diff options
| author | Aaron Tomlin <atomlin@redhat.com> | 2014-06-23 13:22:05 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2014-06-23 16:47:44 -0700 |
| commit | f3aca3d09525f87731ba6b892c9b010570bc54b4 (patch) | |
| tree | 80c80be186f7bac74cb548444562ae6890938d83 /arch/sparc/kernel | |
| parent | 88e15ce402c58f41037752da092683e90826742a (diff) | |
| download | linux-f3aca3d09525f87731ba6b892c9b010570bc54b4.tar.gz linux-f3aca3d09525f87731ba6b892c9b010570bc54b4.tar.bz2 linux-f3aca3d09525f87731ba6b892c9b010570bc54b4.zip | |
nmi: provide the option to issue an NMI back trace to every cpu but current
Sometimes it is preferred not to use the trigger_all_cpu_backtrace()
routine when one wants to avoid capturing a back trace for current. For
instance if one was previously captured recently.
This patch provides a new routine namely
trigger_allbutself_cpu_backtrace() which offers the flexibility to issue
an NMI to every cpu but current and capture a back trace accordingly.
Patch x86 and sparc to support new routine.
[dzickus@redhat.com: add stub in #else clause]
[dzickus@redhat.com: don't print message in single processor case, wrap with get/put_cpu based on Oleg's suggestion]
[sfr@canb.auug.org.au: undo C99ism]
Signed-off-by: Aaron Tomlin <atomlin@redhat.com>
Signed-off-by: Don Zickus <dzickus@redhat.com>
Acked-by: David S. Miller <davem@davemloft.net>
Cc: Mateusz Guzik <mguzik@redhat.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'arch/sparc/kernel')
| -rw-r--r-- | arch/sparc/kernel/process_64.c | 18 |
1 files changed, 12 insertions, 6 deletions
diff --git a/arch/sparc/kernel/process_64.c b/arch/sparc/kernel/process_64.c index b2988f25e230..027e09986194 100644 --- a/arch/sparc/kernel/process_64.c +++ b/arch/sparc/kernel/process_64.c @@ -239,7 +239,7 @@ static void __global_reg_poll(struct global_reg_snapshot *gp) } } -void arch_trigger_all_cpu_backtrace(void) +void arch_trigger_all_cpu_backtrace(bool include_self) { struct thread_info *tp = current_thread_info(); struct pt_regs *regs = get_irq_regs(); @@ -251,16 +251,22 @@ void arch_trigger_all_cpu_backtrace(void) spin_lock_irqsave(&global_cpu_snapshot_lock, flags); - memset(global_cpu_snapshot, 0, sizeof(global_cpu_snapshot)); - this_cpu = raw_smp_processor_id(); - __global_reg_self(tp, regs, this_cpu); + memset(global_cpu_snapshot, 0, sizeof(global_cpu_snapshot)); + + if (include_self) + __global_reg_self(tp, regs, this_cpu); smp_fetch_global_regs(); for_each_online_cpu(cpu) { - struct global_reg_snapshot *gp = &global_cpu_snapshot[cpu].reg; + struct global_reg_snapshot *gp; + + if (!include_self && cpu == this_cpu) + continue; + + gp = &global_cpu_snapshot[cpu].reg; __global_reg_poll(gp); @@ -292,7 +298,7 @@ void arch_trigger_all_cpu_backtrace(void) static void sysrq_handle_globreg(int key) { - arch_trigger_all_cpu_backtrace(); + arch_trigger_all_cpu_backtrace(true); } static struct sysrq_key_op sparc_globalreg_op = { |