linux/arch/riscv
Linus Torvalds 970b766cfd Andy Lutomirski approached me to tell me that the syscall_get_arguments()
implementation in x86 was horrible and gcc  certainly gets it wrong. He
 said that since the tracepoints only pass in 0 and 6 for i and n repectively,
 it should be optimized for that case. Inspecting the kernel, I discovered
 that all users pass in 0 for i and only one file passing in something other
 than 6 for the number of arguments. That code happens to be my own code used
 for the special syscall tracing. That can easily be converted to just
 using 0 and 6 as well, and only copying what is needed. Which is probably
 the faster path anyway for that case.
 
 Along the way, a couple of real fixes came from this as the
 syscall_get_arguments() function was incorrect for csky and riscv.
 
 x86 has been optimized to for the new interface that removes the variable
 number of arguments, but the other architectures could still use some
 loving and take more advantage of the simpler interface.
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Merge tag 'trace-5.1-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull syscall-get-arguments cleanup and fixes from Steven Rostedt:
 "Andy Lutomirski approached me to tell me that the
  syscall_get_arguments() implementation in x86 was horrible and gcc
  certainly gets it wrong.

  He said that since the tracepoints only pass in 0 and 6 for i and n
  repectively, it should be optimized for that case. Inspecting the
  kernel, I discovered that all users pass in 0 for i and only one file
  passing in something other than 6 for the number of arguments. That
  code happens to be my own code used for the special syscall tracing.

  That can easily be converted to just using 0 and 6 as well, and only
  copying what is needed. Which is probably the faster path anyway for
  that case.

  Along the way, a couple of real fixes came from this as the
  syscall_get_arguments() function was incorrect for csky and riscv.

  x86 has been optimized to for the new interface that removes the
  variable number of arguments, but the other architectures could still
  use some loving and take more advantage of the simpler interface"

* tag 'trace-5.1-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  syscalls: Remove start and number from syscall_set_arguments() args
  syscalls: Remove start and number from syscall_get_arguments() args
  csky: Fix syscall_get_arguments() and syscall_set_arguments()
  riscv: Fix syscall_get_arguments() and syscall_set_arguments()
  tracing/syscalls: Pass in hardcoded 6 into syscall_get_arguments()
  ptrace: Remove maxargs from task_current_syscall()
2019-04-05 13:15:57 -10:00
..
boot RISC-V: Build flat and compressed kernel images 2018-11-20 05:19:09 -08:00
configs RISC-V: defconfig: Add CRYPTO_DEV_VIRTIO=y 2019-01-23 14:09:01 -08:00
include Andy Lutomirski approached me to tell me that the syscall_get_arguments() 2019-04-05 13:15:57 -10:00
kernel RISC-V: Use IS_ENABLED(CONFIG_CMODEL_MEDLOW) 2019-03-28 23:18:51 -07:00
lib RISC-V: lib: minor asm cleanup 2018-12-21 08:17:02 -08:00
mm RISC-V: Always compile mm/init.c with cmodel=medany and notrace 2019-03-26 18:25:06 -07:00
net bpf, riscv: add BPF JIT for RV64G 2019-02-05 16:56:10 +01:00
Kconfig DMA mapping updates for 5.1 2019-03-10 11:54:48 -07:00
Kconfig.debug RISC-V: Remove EARLY_PRINTK support 2018-12-17 10:23:46 -08:00
Makefile bpf, riscv: add BPF JIT for RV64G 2019-02-05 16:56:10 +01:00