linux/kernel/rcupdate.c, branch v2.6.23

Add suspend-related notifications for CPU hotplug

2007-05-09T19:30:56Z

Since nonboot CPUs are now disabled after tasks and devices have been frozen and the CPU hotplug infrastructure is used for this purpose, we need special CPU hotplug notifications that will help the CPU-hotplug-aware subsystems distinguish normal CPU hotplug events from CPU hotplug events related to a system-wide suspend or resume operation in progress. This patch introduces such notifications and causes them to be used during suspend and resume transitions. It also changes all of the CPU-hotplug-aware subsystems to take these notifications into consideration (for now they are handled in the same way as the corresponding "normal" ones). [oleg@tv-sign.ru: cleanups] Signed-off-by: Rafael J. Wysocki Cc: Gautham R Shenoy Cc: Pavel Machek Signed-off-by: Oleg Nesterov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] rcu: add a prefetch() in rcu_do_batch()

2006-12-07T16:39:40Z

On some workloads, (for example when lot of close() syscalls are done), RCU qlen can be quite large, and RCU heads are no longer in cpu cache when rcu_do_batch() is called. This patch adds a prefetch() in rcu_do_batch() to give CPU a hint to bring back cache lines containing 'struct rcu_head's. Most list manipulations macros include prefetch(), but not open coded ones (at least with current C compilers :) ) I got a nice speedup on a trivial benchmark (3.48 us per iteration instead of 3.95 us on a 1.6 GHz Pentium-M) while (1) { pipe(p); close(fd[0]); close(fd[1]);} Signed-off-by: Eric Dumazet Cc: "Paul E. McKenney" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] rcu: simplify/improve batch tuning

2006-10-04T14:55:31Z

Kill a hard-to-calculate 'rsinterval' boot parameter and per-cpu rcu_data.last_rs_qlen. Instead, it adds adds a flag rcu_ctrlblk.signaled, which records the fact that one of CPUs has sent a resched IPI since the last rcu_start_batch(). Roughly speaking, we need two rcu_start_batch()s in order to move callbacks from ->nxtlist to ->donelist. This means that when ->qlen exceeds qhimark and continues to grow, we should send a resched IPI, and then do it again after we gone through a quiescent state. On the other hand, if it was already sent, we don't need to do it again when another CPU detects overflow of the queue. Signed-off-by: Oleg Nesterov Acked-by: Paul E. McKenney Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] rcu_do_batch: make ->qlen decrement irq safe

2006-09-13T14:32:14Z

rcu_do_batch() decrements rdp->qlen with irqs enabled. This is not good, it can also be modified by call_rcu() from interrupt. Decrement ->qlen once with irqs disabled, after a main loop. Signed-off-by: Oleg Nesterov Cc: Dipankar Sarma Cc: "Paul E. McKenney" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] cpu hotplug: replace devinit* with cpuinit* for cpu notifications

2006-07-31T20:28:39Z

Few of the callback functions and notifier blocks that are associated with cpu notifications incorrectly have __devinit and __devinitdata. They should be __cpuinit and __cpuinitdata instead. It makes no functional difference but wastes text area when CONFIG_HOTPLUG is enabled and CONFIG_HOTPLUG_CPU is not. This patch fixes all those instances. Signed-off-by: Chandra Seetharaman Cc: Ashok Raj Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] lockdep: locking init debugging improvement

2006-07-03T22:27:02Z

Locking init improvement: - introduce and use __SPIN_LOCK_UNLOCKED for array initializations, to pass in the name string of locks, used by debugging Signed-off-by: Ingo Molnar Signed-off-by: Arjan van de Ven Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] cpu hotplug: revert initdata patch submitted for 2.6.17

2006-06-28T00:32:41Z

This patch reverts notifier_block changes made in 2.6.17 Signed-off-by: Chandra Seetharaman Cc: Ashok Raj Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] cpu hotplug: revert init patch submitted for 2.6.17

2006-06-28T00:32:40Z

In 2.6.17, there was a problem with cpu_notifiers and XFS. I provided a band-aid solution to solve that problem. In the process, i undid all the changes you both were making to ensure that these notifiers were available only at init time (unless CONFIG_HOTPLUG_CPU is defined). We deferred the real fix to 2.6.18. Here is a set of patches that fixes the XFS problem cleanly and makes the cpu notifiers available only at init time (unless CONFIG_HOTPLUG_CPU is defined). If CONFIG_HOTPLUG_CPU is defined then cpu notifiers are available at run time. This patch reverts the notifier_call changes made in 2.6.17 Signed-off-by: Chandra Seetharaman Cc: Ashok Raj Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] rcutorture: add call_rcu_bh() operations

2006-06-28T00:32:40Z

Add operations for the call_rcu_bh() variant of RCU. Also add an rcu_batches_completed_bh() function, which is needed by rcutorture. Signed-off-by: Paul E. McKenney Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

[PATCH] Make RCU API inaccessible to non-GPL Linux kernel modules

2006-06-23T14:43:07Z

Remove synchronize_kernel() (deprecated 2-APR-2005 in http://lkml.org/lkml/2005/4/3/11) and makes the RCU API inaccessible to non-GPL Linux kernel modules (as was announced more than one year ago in http://lkml.org/lkml/2005/4/3/8). Tested on x86 and ppc64. Signed-off-by: "Paul E. McKenney" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

linux/kernel/rcupdate.c, branch v2.6.23

Add suspend-related notifications for CPU hotplug

[PATCH] rcu: add a prefetch() in rcu_do_batch()

[PATCH] rcu: simplify/improve batch tuning

[PATCH] rcu_do_batch: make ->qlen decrement irq safe

[PATCH] cpu hotplug: replace __devinit* with __cpuinit* for cpu notifications

[PATCH] lockdep: locking init debugging improvement

[PATCH] cpu hotplug: revert initdata patch submitted for 2.6.17

[PATCH] cpu hotplug: revert init patch submitted for 2.6.17

[PATCH] rcutorture: add call_rcu_bh() operations

[PATCH] Make RCU API inaccessible to non-GPL Linux kernel modules

[PATCH] cpu hotplug: replace devinit* with cpuinit* for cpu notifications