kernel/net/rds/page.c, branch 0x221E-v0.0.1-v6.19

rds: Use nested-BH locking for rds_page_remainder

2025-05-15T13:23:31Z

rds_page_remainder is a per-CPU variable and relies on disabled BH for its locking. Without per-CPU locking in local_bh_disable() on PREEMPT_RT this data structure requires explicit locking. Add a local_lock_t to the data structure and use local_lock_nested_bh() for locking. This change adds only lockdep coverage and does not alter the functional behaviour for !PREEMPT_RT. Cc: Allison Henderson Cc: linux-rdma@vger.kernel.org Signed-off-by: Sebastian Andrzej Siewior Link: https://patch.msgid.link/20250512092736.229935-16-bigeasy@linutronix.de Signed-off-by: Paolo Abeni

rds: Acquire per-CPU pointer within BH disabled section

2025-05-15T13:23:31Z

rds_page_remainder_alloc() obtains the current CPU with get_cpu() while disabling preemption. Then the CPU number is used to access the per-CPU data structure via per_cpu(). This can be optimized by relying on local_bh_disable() to provide a stable CPU number/ avoid migration and then using this_cpu_ptr() to retrieve the data structure. Cc: Allison Henderson Cc: linux-rdma@vger.kernel.org Signed-off-by: Sebastian Andrzej Siewior Link: https://patch.msgid.link/20250512092736.229935-15-bigeasy@linutronix.de Signed-off-by: Paolo Abeni

rds: Disable only bottom halves in rds_page_remainder_alloc()

2025-05-15T13:23:31Z

rds_page_remainder_alloc() is invoked from a preemptible context or a tasklet. There is no need to disable interrupts for locking. Use local_bh_disable() instead of local_irq_save() for locking. Cc: Allison Henderson Cc: linux-rdma@vger.kernel.org Signed-off-by: Sebastian Andrzej Siewior Link: https://patch.msgid.link/20250512092736.229935-14-bigeasy@linutronix.de Signed-off-by: Paolo Abeni

rds: remove dead code

2016-12-27T02:35:39Z

Signed-off-by: Al Viro

RDS: memory allocated must be align to 8

2016-04-07T20:58:27Z

Fix issue in 'rds_ib_cong_recv' when accessing unaligned memory allocated by 'rds_page_remainder_alloc' using uint64_t pointer. Signed-off-by: Shamir Rabinovitch Signed-off-by: David S. Miller

tags: Fix DEFINE_PER_CPU expansions

2016-03-15T23:55:16Z

$ make tags GEN tags ctags: Warning: drivers/acpi/processor_idle.c:64: null expansion of name pattern "\1" ctags: Warning: drivers/xen/events/events_2l.c:41: null expansion of name pattern "\1" ctags: Warning: kernel/locking/lockdep.c:151: null expansion of name pattern "\1" ctags: Warning: kernel/rcu/rcutorture.c:133: null expansion of name pattern "\1" ctags: Warning: kernel/rcu/rcutorture.c:135: null expansion of name pattern "\1" ctags: Warning: kernel/workqueue.c:323: null expansion of name pattern "\1" ctags: Warning: net/ipv4/syncookies.c:53: null expansion of name pattern "\1" ctags: Warning: net/ipv6/syncookies.c:44: null expansion of name pattern "\1" ctags: Warning: net/rds/page.c:45: null expansion of name pattern "\1" Which are all the result of the DEFINE_PER_CPU pattern: scripts/tags.sh:200: '/\ Acked-by: David S. Miller Acked-by: Rafael J. Wysocki Cc: Tejun Heo Cc: "Paul E. McKenney" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

RDS: don't pretend to use cpu notifiers

2015-12-22T20:23:05Z

It looks like an attempt to use CPU notifier here which was never completed. Nobody tried to wire it up completely since 2k9. So I unwind this code and get rid of everything not required. Oh look! 19 lines were removed while code still does the same thing. Acked-by: Santosh Shilimkar Tested-by: Santosh Shilimkar Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: David S. Miller

net: Fix (nearly-)kernel-doc comments for various functions

2012-07-11T06:13:45Z

Fix incorrect start markers, wrapped summary lines, missing section breaks, incorrect separators, and some name mismatches. Signed-off-by: Ben Hutchings Signed-off-by: David S. Miller

net: Add export.h for EXPORT_SYMBOL/THIS_MODULE to non-modules

2011-10-31T23:30:30Z

These files are non modular, but need to export symbols using the macros now living in export.h -- call out the include so that things won't break when we remove the implicit presence of module.h from everywhere. Signed-off-by: Paul Gortmaker

notifiers: cpu: move cpu notifiers into cpu.h

2011-07-26T03:57:14Z

We presently define all kinds of notifiers in notifier.h. This is not necessary at all, since different subsystems use different notifiers, they are almost non-related with each other. This can also save much build time. Suppose I add a new netdevice event, really I don't have to recompile all the source, just network related. Without this patch, all the source will be recompiled. I move the notify events near to their subsystem notifier registers, so that they can be found more easily. This patch: It is not necessary to share the same notifier.h. Signed-off-by: WANG Cong Cc: David Miller Cc: "Rafael J. Wysocki" Cc: Greg KH Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds