[PATCH v3 00/22] Reduce the scope of 'nr_irqs'

[Bart Van Assche <bvanassche@acm.org>]

Hi Thomas,

In addition to the global 'nr_irqs' variable, there are plenty of local
variables with the same name. This makes reviewing kernel patches and
auditing kernel source code harder than necessary. Hence this patch series
that reduces the scope of the global 'nr_irqs' variable to file scope and
that introduces functions for retrieving and setting the value of this
variable.

Accesses of the global variable 'nr_irqs' have been identified with
Coccinelle.

Please consider this patch series for the next merge window.

Thanks,

Bart.

Changes compared to v2:
 - Changed "This patch prepares" into "Prepare" in the several patch
   descriptions.
 - Changed the type of 'nr_irqs' from 'int' into 'unsigned int'.

Changes compared to v1:
 - Renamed the accessor functions: number_of_interrupts() has been renamed into
   irq_get_nr_irqs() and set_number_of_interrupts() has been renamed into
   set_number_of_interrupts().
 - Made the description of patch 01 more detailed. It is now explained in
   detail why it is useful to introduce accessor functions for 'nr_irqs'.
 - Cache the irq_get_nr_irqs() return value if it is used as a loop upper bound
   or inside a loop body instead of relying on CSE (common subexpression
   elimination) by the compiler.
 - Changed the return type of the accessor functions from 'int' into
   'unsigned int'.
 - Split the hamradio patch into two patches - one patch per driver.

Bart Van Assche (22):
  genirq: Introduce irq_get_nr_irqs() and irq_set_nr_irqs()
  ARM: Switch to irq_get_nr_irqs() / irq_set_nr_irqs()
  LoongArch: Switch to irq_set_nr_irqs()
  powerpc/cell: Switch to irq_get_nr_irqs()
  s390/irq: Switch to irq_get_nr_irqs()
  x86/acpi: Switch to irq_get_nr_irqs() and irq_set_nr_irqs()
  hpet: Switch to irq_get_nr_irqs()
  net: 3com: 3c59x: Switch to irq_get_nr_irqs()
  net: hamradio: baycom_ser_fdx: Switch to irq_get_nr_irqs()
  net: hamradio: scc: Switch to irq_get_nr_irqs()
  scsi: aha152x: Switch to irq_get_nr_irqs()
  serial: core: Switch to irq_get_nr_irqs()
  serial: 8250: Switch to irq_get_nr_irqs()
  serial: amba-pl010: Switch to irq_get_nr_irqs()
  serial: amba-pl011: Switch to irq_get_nr_irqs()
  serial: cpm_uart: Switch to irq_get_nr_irqs()
  serial: ucc_uart: Switch to irq_get_nr_irqs()
  sh: intc: Switch to irq_get_nr_irqs()
  xen/events: Switch to irq_get_nr_irqs()
  fs/procfs: Switch to irq_get_nr_irqs()
  genirq: Switch to irq_get_nr_irqs()
  genirq: Unexport nr_irqs

 arch/arm/kernel/irq.c                  |  5 ++--
 arch/loongarch/kernel/irq.c            |  4 +--
 arch/powerpc/platforms/cell/axon_msi.c |  2 +-
 arch/s390/kernel/irq.c                 |  2 +-
 arch/x86/kernel/acpi/boot.c            |  6 +++--
 arch/x86/kernel/apic/vector.c          |  8 +++---
 drivers/char/hpet.c                    |  1 +
 drivers/net/ethernet/3com/3c59x.c      |  2 +-
 drivers/net/hamradio/baycom_ser_fdx.c  |  1 +
 drivers/net/hamradio/scc.c             |  4 ++-
 drivers/scsi/aha152x.c                 |  2 +-
 drivers/sh/intc/virq-debugfs.c         |  1 +
 drivers/tty/serial/8250/8250_port.c    |  2 +-
 drivers/tty/serial/amba-pl010.c        |  2 +-
 drivers/tty/serial/amba-pl011.c        |  2 +-
 drivers/tty/serial/cpm_uart.c          |  2 +-
 drivers/tty/serial/serial_core.c       |  2 +-
 drivers/tty/serial/ucc_uart.c          |  2 +-
 drivers/xen/events/events_base.c       |  2 +-
 fs/proc/interrupts.c                   |  4 +--
 fs/proc/stat.c                         |  4 +--
 include/linux/irqnr.h                  | 36 +++++++++++++++-----------
 kernel/irq/irqdesc.c                   | 26 +++++++++++++++++--
 kernel/irq/irqdomain.c                 |  2 +-
 kernel/irq/proc.c                      |  3 ++-
 25 files changed, 81 insertions(+), 46 deletions(-)