48e9a6c1f54695609b709bf674aac133794ada00 |
|
24-Sep-2014 |
Martin Schwidefsky <schwidefsky@de.ibm.com> |
s390/topology: call set_sched_topology early The call to topology_init is too late for the set_sched_topology call. The initial scheduling domain structure has already been established with default topology array. Use the smp_cpus_done() call to get the s390 specific topology array registered early enough. Cc: stable@vger.kernel.org # v3.16+ Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
|
50be634507284eea38df78154d22615d21200b42 |
|
29-Jan-2014 |
Philipp Hachtmann <phacht@linux.vnet.ibm.com> |
s390/mm: Convert bootmem to memblock The original bootmem allocator is getting replaced by memblock. To cover the needs of the s390 kdump implementation the physical memory list is used. With this patch the bootmem allocator and its bitmaps are completely removed from s390. Signed-off-by: Philipp Hachtmann <phacht@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
|
2dfd747629e65f89d2dbceb92fffc763f66228b2 |
|
11-Apr-2014 |
Vincent Guittot <vincent.guittot@linaro.org> |
sched, s390: Create a dedicated topology table BOOK level is only relevant for s390 so we create a dedicated topology table with BOOK level and remove it from default table. Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Philipp Hachtmann <phacht@linux.vnet.ibm.com> Cc: cmetcalf@tilera.com Cc: benh@kernel.crashing.org Cc: dietmar.eggemann@arm.com Cc: preeti@linux.vnet.ibm.com Cc: tony.luck@intel.com Cc: fenghua.yu@intel.com Cc: linux390@de.ibm.com Cc: linux-s390@vger.kernel.org Link: http://lkml.kernel.org/r/1397209481-28542-3-git-send-email-vincent.guittot@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
|
43eab381181c76a19734298b5c925c45fb1afe45 |
|
26-Feb-2014 |
Philipp Hachtmann <phacht@linux.vnet.ibm.com> |
s390/topology: Remove call to update_cpu_masks() The call to update_cpu_masks() from within topology_init() is completely redundant. This patch removes it. Signed-off-by: Philipp Hachtmann <phacht@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
|
80020fbd65c17d3d9e7d80cfd3fa4c57ae7ff765 |
|
07-Jan-2013 |
Heiko Carstens <heiko.carstens@de.ibm.com> |
s390/topology: export cpu_topology Export cpu_topology symbol, so it's available for modules. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
|
d1e57508fbd63b340788afe6f2c74a608603e714 |
|
12-Nov-2012 |
Heiko Carstens <heiko.carstens@de.ibm.com> |
s390/topology: cleanup topology code Mainly merge all different per-cpu arrays into a single array which holds all topology information per logical cpu. Also fix the broken core vs socket variable naming and simplify the locking a bit. When running in environments without topology information also invent book, socket and core ids, so that not all ids are zero. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
|
658e5ce705f2a09ab681eb61ca7c8619bb7a783d |
|
10-Nov-2012 |
Heiko Carstens <heiko.carstens@de.ibm.com> |
s390/topology: fix core id vs physical package id mix-up The current topology code confuses core id vs physical package id. In other words /sys/devices/system/cpu/cpuX/topology/core_id displays the physical_package_id (aka socket id) instead of the core id. The physical_package_id sysfs attribute always displays "-1" instead of the socket id. Fix this mix-up with a small patch which defines and initializes topology_physical_package_id correctly and fixes the broken core id handling. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
|
0327dab0e88b2f4be6ad7dcd5af86d085d2c0603 |
|
14-Sep-2012 |
Wei Yongjun <yongjun_wei@trendmicro.com.cn> |
s390/topology: use for_each_set_bit to simplify the code Use for_each_set_bit() to simplify the code. spatch with a semantic match is used to found this. (http://coccinelle.lip6.fr/) Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
|
50ab9a9a60fc83b8e8db36b54f365226e2b139ac |
|
04-Sep-2012 |
Heiko Carstens <heiko.carstens@de.ibm.com> |
s390/smp,topology: add polarization member to pcpu struct The cpu polarization member is the only per cpu state that is not part of the pcpu structure. So add it there and have everything in one place. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
|
fade4dc49101e3b68fb375fd2b00d0ef1f31a36f |
|
04-Sep-2012 |
Heiko Carstens <heiko.carstens@de.ibm.com> |
s390/sysinfo,topology: fix cpu topology maximum nesting detection The maximum nesting of the cpu topology is evaluated when /proc/sysinfo is the first time read. This happens without a lock and a concurrent reader on a different cpu can see and use an invalid intermediate value. Besides the fact that this race is quite unlikely the worst thing that could happen is that /proc/sysinfo would contain bogus information about the machine's cpu topology. Nevertheless this should be fixed. So move the detection code to the early machine detection code and since now the value is early available use it in the topology code as well. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
|
78609132795b4e3d6d51c6b67d461bf1626afb2f |
|
03-Sep-2012 |
Heiko Carstens <heiko.carstens@de.ibm.com> |
s390/topology: remove sysinfo header include, add forward declaration instead Any change to sysinfo.h causes a whole kernel recompile since sysinfo.h is included by topology.h, which again is used nearly everywhere. So remove that include and add a forward declaration instead. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
|
a53c8fab3f87c995c30ac226a03af95361243144 |
|
20-Jul-2012 |
Heiko Carstens <heiko.carstens@de.ibm.com> |
s390/comments: unify copyright messages and remove file names Remove the file name from the comment at top of many files. In most cases the file name was wrong anyway, so it's rather pointless. Also unify the IBM copyright statement. We did have a lot of sightly different statements and wanted to change them one after another whenever a file gets touched. However that never happened. Instead people start to take the old/"wrong" statements to use as a template for new files. So unify all of them in one go. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
|
8b646bd759086f6090fe27acf414c0b5faa737f4 |
|
11-Mar-2012 |
Martin Schwidefsky <schwidefsky@de.ibm.com> |
[S390] rework smp code Define struct pcpu and merge some of the NR_CPUS arrays into it, including __cpu_logical_map, current_set and smp_cpu_state. Split smp related functions to those operating on physical cpus and the functions operating on a logical cpu number. Make the functions for physical cpus use a pointer to a struct pcpu. This hides the knowledge about cpu addresses in smp.c, entry[64].S and swsusp_asm64.S, thus remove the sigp.h header. The PSW restart mechanism is used to start secondary cpus, calling a function on an online cpu, calling a function on the ipl cpu, and for the nmi signal. Replace the different assembler functions with a single function restart_int_handler. The new entry point calls a function whose pointer is stored in the lowcore of the target cpu and it can wait for the source cpu to stop. This covers all existing use cases. Overall the code is now simpler and there are ~380 lines less code. Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
|
d68bddb7329a4d47d950d6b0745a7e274d230ed4 |
|
27-Dec-2011 |
Heiko Carstens <heiko.carstens@de.ibm.com> |
[S390] topology: increase poll frequency if change is anticipated Increase cpu topology change poll frequency if a change is anticipated. Otherwise a user might be a bit confused to have to wait up to a minute in order to see a change this should be visible immediatly. However there is no guarantee that the change will happen during the time frame the poll frequency is increased. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
|
4baeb964d96d38dff461af5b9d578f0a9ba67617 |
|
27-Dec-2011 |
Heiko Carstens <heiko.carstens@de.ibm.com> |
[S390] topology: cleanup z10 topology handling Cleanup z10 topology handling. This adds some more code but hopefully the result is more readable and easier to maintain. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
|
83a24e32908476c33ea9abc132c73020e2cd3620 |
|
27-Dec-2011 |
Heiko Carstens <heiko.carstens@de.ibm.com> |
[S390] topology: get rid of ifdefs Remove all ifdefs from topology code and also only compile it for the CONFIG_SCHED_BOOK case. The new code selects SCHED_MC if SCHED_BOOK is selected. SCHED_MC without SCHED_BOOK is not possible anymore. Furthermore various sysfs attributes are not available anymore for the !SCHED_BOOK case. In particular all attributes that correspond to CPU polarization. But since all real world kernels have SCHED_BOOK selected anyway this doesn't matter too much. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
|
8a25a2fd126c621f44f3aeaef80d51f00fc11639 |
|
21-Dec-2011 |
Kay Sievers <kay.sievers@vrfy.org> |
cpu: convert 'cpu' and 'machinecheck' sysdev_class to a regular subsystem This moves the 'cpu sysdev_class' over to a regular 'cpu' subsystem and converts the devices to regular devices. The sysdev drivers are implemented as subsystem interfaces now. After all sysdev classes are ported to regular driver core entities, the sysdev implementation will be entirely removed from the kernel. Userspace relies on events and generic sysfs subsystem infrastructure from sysdev devices, which are made available with this conversion. Cc: Haavard Skinnemoen <hskinnemoen@gmail.com> Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no> Cc: Tony Luck <tony.luck@intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Paul Mundt <lethal@linux-sh.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Borislav Petkov <bp@amd64.org> Cc: Tigran Aivazian <tigran@aivazian.fsnet.co.uk> Cc: Len Brown <lenb@kernel.org> Cc: Zhang Rui <rui.zhang@intel.com> Cc: Dave Jones <davej@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Russell King <rmk+kernel@arm.linux.org.uk> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: "Srivatsa S. Bhat" <srivatsa.bhat@linux.vnet.ibm.com> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
|
f6bf1a8acd2cb3a92a7b7c9ab03e56a32ac5ece5 |
|
14-Nov-2011 |
Heiko Carstens <heiko.carstens@de.ibm.com> |
[S390] topology: fix topology on z10 machines Make sure that all cpus in a book on a z10 appear as book siblings and not as core siblings. This fixes some performance regressions that appeared after the book scheduling domain got introduced. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
|
caa04f69df9a5d4c10867b475006cf6f2f1e8500 |
|
30-Oct-2011 |
Sebastian Ott <sebott@linux.vnet.ibm.com> |
[S390] topology: fix alloc_masks annotation Fix this warning: WARNING: vmlinux.o(.text+0x199b6): Section mismatch in reference from the function alloc_masks() to the function .init.text:__alloc_bootmem() Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
|
d7b250e2a2d7f3cd23cf8d8d6689285e6f51a98d |
|
26-May-2011 |
Heiko Carstens <heiko.carstens@de.ibm.com> |
[S390] irq: merge irq.c and s390_ext.c Merge irq.c and s390_ext.c into irq.c. That way all external interrupt related functions are together. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
|
0f1959f50646612b247d624bdbf8b0c8816f2a93 |
|
23-May-2011 |
KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> |
[S390] convert old cpumask API into new one Adapt new API. Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
|
0b52783d4feb14d6ff990a63512a66d6131d41f9 |
|
29-Oct-2010 |
Heiko Carstens <heiko.carstens@de.ibm.com> |
[S390] topology: fix cpu masks for topology=off case Fix cpu masks for 'topology=off' case. Folding of the scheduling domains happen in such a way that everything belongs to the MC domain instead of the CPU doimain. This should fix a performance regression introduced with eafd2b6d "[S390] topology: use default MC domain initializer" and also makes sure we have the same behavious as if CONFIG_SCHED_MC was not selected at all. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
|
96f4a70d8eb4d746b19d5b5510407c8ff0d00340 |
|
25-Oct-2010 |
Heiko Carstens <heiko.carstens@de.ibm.com> |
[S390] topology: export cpu topology via proc/sysinfo Export the cpu configuration topology via sysinfo. Two new lines are introduced: CPU Topology HW: 0 0 0 4 6 4 CPU Topology SW: 0 0 0 0 4 24 The HW line describes the cpu topology nesting levels when the maximum nesting level is used to get the corresponding SYSIB. The SW line describes what Linux is actually using. In this case it supports only two levels (CONFIG_SCHED_BOOK off) and therefore the hardware folded the two lower levels in the SYSIB response block. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
|
c30f91b6a264aef9ffb05e13931514c2a988c495 |
|
25-Oct-2010 |
Heiko Carstens <heiko.carstens@de.ibm.com> |
[S390] topology: move topology sysinfo code Move the topology sysinfo SYSIB definitions to the proper place in asm/sysinfo.h where they should be. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
|
9186d7a9cfd75e51ac4db4a40e0a558371988bd2 |
|
25-Oct-2010 |
Heiko Carstens <heiko.carstens@de.ibm.com> |
[S390] topology: clean up facility detection Move cpu topology facility detection to early setup code where it should be. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
|
14375bc4eb8dd0fb0e765390650564c35bb31068 |
|
25-Oct-2010 |
Martin Schwidefsky <schwidefsky@de.ibm.com> |
[S390] cleanup facility list handling Store the facility list once at system startup with stfl/stfle and reuse the result for all facility tests. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
|
c9af3fa9e1e3e5154649991a14b74f3a2dee19ee |
|
25-Oct-2010 |
Heiko Carstens <heiko.carstens@de.ibm.com> |
[S390] topology: change default Switch default value of the kernel parameter 'topology' from off to on. Various performance measurements have finally shown that there are no (known) regressions anywhere. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
|
4cb14bc8c54f8489251d5cba8328cb410ead0cea |
|
31-Aug-2010 |
Heiko Carstens <heiko.carstens@de.ibm.com> |
topology, s390: Add z11 cpu topology support Use the extended cpu topology information that z11 machines provide to improve the scheduler's decision making. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <20100831082844.604956770@de.ibm.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
|
10d3858950557cd3cc05f647ede597114c610177 |
|
17-May-2010 |
Heiko Carstens <heiko.carstens@de.ibm.com> |
[S390] topology: expose core identifier Provide a topology_core_id define which makes sure that the contents of /sys/devices/system/cpu/cpuX/topology/core_id indeed do contain the core id and not always 0. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
|
d7015c120e0ac55d86cabbe7a14997b99f39e282 |
|
09-Apr-2010 |
Julia Lawall <julia@diku.dk> |
[S390] arch/s390/kernel: Add missing unlock In the default case the lock is not unlocked. The return is converted to a goto, to share the unlock at the end of the function. A simplified version of the semantic patch that finds this problem is as follows: (http://coccinelle.lip6.fr/) // <smpl> @r exists@ expression E1; identifier f; @@ f (...) { <+... * spin_lock_irq (E1,...); ... when != E1 * return ...; ...+> } // </smpl> Signed-off-by: Julia Lawall <julia@diku.dk> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
|
fb380aadfe34e8d3ce628cb3e386882351940874 |
|
13-Jan-2010 |
Heiko Carstens <heiko.carstens@de.ibm.com> |
[S390] Move __cpu_logical_map to smp.c Finally move it to the place where it belongs to and make get rid of it for !CONFIG_SMP. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
|
6f7a321d5feb0bc9aa7f7b14eceb1e6a63bff937 |
|
26-Mar-2009 |
Rusty Russell <rusty@rustcorp.com.au> |
[S390] cpumask: remove cpu_coregroup_map Impact: cleanup cpu_coregroup_mask is the New Hotness. As S/390 uses theirs internally, so we just make it static. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
|
9be3eec2c83848a1ca57ebad13c63c95d0df01e2 |
|
26-Dec-2008 |
Rusty Russell <rusty@rustcorp.com.au> |
cpumask: cpu_coregroup_mask(): s390 Like cpu_coregroup_map, but returns a (const) pointer. Compile-tested on s390 (defconfig). Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Mike Travis <travis@sgi.com>
|
395d31d40cc38270dd7c024691404e2eddf0678d |
|
25-Dec-2008 |
Martin Schwidefsky <schwidefsky@de.ibm.com> |
[S390] convert cpu related printks to pr_xxx macros. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
|
349f1b671a4b2612c1355612bedadc81f86d26f1 |
|
25-Dec-2008 |
Heiko Carstens <heiko.carstens@de.ibm.com> |
[S390] cpu topology: remove dead code Interrupts haven't been implemented. So remove the dead code. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
|
2b1a61f0a8c714c96277bf16a823a84bafa1397d |
|
25-Dec-2008 |
Heiko Carstens <heiko.carstens@de.ibm.com> |
[S390] cpu topology: introduce kernel parameter Introduce a topology=[on|off] kernel parameter which allows to switch cpu topology on/off. Default will be off, since it looks like that for some workloards this doesn't behave very well (on s390). Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
|
f414f5f15376764d68a31dc568d9e814d3fcb58a |
|
25-Dec-2008 |
Heiko Carstens <heiko.carstens@de.ibm.com> |
[S390] cpu topology: dont destroy cpu sets on topology change Call rebuild_sched_domains instead of arch_reinit_sched_domains if cpu topology changes. This leaves cpu sets alone which otherwise would be destroyed. If and how it makes sense to define cpu sets on a virtualized architecture is another question. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
|
5439050f9f1aa92381ab9beccbea6ddf0c687c2b |
|
25-Dec-2008 |
Heiko Carstens <heiko.carstens@de.ibm.com> |
[S390] cpu topology: fix cpu_core_map initialization Common code doesn't call arch_update_cpu_topology() anymore on cpu hotplug. But our architecture backend relied on that in order to update the cpu_core_map. For machines without cpu topology support this leads uninitialized cpu_core_maps for later on added cpus. To solve this just initialize the maps with cpu_possible_map, since that will be always valid for machines without topology support. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
|
ee79d1bdb6a10499e53f80b1e8d14110215178ba |
|
09-Dec-2008 |
Heiko Carstens <heiko.carstens@de.ibm.com> |
sched: let arch_update_cpu_topology indicate if topology changed Change arch_update_cpu_topology so it returns 1 if the cpu topology changed and 0 if it didn't change. This will be useful for the next patch which adds a call to this function in partition_sched_domains. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
|
74af283102b358b0da545460d0d176f473e110f6 |
|
14-Nov-2008 |
Heiko Carstens <heiko.carstens@de.ibm.com> |
[S390] cpu topology: fix locking cpu_coregroup_map used to grab a mutex on s390 since it was only called from process context. Since c7c22e4d5c1fdebfac4dba76de7d0338c2b0d832 "block: add support for IO CPU affinity" this is not true anymore. It now also gets called from softirq context. To prevent possible deadlocks change this in architecture code and use a spinlock instead of a mutex. Cc: stable@kernel.org Cc: Jens Axboe <jens.axboe@oracle.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
|
69b895fd13d73aebf62b75502eb6513d43057ba3 |
|
25-Jul-2008 |
Oleg Nesterov <oleg@tv-sign.ru> |
S390 topology: don't use kthread() for arch_reinit_sched_domains() Now that it is safe to use get_online_cpus() we can revert [S390] cpu topology: Fix possible deadlock. commit: fd781fa25c9e9c6fd1599df060b05e7c4ad724e5 and call arch_reinit_sched_domains() directly from topology_work_fn(). Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru> Cc: Gautham R Shenoy <ego@in.ibm.com> Tested-by: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Max Krasnyansky <maxk@qualcomm.com> Cc: Paul Jackson <pj@sgi.com> Cc: Paul Menage <menage@google.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Vegard Nossum <vegard.nossum@gmail.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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402a3998ba6ba81bae6ac586ada55a0dd6a7c287 |
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14-Jul-2008 |
Julia Lawall <julia@diku.dk> |
[S390] arch/s390: Eliminate NULL test and memset after alloc_bootmem As noted by Akinobu Mita in patch b1fceac2b9e04d278316b2faddf276015fc06e3b, alloc_bootmem and related functions never return NULL and always return a zeroed region of memory. Thus a NULL test or memset after calls to these functions is unnecessary. arch/s390/kernel/topology.c | 2 -- 1 file changed, 2 deletions(-) This was fixed using the following semantic patch. (http://www.emn.fr/x-info/coccinelle/) // <smpl> @@ expression E; statement S; @@ E = \(alloc_bootmem\|alloc_bootmem_low\|alloc_bootmem_pages\|alloc_bootmem_low_pages\)(...) ... when != E ( - BUG_ON (E == NULL); | - if (E == NULL) S ) @@ expression E,E1; @@ E = \(alloc_bootmem\|alloc_bootmem_low\|alloc_bootmem_pages\|alloc_bootmem_low_pages\)(...) ... when != E - memset(E,0,E1); // </smpl> Signed-off-by: Julia Lawall <julia@diku.dk> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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fd781fa25c9e9c6fd1599df060b05e7c4ad724e5 |
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30-Apr-2008 |
Heiko Carstens <heiko.carstens@de.ibm.com> |
[S390] cpu topology: Fix possible deadlock. When we get a notification that cpu topology changed, we schedule a work struct which just calls arch_reinit_sched_domains. This function in turn calls get_online_cpus() which results int the lockdep warning below. After all it turnded out that it's not legal to call get_online_cpus() from the context of a multi-threaded work queue. It could deadlock this way: process 0 (events/cpu-x): -> run_workqueue -> removes my work_struct from the work queue -> calls work_struct->fn -> get_online_cpus() -> locks on cpu_hotplug.lock since process 1 below is doing cpu hotplug process 1: -> cpu_down (for cpu-x) -> cpu_hotplug_begin (holds cpu_hotplug.lock now) -> cpu-x dead -> notifier_call_chain with CPU_DEAD -> cleanup_workqueue_thread -> flush_cpu_workqueue (succeeds) -> kthread_stop for events/cpu-x -> now kthread_stop waits for my work_struct to complete from within process 0. -> dead. A single threaded workqueue wouldn't have such problems, however there is no such common queue available and it's not worth to create one for the very rare calls to arch_reinit_sched_domains. So we just create a kernel thread from our work struct which calls arch_reinit_sched_domains and are done with it. Thanks to Oleg Nesterov and Peter Zijlstra for helping me figuring out that this isn't a false positive lockdep warning: ======================================================= [ INFO: possible circular locking dependency detected ] 2.6.25-03562-g3dc5063-dirty #12 ------------------------------------------------------- events/3/14 is trying to acquire lock: (&cpu_hotplug.lock){--..}, at: [<0000000000076094>] get_online_cpus+0x50/0x78 but task is already holding lock: (topology_work){--..}, at: [<0000000000059cde>] run_workqueue+0x106/0x278 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (topology_work){--..}: [<000000000006fc74>] __lock_acquire+0x1010/0x111c [<000000000006fe40>] lock_acquire+0xc0/0xf8 [<0000000000059d48>] run_workqueue+0x170/0x278 [<0000000000059edc>] worker_thread+0x8c/0xf0 [<000000000005f5bc>] kthread+0x68/0xa0 [<000000000001a33e>] kernel_thread_starter+0x6/0xc [<000000000001a338>] kernel_thread_starter+0x0/0xc -> #1 (events){--..}: [<000000000006fc74>] __lock_acquire+0x1010/0x111c [<000000000006fe40>] lock_acquire+0xc0/0xf8 [<000000000005a23c>] cleanup_workqueue_thread+0x60/0xa8 [<00000000003b2ab8>] workqueue_cpu_callback+0xbc/0x170 [<00000000003bba80>] notifier_call_chain+0x5c/0xa4 [<00000000000655a2>] __raw_notifier_call_chain+0x26/0x38 [<00000000000655e2>] raw_notifier_call_chain+0x2e/0x40 [<0000000000075e00>] cpu_down+0x228/0x31c [<00000000003b1dd8>] store_online+0x64/0xb8 [<00000000001e7128>] sysdev_store+0x48/0x58 [<0000000000121cd2>] sysfs_write_file+0x126/0x1c0 [<00000000000c1944>] vfs_write+0xb0/0x15c [<00000000000c20e6>] sys_write+0x56/0x88 [<0000000000027a68>] sys32_write+0x34/0x4c [<0000000000023f70>] sysc_noemu+0x10/0x16 [<0000000077f3f186>] 0x77f3f186 -> #0 (&cpu_hotplug.lock){--..}: [<000000000006fa84>] __lock_acquire+0xe20/0x111c [<000000000006fe40>] lock_acquire+0xc0/0xf8 [<00000000003b701c>] mutex_lock_nested+0xd0/0x364 [<0000000000076094>] get_online_cpus+0x50/0x78 [<000000000003a03e>] arch_reinit_sched_domains+0x26/0x58 [<000000000002700e>] topology_work_fn+0x26/0x34 [<0000000000059d4e>] run_workqueue+0x176/0x278 [<0000000000059edc>] worker_thread+0x8c/0xf0 [<000000000005f5bc>] kthread+0x68/0xa0 [<000000000001a33e>] kernel_thread_starter+0x6/0xc [<000000000001a338>] kernel_thread_starter+0x0/0xc other info that might help us debug this: 2 locks held by events/3/14: #0: (events){--..}, at: [<0000000000059cde>] run_workqueue+0x106/0x278 #1: (topology_work){--..}, at: [<0000000000059cde>] run_workqueue+0x106/0x278 stack backtrace: CPU: 3 Not tainted 2.6.25-03562-g3dc5063-dirty #12 Process events/3 (pid: 14, task: 000000002fb04038, ksp: 000000002fb0bd70) 0400000000000000 000000002fb0ba40 0000000000000002 0000000000000000 000000002fb0bae0 000000002fb0ba58 000000002fb0ba58 0000000000016488 0000000000000000 000000002fb0bd70 0000000000000000 0000000000000000 000000002fb0ba40 000000000000000c 000000002fb0ba40 000000002fb0bab0 00000000003c99e0 0000000000016488 000000002fb0ba40 000000002fb0ba90 Call Trace: ([<00000000000163fc>] show_trace+0x138/0x158) [<00000000000164e2>] show_stack+0xc6/0xf8 [<0000000000016624>] dump_stack+0xb0/0xc0 [<000000000006cd36>] print_circular_bug_tail+0xa2/0xb4 [<000000000006fa84>] __lock_acquire+0xe20/0x111c [<000000000006fe40>] lock_acquire+0xc0/0xf8 [<00000000003b701c>] mutex_lock_nested+0xd0/0x364 [<0000000000076094>] get_online_cpus+0x50/0x78 [<000000000003a03e>] arch_reinit_sched_domains+0x26/0x58 [<000000000002700e>] topology_work_fn+0x26/0x34 [<0000000000059d4e>] run_workqueue+0x176/0x278 [<0000000000059edc>] worker_thread+0x8c/0xf0 [<000000000005f5bc>] kthread+0x68/0xa0 [<000000000001a33e>] kernel_thread_starter+0x6/0xc [<000000000001a338>] kernel_thread_starter+0x0/0xc INFO: lockdep is turned off. Cc: Oleg Nesterov <oleg@tv-sign.ru> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
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d00aa4e7d0129983fc4389c85e15a066eb4e69a9 |
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30-Apr-2008 |
Heiko Carstens <heiko.carstens@de.ibm.com> |
[S390] Add topology_core_siblings to topology.h This exposes the core siblings to user space via sysfs. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
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c10fde0d9e2112c25052a8742e893ec5965c0007 |
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17-Apr-2008 |
Heiko Carstens <heiko.carstens@de.ibm.com> |
[S390] Vertical cpu management. If vertical cpu polarization is active then the hypervisor will dispatch certain cpus for a longer time than other cpus for maximum performance. For example if a guest would have three virtual cpus, each of them with a share of 33 percent, then in case of vertical cpu polarization all of the processing time would be combined to a single cpu which would run all the time, while the other two cpus would get nearly no cpu time. There are three different types of vertical cpus: high, medium and low. Low cpus hardly get any real cpu time, while high cpus get a full real cpu. Medium cpus get something in between. In order to switch between the two possible modes (default is horizontal) a 0 for horizontal polarization or a 1 for vertical polarization must be written to the dispatching sysfs attribute: /sys/devices/system/cpu/dispatching The polarization of each single cpu can be figured out by the polarization sysfs attribute of each cpu: /sys/devices/system/cpu/cpuX/polarization horizontal, vertical:high, vertical:medium, vertical:low or unknown. When switching polarization the polarization attribute may contain the value unknown until the configuration change is done and the kernel has figured out the new polarization of each cpu. Note that running a system with different types of vertical cpus may result in significant performance regressions. If possible only one type of vertical cpus should be used. All other cpus should be offlined. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
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dbd70fb499952d0ba282f0159dafacfc31d50313 |
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17-Apr-2008 |
Heiko Carstens <heiko.carstens@de.ibm.com> |
[S390] cpu topology support for s390. Add s390 backend so we can give the scheduler some hints about the cpu topology. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
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