On UP:
kernel/sched.c: In function 'wake_up_new_task':
kernel/sched.c:2631: warning: unused variable 'cpu'
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
[ Note, this commit changes the syscall ABI for > 1024 CPUs systems. ]
Recently, some distro decided to use NR_CPUS=4096 for mysterious reasons.
Unfortunately, glibc sched interface has the following definition:
# define __CPU_SETSIZE 1024
# define __NCPUBITS (8 * sizeof (__cpu_mask))
typedef unsigned long int __cpu_mask;
typedef struct
{
__cpu_mask __bits[__CPU_SETSIZE / __NCPUBITS];
} cpu_set_t;
It mean, if NR_CPUS is bigger than 1024, cpu_set_t makes an
ABI issue ...
More recently, Sharyathi Nagesh reported following test program makes
misterious syscall failure:
-----------------------------------------------------------------------
#define _GNU_SOURCE
#include<stdio.h>
#include<errno.h>
#include<sched.h>
int main()
{
cpu_set_t set;
if (sched_getaffinity(0, sizeof(cpu_set_t), &set) < 0)
printf("\n Call is failing with:%d", errno);
}
-----------------------------------------------------------------------
Because the kernel assumes len argument of sched_getaffinity() is bigger
than NR_CPUS. But now it is not correct.
Now we are faced with the following annoying dilemma, due to
the limitations of the glibc interface built in years ago:
(1) if we change glibc's __CPU_SETSIZE definition, we lost
binary compatibility of _all_ application.
(2) if we don't change it, we also lost binary compatibility of
Sharyathi's use case.
Then, I would propse to change the rule of the len argument of
sched_getaffinity().
Old:
len should be bigger than NR_CPUS
New:
len should be bigger than maximum possible cpu id
This creates the following behavior:
(A) In the real 4096 cpus machine, the above test program still
return -EINVAL.
(B) NR_CPUS=4096 but the machine have less than 1024 cpus (almost
all machines in the world), the above can run successfully.
Fortunatelly, BIG SGI machine is mainly used for HPC use case. It means
they can rebuild their programs.
IOW we hope they are not annoyed by this issue ...
Reported-by: Sharyathi Nagesh <sharyath@in.ibm.com>
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Acked-by: Ulrich Drepper <drepper@redhat.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Jack Steiner <steiner@sgi.com>
Cc: Russ Anderson <rja@sgi.com>
Cc: Mike Travis <travis@sgi.com>
LKML-Reference: <20100312161316.9520.A69D9226@jp.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6: (34 commits)
ACPI: processor: push file static MADT pointer into internal map_madt_entry()
ACPI: processor: refactor internal map_lsapic_id()
ACPI: processor: refactor internal map_x2apic_id()
ACPI: processor: refactor internal map_lapic_id()
ACPI: processor: driver doesn't need to evaluate _PDC
ACPI: processor: remove early _PDC optin quirks
ACPI: processor: add internal processor_physically_present()
ACPI: processor: move acpi_get_cpuid into processor_core.c
ACPI: processor: export acpi_get_cpuid()
ACPI: processor: mv processor_pdc.c processor_core.c
ACPI: processor: mv processor_core.c processor_driver.c
ACPI: plan to delete "acpi=ht" boot option
ACPI: remove "acpi=ht" DMI blacklist
PNPACPI: add bus number support
PNPACPI: add window support
resource: add window support
resource: add bus number support
resource: expand IORESOURCE_TYPE_BITS to make room for bus resource type
acpiphp: Execute ACPI _REG method for hotadded devices
ACPI video: Be more liberal in validating _BQC behaviour
...
There's no real need for a pointer to the MADT to be global. The only
function who uses it is map_madt_entry.
This allows us to remove some more ugly #ifdefs.
Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Un-nest the if statements for readability.
Remove comments that re-state the obvious.
Change the control flow so that we no longer need a temp variable.
Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Untangle the nested if conditions to make this function look
more similar to the other map_*apic_id() functions.
Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Now that the early _PDC evaluation path knows how to correctly
evaluate _PDC on only physically present processors, there's no
need for the processor driver to evaluate it later when it loads.
To cover the hotplug case, push _PDC evaluation down into the
hotplug paths.
Cc: x86@kernel.org
Cc: Tony Luck <tony.luck@intel.com>
Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Now that we check for physically present processors before blindly
evaluating _PDC, we no longer need to maintain a DMI opt-in table
nor a kernel param.
Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Detect if a processor is physically present before evaluating _PDC.
We want this because some BIOS will provide a _PDC even for processors
that are not present. These bogus _PDC methods then attempt to load
non-existent tables, which causes problems.
Avoid those bogus landmines.
Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Enumerating processors (via MADT/_MAT) belongs in the processor core,
which is always built-in, rather than living in the processor driver
which may not be built.
Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Rename static get_cpu_id() to acpi_get_cpuid() and export it.
This change also gives us an opportunity to remove the
#ifndef CONFIG_SMP from processor_driver.c and into a header file
where it properly belongs.
Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
We've renamed the old processor_core.c to processor_driver.c, to
convey the idea that it can be built modular and has driver-like
bits.
Now let's re-create a processor_core.c for the bits needed
statically by the rest of the kernel. The contents of processor_pdc.c
are a good starting spot, so let's just rename that file and
complete our three card monte.
Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
The ACPI processor driver can be built as a module. But it has
pieces of code that should always be built statically into the
kernel.
The plan is for processor_core.c to contain the static bits while
processor_driver.c contains the module-like bits.
Since the bulk of the code in the current processor_core.c is
module-like, first step is to rename the file to processor_driver.c
Next step will re-create processor_core.c and cherry-pick out
the static bits.
Acked-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
SuSE added these entries when deploying ACPI in Linux-2.4.
I pulled them into Linux-2.6 on 2003-08-09.
Over the last 6+ years, several entries have proven to be
unnecessary and deleted, while no new entries have been added.
Matthew suggests that they now have negative value, and I agree.
Based-on-patch-by: Matthew Garrett <mjg59@srcf.ucam.org>
Signed-off-by: Len Brown <len.brown@intel.com>
Add support for bus number resources. This is for bridges with a range of
bus numbers behind them. Previously, PNP ignored bus number resources.
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Add support for resource windows. This is for bridge resources, i.e.,
regions where a bridge forwards transactions from the primary to the
secondary side. This does not add support for *setting* windows via
the /proc interface.
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Add support for resource windows. This is for bridge resources, i.e.,
regions where a bridge forwards transactions from the primary to the
secondary side.
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Add support for bus number resources. This is for bridges with a range of
bus numbers behind them.
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
No functional change; this just makes room for another resource type.
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Per ACPI spec, _ERG method should be executed before device driver
gets control for hotpluged device. Firmware might do some configuration
there. See http://bugzilla.kernel.org/show_bug.cgi?id=10805. In this
machine, _REG method of docked device will configure cardbus bridge.
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Tested-by: Paul Martin <pm@debian.org>
Signed-off-by: Len Brown <len.brown@intel.com>