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* revert "cpumask: don't perform while loop in cpumask_next_and()"Andrew Morton2015-06-181-5/+4
| | | | | | | | | | | | | | | | | Revert commit 534b483a86e6 ("cpumask: don't perform while loop in cpumask_next_and()"). This was a minor optimization, but it puts a `struct cpumask' on the stack, which consumes too much stack space. Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reported-by: Peter Zijlstra <peterz@infradead.org> Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: Tejun Heo <tj@kernel.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Amir Vadai <amirv@mellanox.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* cpumask_set_cpu_local_first => cpumask_local_spread, lamentRusty Russell2015-05-281-48/+26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | da91309e0a7e (cpumask: Utility function to set n'th cpu...) created a genuinely weird function. I never saw it before, it went through DaveM. (He only does this to make us other maintainers feel better about our own mistakes.) cpumask_set_cpu_local_first's purpose is say "I need to spread things across N online cpus, choose the ones on this numa node first"; you call it in a loop. It can fail. One of the two callers ignores this, the other aborts and fails the device open. It can fail in two ways: allocating the off-stack cpumask, or through a convoluted codepath which AFAICT can only occur if cpu_online_mask changes. Which shouldn't happen, because if cpu_online_mask can change while you call this, it could return a now-offline cpu anyway. It contains a nonsensical test "!cpumask_of_node(numa_node)". This was drawn to my attention by Geert, who said this causes a warning on Sparc. It sets a single bit in a cpumask instead of returning a cpu number, because that's what the callers want. It could be made more efficient by passing the previous cpu rather than an index, but that would be more invasive to the callers. Fixes: da91309e0a7e8966d916a74cce42ed170fde06bf Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (then rebased) Tested-by: Amir Vadai <amirv@mellanox.com> Acked-by: Amir Vadai <amirv@mellanox.com> Acked-by: David S. Miller <davem@davemloft.net>
* Merge tag 'cpumask-next-for-linus' of ↵Linus Torvalds2015-04-201-28/+0
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux Pull final removal of deprecated cpus_* cpumask functions from Rusty Russell: "This is the final removal (after several years!) of the obsolete cpus_* functions, prompted by their mis-use in staging. With these function removed, all cpu functions should only iterate to nr_cpu_ids, so we finally only allocate that many bits when cpumasks are allocated offstack" * tag 'cpumask-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: (25 commits) cpumask: remove __first_cpu / __next_cpu cpumask: resurrect CPU_MASK_CPU0 linux/cpumask.h: add typechecking to cpumask_test_cpu cpumask: only allocate nr_cpumask_bits. Fix weird uses of num_online_cpus(). cpumask: remove deprecated functions. mips: fix obsolete cpumask_of_cpu usage. x86: fix more deprecated cpu function usage. ia64: remove deprecated cpus_ usage. powerpc: fix deprecated CPU_MASK_CPU0 usage. CPU_MASK_ALL/CPU_MASK_NONE: remove from deprecated region. staging/lustre/o2iblnd: Don't use cpus_weight staging/lustre/libcfs: replace deprecated cpus_ calls with cpumask_ staging/lustre/ptlrpc: Do not use deprecated cpus_* functions blackfin: fix up obsolete cpu function usage. parisc: fix up obsolete cpu function usage. tile: fix up obsolete cpu function usage. arm64: fix up obsolete cpu function usage. mips: fix up obsolete cpu function usage. x86: fix up obsolete cpu function usage. ...
| * cpumask: remove __first_cpu / __next_cpuRusty Russell2015-04-191-21/+0
| | | | | | | | | | | | | | | | | | | | | | They were for use by the deprecated first_cpu() and next_cpu() wrappers, but sparc used them directly. They're now replaced by cpumask_first / cpumask_next. And __next_cpu_nr is completely obsolete. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Acked-by: David S. Miller <davem@davemloft.net>
| * cpumask: only allocate nr_cpumask_bits.Rusty Russell2015-03-101-7/+0
| | | | | | | | | | | | | | Now we'll find out the hard way if anyone has CPUMASK_OFFSTACK and is returning these or assigning them. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* | cpumask: don't perform while loop in cpumask_next_and()Sergey Senozhatsky2015-04-171-4/+5
|/ | | | | | | | | | | | | | | | | | | cpumask_next_and() is looking for cpumask_next() in src1 in a loop and tests if found cpu is also present in src2. remove that loop, perform cpumask_and() of src1 and src2 first and use that new mask to find cpumask_next(). Apart from removing while loop, ./bloat-o-meter on x86_64 shows add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-8 (-8) function old new delta cpumask_next_and 62 54 -8 Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: Tejun Heo <tj@kernel.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Amir Vadai <amirv@mellanox.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* lib/cpumask: cpumask_set_cpu_local_first to use all cores when numa node is ↵Amir Vadai2014-07-021-1/+1
| | | | | | | | | not defined When device is non numa aware (numa_node == -1), use all online cpu's. Signed-off-by: Amir Vadai <amirv@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* cpumask: Utility function to set n'th cpu - local cpu firstAmir Vadai2014-06-111-0/+63
| | | | | | | | | | | | | | | | | | | | | This function sets the n'th cpu - local cpu's first. For example: in a 16 cores server with even cpu's local, will get the following values: cpumask_set_cpu_local_first(0, numa, cpumask) => cpu 0 is set cpumask_set_cpu_local_first(1, numa, cpumask) => cpu 2 is set ... cpumask_set_cpu_local_first(7, numa, cpumask) => cpu 14 is set cpumask_set_cpu_local_first(8, numa, cpumask) => cpu 1 is set cpumask_set_cpu_local_first(9, numa, cpumask) => cpu 3 is set ... cpumask_set_cpu_local_first(15, numa, cpumask) => cpu 15 is set Curently this function will be used by multi queue networking devices to calculate the irq affinity mask, such that as many local cpu's as possible will be utilized to handle the mq device irq's. Signed-off-by: Amir Vadai <amirv@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: Revert mlx4 cpumask changes.David S. Miller2014-06-011-64/+0
| | | | | | | | | | | This reverts commit 70a640d0dae3a9b1b222ce673eb5d92c263ddd61 ("net/mlx4_en: Use affinity hint") and commit c8865b64b05b2f4eeefd369373e9c8aeb069e7a1 ("cpumask: Utility function to set n'th cpu - local cpu first") because these changes break the build when SMP is disabled amongst other things. Reported-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* cpumask: Utility function to set n'th cpu - local cpu firstAmir Vadai2014-06-011-0/+64
| | | | | | | | | | | | | | | | | | | | | This function sets the n'th cpu - local cpu's first. For example: in a 16 cores server with even cpu's local, will get the following values: cpumask_set_cpu_local_first(0, numa, cpumask) => cpu 0 is set cpumask_set_cpu_local_first(1, numa, cpumask) => cpu 2 is set ... cpumask_set_cpu_local_first(7, numa, cpumask) => cpu 14 is set cpumask_set_cpu_local_first(8, numa, cpumask) => cpu 1 is set cpumask_set_cpu_local_first(9, numa, cpumask) => cpu 3 is set ... cpumask_set_cpu_local_first(15, numa, cpumask) => cpu 15 is set Curently this function will be used by multi queue networking devices to calculate the irq affinity mask, such that as many local cpu's as possible will be utilized to handle the mq device irq's. Signed-off-by: Amir Vadai <amirv@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* lib/cpumask.c: use memblock apis for early memory allocationsSantosh Shilimkar2014-01-211-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Switch to memblock interfaces for early memory allocator instead of bootmem allocator. No functional change in beahvior than what it is in current code from bootmem users points of view. Archs already converted to NO_BOOTMEM now directly use memblock interfaces instead of bootmem wrappers build on top of memblock. And the archs which still uses bootmem, these new apis just fallback to exiting bootmem APIs. Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Christoph Lameter <cl@linux-foundation.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Grygorii Strashko <grygorii.strashko@ti.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Michal Hocko <mhocko@suse.cz> Cc: Paul Walmsley <paul@pwsan.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: Russell King <linux@arm.linux.org.uk> Cc: Tejun Heo <tj@kernel.org> Cc: Tony Lindgren <tony@atomide.com> Cc: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* bootmem: fix wrong call parameter for free_bootmem()Joonsoo Kim2012-12-111-1/+1
| | | | | | | | | | | | | | | | | | | It is strange that alloc_bootmem() returns a virtual address and free_bootmem() requires a physical address. Anyway, free_bootmem()'s first parameter should be physical address. There are some call sites for free_bootmem() with virtual address. So fix them. [akpm@linux-foundation.org: improve free_bootmem() and free_bootmem_pate() documentation] Signed-off-by: Joonsoo Kim <js1304@gmail.com> Cc: Haavard Skinnemoen <hskinnemoen@gmail.com> Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* lib/cpumask.c: remove __any_online_cpu()Srivatsa S. Bhat2012-03-281-12/+0
| | | | | | | | | | | | | __any_online_cpu() is not optimal and also unnecessary. So, replace its use by faster cpumask_* operations. Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Venkatesh Pallipadi <venki@google.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* lib: reduce the use of module.h wherever possiblePaul Gortmaker2012-03-071-1/+1
| | | | | | | | | | For files only using THIS_MODULE and/or EXPORT_SYMBOL, map them onto including export.h -- or if the file isn't even using those, then just delete the include. Fix up any implicit include dependencies that were being masked by module.h along the way. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
* cpumask: alloc_cpumask_var() use NUMA_NO_NODEKOSAKI Motohiro2011-07-261-1/+1
| | | | | | | | | | NUMA_NO_NODE and numa_node_id() have different meanings. NUMA_NO_NODE is obviously the recommended fallback. Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Christoph Lameter <cl@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* cpumask: convert for_each_cpumask() with for_each_cpu()KOSAKI Motohiro2011-07-261-1/+1
| | | | | | | | Adapt new API fashion. Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo2010-03-301-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | implicit slab.h inclusion from percpu.h 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 <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
* x86: remove some alloc_bootmem_cpumask_var callingYinghai Lu2009-06-111-9/+2
| | | | | | | | | | | Now that we set up the slab allocator earlier, we can get rid of some alloc_bootmem_cpumask_var() calls in boot code. Cc: Ingo Molnar <mingo@elte.hu> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
* cpumask: introduce zalloc_cpumask_varYinghai Lu2009-06-091-0/+12
| | | | | | | So can get cpumask_var with cpumask_clear Signed-off-by: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* cpumask: fix slab corruption caused by alloc_cpumask_var_node()Jack Steiner2009-04-021-2/+2
| | | | | | | | | | | | | | | | | | | | Fix slab corruption caused by alloc_cpumask_var_node() overwriting the tail end of an off-stack cpumask. The function zeros out cpumask bits beyond the last possible cpu. The starting point for zeroing should be the beginning of the mask offset by a byte count derived from the number of possible cpus. The offset was calculated in bits instead of bytes. This resulted in overwriting the end of the cpumask. Signed-off-by: Jack Steiner <steiner@sgi.com> Acked-by: Mike Travis <travis.sgi.com> Acked-by: Ingo Molnar <mingo@elte.hu> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: <stable@kernel.org> [2.6.29.x] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* cpumask: zero extra bits in alloc_cpumask_var_nodeRusty Russell2009-01-011-0/+8
| | | | | | | | | | | | | | Impact: extra safety checks during transition When CONFIG_CPUMASKS_OFFSTACK is set, the new cpumask_ operators only use bits up to nr_cpu_ids, not NR_CPUS. Using the old cpus_ operators on these masks can mean accessing undefined bits. After some discussion, Mike and I decided to err on the side of caution; we zero the "undefined" bits in alloc_cpumask_var_node() until all the old cpumask functions are removed. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* cpumask: fix bogus kernel-docLi Zefan2009-01-011-1/+1
| | | | | | | | | Impact: fix kernel-doc alloc_bootmem_cpumask_var() returns avoid. Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* cpumask: documentation for cpumask_var_tMike Travis2008-12-191-0/+43
| | | | | | | | | | Impact: New kerneldoc comments Additional documentation added to all the alloc_cpumask and free_cpumask functions. Signed-off-by: Mike Travis <travis@sgi.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (minor additions)
* cpumask: Add alloc_cpumask_var_node()Mike Travis2008-12-191-3/+8
| | | | | | | | | | | | | Impact: New API This will be needed in x86 code to allocate the domain and old_domain cpumasks on the same node as where the containing irq_cfg struct is allocated. (Also fixes double-dump_stack on rare CONFIG_DEBUG_PER_CPU_MAPS case) Signed-off-by: Mike Travis <travis@sgi.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (re-impl alloc_cpumask_var)
* cpumask: introduce new API, without changing anything, v3Rusty Russell2008-11-091-1/+2
| | | | | | | | | | | | | Impact: cleanup Clean up based on feedback from Andrew Morton and others: - change to inline functions instead of macros - add __init to bootmem method - add a missing debug check Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* cpumask: new API, v2Rusty Russell2008-11-071-0/+5
| | | | | | | | - add cpumask_of() - add free_bootmem_cpumask_var() Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* cpumask: introduce new API, without changing anythingRusty Russell2008-11-061-0/+73
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Impact: introduce new APIs We want to deprecate cpumasks on the stack, as we are headed for gynormous numbers of CPUs. Eventually, we want to head towards an undefined 'struct cpumask' so they can never be declared on stack. 1) New cpumask functions which take pointers instead of copies. (cpus_* -> cpumask_*) 2) Several new helpers to reduce requirements for temporary cpumasks (cpumask_first_and, cpumask_next_and, cpumask_any_and) 3) Helpers for declaring cpumasks on or offstack for large NR_CPUS (cpumask_var_t, alloc_cpumask_var and free_cpumask_var) 4) 'struct cpumask' for explicitness and to mark new-style code. 5) Make iterator functions stop at nr_cpu_ids (a runtime constant), not NR_CPUS for time efficiency and for smaller dynamic allocations in future. 6) cpumask_copy() so we can allocate less than a full cpumask eventually (for alloc_cpumask_var), and so we can eliminate the 'struct cpumask' definition eventually. 7) work_on_cpu() helper for doing task on a CPU, rather than saving old cpumask for current thread and manipulating it. 8) smp_call_function_many() which is smp_call_function_mask() except taking a cpumask pointer. Note that this patch simply introduces the new functions and leaves the obsolescent ones in place. This is to simplify the transition patches. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* x86: Add performance variants of cpumask operatorsMike Travis2008-05-231-0/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * Increase performance for systems with large count NR_CPUS by limiting the range of the cpumask operators that loop over the bits in a cpumask_t variable. This removes a large amount of wasted cpu cycles. * Add performance variants of the cpumask operators: int cpus_weight_nr(mask) Same using nr_cpu_ids instead of NR_CPUS int first_cpu_nr(mask) Number lowest set bit, or nr_cpu_ids int next_cpu_nr(cpu, mask) Next cpu past 'cpu', or nr_cpu_ids for_each_cpu_mask_nr(cpu, mask) for-loop cpu over mask using nr_cpu_ids * Modify following to use performance variants: #define num_online_cpus() cpus_weight_nr(cpu_online_map) #define num_possible_cpus() cpus_weight_nr(cpu_possible_map) #define num_present_cpus() cpus_weight_nr(cpu_present_map) #define for_each_possible_cpu(cpu) for_each_cpu_mask_nr((cpu), ...) #define for_each_online_cpu(cpu) for_each_cpu_mask_nr((cpu), ...) #define for_each_present_cpu(cpu) for_each_cpu_mask_nr((cpu), ...) * Comment added to include/linux/cpumask.h: Note: The alternate operations with the suffix "_nr" are used to limit the range of the loop to nr_cpu_ids instead of NR_CPUS when NR_CPUS > 64 for performance reasons. If NR_CPUS is <= 64 then most assembler bitmask operators execute faster with a constant range, so the operator will continue to use NR_CPUS. Another consideration is that nr_cpu_ids is initialized to NR_CPUS and isn't lowered until the possible cpus are discovered (including any disabled cpus). So early uses will span the entire range of NR_CPUS. (The net effect is that for systems with 64 or less CPU's there are no functional changes.) For inclusion into sched-devel/latest tree. Based on: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6.git + sched-devel/latest .../mingo/linux-2.6-sched-devel.git Cc: Paul Jackson <pj@sgi.com> Cc: Christoph Lameter <clameter@sgi.com> Reviewed-by: Paul Jackson <pj@sgi.com> Reviewed-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Mike Travis <travis@sgi.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* Safer nr_node_ids and nr_node_ids determination and initial valuesChristoph Lameter2007-05-071-3/+0
| | | | | | | | | | | | | | | | | | The nr_cpu_ids value is currently only calculated in smp_init. However, it may be needed before (SLUB needs it on kmem_cache_init!) and other kernel components may also want to allocate dynamically sized per cpu array before smp_init. So move the determination of possible cpus into sched_init() where we already loop over all possible cpus early in boot. Also initialize both nr_node_ids and nr_cpu_ids with the highest value they could take. If we have accidental users before these values are determined then the current valud of 0 may cause too small per cpu and per node arrays to be allocated. If it is set to the maximum possible then we only waste some memory for early boot users. Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [PATCH] Convert highest_possible_processor_id to nr_cpu_idsChristoph Lameter2007-02-201-16/+2
| | | | | | | | | | | | | | | | | We frequently need the maximum number of possible processors in order to allocate arrays for all processors. So far this was done using highest_possible_processor_id(). However, we do need the number of processors not the highest id. Moreover the number was so far dynamically calculated on each invokation. The number of possible processors does not change when the system is running. We can therefore calculate that number once. Signed-off-by: Christoph Lameter <clameter@sgi.com> Cc: Frederik Deweerdt <frederik.deweerdt@gmail.com> Cc: Neil Brown <neilb@suse.de> Cc: Trond Myklebust <trond.myklebust@fys.uio.no> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [PATCH] highest_possible_node_id() linkage fixAndrew Morton2006-10-201-16/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Qooting Adrian: - net/sunrpc/svc.c uses highest_possible_node_id() - include/linux/nodemask.h says highest_possible_node_id() is out-of-line #if MAX_NUMNODES > 1 - the out-of-line highest_possible_node_id() is in lib/cpumask.c - lib/Makefile: lib-$(CONFIG_SMP) += cpumask.o CONFIG_ARCH_DISCONTIGMEM_ENABLE=y, CONFIG_SMP=n, CONFIG_SUNRPC=y -> highest_possible_node_id() is used in net/sunrpc/svc.c CONFIG_NODES_SHIFT defined and > 0 -> include/linux/numa.h: MAX_NUMNODES > 1 -> compile error The bug is not present on architectures where ARCH_DISCONTIGMEM_ENABLE depends on NUMA (but m32r isn't the only affected architecture). So move the function into page_alloc.c Cc: Adrian Bunk <bunk@stusta.de> Cc: Paul Jackson <pj@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] cpumask: add highest_possible_node_idGreg Banks2006-10-021-0/+16
| | | | | | | | | | | cpumask: add highest_possible_node_id(), analogous to highest_possible_processor_id(). [pj@sgi.com: fix typo] Signed-off-by: Greg Banks <gnb@melbourne.sgi.com> Signed-off-by: Paul Jackson <pj@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] cpumask: uninline any_online_cpu()Andrew Morton2006-03-251-0/+12
| | | | | | | | | | | | | | | | | text data bss dec hex filename before: 3605597 1363528 363328 5332453 515de5 vmlinux after: 3605295 1363612 363200 5332107 515c8b vmlinux 218 bytes saved. Also, optimise any_online_cpu() out of existence on CONFIG_SMP=n. This function seems inefficient. Can't we simply AND the two masks, then use find_first_bit()? Cc: Paul Jackson <pj@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] cpumask: uninline highest_possible_processor_id()Andrew Morton2006-03-251-0/+17
| | | | | | | | | | | Shrinks the only caller (net/bridge/netfilter/ebtables.c) by 174 bytes. Also, optimise highest_possible_processor_id() out of existence on CONFIG_SMP=n. Cc: Paul Jackson <pj@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] cpumask: uninline next_cpu()Andrew Morton2006-03-251-0/+5
| | | | | | | | | | | | text data bss dec hex filename before: 3488027 1322496 360128 5170651 4ee5db vmlinux after: 3485112 1322480 359968 5167560 4ed9c8 vmlinux 2931 bytes saved Cc: Paul Jackson <pj@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] cpumask: uninline first_cpu()Andrew Morton2006-03-251-0/+11
text data bss dec hex filename before: 3490577 1322408 360000 5172985 4eeef9 vmlinux after: 3488027 1322496 360128 5170651 4ee5db vmlinux Cc: Paul Jackson <pj@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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