aboutsummaryrefslogtreecommitdiff
path: root/kernel/rcutree.h
AgeCommit message (Collapse)Author
2009-08-29rcu: Changes from reviews: avoid casts, fix/add warnings, improve commentsPaul E. McKenney
Changes suggested by review comments from Josh Triplett and Mathieu Desnoyers. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Acked-by: Josh Triplett <josh@joshtriplett.org> Acked-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> Cc: laijs@cn.fujitsu.com Cc: dipankar@in.ibm.com Cc: akpm@linux-foundation.org Cc: dvhltc@us.ibm.com Cc: niv@us.ibm.com Cc: peterz@infradead.org Cc: rostedt@goodmis.org LKML-Reference: <20090827220012.GA30525@linux.vnet.ibm.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-23rcu: Merge preemptable-RCU functionality into hierarchical RCUPaul E. McKenney
Create a kernel/rcutree_plugin.h file that contains definitions for preemptable RCU (or, under the #else branch of the #ifdef, empty definitions for the classic non-preemptable semantics). These definitions fit into plugins defined in kernel/rcutree.c for this purpose. This variant of preemptable RCU uses a new algorithm whose read-side expense is roughly that of classic hierarchical RCU under CONFIG_PREEMPT. This new algorithm's update-side expense is similar to that of classic hierarchical RCU, and, in absence of read-side preemption or blocking, is exactly that of classic hierarchical RCU. Perhaps more important, this new algorithm has a much simpler implementation, saving well over 1,000 lines of code compared to mainline's implementation of preemptable RCU, which will hopefully be retired in favor of this new algorithm. The simplifications are obtained by maintaining per-task nesting state for running tasks, and using a simple lock-protected algorithm to handle accounting when tasks block within RCU read-side critical sections, making use of lessons learned while creating numerous user-level RCU implementations over the past 18 months. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: laijs@cn.fujitsu.com Cc: dipankar@in.ibm.com Cc: akpm@linux-foundation.org Cc: mathieu.desnoyers@polymtl.ca Cc: josht@linux.vnet.ibm.com Cc: dvhltc@us.ibm.com Cc: niv@us.ibm.com Cc: peterz@infradead.org Cc: rostedt@goodmis.org LKML-Reference: <12509746134003-git-send-email-> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-23rcu: Renamings to increase RCU clarityPaul E. McKenney
Make RCU-sched, RCU-bh, and RCU-preempt be underlying implementations, with "RCU" defined in terms of one of the three. Update the outdated rcu_qsctr_inc() names, as these functions no longer increment anything. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: laijs@cn.fujitsu.com Cc: dipankar@in.ibm.com Cc: akpm@linux-foundation.org Cc: mathieu.desnoyers@polymtl.ca Cc: josht@linux.vnet.ibm.com Cc: dvhltc@us.ibm.com Cc: niv@us.ibm.com Cc: peterz@infradead.org Cc: rostedt@goodmis.org LKML-Reference: <12509746132696-git-send-email-> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-08-23rcu: Move private definitions from include/linux/rcutree.h to kernel/rcutree.hPaul E. McKenney
Some information hiding that makes it easier to merge preemptability into rcutree without descending into #include hell. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: laijs@cn.fujitsu.com Cc: dipankar@in.ibm.com Cc: akpm@linux-foundation.org Cc: mathieu.desnoyers@polymtl.ca Cc: josht@linux.vnet.ibm.com Cc: dvhltc@us.ibm.com Cc: niv@us.ibm.com Cc: peterz@infradead.org Cc: rostedt@goodmis.org LKML-Reference: <1250974613373-git-send-email-> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-04-03kmemtrace, rcu: fix rcu_tree_trace.c data structure dependenciesIngo Molnar
Impact: cleanup We want to remove rcutree internals from the public rcutree.h file for upcoming kmemtrace changes - but kernel/rcutree_trace.c depends on them. Introduce kernel/rcutree.h for internal definitions. (Probably all the other data types from include/linux/rcutree.h could be moved here too - except rcu_data.) Cc: Pekka Enberg <penberg@cs.helsinki.fi> Cc: Eduard - Gabriel Munteanu <eduard.munteanu@linux360.ro> Cc: paulmck@linux.vnet.ibm.com LKML-Reference: <1237898630.25315.83.camel@penberg-laptop> Signed-off-by: Ingo Molnar <mingo@elte.hu>