlap@oracle.com Cc: Ilya Loginov LKML-Reference: <1277887031.1868.82.camel@laptop> Signed-off-by: Ingo Molnar

init, sched: Fix race between init and kthreadd

2010-06-28T16:21:30Z

Ilya reported that on a very slow machine he could reliably reproduce a race between forking init and kthreadd. We first fork init so that it obtains pid-1, however since the scheduler is already fully running at this point it can preempt and run the init thread before we spawn and set kthreadd_task. The init thread can then attempt spawning kthreads without kthreadd being present which results in an OOPS. Reported-by: Ilya Loginov Signed-off-by: Peter Zijlstra Acked-by: Linus Torvalds LKML-Reference: <1277736661.3561.110.camel@laptop> Signed-off-by: Ingo Molnar

ACPI: Do not try to set up acpi processor stuff on cores exceeding maxcpus=

2010-06-09T22:04:12Z

Patch is against latest Linus master branch and is expected to be safe bug fix. You get: ACPI: HARDWARE addr space,NOT supported yet for each ACPI defined CPU which status is active, but exceeds maxcpus= count. As these "not booted" CPUs do not run an idle routine and echo X >/proc/acpi/processor/*/throttling did not work I couldn't find a way to really access not onlined/booted machines. Still this should get fixed and /proc/acpi/processor/X dirs of cores exceeding maxcpus should not show up. I wonder whether this could get cleaned up by truncating possible cpu mask and nr_cpu_ids to setup_max_cpus early some day (and not exporting setup_max_cpus anymore then). But this needs touching of a lot other places... Signed-off-by: Thomas Renninger CC: travis@sgi.com CC: linux-acpi@vger.kernel.org CC: lenb@kernel.org Signed-off-by: Len Brown

mem-hotplug: avoid multiple zones sharing same boot strapping boot_pageset

2010-05-25T15:07:01Z

For each new populated zone of hotadded node, need to update its pagesets with dynamically allocated per_cpu_pageset struct for all possible CPUs: 1) Detach zone->pageset from the shared boot_pageset at end of __build_all_zonelists(). 2) Use mutex to protect zone->pageset when it's still shared in onlined_pages() Otherwises, multiple zones of different nodes would share same boot strapping boot_pageset for same CPU, which will finally cause below kernel panic: ------------[ cut here ]------------ kernel BUG at mm/page_alloc.c:1239! invalid opcode: 0000 [#1] SMP ... Call Trace: [] __alloc_pages_nodemask+0x131/0x7b0 [] alloc_pages_current+0x87/0xd0 [] __page_cache_alloc+0x67/0x70 [] __do_page_cache_readahead+0x120/0x260 [] ra_submit+0x21/0x30 [] ondemand_readahead+0x166/0x2c0 [] page_cache_async_readahead+0x80/0xa0 [] generic_file_aio_read+0x364/0x670 [] nfs_file_read+0xca/0x130 [] do_sync_read+0xfa/0x140 [] vfs_read+0xb5/0x1a0 [] sys_read+0x51/0x80 [] system_call_fastpath+0x16/0x1b RIP [] get_page_from_freelist+0x883/0x900 RSP ---[ end trace 4bda28328b9990db ] [akpm@linux-foundation.org: merge fix] Signed-off-by: Haicheng Li Signed-off-by: Wu Fengguang Reviewed-by: Andi Kleen Reviewed-by: Christoph Lameter Cc: Mel Gorman Cc: Tejun Heo Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

x86, kgdb, init: Add early and late debug states

2010-05-21T02:04:29Z

The kernel debugger can operate well before mm_init(), but the x86 hardware breakpoint code which uses the perf api requires that the kernel allocators are initialized. This means the kernel debug core needs to provide an optional arch specific call back to allow the initialization functions to run after the kernel has been further initialized. The kdb shell already had a similar restriction with an early initialization and late initialization. The kdb_init() was moved into the debug core's version of the late init which is called dbg_late_init(); CC: kgdb-bugreport@lists.sourceforge.net Signed-off-by: Jason Wessel

kdb: core for kgdb back end (2 of 2)

2010-05-21T02:04:21Z

This patch contains the hooks and instrumentation into kernel which live outside the kernel/debug directory, which the kdb core will call to run commands like lsmod, dmesg, bt etc... CC: linux-arch@vger.kernel.org Signed-off-by: Jason Wessel Signed-off-by: Martin Hicks

include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h

2010-03-30T13:02:32Z

percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo Guess-its-ok-by: Christoph Lameter Cc: Ingo Molnar Cc: Lee Schermerhorn

cpuset: fix the problem that cpuset_mem_spread_node() returns an offline node

2010-03-24T23:31:21Z

cpuset_mem_spread_node() returns an offline node, and causes an oops. This patch fixes it by initializing task->mems_allowed to node_states[N_HIGH_MEMORY], and updating task->mems_allowed when doing memory hotplug. Signed-off-by: Miao Xie Acked-by: David Rientjes Reported-by: Nick Piggin Tested-by: Nick Piggin Cc: Paul Menage Cc: Li Zefan Cc: Ingo Molnar Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

init/main.c: make setup_max_cpus static for !SMP

2010-03-06T19:26:32Z

The only in tree external users of the symbol setup_max_cpus are in arch/x86/. The files ./kernel/alternative.c, ./kernel/visws_quirks.c, and ./mm/kmemcheck/kmemcheck.c are all guarded by CONFIG_SMP being defined. For this case the symbol is an unsigned int and declared as an extern in include/linux/smp.h. When CONFIG_SMP is not defined the symbol setup_max_cpus is a constant value that is only used in init/main.c. Make the symbol static for this case. Signed-off-by: H Hartley Sweeten Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds