kernel/linux.git/include/linux/srcu.h, branch v5.0.15

srcu: Use "ssp" instead of "sp" for srcu_struct pointer

2018-11-27T17:24:17+00:00

In RCU, the distinction between "rsp", "rnp", and "rdp" has served well for a great many years, but in SRCU, "sp" vs. "sdp" has proven confusing. This commit therefore renames SRCU's "sp" pointers to "ssp", so that there is "ssp" for srcu_struct pointer, "snp" for srcu_node pointer, and "sdp" for srcu_data pointer. Signed-off-by: Paul E. McKenney

srcu: Fix kernel-doc missing notation

2018-11-09T05:54:14+00:00

Fix kernel-doc warnings for missing parameter descriptions: ../include/linux/srcu.h:175: warning: Function parameter or member 'p' not described in 'srcu_dereference_notrace' ../include/linux/srcu.h:175: warning: Function parameter or member 'sp' not described in 'srcu_dereference_notrace' Fixes: 0b764a6e4e19d ("srcu: Add notrace variant of srcu_dereference") Signed-off-by: Randy Dunlap Cc: Lai Jiangshan Cc: "Paul E. McKenney" Cc: Josh Triplett Cc: Steven Rostedt Cc: Mathieu Desnoyers Cc: Joel Fernandes (Google) Signed-off-by: Paul E. McKenney

srcu: Add notrace variant of srcu_dereference

2018-07-26T14:50:16+00:00

In the last patch in this series, we are making lockdep register hooks onto the irq_{disable,enable} tracepoints. These tracepoints use the _rcuidle tracepoint variant. In this series we switch the _rcuidle tracepoint callers to use SRCU instead of sched-RCU. Inorder to dereference the pointer to the probe functions, we could call srcu_dereference, however this API will call back into lockdep to check if the lock is held *before* the lockdep probe hooks have a chance to run and annotate the IRQ enabled/disabled state. For this reason we need a notrace variant of srcu_dereference since otherwise we get lockdep splats. This patch adds the needed srcu_dereference_notrace variant. Link: http://lkml.kernel.org/r/20180628182149.226164-3-joel@joelfernandes.org Reviewed-by: Paul E. McKenney Signed-off-by: Joel Fernandes (Google) Signed-off-by: Steven Rostedt (VMware)

srcu: Add notrace variants of srcu_read_{lock,unlock}

2018-07-26T14:50:16+00:00

This is needed for a future tracepoint patch that uses srcu, and to make sure it doesn't call into lockdep. tracepoint code already calls notrace variants for rcu_read_lock_sched so this patch does the same for srcu which will be used in a later patch. Keeps it consistent with rcu-sched. [Joel: Added commit message] Link: http://lkml.kernel.org/r/20180628182149.226164-2-joel@joelfernandes.org Reviewed-by: Steven Rostedt (VMware) Signed-off-by: Paul McKenney Signed-off-by: Joel Fernandes (Google) Signed-off-by: Steven Rostedt (VMware)

srcu: Add cleanup_srcu_struct_quiesced()

2018-05-15T17:27:56+00:00

The current cleanup_srcu_struct() flushes work, which prevents it from being invoked from some workqueue contexts, as well as from atomic (non-blocking) contexts. This patch therefore introduced a cleanup_srcu_struct_quiesced(), which can be invoked only after all activity on the specified srcu_struct has completed. This restriction allows cleanup_srcu_struct_quiesced() to be invoked from workqueue contexts as well as from atomic contexts. Suggested-by: Christoph Hellwig Signed-off-by: Paul E. McKenney Tested-by: Nitzan Carmi Tested-by: Nicholas Piggin

lockdep: Convert some users to const

2018-01-18T10:56:49+00:00

These users of lockdep_is_held() either wanted lockdep_is_held to take a const pointer, or would benefit from providing a const pointer. Signed-off-by: Matthew Wilcox Signed-off-by: Thomas Gleixner Acked-by: Peter Zijlstra (Intel) Cc: "David S. Miller" Link: https://lkml.kernel.org/r/20180117151414.23686-4-willy@infradead.org

doc: Fix various RCU docbook comment-header problems

2017-10-20T02:26:11+00:00

Because many of RCU's files have not been included into docbook, a number of errors have accumulated. This commit fixes them. Signed-off-by: Paul E. McKenney Signed-off-by: Linus Torvalds

srcu: Remove Classic SRCU

2017-06-09T01:52:42+00:00

Classic SRCU was only ever intended to be a fallback in case of issues with Tree/Tiny SRCU, and the latter two are doing quite well in testing. This commit therefore removes Classic SRCU. Signed-off-by: Paul E. McKenney

srcu: Shrink srcu.h by moving docbook and private function

2017-06-09T01:52:35+00:00

The call_srcu() docbook entry is currently in include/linux/srcu.h, which causes needless processing for each include point. This commit therefore moves this entry to kernel/rcu/srcutree.c, which the compiler reads only once. In addition, the srcu_batches_completed() function is used only within RCU and its torture-test suites. This commit therefore also moves this function's declaration from include/linux/srcutiny.h, include/linux/srcutree.h, and include/linux/srcuclassic.h to kernel/rcu/rcu.h. Signed-off-by: Paul E. McKenney

srcu: Make SRCU be once again optional

2017-06-08T15:25:38+00:00

Commit d160a727c40e ("srcu: Make SRCU be built by default") in response to build errors, which were caused by code that included srcu.h despite !SRCU. However, srcutiny.o is almost 2K of code, which is not insignificant for those attempting to run the Linux kernel on IoT devices. This commit therefore makes SRCU be once again optional, and adjusts srcu.h to allow error-free inclusion in !SRCU kernel builds. Signed-off-by: Paul E. McKenney Acked-by: Nicolas Pitre