linux.git/arch/xtensa/kernel/smp.c, branch v4.4.183 Clone of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git xtensa: SMP: limit number of possible CPUs by NR_CPUS 2019-03-23T07:44:25+00:00 Max Filippov jcmvbkbc@gmail.com 2019-01-27T04:35:18+00:00 3afc8b84643848f9d195d9856f12b620fd9a9c95 [ Upstream commit 25384ce5f9530def39421597b1457d9462df6455 ] This fixes the following warning at boot when the kernel is booted on a board with more CPU cores than was configured in NR_CPUS: smp_init_cpus: Core Count = 8 smp_init_cpus: Core Id = 0 ------------[ cut here ]------------ WARNING: CPU: 0 PID: 0 at include/linux/cpumask.h:121 smp_init_cpus+0x54/0x74 Modules linked in: CPU: 0 PID: 0 Comm: swapper Not tainted 5.0.0-rc3-00015-g1459333f88a0 #124 Call Trace: __warn$part$3+0x6a/0x7c warn_slowpath_null+0x35/0x3c smp_init_cpus+0x54/0x74 setup_arch+0x1c0/0x1d0 start_kernel+0x44/0x310 _startup+0x107/0x107 Signed-off-by: Max Filippov <jcmvbkbc@gmail.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 25384ce5f9530def39421597b1457d9462df6455 ]

This fixes the following warning at boot when the kernel is booted on a
board with more CPU cores than was configured in NR_CPUS:

  smp_init_cpus: Core Count = 8
  smp_init_cpus: Core Id = 0
  ------------[ cut here ]------------
  WARNING: CPU: 0 PID: 0 at include/linux/cpumask.h:121 smp_init_cpus+0x54/0x74
  Modules linked in:
  CPU: 0 PID: 0 Comm: swapper Not tainted 5.0.0-rc3-00015-g1459333f88a0 #124
  Call Trace:
    __warn$part$3+0x6a/0x7c
    warn_slowpath_null+0x35/0x3c
    smp_init_cpus+0x54/0x74
    setup_arch+0x1c0/0x1d0
    start_kernel+0x44/0x310
    _startup+0x107/0x107

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
xtensa: SMP: mark each possible CPU as present 2019-03-23T07:44:25+00:00 Max Filippov jcmvbkbc@gmail.com 2019-01-19T08:26:48+00:00 19960e19a7f903062d8191a5773611e313f889b9 [ Upstream commit 8b1c42cdd7181200dc1fff39dcb6ac1a3fac2c25 ] Otherwise it is impossible to enable CPUs after booting with 'maxcpus' parameter. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 8b1c42cdd7181200dc1fff39dcb6ac1a3fac2c25 ]

Otherwise it is impossible to enable CPUs after booting with 'maxcpus'
parameter.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
xtensa: SMP: fix secondary CPU initialization 2019-03-23T07:44:25+00:00 Max Filippov jcmvbkbc@gmail.com 2018-12-21T16:26:20+00:00 56b84e4201894b1cf68dc67b88d20f9493bf3072 [ Upstream commit 32a7726c4f4aadfabdb82440d84f88a5a2c8fe13 ] - add missing memory barriers to the secondary CPU synchronization spin loops; add comment to the matching memory barrier in the boot_secondary and __cpu_die functions; - use READ_ONCE/WRITE_ONCE to access cpu_start_id/cpu_start_ccount instead of reading/writing them directly; - re-initialize cpu_running every time before starting secondary CPU to flush possible previous CPU startup results. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 32a7726c4f4aadfabdb82440d84f88a5a2c8fe13 ]

- add missing memory barriers to the secondary CPU synchronization spin
  loops; add comment to the matching memory barrier in the boot_secondary
  and __cpu_die functions;
- use READ_ONCE/WRITE_ONCE to access cpu_start_id/cpu_start_ccount
  instead of reading/writing them directly;
- re-initialize cpu_running every time before starting secondary CPU to
  flush possible previous CPU startup results.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
flush_icache_range: export symbol to fix build errors 2014-08-29T23:28:17+00:00 Pranith Kumar bobby.prani@gmail.com 2014-08-29T22:19:09+00:00 e3560305192cd51b3c07206c85eb4231594dd58b Fix building errors occuring due to a missing export of flush_icache_range() in kisskb.ellerman.id.au/kisskb/buildresult/11677809/ ERROR: "flush_icache_range" [drivers/misc/lkdtm.ko] undefined! Signed-off-by: Pranith Kumar <bobby.prani@gmail.com> Reported-by: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Vineet Gupta <vgupta@synopsys.com> [arc] Acked-by: Richard Kuo <rkuo@codeaurora.org> [hexagon] Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Chris Zankel <chris@zankel.net> Acked-by: Max Filippov <jcmvbkbc@gmail.com> [xtensa] Cc: Noam Camus <noamc@ezchip.com> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Acked-by: Zhigang Lu <zlu@tilera.com> [tile] Cc: Kirill Tkhai <tkhai@yandex.ru> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> 
Fix building errors occuring due to a missing export of
flush_icache_range() in

kisskb.ellerman.id.au/kisskb/buildresult/11677809/

ERROR: "flush_icache_range" [drivers/misc/lkdtm.ko] undefined!

Signed-off-by: Pranith Kumar <bobby.prani@gmail.com>
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Vineet Gupta <vgupta@synopsys.com>	[arc]
Acked-by: Richard Kuo <rkuo@codeaurora.org>	[hexagon]
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Chris Zankel <chris@zankel.net>
Acked-by: Max Filippov <jcmvbkbc@gmail.com>	[xtensa]
Cc: Noam Camus <noamc@ezchip.com>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Acked-by: Zhigang Lu <zlu@tilera.com>		[tile]
Cc: Kirill Tkhai <tkhai@yandex.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
xtensa: optimize local_flush_tlb_kernel_range 2014-04-06T17:29:17+00:00 Max Filippov jcmvbkbc@gmail.com 2014-02-14T10:08:48+00:00 04c6b3e2b5e5c1dbd99ad7620033eafd05ff4c26 Don't flush whole TLB if only a small kernel range is requested. Signed-off-by: Max Filippov <jcmvbkbc@gmail.com> 
Don't flush whole TLB if only a small kernel range is requested.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
xtensa: Enable irqs after cpu is set online 2014-01-14T20:12:41+00:00 Kirill Tkhai tkhai@yandex.ru 2013-12-12T13:41:01+00:00 abf0ea65e0adede5f40a836e6af7f62e7c850546 there is a small possibility that wake_up of softirq thread happens between local_irq_enable() and set_cpu_online(). In this case affinity of the thread changes to fallback affinity (i.e. CPU0). This may be a source of problems. The patch kills that possibility. Signed-off-by: Kirill Tkhai <tkhai@yandex.ru> Signed-off-by: Max Filippov <jcmvbkbc@gmail.com> 
there is a small possibility that wake_up of softirq thread
happens between local_irq_enable() and set_cpu_online(). In
this case affinity of the thread changes to fallback affinity
(i.e. CPU0). This may be a source of problems.

The patch kills that possibility.

Signed-off-by: Kirill Tkhai <tkhai@yandex.ru>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
xtensa: implement CPU hotplug 2014-01-14T18:19:59+00:00 Max Filippov jcmvbkbc@gmail.com 2013-10-16T22:42:28+00:00 49b424fedaf88d0fa9913082b8c1ccd012a8a972 Signed-off-by: Max Filippov <jcmvbkbc@gmail.com> Signed-off-by: Chris Zankel <chris@zankel.net> 
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
xtensa: add SMP support 2014-01-14T18:19:58+00:00 Max Filippov jcmvbkbc@gmail.com 2013-10-16T22:42:26+00:00 f615136c06a791364f5afa8b8ba965315a6440f1 This is largely based on SMP code from the xtensa-2.6.29-smp tree by Piet Delaney, Marc Gauthier, Joe Taylor, Christian Zankel (and possibly other Tensilica folks). Signed-off-by: Max Filippov <jcmvbkbc@gmail.com> Signed-off-by: Chris Zankel <chris@zankel.net> 
This is largely based on SMP code from the xtensa-2.6.29-smp tree by
Piet Delaney, Marc Gauthier, Joe Taylor, Christian Zankel (and possibly
other Tensilica folks).

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>