diff options
| author | Thomas Gleixner <tglx@linutronix.de> | 2017-09-13 23:29:53 +0200 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2017-09-25 20:52:02 +0200 |
| commit | 2cffad7bad83157f89332872015f4305d2ac09ac (patch) | |
| tree | 4252f822312b28615986a5caa94c988b2080d4c6 /arch/x86/include/asm/apic.h | |
| parent | 464d12309e1b5829597793db551ae8ecaecf4036 (diff) | |
x86/irq: Simplify hotplug vector accounting
Before a CPU is taken offline the number of active interrupt vectors on the
outgoing CPU and the number of vectors which are available on the other
online CPUs are counted and compared. If the active vectors are more than
the available vectors on the other CPUs then the CPU hot-unplug operation
is aborted. This again uses loop based search and is inaccurate.
The bitmap matrix allocator has accurate accounting information and can
tell exactly whether the vector space is sufficient or not.
Emit a message when the number of globaly reserved (unallocated) vectors is
larger than the number of available vectors after offlining a CPU because
after that point request_irq() might fail.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juergen Gross <jgross@suse.com>
Tested-by: Yu Chen <yu.c.chen@intel.com>
Acked-by: Juergen Gross <jgross@suse.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Alok Kataria <akataria@vmware.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Rui Zhang <rui.zhang@intel.com>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Len Brown <lenb@kernel.org>
Link: https://lkml.kernel.org/r/20170913213156.351193962@linutronix.de
Diffstat (limited to 'arch/x86/include/asm/apic.h')
| -rw-r--r-- | arch/x86/include/asm/apic.h | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/arch/x86/include/asm/apic.h b/arch/x86/include/asm/apic.h index 7a8651921ed5..a9e57f08bfa6 100644 --- a/arch/x86/include/asm/apic.h +++ b/arch/x86/include/asm/apic.h @@ -386,6 +386,7 @@ extern struct apic *__apicdrivers[], *__apicdrivers_end[]; */ #ifdef CONFIG_SMP extern int wakeup_secondary_cpu_via_nmi(int apicid, unsigned long start_eip); +extern int lapic_can_unplug_cpu(void); #endif #ifdef CONFIG_X86_LOCAL_APIC |