Commit 3459f0d7 authored by Ingo Molnar's avatar Ingo Molnar
Browse files

Merge branch 'linus' into perf/urgent, to pick up the upstream merged bits 



Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
parents 9fc81d87 bee2782f

Documentation/ABI/stable/sysfs-driver-ib_srp

+19 −6
Original line number Original line Diff line number Diff line
@@ -55,12 +55,12 @@ Description: Interface for making ib_srp connect to a new target. 
		  only safe with partial memory descriptor list support enabled

		  only safe with partial memory descriptor list support enabled

		  (allow_ext_sg=1).

		  (allow_ext_sg=1).

		* comp_vector, a number in the range 0..n-1 specifying the

		* comp_vector, a number in the range 0..n-1 specifying the

		  MSI-X completion vector. Some HCA's allocate multiple (n)

		  MSI-X completion vector of the first RDMA channel. Some

		  MSI-X vectors per HCA port. If the IRQ affinity masks of

		  HCA's allocate multiple (n) MSI-X vectors per HCA port. If

		  these interrupts have been configured such that each MSI-X

		  the IRQ affinity masks of these interrupts have been

		  interrupt is handled by a different CPU then the comp_vector

		  configured such that each MSI-X interrupt is handled by a

		  parameter can be used to spread the SRP completion workload

		  different CPU then the comp_vector parameter can be used to

		  over multiple CPU's.

		  spread the SRP completion workload over multiple CPU's.

		* tl_retry_count, a number in the range 2..7 specifying the

		* tl_retry_count, a number in the range 2..7 specifying the

		  IB RC retry count.

		  IB RC retry count.

		* queue_size, the maximum number of commands that the

		* queue_size, the maximum number of commands that the
@@ -88,6 +88,13 @@ Description: Whether ib_srp is allowed to include a partial memory 
		descriptor list in an SRP_CMD when communicating with an SRP

		descriptor list in an SRP_CMD when communicating with an SRP

		target.

		target.





What:		/sys/class/scsi_host/host<n>/ch_count

Date:		April 1, 2015

KernelVersion:	3.19

Contact:	linux-rdma@vger.kernel.org

Description:	Number of RDMA channels used for communication with the SRP

		target.



What:		/sys/class/scsi_host/host<n>/cmd_sg_entries

What:		/sys/class/scsi_host/host<n>/cmd_sg_entries

Date:		May 19, 2011

Date:		May 19, 2011

KernelVersion:	2.6.39

KernelVersion:	2.6.39
@@ -95,6 +102,12 @@ Contact: linux-rdma@vger.kernel.org 
Description:	Maximum number of data buffer descriptors that may be sent to

Description:	Maximum number of data buffer descriptors that may be sent to

		the target in a single SRP_CMD request.

		the target in a single SRP_CMD request.





What:		/sys/class/scsi_host/host<n>/comp_vector

Date:		September 2, 2013

KernelVersion:	3.11

Contact:	linux-rdma@vger.kernel.org

Description:	Completion vector used for the first RDMA channel.



What:		/sys/class/scsi_host/host<n>/dgid

What:		/sys/class/scsi_host/host<n>/dgid

Date:		June 17, 2006

Date:		June 17, 2006

KernelVersion:	2.6.17

KernelVersion:	2.6.17

Documentation/RCU/rcu.txt

+2 −2
Original line number Original line Diff line number Diff line
@@ -36,7 +36,7 @@ o How can the updater tell when a grace period has completed 
	executed in user mode, or executed in the idle loop, we can

	executed in user mode, or executed in the idle loop, we can

	safely free up that item.

	safely free up that item.





	Preemptible variants of RCU (CONFIG_TREE_PREEMPT_RCU) get the

	Preemptible variants of RCU (CONFIG_PREEMPT_RCU) get the

	same effect, but require that the readers manipulate CPU-local

	same effect, but require that the readers manipulate CPU-local

	counters.  These counters allow limited types of blocking within

	counters.  These counters allow limited types of blocking within

	RCU read-side critical sections.  SRCU also uses CPU-local

	RCU read-side critical sections.  SRCU also uses CPU-local
@@ -81,7 +81,7 @@ o I hear that RCU is patented? What is with that? 
o	I hear that RCU needs work in order to support realtime kernels?

o	I hear that RCU needs work in order to support realtime kernels?





	This work is largely completed.  Realtime-friendly RCU can be

	This work is largely completed.  Realtime-friendly RCU can be

	enabled via the CONFIG_TREE_PREEMPT_RCU kernel configuration

	enabled via the CONFIG_PREEMPT_RCU kernel configuration

	parameter.  However, work is in progress for enabling priority

	parameter.  However, work is in progress for enabling priority

	boosting of preempted RCU read-side critical sections.	This is

	boosting of preempted RCU read-side critical sections.	This is

	needed if you have CPU-bound realtime threads.

	needed if you have CPU-bound realtime threads.

Documentation/RCU/stallwarn.txt

+4 −10
Original line number Original line Diff line number Diff line
@@ -26,12 +26,6 @@ CONFIG_RCU_CPU_STALL_TIMEOUT 
	Stall-warning messages may be enabled and disabled completely via

	Stall-warning messages may be enabled and disabled completely via

	/sys/module/rcupdate/parameters/rcu_cpu_stall_suppress.

	/sys/module/rcupdate/parameters/rcu_cpu_stall_suppress.





CONFIG_RCU_CPU_STALL_VERBOSE



	This kernel configuration parameter causes the stall warning to

	also dump the stacks of any tasks that are blocking the current

	RCU-preempt grace period.



CONFIG_RCU_CPU_STALL_INFO

CONFIG_RCU_CPU_STALL_INFO





	This kernel configuration parameter causes the stall warning to

	This kernel configuration parameter causes the stall warning to
@@ -77,7 +71,7 @@ This message indicates that CPU 5 detected that it was causing a stall, 
and that the stall was affecting RCU-sched.  This message will normally be

and that the stall was affecting RCU-sched.  This message will normally be

followed by a stack dump of the offending CPU.  On TREE_RCU kernel builds,

followed by a stack dump of the offending CPU.  On TREE_RCU kernel builds,

RCU and RCU-sched are implemented by the same underlying mechanism,

RCU and RCU-sched are implemented by the same underlying mechanism,

while on TREE_PREEMPT_RCU kernel builds, RCU is instead implemented

while on PREEMPT_RCU kernel builds, RCU is instead implemented

by rcu_preempt_state.

by rcu_preempt_state.





On the other hand, if the offending CPU fails to print out a stall-warning

On the other hand, if the offending CPU fails to print out a stall-warning
@@ -89,7 +83,7 @@ INFO: rcu_bh_state detected stalls on CPUs/tasks: { 3 5 } (detected by 2, 2502 j 
This message indicates that CPU 2 detected that CPUs 3 and 5 were both

This message indicates that CPU 2 detected that CPUs 3 and 5 were both

causing stalls, and that the stall was affecting RCU-bh.  This message

causing stalls, and that the stall was affecting RCU-bh.  This message

will normally be followed by stack dumps for each CPU.  Please note that

will normally be followed by stack dumps for each CPU.  Please note that

TREE_PREEMPT_RCU builds can be stalled by tasks as well as by CPUs,

PREEMPT_RCU builds can be stalled by tasks as well as by CPUs,

and that the tasks will be indicated by PID, for example, "P3421".

and that the tasks will be indicated by PID, for example, "P3421".

It is even possible for a rcu_preempt_state stall to be caused by both

It is even possible for a rcu_preempt_state stall to be caused by both

CPUs -and- tasks, in which case the offending CPUs and tasks will all

CPUs -and- tasks, in which case the offending CPUs and tasks will all
@@ -205,10 +199,10 @@ o A CPU-bound real-time task in a CONFIG_PREEMPT kernel, which might 
o	A CPU-bound real-time task in a CONFIG_PREEMPT_RT kernel that

o	A CPU-bound real-time task in a CONFIG_PREEMPT_RT kernel that

	is running at a higher priority than the RCU softirq threads.

	is running at a higher priority than the RCU softirq threads.

	This will prevent RCU callbacks from ever being invoked,

	This will prevent RCU callbacks from ever being invoked,

	and in a CONFIG_TREE_PREEMPT_RCU kernel will further prevent

	and in a CONFIG_PREEMPT_RCU kernel will further prevent

	RCU grace periods from ever completing.  Either way, the

	RCU grace periods from ever completing.  Either way, the

	system will eventually run out of memory and hang.  In the

	system will eventually run out of memory and hang.  In the

	CONFIG_TREE_PREEMPT_RCU case, you might see stall-warning

	CONFIG_PREEMPT_RCU case, you might see stall-warning

	messages.

	messages.





o	A hardware or software issue shuts off the scheduler-clock

o	A hardware or software issue shuts off the scheduler-clock

Documentation/RCU/trace.txt

+2 −2
Original line number Original line Diff line number Diff line
@@ -8,7 +8,7 @@ The following sections describe the debugfs files and formats, first 
for rcutree and next for rcutiny.

for rcutree and next for rcutiny.









CONFIG_TREE_RCU and CONFIG_TREE_PREEMPT_RCU debugfs Files and Formats

CONFIG_TREE_RCU and CONFIG_PREEMPT_RCU debugfs Files and Formats





These implementations of RCU provide several debugfs directories under the

These implementations of RCU provide several debugfs directories under the

top-level directory "rcu":

top-level directory "rcu":
@@ -18,7 +18,7 @@ rcu/rcu_preempt 
rcu/rcu_sched

rcu/rcu_sched





Each directory contains files for the corresponding flavor of RCU.

Each directory contains files for the corresponding flavor of RCU.

Note that rcu/rcu_preempt is only present for CONFIG_TREE_PREEMPT_RCU.

Note that rcu/rcu_preempt is only present for CONFIG_PREEMPT_RCU.

For CONFIG_TREE_RCU, the RCU flavor maps onto the RCU-sched flavor,

For CONFIG_TREE_RCU, the RCU flavor maps onto the RCU-sched flavor,

so that activity for both appears in rcu/rcu_sched.

so that activity for both appears in rcu/rcu_sched.

Documentation/RCU/whatisRCU.txt

+1 −1
Original line number Original line Diff line number Diff line
@@ -137,7 +137,7 @@ rcu_read_lock() 
	Used by a reader to inform the reclaimer that the reader is

	Used by a reader to inform the reclaimer that the reader is

	entering an RCU read-side critical section.  It is illegal

	entering an RCU read-side critical section.  It is illegal

	to block while in an RCU read-side critical section, though

	to block while in an RCU read-side critical section, though

	kernels built with CONFIG_TREE_PREEMPT_RCU can preempt RCU

	kernels built with CONFIG_PREEMPT_RCU can preempt RCU

	read-side critical sections.  Any RCU-protected data structure

	read-side critical sections.  Any RCU-protected data structure

	accessed during an RCU read-side critical section is guaranteed to

	accessed during an RCU read-side critical section is guaranteed to

	remain unreclaimed for the full duration of that critical section.

	remain unreclaimed for the full duration of that critical section.