kernel-ark/arch/mips/kernel/smp-up.c

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/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 2006, 07 by Ralf Baechle (ralf@linux-mips.org)
*
* Symmetric Uniprocessor (TM) Support
*/
#include <linux/kernel.h>
#include <linux/sched.h>
/*
* Send inter-processor interrupt
*/
static void up_send_ipi_single(int cpu, unsigned int action)
{
panic(KERN_ERR "%s called", __func__);
}
static inline void up_send_ipi_mask(const struct cpumask *mask,
unsigned int action)
{
panic(KERN_ERR "%s called", __func__);
}
/*
* After we've done initial boot, this function is called to allow the
* board code to clean up state, if needed
*/
MIPS: Delete __cpuinit/__CPUINIT usage from MIPS code commit 3747069b25e419f6b51395f48127e9812abc3596 upstream. The __cpuinit type of throwaway sections might have made sense some time ago when RAM was more constrained, but now the savings do not offset the cost and complications. For example, the fix in commit 5e427ec2d0 ("x86: Fix bit corruption at CPU resume time") is a good example of the nasty type of bugs that can be created with improper use of the various __init prefixes. After a discussion on LKML[1] it was decided that cpuinit should go the way of devinit and be phased out. Once all the users are gone, we can then finally remove the macros themselves from linux/init.h. Note that some harmless section mismatch warnings may result, since notify_cpu_starting() and cpu_up() are arch independent (kernel/cpu.c) and are flagged as __cpuinit -- so if we remove the __cpuinit from the arch specific callers, we will also get section mismatch warnings. As an intermediate step, we intend to turn the linux/init.h cpuinit related content into no-ops as early as possible, since that will get rid of these warnings. In any case, they are temporary and harmless. Here, we remove all the MIPS __cpuinit from C code and __CPUINIT from asm files. MIPS is interesting in this respect, because there are also uasm users hiding behind their own renamed versions of the __cpuinit macros. [1] https://lkml.org/lkml/2013/5/20/589 [ralf@linux-mips.org: Folded in Paul's followup fix.] Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/5494/ Patchwork: https://patchwork.linux-mips.org/patch/5495/ Patchwork: https://patchwork.linux-mips.org/patch/5509/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2013-06-18 13:38:59 +00:00
static void up_init_secondary(void)
{
}
MIPS: Delete __cpuinit/__CPUINIT usage from MIPS code commit 3747069b25e419f6b51395f48127e9812abc3596 upstream. The __cpuinit type of throwaway sections might have made sense some time ago when RAM was more constrained, but now the savings do not offset the cost and complications. For example, the fix in commit 5e427ec2d0 ("x86: Fix bit corruption at CPU resume time") is a good example of the nasty type of bugs that can be created with improper use of the various __init prefixes. After a discussion on LKML[1] it was decided that cpuinit should go the way of devinit and be phased out. Once all the users are gone, we can then finally remove the macros themselves from linux/init.h. Note that some harmless section mismatch warnings may result, since notify_cpu_starting() and cpu_up() are arch independent (kernel/cpu.c) and are flagged as __cpuinit -- so if we remove the __cpuinit from the arch specific callers, we will also get section mismatch warnings. As an intermediate step, we intend to turn the linux/init.h cpuinit related content into no-ops as early as possible, since that will get rid of these warnings. In any case, they are temporary and harmless. Here, we remove all the MIPS __cpuinit from C code and __CPUINIT from asm files. MIPS is interesting in this respect, because there are also uasm users hiding behind their own renamed versions of the __cpuinit macros. [1] https://lkml.org/lkml/2013/5/20/589 [ralf@linux-mips.org: Folded in Paul's followup fix.] Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/5494/ Patchwork: https://patchwork.linux-mips.org/patch/5495/ Patchwork: https://patchwork.linux-mips.org/patch/5509/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2013-06-18 13:38:59 +00:00
static void up_smp_finish(void)
{
}
/*
* Firmware CPU startup hook
*/
static int up_boot_secondary(int cpu, struct task_struct *idle)
{
return 0;
}
static void __init up_smp_setup(void)
{
}
static void __init up_prepare_cpus(unsigned int max_cpus)
{
}
#ifdef CONFIG_HOTPLUG_CPU
static int up_cpu_disable(void)
{
return -ENOSYS;
}
static void up_cpu_die(unsigned int cpu)
{
BUG();
}
#endif
MIPS: SMP: Constify smp ops 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 <matt.redfearn@imgtec.com> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Marcin Nowakowski <marcin.nowakowski@imgtec.com> Cc: Bart Van Assche <bart.vanassche@sandisk.com> Cc: Masahiro Yamada <yamada.masahiro@socionext.com> Cc: Huacai Chen <chenhc@lemote.com> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Kevin Cernekee <cernekee@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Doug Ledford <dledford@redhat.com> Cc: James Hogan <james.hogan@imgtec.com> Cc: Joe Perches <joe@perches.com> Cc: Florian Fainelli <f.fainelli@gmail.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Paul Burton <paul.burton@imgtec.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Steven J. Hill <steven.hill@cavium.com> 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 <ralf@linux-mips.org>
2017-07-19 08:21:03 +00:00
const struct plat_smp_ops up_smp_ops = {
.send_ipi_single = up_send_ipi_single,
.send_ipi_mask = up_send_ipi_mask,
.init_secondary = up_init_secondary,
.smp_finish = up_smp_finish,
.boot_secondary = up_boot_secondary,
.smp_setup = up_smp_setup,
.prepare_cpus = up_prepare_cpus,
#ifdef CONFIG_HOTPLUG_CPU
.cpu_disable = up_cpu_disable,
.cpu_die = up_cpu_die,
#endif
};