- 13 3月, 2013 1 次提交
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由 Tejun Heo 提交于
We have cpulist_parse() but not cpumask_parse(). Implement it using bitmap_parse(). bitmap_parse() is weird in that it takes @len for a string in kernel-memory which also is inconsistent with bitmap_parselist(). Make cpumask_parse() calculate the length and don't expose the inconsistency to cpumask users. Maybe we can fix up bitmap_parse() later. This will be used to expose workqueue cpumask knobs to userland via sysfs. Signed-off-by: NTejun Heo <tj@kernel.org> Cc: Rusty Russell <rusty@rustcorp.com.au>
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- 27 7月, 2012 2 次提交
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由 Alex Shi 提交于
As introduced in Rusty's commit 29c0177e, the function has no parameter @len, so need to remove it from comments to avoid kernel-doc warning: alexs@debian:~/linux-next$ scripts/kernel-doc -man include/linux/cpumask.h | split-man.pl /tmp/man .... Warning(include/linux/cpumask.h:602): Excess function parameter 'len' description in 'cpulist_parse' and correct the function name in comments to cpulist_parse. Signed-off-by: NAlex Shi <alex.shi@intel.com> Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
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由 Alex Shi 提交于
Current few cpumask functions' purposes are not quite clear. Stupid user like myself needs to dig into details for clear function purpose and return value. Add few explanation for them is helpful. Thanks for Srivatsa's comments and correction! Signed-off-by: NAlex Shi <alex.shi@intel.com> Acked-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
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- 29 3月, 2012 2 次提交
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由 Rusty Russell 提交于
These are obsolete: cpu_*_mask provides (const) pointers. Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
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由 Srivatsa S. Bhat 提交于
__any_online_cpu() is not optimal and also unnecessary. So, replace its use by faster cpumask_* operations. Signed-off-by: NSrivatsa 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: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 05 3月, 2012 1 次提交
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由 Paul Gortmaker 提交于
If a header file is making use of BUG, BUG_ON, BUILD_BUG_ON, or any other BUG variant in a static inline (i.e. not in a #define) then that header really should be including <linux/bug.h> and not just expecting it to be implicitly present. We can make this change risk-free, since if the files using these headers didn't have exposure to linux/bug.h already, they would have been causing compile failures/warnings. Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>
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- 27 7月, 2011 1 次提交
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由 KOSAKI Motohiro 提交于
cpumask_var_t has one notable difference from cpumask_t. Add the explanation. Signed-off-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Thiago Farina <tfransosi@gmail.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 25 5月, 2011 1 次提交
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由 Mike Travis 提交于
Manually adjusting the smp_affinity for IRQ's becomes unwieldy when the cpu count is large. Setting smp affinity to cpus 256 to 263 would be: echo 000000ff,00000000,00000000,00000000,00000000,00000000,00000000,00000000 > smp_affinity instead of: echo 256-263 > smp_affinity_list Think about what it looks like for cpus around say, 4088 to 4095. We already have many alternate "list" interfaces: /sys/devices/system/cpu/cpuX/indexY/shared_cpu_list /sys/devices/system/cpu/cpuX/topology/thread_siblings_list /sys/devices/system/cpu/cpuX/topology/core_siblings_list /sys/devices/system/node/nodeX/cpulist /sys/devices/pci***/***/local_cpulist Add a companion interface, smp_affinity_list to use cpu lists instead of cpu maps. This conforms to other companion interfaces where both a map and a list interface exists. This required adding a bitmap_parselist_user() function in a manner similar to the bitmap_parse_user() function. [akpm@linux-foundation.org: make __bitmap_parselist() static] Signed-off-by: NMike Travis <travis@sgi.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Jack Steiner <steiner@sgi.com> Cc: Lee Schermerhorn <lee.schermerhorn@hp.com> Cc: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 07 3月, 2010 1 次提交
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由 Heiko Carstens 提交于
Dependent on CONFIG_SMP the num_*_cpus() functions return unsigned or signed values. Let them always return unsigned values to avoid strange casts. Fixes at least one warning: kernel/kprobes.c: In function 'register_kretprobe': kernel/kprobes.c:1038: warning: comparison of distinct pointer types lacks a cast Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Masami Hiramatsu <mhiramat@redhat.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 25 2月, 2010 1 次提交
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由 Paul E. McKenney 提交于
Currently, rcu_needs_cpu() simply checks whether the current CPU has an outstanding RCU callback, which means that the last CPU to go into dyntick-idle mode might wait a few ticks for the relevant grace periods to complete. However, if all the other CPUs are in dyntick-idle mode, and if this CPU is in a quiescent state (which it is for RCU-bh and RCU-sched any time that we are considering going into dyntick-idle mode), then the grace period is instantly complete. This patch therefore repeatedly invokes the RCU grace-period machinery in order to force any needed grace periods to complete quickly. It does so a limited number of times in order to prevent starvation by an RCU callback function that might pass itself to call_rcu(). However, if any CPU other than the current one is not in dyntick-idle mode, fall back to simply checking (with fix to bug noted by Lai Jiangshan). Also, take advantage of last grace-period forcing, the opportunity to do so noted by Steve Rostedt. And apply simplified #ifdef condition suggested by Frederic Weisbecker. Signed-off-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: laijs@cn.fujitsu.com Cc: dipankar@in.ibm.com Cc: mathieu.desnoyers@polymtl.ca Cc: josh@joshtriplett.org Cc: dvhltc@us.ibm.com Cc: niv@us.ibm.com Cc: peterz@infradead.org Cc: rostedt@goodmis.org Cc: Valdis.Kletnieks@vt.edu Cc: dhowells@redhat.com LKML-Reference: <1266887105-1528-15-git-send-email-paulmck@linux.vnet.ibm.com> Signed-off-by: NIngo Molnar <mingo@elte.hu>
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- 07 12月, 2009 1 次提交
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由 Peter Zijlstra 提交于
Since (e761b772: cpu hotplug, sched: Introduce cpu_active_map and redo sched domain managment) we have cpu_active_mask which is suppose to rule scheduler migration and load-balancing, except it never (fully) did. The particular problem being solved here is a crash in try_to_wake_up() where select_task_rq() ends up selecting an offline cpu because select_task_rq_fair() trusts the sched_domain tree to reflect the current state of affairs, similarly select_task_rq_rt() trusts the root_domain. However, the sched_domains are updated from CPU_DEAD, which is after the cpu is taken offline and after stop_machine is done. Therefore it can race perfectly well with code assuming the domains are right. Cure this by building the domains from cpu_active_mask on CPU_DOWN_PREPARE. Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <new-submission> Signed-off-by: NIngo Molnar <mingo@elte.hu>
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- 24 9月, 2009 4 次提交
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由 Rusty Russell 提交于
The new ones have pretty kerneldoc. Move the old ones to the end to avoid confusing people. Signed-off-by: NRusty Russell <rusty@rustcorp.com.au> Cc: benh@kernel.crashing.org
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由 Rusty Russell 提交于
We're not forcing removal of the old cpu_ functions, but we might as well delete the now-unused ones. Especially CPUMASK_ALLOC and friends. I actually got a phone call (!) from a hacker who thought I had introduced them as the new cpumask API. He seemed bewildered that I had lost all taste. Signed-off-by: NRusty Russell <rusty@rustcorp.com.au> Cc: benh@kernel.crashing.org
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由 Rusty Russell 提交于
It's only defined for NR_CPUS > BITS_PER_LONG; cpu_all_mask is always defined (and const). Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
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由 Rusty Russell 提交于
(Thanks to Al Viro for reminding me of this, via Ingo) CPU_MASK_ALL is the (deprecated) "all bits set" cpumask, defined as so: #define CPU_MASK_ALL (cpumask_t) { { ... } } Taking the address of such a temporary is questionable at best, unfortunately 321a8e9d (cpumask: add CPU_MASK_ALL_PTR macro) added CPU_MASK_ALL_PTR: #define CPU_MASK_ALL_PTR (&CPU_MASK_ALL) Which formalizes this practice. One day gcc could bite us over this usage (though we seem to have gotten away with it so far). Now all callers are removed, we kill it. Signed-off-by: NRusty Russell <rusty@rustcorp.com.au> Acked-by: NIngo Molnar <mingo@elte.hu> Reported-by: NAl Viro <viro@zeniv.linux.org.uk> Cc: Mike Travis <travis@sgi.com>
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- 23 9月, 2009 1 次提交
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由 Xiao Guangrong 提交于
This patch can remove spinlock from struct call_function_data, the reasons are below: 1: add a new interface for cpumask named cpumask_test_and_clear_cpu(), it can atomically test and clear specific cpu, we can use it instead of cpumask_test_cpu() and cpumask_clear_cpu() and no need data->lock to protect those in generic_smp_call_function_interrupt(). 2: in smp_call_function_many(), after csd_lock() return, the current's cfd_data is deleted from call_function list, so it not have race between other cpus, then cfs_data is only used in smp_call_function_many() that must disable preemption and not from a hardware interrupthandler or from a bottom half handler to call, only the correspond cpu can use it, so it not have race in current cpu, no need cfs_data->lock to protect it. 3: after 1 and 2, cfs_data->lock is only use to protect cfs_data->refs in generic_smp_call_function_interrupt(), so we can define cfs_data->refs to atomic_t, and no need cfs_data->lock any more. Signed-off-by: NXiao Guangrong <xiaoguangrong@cn.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Nick Piggin <nickpiggin@yahoo.com.au> Cc: Peter Zijlstra <peterz@infradead.org> Acked-by: NRusty Russell <rusty@rustcorp.com.au> [akpm@linux-foundation.org: use atomic_dec_return()] Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 22 8月, 2009 1 次提交
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由 Linus Torvalds 提交于
When 'and'ing two bitmasks (where 'andnot' is a variation on it), some cases want to know whether the result is the empty set or not. In particular, the TLB IPI sending code wants to do cpumask operations and determine if there are any CPU's left in the final set. So this just makes the bitmask (and cpumask) functions return a boolean for whether the result has any bits set. Cc: stable@kernel.org (2.6.30, needed by TLB shootdown fix) Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 09 6月, 2009 1 次提交
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由 Yinghai Lu 提交于
So can get cpumask_var with cpumask_clear Signed-off-by: NYinghai Lu <yinghai@kernel.org> Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
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- 01 1月, 2009 1 次提交
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由 Rusty Russell 提交于
Impact: new debug CONFIG options This helps find unconverted code. It currently breaks compile horribly, but we never wanted a flag day so that's expected. Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
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- 30 12月, 2008 3 次提交
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由 Rusty Russell 提交于
They're only for use in boot/cpu hotplug code anyway, and this avoids the use of deprecated cpu_*_map. Stephen Rothwell points out that gcc 4.2.4 (on powerpc at least) didn't like the cast away of const anyway: include/linux/cpumask.h: In function 'set_cpu_possible': include/linux/cpumask.h:1052: warning: passing argument 2 of 'cpumask_set_cpu' discards qualifiers from pointer target type So this kills two birds with one stone. Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
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由 Rusty Russell 提交于
Changes: 1) cpumask_t to struct cpumask, 2) cpus_weight_nr to cpumask_weight, 3) cpu_isset to cpumask_test_cpu, 4) ->bits to cpumask_bits() 5) cpu_*_map to cpu_*_mask. 6) for_each_cpu_mask_nr to for_each_cpu Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
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由 Rusty Russell 提交于
Impact: cleanup This implements the obsolescent cpu_online_map in terms of cpu_online_mask, rather than the other way around. Same for the other maps. The documentation comments are also updated to refer to _mask rather than _map. Signed-off-by: NRusty Russell <rusty@rustcorp.com.au> Signed-off-by: NMike Travis <travis@sgi.com>
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- 19 12月, 2008 1 次提交
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由 Mike Travis 提交于
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: NMike Travis <travis@sgi.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (re-impl alloc_cpumask_var)
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- 13 12月, 2008 2 次提交
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由 Rusty Russell 提交于
Impact: futureproof as we convert more code to new APIs The old cpumask operators treat all NR_CPUS bits as relevent, the new ones use nr_cpumask_bits. For large NR_CPUS and small nr_cpu_ids, this makes a difference. However, mixing the two can cause problems with undefined bits. An arch which sets CONFIG_CPUMASK_OFFSTACK should have converted across to the new operators, so it's safe in that case. (Thanks to Stephen Rothwell for bisecting the initial unused-bits bug, and Mike Travis for this solution). Signed-off-by: NRusty Russell <rusty@rustcorp.com.au> Cc: Mike Travis <travis@sgi.com>
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由 Rusty Russell 提交于
cpumask: change cpumask_scnprintf, cpumask_parse_user, cpulist_parse, and cpulist_scnprintf to take pointers. Impact: change calling convention of existing cpumask APIs Most cpumask functions started with cpus_: these have been replaced by cpumask_ ones which take struct cpumask pointers as expected. These four functions don't have good replacement names; fortunately they're rarely used, so we just change them over. Signed-off-by: NRusty Russell <rusty@rustcorp.com.au> Signed-off-by: NMike Travis <travis@sgi.com> Acked-by: NIngo Molnar <mingo@elte.hu> Cc: paulus@samba.org Cc: mingo@redhat.com Cc: tony.luck@intel.com Cc: ralf@linux-mips.org Cc: Greg Kroah-Hartman <gregkh@suse.de> Cc: cl@linux-foundation.org Cc: srostedt@redhat.com
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- 10 11月, 2008 1 次提交
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由 Rusty Russell 提交于
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: NRusty Russell <rusty@rustcorp.com.au> Signed-off-by: NIngo Molnar <mingo@elte.hu>
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- 07 11月, 2008 1 次提交
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由 Rusty Russell 提交于
- add cpumask_of() - add free_bootmem_cpumask_var() Signed-off-by: NRusty Russell <rusty@rustcorp.com.au> Signed-off-by: NIngo Molnar <mingo@elte.hu>
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- 06 11月, 2008 1 次提交
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由 Rusty Russell 提交于
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: NRusty Russell <rusty@rustcorp.com.au> Signed-off-by: NIngo Molnar <mingo@elte.hu>
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- 31 7月, 2008 1 次提交
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由 Stephen Rothwell 提交于
when you take the address of the result. Noticed on a sparc64 compile using a version 3.4.5 cross compiler. kernel/time/tick-common.c: In function `tick_check_new_device': kernel/time/tick-common.c:210: error: invalid lvalue in unary `&' ... Just make it a regular expression. Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au> Acked-by: NIngo Molnar <mingo@elte.hu> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 29 7月, 2008 1 次提交
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由 Linus Torvalds 提交于
Clean up and optimize cpumask_of_cpu(), by sharing all the zero words. Instead of stupidly generating all possible i=0...NR_CPUS 2^i patterns creating a huge array of constant bitmasks, realize that the zero words can be shared. In other words, on a 64-bit architecture, we only ever need 64 of these arrays - with a different bit set in one single world (with enough zero words around it so that we can create any bitmask by just offsetting in that big array). And then we just put enough zeroes around it that we can point every single cpumask to be one of those things. So when we have 4k CPU's, instead of having 4k arrays (of 4k bits each, with one bit set in each array - 2MB memory total), we have exactly 64 arrays instead, each 8k bits in size (64kB total). And then we just point cpumask(n) to the right position (which we can calculate dynamically). Once we have the right arrays, getting "cpumask(n)" ends up being: static inline const cpumask_t *get_cpu_mask(unsigned int cpu) { const unsigned long *p = cpu_bit_bitmap[1 + cpu % BITS_PER_LONG]; p -= cpu / BITS_PER_LONG; return (const cpumask_t *)p; } This brings other advantages and simplifications as well: - we are not wasting memory that is just filled with a single bit in various different places - we don't need all those games to re-create the arrays in some dense format, because they're already going to be dense enough. if we compile a kernel for up to 4k CPU's, "wasting" that 64kB of memory is a non-issue (especially since by doing this "overlapping" trick we probably get better cache behaviour anyway). [ mingo@elte.hu: Converted Linus's mails into a commit. See: http://lkml.org/lkml/2008/7/27/156 http://lkml.org/lkml/2008/7/28/320 Also applied a family filter - which also has the side-effect of leaving out the bits where Linus calls me an idio... Oh, never mind ;-) ] Signed-off-by: NIngo Molnar <mingo@elte.hu> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Mike Travis <travis@sgi.com> Signed-off-by: NIngo Molnar <mingo@elte.hu>
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- 26 7月, 2008 1 次提交
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由 Mike Travis 提交于
If an arch doesn't define cpumask_of_cpu_map, create a generic statically-initialized one for them. This allows removal of the buggy cpumask_of_cpu() macro (&cpumask_of_cpu() gives address of out-of-scope var). An arch with NR_CPUS of 4096 probably wants to allocate this itself based on the actual number of CPUs, since otherwise they're using 2MB of rodata (1024 cpus means 128k). That's what CONFIG_HAVE_CPUMASK_OF_CPU_MAP is for (only x86/64 does so at the moment). In future as we support more CPUs, we'll need to resort to a get_cpu_map()/put_cpu_map() allocation scheme. Signed-off-by: NMike Travis <travis@sgi.com> Signed-off-by: NRusty Russell <rusty@rustcorp.com.au> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Jack Steiner <steiner@sgi.com> Signed-off-by: NIngo Molnar <mingo@elte.hu>
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- 20 7月, 2008 1 次提交
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由 Mike Travis 提交于
* Rename CPUMASK_VAR --> CPUMASK_PTR (and simplify) * Fix a semantic error in CPUMASK_ALLOC * Add a bit of commentry to cpumask.h Signed-off-by: NMike Travis <travis@sgi.com> Signed-off-by: NIngo Molnar <mingo@elte.hu>
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- 19 7月, 2008 2 次提交
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由 Mike Travis 提交于
* Provide a generic set of CPUMASK_ALLOC macros patterned after the SCHED_CPUMASK_ALLOC macros. This is used where multiple cpumask_t variables are declared on the stack to reduce the amount of stack space required. Signed-off-by: NMike Travis <travis@sgi.com> Signed-off-by: NIngo Molnar <mingo@elte.hu>
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由 Mike Travis 提交于
* This patch replaces the dangerous lvalue version of cpumask_of_cpu with new cpumask_of_cpu_ptr macros. These are patterned after the node_to_cpumask_ptr macros. In general terms, if there is a cpumask_of_cpu_map[] then a pointer to the cpumask_of_cpu_map[cpu] entry is used. The cpumask_of_cpu_map is provided when there is a large NR_CPUS count, reducing greatly the amount of code generated and stack space used for cpumask_of_cpu(). The pointer to the cpumask_t value is needed for calling set_cpus_allowed_ptr() to reduce the amount of stack space needed to pass the cpumask_t value. If there isn't a cpumask_of_cpu_map[], then a temporary variable is declared and filled in with value from cpumask_of_cpu(cpu) as well as a pointer variable pointing to this temporary variable. Afterwards, the pointer is used to reference the cpumask value. The compiler will optimize out the extra dereference through the pointer as well as the stack space used for the pointer, resulting in identical code. A good example of the orthogonal usages is in net/sunrpc/svc.c: case SVC_POOL_PERCPU: { unsigned int cpu = m->pool_to[pidx]; cpumask_of_cpu_ptr(cpumask, cpu); *oldmask = current->cpus_allowed; set_cpus_allowed_ptr(current, cpumask); return 1; } case SVC_POOL_PERNODE: { unsigned int node = m->pool_to[pidx]; node_to_cpumask_ptr(nodecpumask, node); *oldmask = current->cpus_allowed; set_cpus_allowed_ptr(current, nodecpumask); return 1; } Signed-off-by: NMike Travis <travis@sgi.com> Signed-off-by: NIngo Molnar <mingo@elte.hu>
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- 18 7月, 2008 1 次提交
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由 Max Krasnyansky 提交于
This is based on Linus' idea of creating cpu_active_map that prevents scheduler load balancer from migrating tasks to the cpu that is going down. It allows us to simplify domain management code and avoid unecessary domain rebuilds during cpu hotplug event handling. Please ignore the cpusets part for now. It needs some more work in order to avoid crazy lock nesting. Although I did simplfy and unify domain reinitialization logic. We now simply call partition_sched_domains() in all the cases. This means that we're using exact same code paths as in cpusets case and hence the test below cover cpusets too. Cpuset changes to make rebuild_sched_domains() callable from various contexts are in the separate patch (right next after this one). This not only boots but also easily handles while true; do make clean; make -j 8; done and while true; do on-off-cpu 1; done at the same time. (on-off-cpu 1 simple does echo 0/1 > /sys/.../cpu1/online thing). Suprisingly the box (dual-core Core2) is quite usable. In fact I'm typing this on right now in gnome-terminal and things are moving just fine. Also this is running with most of the debug features enabled (lockdep, mutex, etc) no BUG_ONs or lockdep complaints so far. I believe I addressed all of the Dmitry's comments for original Linus' version. I changed both fair and rt balancer to mask out non-active cpus. And replaced cpu_is_offline() with !cpu_active() in the main scheduler code where it made sense (to me). Signed-off-by: NMax Krasnyanskiy <maxk@qualcomm.com> Acked-by: NLinus Torvalds <torvalds@linux-foundation.org> Acked-by: NPeter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: NGregory Haskins <ghaskins@novell.com> Cc: dmitry.adamushko@gmail.com Cc: pj@sgi.com Signed-off-by: NIngo Molnar <mingo@elte.hu>
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- 06 7月, 2008 1 次提交
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由 Ingo Molnar 提交于
This reverts commit acb7669c. the wrappers are not needed anymore. Signed-off-by: NIngo Molnar <mingo@elte.hu>
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- 05 7月, 2008 1 次提交
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由 Stephen Rothwell 提交于
In linux-next there is a commit ("x86: Add performance variants of cpumask operators") which, as part of the 4096 cpu support work adds some new APIs for dealing with cpu masks. Add trivial versions of these now so that subsystems can update in a timely manner and avoid conflicts in linux-next and the next merge window. Cc: Mike Travis <travis@sgi.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 24 5月, 2008 2 次提交
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由 Alexander van Heukelum 提交于
The for_each_cpu_mask loop is used quite often in the kernel. It makes use of two functions: first_cpu and next_cpu. This patch changes for_each_cpu_mask to use only the latter. Because next_cpu finds the next eligible cpu _after_ the given one, the iteration variable has to be initialized to -1 and next_cpu has to be called with this value before the first iteration. An x86_64 defconfig kernel (from sched/latest) is about 2500 bytes smaller with this patch applied: text data bss dec hex filename 6222517 917952 749932 7890401 7865e1 vmlinux.orig 6219922 917952 749932 7887806 785bbe vmlinux The same size reduction is seen for defconfig+MAXSMP text data bss dec hex filename 6241772 2563968 1492716 10298456 9d2458 vmlinux.orig 6239211 2563968 1492716 10295895 9d1a57 vmlinux Signed-off-by: NAlexander van Heukelum <heukelum@fastmail.fm> Signed-off-by: NIngo Molnar <mingo@elte.hu> Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
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由 Mike Travis 提交于
* 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: NPaul Jackson <pj@sgi.com> Reviewed-by: NChristoph Lameter <clameter@sgi.com> Signed-off-by: NMike Travis <travis@sgi.com> Signed-off-by: NIngo Molnar <mingo@elte.hu>
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- 13 5月, 2008 1 次提交
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由 Paul Jackson 提交于
They aren't used. They were briefly used as part of some other patches to provide an alternative format for displaying some /proc and /sys cpumasks. They probably should have been removed when those other patches were dropped, in favor of a different solution. Signed-off-by: NPaul Jackson <pj@sgi.com> Cc: "Mike Travis" <travis@sgi.com> Cc: "Bert Wesarg" <bert.wesarg@googlemail.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: WANG Cong <xiyou.wangcong@gmail.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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