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make use of gcc 9's "asm inline()"

From:  Rasmus Villemoes <linux-AT-rasmusvillemoes.dk>
To:  x86-AT-kernel.org, linux-kernel-AT-vger.kernel.org
Subject:  [RFC PATCH 0/5] make use of gcc 9's "asm inline()"
Date:  Thu, 29 Aug 2019 10:32:28 +0200
Message-ID:  <20190829083233.24162-1-linux@rasmusvillemoes.dk>
Cc:  Ingo Molnar <mingo-AT-redhat.com>, Thomas Gleixner <tglx-AT-linutronix.de>, "H. Peter Anvin" <hpa-AT-zytor.com>, Nadav Amit <namit-AT-vmware.com>, Linus Torvalds <torvalds-AT-linux-foundation.org>, Miguel Ojeda <miguel.ojeda.sandonis-AT-gmail.com>, ndesaulniers-AT-google.com, Rasmus Villemoes <linux-AT-rasmusvillemoes.dk>
Archive-link:  Article

gcc 9 provides a way to override the otherwise crude heuristic that
gcc uses to estimate the size of the code represented by an asm()
statement. From the gcc docs

  If you use 'asm inline' instead of just 'asm', then for inlining
  purposes the size of the asm is taken as the minimum size, ignoring
  how many instructions GCC thinks it is.

For compatibility with older compilers, we obviously want a

  #if new enough
  #define asm_inline asm inline
  #else
  #define asm_inline asm
  #endif

But since we #define the identifier inline to attach some attributes,
we have to use the alternate spelling __inline__ of that
keyword. Unfortunately, we also currently #define that one (to
inline), so we first have to get rid of all (mis)uses of
__inline__. Hence the huge diffstat. I think patch 1 should be
regenerated and applied just before -rc1.

There are a few remaining users of __inline__, in particular in uapi
headers, which I'm not sure what to do about (kernel-side users of
those will get slightly different semantics since we no longer
automatically attach the __attribute__((__gnu_inline__)) etc.). So RFC.

The two x86 changes cause smaller code gen differences than I'd
expect, but I think we do want the asm_inline thing available sooner
or later, so this is just to get the ball rolling.

Rasmus Villemoes (5):
  treewide: replace __inline__ by inline
  compiler_types.h: don't #define __inline__
  compiler-gcc.h: add asm_inline definition
  x86: alternative.h: use asm_inline for all alternative variants
  x86: bug.h: use asm_inline in _BUG_FLAGS definitions

 arch/alpha/include/asm/atomic.h               | 12 +++---
 arch/alpha/include/asm/bitops.h               |  6 +--
 arch/alpha/include/asm/dma.h                  | 22 +++++-----
 arch/alpha/include/asm/floppy.h               |  2 +-
 arch/alpha/include/asm/irq.h                  |  2 +-
 arch/alpha/include/asm/local.h                |  4 +-
 arch/alpha/include/asm/smp.h                  |  2 +-
 .../arm/mach-iop32x/include/mach/uncompress.h |  2 +-
 .../arm/mach-iop33x/include/mach/uncompress.h |  2 +-
 .../arm/mach-ixp4xx/include/mach/uncompress.h |  2 +-
 arch/ia64/hp/common/sba_iommu.c               |  2 +-
 arch/ia64/hp/sim/simeth.c                     |  2 +-
 arch/ia64/include/asm/atomic.h                |  8 ++--
 arch/ia64/include/asm/bitops.h                | 34 ++++++++--------
 arch/ia64/include/asm/delay.h                 | 14 +++----
 arch/ia64/include/asm/irq.h                   |  2 +-
 arch/ia64/include/asm/page.h                  |  2 +-
 arch/ia64/include/asm/sn/leds.h               |  2 +-
 arch/ia64/include/asm/uaccess.h               |  4 +-
 arch/ia64/oprofile/backtrace.c                |  4 +-
 arch/m68k/include/asm/blinken.h               |  2 +-
 arch/m68k/include/asm/checksum.h              |  2 +-
 arch/m68k/include/asm/dma.h                   | 32 +++++++--------
 arch/m68k/include/asm/floppy.h                |  8 ++--
 arch/m68k/include/asm/nettel.h                |  8 ++--
 arch/m68k/mac/iop.c                           | 14 +++----
 arch/mips/include/asm/atomic.h                | 16 ++++----
 arch/mips/include/asm/checksum.h              |  2 +-
 arch/mips/include/asm/dma.h                   | 20 +++++-----
 arch/mips/include/asm/jazz.h                  |  2 +-
 arch/mips/include/asm/local.h                 |  4 +-
 arch/mips/include/asm/string.h                |  8 ++--
 arch/mips/kernel/binfmt_elfn32.c              |  2 +-
 arch/nds32/include/asm/swab.h                 |  4 +-
 arch/parisc/include/asm/atomic.h              | 20 +++++-----
 arch/parisc/include/asm/bitops.h              | 18 ++++-----
 arch/parisc/include/asm/checksum.h            |  4 +-
 arch/parisc/include/asm/compat.h              |  2 +-
 arch/parisc/include/asm/delay.h               |  2 +-
 arch/parisc/include/asm/dma.h                 | 20 +++++-----
 arch/parisc/include/asm/ide.h                 |  8 ++--
 arch/parisc/include/asm/irq.h                 |  2 +-
 arch/parisc/include/asm/spinlock.h            | 12 +++---
 arch/powerpc/include/asm/atomic.h             | 40 +++++++++----------
 arch/powerpc/include/asm/bitops.h             | 28 ++++++-------
 arch/powerpc/include/asm/dma.h                | 20 +++++-----
 arch/powerpc/include/asm/edac.h               |  2 +-
 arch/powerpc/include/asm/irq.h                |  2 +-
 arch/powerpc/include/asm/local.h              | 14 +++----
 arch/sh/include/asm/pgtable_64.h              |  2 +-
 arch/sh/include/asm/processor_32.h            |  4 +-
 arch/sh/include/cpu-sh3/cpu/dac.h             |  6 +--
 arch/x86/include/asm/alternative.h            | 14 +++----
 arch/x86/include/asm/bug.h                    |  4 +-
 arch/x86/um/asm/checksum.h                    |  4 +-
 arch/x86/um/asm/checksum_32.h                 |  4 +-
 arch/xtensa/include/asm/checksum.h            | 14 +++----
 arch/xtensa/include/asm/cmpxchg.h             |  4 +-
 arch/xtensa/include/asm/irq.h                 |  2 +-
 block/partitions/amiga.c                      |  2 +-
 drivers/atm/he.c                              |  6 +--
 drivers/atm/idt77252.c                        |  6 +--
 drivers/gpu/drm/mga/mga_drv.h                 |  2 +-
 drivers/gpu/drm/mga/mga_state.c               | 14 +++----
 drivers/gpu/drm/r128/r128_drv.h               |  2 +-
 drivers/gpu/drm/r128/r128_state.c             | 14 +++----
 drivers/gpu/drm/via/via_irq.c                 |  2 +-
 drivers/gpu/drm/via/via_verifier.c            | 30 +++++++-------
 drivers/media/pci/ivtv/ivtv-ioctl.c           |  2 +-
 drivers/net/ethernet/sun/sungem.c             |  8 ++--
 drivers/net/ethernet/sun/sunhme.c             |  6 +--
 drivers/net/hamradio/baycom_ser_fdx.c         |  2 +-
 drivers/net/wan/lapbether.c                   |  2 +-
 drivers/net/wan/n2.c                          |  4 +-
 drivers/parisc/led.c                          |  4 +-
 drivers/parisc/sba_iommu.c                    |  2 +-
 drivers/parport/parport_gsc.h                 |  4 +-
 drivers/scsi/lpfc/lpfc_scsi.c                 |  2 +-
 drivers/scsi/pcmcia/sym53c500_cs.c            |  4 +-
 drivers/scsi/qla2xxx/qla_inline.h             |  2 +-
 drivers/scsi/qla2xxx/qla_os.c                 |  2 +-
 drivers/tty/amiserial.c                       |  2 +-
 drivers/tty/serial/ip22zilog.c                |  2 +-
 drivers/tty/serial/sunsab.c                   |  4 +-
 drivers/tty/serial/sunzilog.c                 |  2 +-
 drivers/video/fbdev/core/fbcon.c              | 20 +++++-----
 drivers/video/fbdev/ffb.c                     |  2 +-
 drivers/video/fbdev/intelfb/intelfbdrv.c      |  8 ++--
 drivers/video/fbdev/intelfb/intelfbhw.c       |  2 +-
 drivers/w1/masters/matrox_w1.c                |  4 +-
 fs/coda/coda_linux.h                          |  6 +--
 fs/freevxfs/vxfs_inode.c                      |  2 +-
 fs/nfsd/nfsfh.h                               |  4 +-
 include/acpi/platform/acgcc.h                 |  2 +-
 include/asm-generic/ide_iops.h                |  8 ++--
 include/linux/atalk.h                         |  4 +-
 include/linux/compiler-gcc.h                  |  4 ++
 include/linux/compiler_types.h                |  5 ++-
 include/linux/hdlc.h                          |  4 +-
 include/linux/inetdevice.h                    |  6 +--
 include/linux/parport.h                       |  4 +-
 include/linux/parport_pc.h                    | 22 +++++-----
 include/net/ax25.h                            |  2 +-
 include/net/checksum.h                        |  2 +-
 include/net/dn_nsp.h                          | 16 ++++----
 include/net/ip.h                              |  2 +-
 include/net/ip6_checksum.h                    |  2 +-
 include/net/ipx.h                             | 10 ++---
 include/net/llc_c_ev.h                        |  4 +-
 include/net/llc_conn.h                        |  4 +-
 include/net/llc_s_ev.h                        |  2 +-
 include/net/netrom.h                          |  8 ++--
 include/net/scm.h                             | 14 +++----
 include/net/udplite.h                         |  2 +-
 include/net/x25.h                             |  8 ++--
 include/net/xfrm.h                            | 18 ++++-----
 include/video/newport.h                       | 12 +++---
 net/appletalk/atalk_proc.c                    |  4 +-
 net/appletalk/ddp.c                           |  2 +-
 net/core/neighbour.c                          |  2 +-
 net/core/scm.c                                |  2 +-
 net/decnet/dn_nsp_in.c                        |  2 +-
 net/decnet/dn_nsp_out.c                       |  2 +-
 net/decnet/dn_route.c                         |  2 +-
 net/decnet/dn_table.c                         |  4 +-
 net/ipv6/af_inet6.c                           |  2 +-
 net/ipv6/icmp.c                               |  4 +-
 net/ipv6/udp.c                                |  2 +-
 net/lapb/lapb_iface.c                         |  4 +-
 net/llc/llc_input.c                           |  2 +-
 sound/sparc/amd7930.c                         |  6 +--
 131 files changed, 449 insertions(+), 442 deletions(-)

-- 
2.20.1



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