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* Merge branch 'for-linus' into for-nextTejun Heo2009-12-084-60/+132
|\ | | | | | | | | Conflicts: mm/percpu.c
| * percpu: add missing per_cpu_ptr_to_phys() definition for UPTejun Heo2009-12-021-0/+5
| | | | | | | | | | | | | | | | | | | | Commit 3b034b0d084221596bf35c8d893e1d4d5477b9cc implemented per_cpu_ptr_to_phys() but forgot to add UP definition. Add UP definition which is simple wrapper around __pa(). Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Reported-by: Randy Dunlap <randy.dunlap@oracle.com>
| * percpu: Fix kdump failure if booted with percpu_alloc=pageVivek Goyal2009-11-253-1/+24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | o kdump functionality reserves a per cpu area at boot time and exports the physical address of that area to user space through sys interface. This area stores some dump related information like cpu register states etc at the time of crash. o We were assuming that per cpu area always come from linearly mapped meory region and using __pa() to determine physical address. With percpu_alloc=page, per cpu area can come from vmalloc region also and __pa() breaks. o This patch implments a new function to convert per cpu address to physical address. Before the patch, crash_notes addresses looked as follows. cpu0 60fffff49800 cpu1 60fffff60800 cpu2 60fffff77800 These are bogus phsyical addresses. After the patch, address are following. cpu0 13eb44000 cpu1 13eb43000 cpu2 13eb42000 cpu3 13eb41000 These look fine. I got 4G of memory and /proc/iomem tell me following. 100000000-13fffffff : System RAM tj: * added missing asm/io.h include reported by Stephen Rothwell * repositioned per_cpu_ptr_phys() in percpu.c and added comment. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au>
| * percpu: restructure pcpu_extend_area_map() to fix bugs and improve readabilityTejun Heo2009-11-131-40/+81
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | pcpu_extend_area_map() had the following two bugs. * It should return 1 if pcpu_lock was dropped and reacquired but it returned 0. This could lead to oops if free_percpu() races with area map extension. * pcpu_mem_free() was called under pcpu_lock. pcpu_mem_free() might end up calling vfree() which isn't IRQ safe. This could lead to deadlock through lock order inversion via IRQ. In addition, Linus pointed out that the temporary lock dropping and subtle three-way return value of pcpu_extend_area_map() was very ugly and suggested to split the function into two - pcpu_need_to_extend() and pcpu_extend_area_map(). This patch restructures pcpu_extend_area_map() as suggested and fixes the two bugs. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Ingo Molnar <mingo@elte.hu>
| * sched: move rq_weight data array out of .percpuJiri Kosina2009-10-291-11/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 34d76c41 introduced percpu array update_shares_data, size of which being proportional to NR_CPUS. Unfortunately this blows up ia64 for large NR_CPUS configuration, as ia64 allows only 64k for .percpu section. Fix this by allocating this array dynamically and keep only pointer to it percpu. The per-cpu handling doesn't impose significant performance penalty on potentially contented path in tg_shares_up(). ... ffffffff8104337c: 65 48 8b 14 25 20 cd mov %gs:0xcd20,%rdx ffffffff81043383: 00 00 ffffffff81043385: 48 c7 c0 00 e1 00 00 mov $0xe100,%rax ffffffff8104338c: 48 c7 45 a0 00 00 00 movq $0x0,-0x60(%rbp) ffffffff81043393: 00 ffffffff81043394: 48 c7 45 a8 00 00 00 movq $0x0,-0x58(%rbp) ffffffff8104339b: 00 ffffffff8104339c: 48 01 d0 add %rdx,%rax ffffffff8104339f: 49 8d 94 24 08 01 00 lea 0x108(%r12),%rdx ffffffff810433a6: 00 ffffffff810433a7: b9 ff ff ff ff mov $0xffffffff,%ecx ffffffff810433ac: 48 89 45 b0 mov %rax,-0x50(%rbp) ffffffff810433b0: bb 00 04 00 00 mov $0x400,%ebx ffffffff810433b5: 48 89 55 c0 mov %rdx,-0x40(%rbp) ... After: ... ffffffff8104337c: 65 8b 04 25 28 cd 00 mov %gs:0xcd28,%eax ffffffff81043383: 00 ffffffff81043384: 48 98 cltq ffffffff81043386: 49 8d bc 24 08 01 00 lea 0x108(%r12),%rdi ffffffff8104338d: 00 ffffffff8104338e: 48 8b 15 d3 7f 76 00 mov 0x767fd3(%rip),%rdx # ffffffff817ab368 <update_shares_data> ffffffff81043395: 48 8b 34 c5 00 ee 6d mov -0x7e921200(,%rax,8),%rsi ffffffff8104339c: 81 ffffffff8104339d: 48 c7 45 a0 00 00 00 movq $0x0,-0x60(%rbp) ffffffff810433a4: 00 ffffffff810433a5: b9 ff ff ff ff mov $0xffffffff,%ecx ffffffff810433aa: 48 89 7d c0 mov %rdi,-0x40(%rbp) ffffffff810433ae: 48 c7 45 a8 00 00 00 movq $0x0,-0x58(%rbp) ffffffff810433b5: 00 ffffffff810433b6: bb 00 04 00 00 mov $0x400,%ebx ffffffff810433bb: 48 01 f2 add %rsi,%rdx ffffffff810433be: 48 89 55 b0 mov %rdx,-0x50(%rbp) ... Signed-off-by: Jiri Kosina <jkosina@suse.cz> Acked-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Tejun Heo <tj@kernel.org>
| * percpu: allow pcpu_alloc() to be called with IRQs offJiri Kosina2009-10-291-13/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | pcpu_alloc() and pcpu_extend_area_map() perform a series of spin_lock_irq()/spin_unlock_irq() calls, which make them unsafe with respect to being called from contexts which have IRQs off. This patch converts the code to perform save/restore of flags instead, making pcpu_alloc() (or __alloc_percpu() respectively) to be called from early kernel startup stage, where IRQs are off. This is needed for proper initialization of per-cpu rq_weight data from sched_init(). tj: added comment explaining why irqsave/restore is used in alloc path. Signed-off-by: Jiri Kosina <jkosina@suse.cz> Acked-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Tejun Heo <tj@kernel.org>
* | percpu: make misc percpu symbols uniqueTejun Heo2009-10-294-45/+42
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch updates misc percpu related symbols such that percpu symbols are unique and don't clash with local symbols. This serves two purposes of decreasing the possibility of global percpu symbol collision and allowing dropping per_cpu__ prefix from percpu symbols. * drivers/crypto/padlock-aes.c: s/last_cword/paes_last_cword/ * drivers/lguest/x86/core.c: s/last_cpu/lg_last_cpu/ * drivers/s390/net/netiucv.c: rename the variable used in a macro to avoid clashing with percpu symbol * arch/mn10300/kernel/kprobes.c: replace current_ prefix with cur_ for static variables. Please note that percpu symbol current_kprobe can't be changed as it's used by generic code. Partly based on Rusty Russell's "alloc_percpu: rename percpu vars which cause name clashes" patch. Signed-off-by: Tejun Heo <tj@kernel.org> Reviewed-by: Christoph Lameter <cl@linux-foundation.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Chuck Ebbert <cebbert@redhat.com> Cc: David Howells <dhowells@redhat.com> Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> Cc: David S. Miller <davem@davemloft.net> Cc: Masami Hiramatsu <mhiramat@redhat.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: linux390@de.ibm.com
* | percpu: make percpu symbols in ia64 uniqueTejun Heo2009-10-298-16/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch updates percpu related symbols in ia64 such that percpu symbols are unique and don't clash with local symbols. This serves two purposes of decreasing the possibility of global percpu symbol collision and allowing dropping per_cpu__ prefix from percpu symbols. * arch/ia64/kernel/setup.c: s/cpu_info/ia64_cpu_info/ Partly based on Rusty Russell's "alloc_percpu: rename percpu vars which cause name clashes" patch. Signed-off-by: Tejun Heo <tj@kernel.org> Reviewed-by: Christoph Lameter <cl@linux-foundation.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Tony Luck <tony.luck@intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: linux-ia64@vger.kernel.org
* | percpu: make percpu symbols in powerpc uniqueTejun Heo2009-10-296-15/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch updates percpu related symbols in powerpc such that percpu symbols are unique and don't clash with local symbols. This serves two purposes of decreasing the possibility of global percpu symbol collision and allowing dropping per_cpu__ prefix from percpu symbols. * arch/powerpc/kernel/perf_callchain.c: s/callchain/cpu_perf_callchain/ * arch/powerpc/kernel/setup-common.c: s/pvr/cpu_pvr/ * arch/powerpc/platforms/pseries/dtl.c: s/dtl/cpu_dtl/ * arch/powerpc/platforms/cell/interrupt.c: s/iic/cpu_iic/ Partly based on Rusty Russell's "alloc_percpu: rename percpu vars which cause name clashes" patch. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Paul Mackerras <paulus@samba.org> Cc: linuxppc-dev@ozlabs.org
* | percpu: make percpu symbols in x86 uniqueTejun Heo2009-10-295-80/+79
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch updates percpu related symbols in x86 such that percpu symbols are unique and don't clash with local symbols. This serves two purposes of decreasing the possibility of global percpu symbol collision and allowing dropping per_cpu__ prefix from percpu symbols. * arch/x86/kernel/cpu/common.c: rename local variable to avoid collision * arch/x86/kvm/svm.c: s/svm_data/sd/ for local variables to avoid collision * arch/x86/kernel/cpu/cpu_debug.c: s/cpu_arr/cpud_arr/ s/priv_arr/cpud_priv_arr/ s/cpu_priv_count/cpud_priv_count/ * arch/x86/kernel/cpu/intel_cacheinfo.c: s/cpuid4_info/ici_cpuid4_info/ s/cache_kobject/ici_cache_kobject/ s/index_kobject/ici_index_kobject/ * arch/x86/kernel/ds.c: s/cpu_context/cpu_ds_context/ Partly based on Rusty Russell's "alloc_percpu: rename percpu vars which cause name clashes" patch. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: (kvm) Avi Kivity <avi@redhat.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@elte.hu> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: x86@kernel.org
* | percpu: make percpu symbols in xen uniqueTejun Heo2009-10-294-107/+111
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch updates percpu related symbols in xen such that percpu symbols are unique and don't clash with local symbols. This serves two purposes of decreasing the possibility of global percpu symbol collision and allowing dropping per_cpu__ prefix from percpu symbols. * arch/x86/xen/smp.c, arch/x86/xen/time.c, arch/ia64/xen/irq_xen.c: add xen_ prefix to percpu variables * arch/ia64/xen/time.c: add xen_ prefix to percpu variables, drop processed_ prefix and make them static Partly based on Rusty Russell's "alloc_percpu: rename percpu vars which cause name clashes" patch. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Jeremy Fitzhardinge <jeremy@xensource.com> Cc: Chris Wright <chrisw@sous-sol.org>
* | percpu: make percpu symbols in cpufreq uniqueTejun Heo2009-10-293-28/+28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch updates percpu related symbols in cpufreq such that percpu symbols are unique and don't clash with local symbols. This serves two purposes of decreasing the possibility of global percpu symbol collision and allowing dropping per_cpu__ prefix from percpu symbols. * drivers/cpufreq/cpufreq.c: s/policy_cpu/cpufreq_policy_cpu/ * drivers/cpufreq/freq_table.c: s/show_table/cpufreq_show_table/ * arch/x86/kernel/cpu/cpufreq/acpi-cpufreq.c: s/drv_data/acfreq_data/ s/old_perf/acfreq_old_perf/ Partly based on Rusty Russell's "alloc_percpu: rename percpu vars which cause name clashes" patch. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Rusty Russell <rusty@rustcorp.com.au>
* | percpu: make percpu symbols in oprofile uniqueTejun Heo2009-10-293-14/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch updates percpu related symbols in oprofile such that percpu symbols are unique and don't clash with local symbols. This serves two purposes of decreasing the possibility of global percpu symbol collision and allowing dropping per_cpu__ prefix from percpu symbols. * drivers/oprofile/cpu_buffer.c: s/cpu_buffer/op_cpu_buffer/ Partly based on Rusty Russell's "alloc_percpu: rename percpu vars which cause name clashes" patch. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Robert Richter <robert.richter@amd.com> Cc: Rusty Russell <rusty@rustcorp.com.au>
* | percpu: make percpu symbols in tracer uniqueTejun Heo2009-10-292-27/+28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch updates percpu related symbols in kernel tracer such that percpu symbols are unique and don't clash with local symbols. This serves two purposes of decreasing the possibility of global percpu symbol collision and allowing dropping per_cpu__ prefix from percpu symbols. * kernel/trace/trace.c: s/max_data/max_tr_data/ * kernel/trace/trace_hw_branches: s/tracer/hwb_tracer/, s/buffer/hwb_buffer/ Partly based on Rusty Russell's "alloc_percpu: rename percpu vars which cause name clashes" patch. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Steven Rostedt <rostedt@goodmis.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com>
* | percpu: make percpu symbols under kernel/ and mm/ uniqueTejun Heo2009-10-297-56/+57
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch updates percpu related symbols under kernel/ and mm/ such that percpu symbols are unique and don't clash with local symbols. This serves two purposes of decreasing the possibility of global percpu symbol collision and allowing dropping per_cpu__ prefix from percpu symbols. * kernel/lockdep.c: s/lock_stats/cpu_lock_stats/ * kernel/sched.c: s/init_rq_rt/init_rt_rq_var/ (any better idea?) s/sched_group_cpus/sched_groups/ * kernel/softirq.c: s/ksoftirqd/run_ksoftirqd/a * kernel/softlockup.c: s/(*)_timestamp/softlockup_\1_ts/ s/watchdog_task/softlockup_watchdog/ s/timestamp/ts/ for local variables * kernel/time/timer_stats: s/lookup_lock/tstats_lookup_lock/ * mm/slab.c: s/reap_work/slab_reap_work/ s/reap_node/slab_reap_node/ * mm/vmstat.c: local variable changed to avoid collision with vmstat_work Partly based on Rusty Russell's "alloc_percpu: rename percpu vars which cause name clashes" patch. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: (slab/vmstat) Christoph Lameter <cl@linux-foundation.org> Reviewed-by: Christoph Lameter <cl@linux-foundation.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Ingo Molnar <mingo@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Nick Piggin <npiggin@suse.de>
* | percpu: remove some sparse warningsTejun Heo2009-10-294-37/+39
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Make the following changes to remove some sparse warnings. * Make DEFINE_PER_CPU_SECTION() declare __pcpu_unique_* before defining it. * Annotate pcpu_extend_area_map() that it is entered with pcpu_lock held, releases it and then reacquires it. * Make percpu related macros use unique nested variable names. * While at it, add pcpu prefix to __size_call[_return]() macros as to-be-implemented sparse annotations will add percpu specific stuff to these macros. Signed-off-by: Tejun Heo <tj@kernel.org> Reviewed-by: Christoph Lameter <cl@linux-foundation.org> Cc: Rusty Russell <rusty@rustcorp.com.au>
* | percpu: make alloc_percpu() handle array typesTejun Heo2009-10-291-2/+2
| | | | | | | | | | | | | | | | | | alloc_percpu() couldn't handle array types like "int [100]" due to the way return type was casted. Fix it by using typeof() instead. Signed-off-by: Tejun Heo <tj@kernel.org> Reviewed-by: Frederic Weisbecker <fweisbec@gmail.com> Reviewed-by: Christoph Lameter <cl@linux-foundation.org>
* | vmalloc: fix use of non-existent percpu variable in put_cpu_var()Tejun Heo2009-10-291-2/+2
| | | | | | | | | | | | | | | | | | vmalloc used non-existent percpu variable vmap_cpu_blocks instead of the intended vmap_block_queue. This went unnoticed because put_cpu_var() didn't evaluate the parameter. Fix it. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Nick Piggin <npiggin@suse.de>
* | this_cpu: Use this_cpu_xx in trace_functions_graph.cTejun Heo2009-10-131-2/+2
| | | | | | | | | | | | | | | | | | | | ftrace_cpu_disabled usage in trace_functions_graph.c were left out during this_cpu_xx conversion in commit 9288f99a causing compile failure. Convert them. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Christoph Lameter <cl@linux-foundation.org>
* | this_cpu: Use this_cpu_xx for ftraceChristoph Lameter2009-10-122-5/+5
| | | | | | | | | | | | | | | | | | this_cpu_xx can reduce the instruction count here and also avoid address arithmetic. Signed-off-by: Christoph Lameter <cl@linux-foundation.org> Acked-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Tejun Heo <tj@kernel.org>
* | this_cpu: Use this_cpu_xx in nmi handlingChristoph Lameter2009-10-122-8/+8
| | | | | | | | | | | | | | this_cpu_inc/dec reduces the number of instructions needed. Signed-off-by: Christoph Lameter <cl@linux-foundation.org> Signed-off-by: Tejun Heo <tj@kernel.org>
* | Merge branch 'for-linus' into for-nextTejun Heo2009-10-121-2/+3
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| * percpu: fix compile warningsTejun Heo2009-10-121-2/+3
| | | | | | | | | | | | | | | | | | | | Fix the following two compile warnings which show up on i386. mm/percpu.c:1873: warning: comparison of distinct pointer types lacks a cast mm/percpu.c:1879: warning: format '%lx' expects type 'long unsigned int', but argument 2 has type 'size_t' Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Randy Dunlap <randy.dunlap@oracle.com>
* | this_cpu: Use this_cpu operations in RCUChristoph Lameter2009-10-031-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | RCU does not do dynamic allocations but it increments per cpu variables a lot. These instructions results in a move to a register and then back to memory. This patch will make it use the inc/dec instructions on x86 that do not need a register. Acked-by: Tejun Heo <tj@kernel.org> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Christoph Lameter <cl@linux-foundation.org> Signed-off-by: Tejun Heo <tj@kernel.org>
* | this_cpu: Use this_cpu ops for VM statisticsChristoph Lameter2009-10-031-6/+4
| | | | | | | | | | | | | | | | | | | | Using per cpu atomics for the vm statistics reduces their overhead. And in the case of x86 we are guaranteed that they will never race even in the lax form used for vm statistics. Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Christoph Lameter <cl@linux-foundation.org> Signed-off-by: Tejun Heo <tj@kernel.org>
* | this_cpu: Use this_cpu_ptr in crypto subsystemChristoph Lameter2009-10-031-1/+1
| | | | | | | | | | | | | | | | | | | | | | Just a slight optimization that removes one array lookup. The processor number is needed for other things as well so the get/put_cpu cannot be removed. Acked-by: Tejun Heo <tj@kernel.org> Cc: Huang Ying <ying.huang@intel.com> Signed-off-by: Christoph Lameter <cl@linux-foundation.org> Signed-off-by: Tejun Heo <tj@kernel.org>
* | this_cpu: xfs_icsb_modify_counters does not need "cpu" variableChristoph Lameter2009-10-031-6/+6
| | | | | | | | | | | | | | | | | | | | | | The xfs_icsb_modify_counters() function no longer needs the cpu variable if we use this_cpu_ptr() and we can get rid of get/put_cpu(). Acked-by: Tejun Heo <tj@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Olaf Weber <olaf@sgi.com> Signed-off-by: Christoph Lameter <cl@linux-foundation.org> Signed-off-by: Tejun Heo <tj@kernel.org>
* | this_cpu: Eliminate get/put_cpuChristoph Lameter2009-10-032-27/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There are cases where we can use this_cpu_ptr and as the result of using this_cpu_ptr() we no longer need to determine the currently executing cpu. In those places no get/put_cpu combination is needed anymore. The local cpu variable can be eliminated. Preemption still needs to be disabled and enabled since the modifications of the per cpu variables is not atomic. There may be multiple per cpu variables modified and those must all be from the same processor. Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Acked-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Tejun Heo <tj@kernel.org> cc: Eric Biederman <ebiederm@aristanetworks.com> cc: Stephen Hemminger <shemminger@vyatta.com> cc: David L Stevens <dlstevens@us.ibm.com> Signed-off-by: Christoph Lameter <cl@linux-foundation.org> Signed-off-by: Tejun Heo <tj@kernel.org>
* | this_cpu: Straight transformationsChristoph Lameter2009-10-034-7/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Use this_cpu_ptr and __this_cpu_ptr in locations where straight transformations are possible because per_cpu_ptr is used with either smp_processor_id() or raw_smp_processor_id(). cc: David Howells <dhowells@redhat.com> Acked-by: Tejun Heo <tj@kernel.org> cc: Ingo Molnar <mingo@elte.hu> cc: Rusty Russell <rusty@rustcorp.com.au> cc: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: Christoph Lameter <cl@linux-foundation.org> Signed-off-by: Tejun Heo <tj@kernel.org>
* | this_cpu: Use this_cpu ops for network statisticsChristoph Lameter2009-10-032-8/+3
| | | | | | | | | | | | | | Acked-by: Tejun Heo <tj@kernel.org> Acked-by: David Miller <davem@davemloft.net> Signed-off-by: Christoph Lameter <cl@linux-foundation.org> Signed-off-by: Tejun Heo <tj@kernel.org>
* | this_cpu: Use this_cpu operations for NFS statisticsChristoph Lameter2009-10-031-21/+3
| | | | | | | | | | | | | | | | | | | | Simplify NFS statistics and allow the use of optimized arch instructions. Acked-by: Tejun Heo <tj@kernel.org> CC: Trond Myklebust <trond.myklebust@fys.uio.no> Signed-off-by: Christoph Lameter <cl@linux-foundation.org> Signed-off-by: Tejun Heo <tj@kernel.org>
* | this_cpu: Use this_cpu operations for SNMP statisticsChristoph Lameter2009-10-031-32/+18
| | | | | | | | | | | | | | | | | | | | SNMP statistic macros can be signficantly simplified. This will also reduce code size if the arch supports these operations in hardware. Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Christoph Lameter <cl@linux-foundation.org> Signed-off-by: Tejun Heo <tj@kernel.org>
* | this_cpu: Implement X86 optimized this_cpu operationsChristoph Lameter2009-10-031-0/+78
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Basically the existing percpu ops can be used for this_cpu variants that allow operations also on dynamically allocated percpu data. However, we do not pass a reference to a percpu variable in. Instead a dynamically or statically allocated percpu variable is provided. Preempt, the non preempt and the irqsafe operations generate the same code. It will always be possible to have the requires per cpu atomicness in a single RMW instruction with segment override on x86. 64 bit this_cpu operations are not supported on 32 bit. Signed-off-by: Christoph Lameter <cl@linux-foundation.org> Signed-off-by: Tejun Heo <tj@kernel.org>
* | this_cpu: Introduce this_cpu_ptr() and generic this_cpu_* operationsChristoph Lameter2009-10-032-0/+405
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch introduces two things: First this_cpu_ptr and then per cpu atomic operations. this_cpu_ptr ------------ A common operation when dealing with cpu data is to get the instance of the cpu data associated with the currently executing processor. This can be optimized by this_cpu_ptr(xx) = per_cpu_ptr(xx, smp_processor_id). The problem with per_cpu_ptr(x, smp_processor_id) is that it requires an array lookup to find the offset for the cpu. Processors typically have the offset for the current cpu area in some kind of (arch dependent) efficiently accessible register or memory location. We can use that instead of doing the array lookup to speed up the determination of the address of the percpu variable. This is particularly significant because these lookups occur in performance critical paths of the core kernel. this_cpu_ptr() can avoid memory accesses and this_cpu_ptr comes in two flavors. The preemption context matters since we are referring the the currently executing processor. In many cases we must insure that the processor does not change while a code segment is executed. __this_cpu_ptr -> Do not check for preemption context this_cpu_ptr -> Check preemption context The parameter to these operations is a per cpu pointer. This can be the address of a statically defined per cpu variable (&per_cpu_var(xxx)) or the address of a per cpu variable allocated with the per cpu allocator. per cpu atomic operations: this_cpu_*(var, val) ----------------------------------------------- this_cpu_* operations (like this_cpu_add(struct->y, value) operate on abitrary scalars that are members of structures allocated with the new per cpu allocator. They can also operate on static per_cpu variables if they are passed to per_cpu_var() (See patch to use this_cpu_* operations for vm statistics). These operations are guaranteed to be atomic vs preemption when modifying the scalar. The calculation of the per cpu offset is also guaranteed to be atomic at the same time. This means that a this_cpu_* operation can be safely used to modify a per cpu variable in a context where interrupts are enabled and preemption is allowed. Many architectures can perform such a per cpu atomic operation with a single instruction. Note that the atomicity here is different from regular atomic operations. Atomicity is only guaranteed for data accessed from the currently executing processor. Modifications from other processors are still possible. There must be other guarantees that the per cpu data is not modified from another processor when using these instruction. The per cpu atomicity is created by the fact that the processor either executes and instruction or not. Embedded in the instruction is the relocation of the per cpu address to the are reserved for the current processor and the RMW action. Therefore interrupts or preemption cannot occur in the mids of this processing. Generic fallback functions are used if an arch does not define optimized this_cpu operations. The functions come also come in the two flavors used for this_cpu_ptr(). The firstparameter is a scalar that is a member of a structure allocated through allocpercpu or a per cpu variable (use per_cpu_var(xxx)). The operations are similar to what percpu_add() and friends do. this_cpu_read(scalar) this_cpu_write(scalar, value) this_cpu_add(scale, value) this_cpu_sub(scalar, value) this_cpu_inc(scalar) this_cpu_dec(scalar) this_cpu_and(scalar, value) this_cpu_or(scalar, value) this_cpu_xor(scalar, value) Arch code can override the generic functions and provide optimized atomic per cpu operations. These atomic operations must provide both the relocation (x86 does it through a segment override) and the operation on the data in a single instruction. Otherwise preempt needs to be disabled and there is no gain from providing arch implementations. A third variant is provided prefixed by irqsafe_. These variants are safe against hardware interrupts on the *same* processor (all per cpu atomic primitives are *always* *only* providing safety for code running on the *same* processor!). The increment needs to be implemented by the hardware in such a way that it is a single RMW instruction that is either processed before or after an interrupt. cc: David Howells <dhowells@redhat.com> cc: Ingo Molnar <mingo@elte.hu> cc: Rusty Russell <rusty@rustcorp.com.au> cc: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: Christoph Lameter <cl@linux-foundation.org> Signed-off-by: Tejun Heo <tj@kernel.org>
* | percpu: kill legacy percpu allocatorTejun Heo2009-10-025-357/+0
| | | | | | | | | | | | | | | | | | | | With ia64 converted, there's no arch left which still uses legacy percpu allocator. Kill it. Signed-off-by: Tejun Heo <tj@kernel.org> Delightedly-acked-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Ingo Molnar <mingo@redhat.com> Cc: Christoph Lameter <cl@linux-foundation.org>
* | ia64: convert to dynamic percpu allocatorTejun Heo2009-10-024-20/+138
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Unlike other archs, ia64 reserves space for percpu areas during early memory initialization. These areas occupy a contiguous region indexed by cpu number on contiguous memory model or are grouped by node on discontiguous memory model. As allocation and initialization are done by the arch code, all that setup_per_cpu_areas() needs to do is communicating the determined layout to the percpu allocator. This patch implements setup_per_cpu_areas() for both contig and discontig memory models and drops HAVE_LEGACY_PER_CPU_AREA. Please note that for contig model, the allocation itself is modified only to allocate for possible cpus instead of NR_CPUS. As dynamic percpu allocator can handle non-direct mapping, there's no reason to allocate memory for cpus which aren't possible. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Tony Luck <tony.luck@intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: linux-ia64 <linux-ia64@vger.kernel.org>
* | ia64: allocate percpu area for cpu0 like percpu areas for other cpusTejun Heo2009-10-023-30/+57
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | cpu0 used special percpu area reserved by the linker, __cpu0_per_cpu, which is set up early in boot by head.S. However, this doesn't guarantee that the area will be on the same node as cpu0 and the percpu area for cpu0 ends up very far away from percpu areas for other cpus which cause problems for congruent percpu allocator. This patch makes percpu area initialization allocate percpu area for cpu0 like any other cpus and copy it from __cpu0_per_cpu which now resides in the __init area. This means that for cpu0, percpu area is first setup at __cpu0_per_cpu early by head.S and then moved to an area in the linear mapping during memory initialization and it's not allowed to take a pointer to percpu variables between head.S and memory initialization. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Tony Luck <tony.luck@intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: linux-ia64 <linux-ia64@vger.kernel.org>
* | ia64: initialize cpu maps earlyTejun Heo2009-10-022-24/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | All information necessary to initialize cpu possible and present maps are available once early_acpi_boot_init() is complete. Reorganize setup_arch() and acpi init functions such that, * CPU information is printed after LAPIC entries are parsed in early_acpi_boot_init(). * smp_build_cpu_map() is called by setup_arch() instead of acpi functions. * smp_build_cpu_map() is called once all CPU related information is available before memory is initialized. This is primarily to allow find_memory() to use cpu maps but is also a general cleanup. Please note that with this change, the somewhat ad-hoc early_cpu_possible_map defined and used for NUMA configurations is probably unnecessary. Something to clean up another day. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Tony Luck <tony.luck@intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: linux-ia64 <linux-ia64@vger.kernel.org>
* | ia64: don't alias VMALLOC_END to vmalloc_endTejun Heo2009-10-025-9/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If CONFIG_VIRTUAL_MEM_MAP is enabled, ia64 defines macro VMALLOC_END as unsigned long variable vmalloc_end which is adjusted to prepare room for vmemmap. This becomes probnlematic if a local variables vmalloc_end is defined in some function (not very unlikely) and VMALLOC_END is used in the function - the function thinks its referencing the global VMALLOC_END value but would be referencing its own local vmalloc_end variable. There's no reason VMALLOC_END should be a macro. Just define it as an unsigned long variable if CONFIG_VIRTUAL_MEM_MAP is set to avoid nasty surprises. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Tony Luck <tony.luck@intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: linux-ia64 <linux-ia64@vger.kernel.org> Cc: Christoph Lameter <cl@linux-foundation.org>
* | Merge branch 'for-linus' of ↵Linus Torvalds2009-10-0116-245/+745
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable: Btrfs: fix data space leak fix Btrfs: remove duplicates of filemap_ helpers Btrfs: take i_mutex before generic_write_checks Btrfs: fix arguments to btrfs_wait_on_page_writeback_range Btrfs: fix deadlock with free space handling and user transactions Btrfs: fix error cases for ioctl transactions Btrfs: Use CONFIG_BTRFS_POSIX_ACL to enable ACL code Btrfs: introduce missing kfree Btrfs: Fix setting umask when POSIX ACLs are not enabled Btrfs: proper -ENOSPC handling
| * \ Merge branch 'master' of ↵Chris Mason2009-10-011-0/+11
| |\ \ | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable into for-linus
| | * | Btrfs: fix data space leak fixJosef Bacik2009-10-011-0/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There is a problem where page_mkwrite can be called on a dirtied page that already has a delalloc range associated with it. The fix is to clear any delalloc bits for the range we are dirtying so the space accounting gets handled properly. This is the same thing we do in the normal write case, so we are consistent across the board. With this patch we no longer leak reserved space. Signed-off-by: Josef Bacik <jbacik@redhat.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
| * | | Btrfs: remove duplicates of filemap_ helpersChristoph Hellwig2009-10-014-102/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Use filemap_fdatawrite_range and filemap_fdatawait_range instead of local copies of the functions. For filemap_fdatawait_range that also means replacing the awkward old wait_on_page_writeback_range calling convention with the regular filemap byte offsets. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Chris Mason <chris.mason@oracle.com>
| * | | Merge branch 'master' of ↵Chris Mason2009-10-0114-146/+727
| |\ \ \ | | |/ / | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable into for-linus
| | * | Btrfs: take i_mutex before generic_write_checksChris Mason2009-10-011-8/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | btrfs_file_write was incorrectly calling generic_write_checks without taking i_mutex. This lead to problems with racing around i_size when doing O_APPEND writes. The fix here is to move i_mutex higher. Signed-off-by: Chris Mason <chris.mason@oracle.com>
| | * | Btrfs: fix arguments to btrfs_wait_on_page_writeback_rangeChristoph Hellwig2009-10-011-1/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | wait_on_page_writeback_range/btrfs_wait_on_page_writeback_range takes a pagecache offset, not a byte offset into the file. Shift the arguments around to wait for the correct range Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Chris Mason <chris.mason@oracle.com>
| | * | Btrfs: fix deadlock with free space handling and user transactionsSage Weil2009-09-291-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If an ioctl-initiated transaction is open, we can't force a commit during the free space checks in order to free up pinned extents or else we deadlock. Just ENOSPC instead. A more satisfying solution that reserves space for the entire user transaction up front is forthcoming... Signed-off-by: Sage Weil <sage@newdream.net> Signed-off-by: Chris Mason <chris.mason@oracle.com>
| | * | Btrfs: fix error cases for ioctl transactionsSage Weil2009-09-291-19/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix leak of vfsmount write reference and open_ioctl_trans reference on ENOMEM. Clean up the error paths while we're at it. Signed-off-by: Sage Weil <sage@newdream.net> Signed-off-by: Chris Mason <chris.mason@oracle.com>
| | * | Btrfs: Use CONFIG_BTRFS_POSIX_ACL to enable ACL codeChris Ball2009-09-293-5/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We've already defined CONFIG_BTRFS_POSIX_ACL in Kconfig, but we're currently not using it and are testing CONFIG_FS_POSIX_ACL instead. CONFIG_FS_POSIX_ACL states "Never use this symbol for ifdefs". Signed-off-by: Chris Ball <cjb@laptop.org> Signed-off-by: Chris Mason <chris.mason@oracle.com>
| | * | Btrfs: introduce missing kfreeJulia Lawall2009-09-291-1/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Error handling code following a kzalloc should free the allocated data. The semantic match that finds the problem is as follows: (http://www.emn.fr/x-info/coccinelle/) // <smpl> @r exists@ local idexpression x; statement S; expression E; identifier f,f1,l; position p1,p2; expression *ptr != NULL; @@ x@p1 = \(kmalloc\|kzalloc\|kcalloc\)(...); ... if (x == NULL) S <... when != x when != if (...) { <+...x...+> } ( x->f1 = E | (x->f1 == NULL || ...) | f(...,x->f1,...) ) ...> ( return \(0\|<+...x...+>\|ptr\); | return@p2 ...; ) @script:python@ p1 << r.p1; p2 << r.p2; @@ print "* file: %s kmalloc %s return %s" % (p1[0].file,p1[0].line,p2[0].line) // </smpl> Signed-off-by: Julia Lawall <julia@diku.dk> Signed-off-by: Chris Mason <chris.mason@oracle.com>
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