kernel_optimize_test/arch/powerpc/kernel/crash.c
Ingo Molnar d1bef4ed5f [PATCH] genirq: rename desc->handler to desc->chip
This patch-queue improves the generic IRQ layer to be truly generic, by adding
various abstractions and features to it, without impacting existing
functionality.

While the queue can be best described as "fix and improve everything in the
generic IRQ layer that we could think of", and thus it consists of many
smaller features and lots of cleanups, the one feature that stands out most is
the new 'irq chip' abstraction.

The irq-chip abstraction is about describing and coding and IRQ controller
driver by mapping its raw hardware capabilities [and quirks, if needed] in a
straightforward way, without having to think about "IRQ flow"
(level/edge/etc.) type of details.

This stands in contrast with the current 'irq-type' model of genirq
architectures, which 'mixes' raw hardware capabilities with 'flow' details.
The patchset supports both types of irq controller designs at once, and
converts i386 and x86_64 to the new irq-chip design.

As a bonus side-effect of the irq-chip approach, chained interrupt controllers
(master/slave PIC constructs, etc.) are now supported by design as well.

The end result of this patchset intends to be simpler architecture-level code
and more consolidation between architectures.

We reused many bits of code and many concepts from Russell King's ARM IRQ
layer, the merging of which was one of the motivations for this patchset.

This patch:

rename desc->handler to desc->chip.

Originally i did not want to do this, because it's a big patch.  But having
both "desc->handler", "desc->handle_irq" and "action->handler" caused a
large degree of confusion and made the code appear alot less clean than it
truly is.

I have also attempted a dual approach as well by introducing a
desc->chip alias - but that just wasnt robust enough and broke
frequently.

So lets get over with this quickly.  The conversion was done automatically
via scripts and converts all the code in the kernel.

This renaming patch is the first one amongst the patches, so that the
remaining patches can stay flexible and can be merged and split up
without having some big monolithic patch act as a merge barrier.

[akpm@osdl.org: build fix]
[akpm@osdl.org: another build fix]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-29 10:26:21 -07:00

213 lines
4.9 KiB
C

/*
* Architecture specific (PPC64) functions for kexec based crash dumps.
*
* Copyright (C) 2005, IBM Corp.
*
* Created by: Haren Myneni
*
* This source code is licensed under the GNU General Public License,
* Version 2. See the file COPYING for more details.
*
*/
#undef DEBUG
#include <linux/kernel.h>
#include <linux/smp.h>
#include <linux/reboot.h>
#include <linux/kexec.h>
#include <linux/bootmem.h>
#include <linux/crash_dump.h>
#include <linux/delay.h>
#include <linux/elf.h>
#include <linux/elfcore.h>
#include <linux/init.h>
#include <linux/irq.h>
#include <linux/types.h>
#include <asm/processor.h>
#include <asm/machdep.h>
#include <asm/kdump.h>
#include <asm/lmb.h>
#include <asm/firmware.h>
#include <asm/smp.h>
#ifdef DEBUG
#include <asm/udbg.h>
#define DBG(fmt...) udbg_printf(fmt)
#else
#define DBG(fmt...)
#endif
/* This keeps a track of which one is crashing cpu. */
int crashing_cpu = -1;
static u32 *append_elf_note(u32 *buf, char *name, unsigned type, void *data,
size_t data_len)
{
struct elf_note note;
note.n_namesz = strlen(name) + 1;
note.n_descsz = data_len;
note.n_type = type;
memcpy(buf, &note, sizeof(note));
buf += (sizeof(note) +3)/4;
memcpy(buf, name, note.n_namesz);
buf += (note.n_namesz + 3)/4;
memcpy(buf, data, note.n_descsz);
buf += (note.n_descsz + 3)/4;
return buf;
}
static void final_note(u32 *buf)
{
struct elf_note note;
note.n_namesz = 0;
note.n_descsz = 0;
note.n_type = 0;
memcpy(buf, &note, sizeof(note));
}
static void crash_save_this_cpu(struct pt_regs *regs, int cpu)
{
struct elf_prstatus prstatus;
u32 *buf;
if ((cpu < 0) || (cpu >= NR_CPUS))
return;
/* Using ELF notes here is opportunistic.
* I need a well defined structure format
* for the data I pass, and I need tags
* on the data to indicate what information I have
* squirrelled away. ELF notes happen to provide
* all of that that no need to invent something new.
*/
buf = (u32*)per_cpu_ptr(crash_notes, cpu);
if (!buf)
return;
memset(&prstatus, 0, sizeof(prstatus));
prstatus.pr_pid = current->pid;
elf_core_copy_regs(&prstatus.pr_reg, regs);
buf = append_elf_note(buf, "CORE", NT_PRSTATUS, &prstatus,
sizeof(prstatus));
final_note(buf);
}
#ifdef CONFIG_SMP
static atomic_t waiting_for_crash_ipi;
void crash_ipi_callback(struct pt_regs *regs)
{
int cpu = smp_processor_id();
if (cpu == crashing_cpu)
return;
if (!cpu_online(cpu))
return;
if (ppc_md.kexec_cpu_down)
ppc_md.kexec_cpu_down(1, 1);
local_irq_disable();
crash_save_this_cpu(regs, cpu);
atomic_dec(&waiting_for_crash_ipi);
kexec_smp_wait();
/* NOTREACHED */
}
static void crash_kexec_prepare_cpus(void)
{
unsigned int msecs;
atomic_set(&waiting_for_crash_ipi, num_online_cpus() - 1);
crash_send_ipi(crash_ipi_callback);
smp_wmb();
/*
* FIXME: Until we will have the way to stop other CPUSs reliabally,
* the crash CPU will send an IPI and wait for other CPUs to
* respond. If not, proceed the kexec boot even though we failed to
* capture other CPU states.
* Delay of at least 10 seconds.
*/
printk(KERN_ALERT "Sending IPI to other cpus...\n");
msecs = 10000;
while ((atomic_read(&waiting_for_crash_ipi) > 0) && (--msecs > 0)) {
barrier();
mdelay(1);
}
/* Would it be better to replace the trap vector here? */
/*
* FIXME: In case if we do not get all CPUs, one possibility: ask the
* user to do soft reset such that we get all.
* IPI handler is already set by the panic cpu initially. Therefore,
* all cpus could invoke this handler from die() and the panic CPU
* will call machine_kexec() directly from this handler to do
* kexec boot.
*/
if (atomic_read(&waiting_for_crash_ipi))
printk(KERN_ALERT "done waiting: %d cpus not responding\n",
atomic_read(&waiting_for_crash_ipi));
/* Leave the IPI callback set */
}
#else
static void crash_kexec_prepare_cpus(void)
{
/*
* move the secondarys to us so that we can copy
* the new kernel 0-0x100 safely
*
* do this if kexec in setup.c ?
*/
smp_release_cpus();
}
#endif
void default_machine_crash_shutdown(struct pt_regs *regs)
{
unsigned int irq;
/*
* This function is only called after the system
* has panicked or is otherwise in a critical state.
* The minimum amount of code to allow a kexec'd kernel
* to run successfully needs to happen here.
*
* In practice this means stopping other cpus in
* an SMP system.
* The kernel is broken so disable interrupts.
*/
local_irq_disable();
for_each_irq(irq) {
struct irq_desc *desc = irq_descp(irq);
if (desc->status & IRQ_INPROGRESS)
desc->chip->end(irq);
if (!(desc->status & IRQ_DISABLED))
desc->chip->disable(irq);
}
if (ppc_md.kexec_cpu_down)
ppc_md.kexec_cpu_down(1, 0);
/*
* Make a note of crashing cpu. Will be used in machine_kexec
* such that another IPI will not be sent.
*/
crashing_cpu = smp_processor_id();
crash_kexec_prepare_cpus();
crash_save_this_cpu(regs, crashing_cpu);
}