kernel/linux.git/arch/mips/include/asm/smp.h, branch v6.2.2

MIPS: arch_send_call_function_single_ipi() calling conventions change

2020-04-24T16:27:51+00:00

Use mp_ops->send_ipi_single() instead of mp_ops->send_ipi_mask() in arch_send_call_function_single_ipi(). send_ipi_single() can send IPI signal to a special cpu more efficiently. Signed-off-by: Liangliang Huang Reviewed-by: Huacai Chen Signed-off-by: Thomas Bogendoerfer

MIPS: kexec: Make a framework for both jumping and halting on nonboot CPUs

2018-09-22T17:31:50+00:00

The existing implementation lets machine_kexec() CPU jump to reboot code buffer, whereas other CPUs to relocated_kexec_smp_wait. The natural way to bring up an SMP new kernel would be to let CPU0 do it while others being halted. For those failing to do so, fall back to the jumping method. Signed-off-by: Dengcheng Zhu [paul.burton@mips.com: Guard kexec_nonboot_cpu_jump with CONFIG_SMP] Signed-off-by: Paul Burton Patchwork: https://patchwork.linux-mips.org/patch/20570/ Cc: pburton@wavecomp.com Cc: ralf@linux-mips.org Cc: linux-mips@linux-mips.org Cc: rachel.mozes@intel.com

MIPS: VDSO: Prevent use of smp_processor_id()

2018-07-28T02:36:16+00:00

VDSO code should not be using smp_processor_id(), since it is executed in user mode. Introduce a VDSO-specific path which will cause a compile-time or link-time error (depending upon support for __compiletime_error) if the VDSO ever incorrectly attempts to use smp_processor_id(). [Matt Redfearn : Move before change to smp_processor_id in series] Signed-off-by: Paul Burton Signed-off-by: Matt Redfearn Patchwork: https://patchwork.linux-mips.org/patch/17932/ Cc: Ralf Baechle Cc: James Hogan Cc: linux-mips@linux-mips.org

MIPS: Allow __cpu_number_map to be larger than NR_CPUS

2017-11-07T18:32:10+00:00

In systems where the CPU id space is sparse, this allows a smaller NR_CPUS to be chosen, thus keeping internal data structures smaller. Signed-off-by: David Daney Signed-off-by: Carlos Munoz Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/17388/ [jhogan@kernel.org: Add depends on SMP to fix "warning: symbol value '' invalid for MIPS_NR_CPU_NR_MAP"] Signed-off-by: James Hogan

MIPS: SMP: Constify smp ops

2017-08-29T13:21:50+00:00

smp_ops providers do not modify their ops structures, so they should be made const for robustness. Since currently the MIPS kernel is not mapped with memory protection, this does not in itself provide any security benefit, but it still makes sense to make this change. There are also slight code size efficincies from the structure being made read-only, saving 128 bytes of kernel text on a pistachio_defconfig. Before: text data bss dec hex filename 7187239 1772752 470224 9430215 8fe4c7 vmlinux After: text data bss dec hex filename 7187111 1772752 470224 9430087 8fe447 vmlinux Signed-off-by: Matt Redfearn Cc: Sebastian Andrzej Siewior Cc: Arnd Bergmann Cc: Marcin Nowakowski Cc: Bart Van Assche Cc: Masahiro Yamada Cc: Huacai Chen Cc: Paul Gortmaker Cc: Kevin Cernekee Cc: Thomas Gleixner Cc: Doug Ledford Cc: James Hogan Cc: Joe Perches Cc: Florian Fainelli Cc: Ingo Molnar Cc: Paul Burton Cc: Andrew Morton Cc: Steven J. Hill Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/16784/ Signed-off-by: Ralf Baechle

MIPS: SMP: move asmlinkage before return type

2017-07-12T23:26:04+00:00

Make the code like the rest of the kernel. Link: http://lkml.kernel.org/r/756d3fb543e981b9284e756fa27616725a354b28.1499284835.git.joe@perches.com Signed-off-by: Joe Perches Cc: Ralf Baechle Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

MIPS: kexec: remove SMP_DUMP

2017-01-03T15:34:44+00:00

SMP_DUMP has been added as a new IPI signal when kexec support was added for Cavium Octeon CPUs ('commit 7aa1c8f47e7e ("MIPS: kdump: Add support")'. However, the new signal doesn't appear to ever have a proper handler added (octeon_message_functions[] array has an empty handler for it), and generic IPI handlers now trigger a BUG() on unhandled signal. As the method is unused remove it completely and replace its only invocation with a smp_call_function(). [ralf@linux-mips.org: Renumber SMP_ASK_C0COUNT to avoid numbering gaps.] Signed-off-by: Marcin Nowakowski Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/14630/ Signed-off-by: Ralf Baechle

MIPS: SMP: Remove cpu_callin_map

2017-01-03T15:34:38+00:00

The previous commit made cpu_callin_map redundant, since it is no longer used to signal secondary CPUs starting, or going offline. Remove it now. Signed-off-by: Matt Redfearn Cc: Sebastian Andrzej Siewior Cc: Qais Yousef Cc: Masahiro Yamada Cc: Huacai Chen Cc: Kevin Cernekee Cc: Thomas Gleixner Cc: Andrew Morton Cc: James Hogan Cc: Paul Burton Cc: Florian Fainelli Cc: Anna-Maria Gleixner Cc: Adam Buchbinder Cc: Yang Shi Cc: David Daney Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/14503/ Signed-off-by: Ralf Baechle

MIPS: smp.c: Introduce mechanism for freeing and allocating IPIs

2016-10-04T23:31:20+00:00

For the MIPS remote processor implementation, we need additional IPIs to talk to the remote processor. Since MIPS GIC reserves exactly the right number of IPI IRQs required by Linux for the number of VPs in the system, this is not possible without releasing some recources. This commit introduces mips_smp_ipi_allocate() which allocates IPIs to a given cpumask. It is called as normal with the cpu_possible_mask at bootup to initialise IPIs to all CPUs. mips_smp_ipi_free() may then be used to free IPIs to a subset of those CPUs so that their hardware resources can be reused. Signed-off-by: Matt Redfearn Cc: Bjorn Andersson Cc: Ohad Ben-Cohen Cc: Thomas Gleixner Cc: Lisa Parratt Cc: James Hogan Cc: Qais Yousef Cc: Paul Burton Cc: linux-mips@linux-mips.org Cc: linux-remoteproc@vger.kernel.org Cc: lisa.parratt@imgtec.com Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/14285/ Signed-off-by: Ralf Baechle

MIPS: c-r4k: Exclude sibling CPUs in SMP calls

2016-07-29T08:19:29+00:00

When performing SMP calls to foreign cores, exclude sibling CPUs from the provided map, as we already handle the local core on the current CPU. This prevents an SMP call from for example core 0, VPE 1 to VPE 0 on the same core. In the process the cpu_foreign_map cpumask is turned into an array of cpumasks, so that each CPU has its own version of it which excludes sibling CPUs. r4k_op_needs_ipi() is also updated to reflect that cache management SMP calls are not needed when all CPUs are siblings (i.e. there are no foreign CPUs according to the new cpu_foreign_map[] semantics which exclude siblings). Signed-off-by: James Hogan Cc: Paul Burton Cc: Leonid Yegoshin Cc: Felix Fietkau Cc: Jayachandran C. Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/13801/ Signed-off-by: Ralf Baechle