Re: Packet socket: mmapped IO

cone wrote:
When configuring the kernel, the configuration help suggests disabling the
option "Packet socket: mmapped IO". Is there any reason for choosing the slower
implementation without mmap?


IIRC there were alignment issues for memory mapped boards. I read about this in the documentation of earlier version of 3c59x boards.
But I think it is solved (for those boards at least).

Ciao
Giovanni
--
A computer is like an air conditioner,
it stops working when you open Windows.
Registered Linux user #337974 <http://counter.li.org/>
.

Relevant Pages

  • Re: memory management related system calls
    ... > Actually recent malloc implementions are mmap based IIRC. ... > essentially obsolete. ... brk() is still used for small allocations. ...
    (comp.os.linux.development.system)
  • Re: [PATCH 3/5] parisc: use new macros for .data.init_task.
    ... IIRC, gcc on hppa is not able to provide an alignment>= 8k, which is ... why we have done the 16k alignment inside the linker script. ...
    (Linux-Kernel)
  • Re: [PATCH/RFC] Shared page tables
    ... mmap() a private, anonymous region in its place. ... I imagine the above gets even more interesting if the offset or length of the ... unmapped region is not a multiple of the 2MB alignment. ...
    (Linux-Kernel)
  • Trapping writes to mmapd memory.
    ... (given the constaints of mmap alignment). ... I know about mprotect() + trapping SIGSEGV and have been able to get that to work, but am looking for a more elegant way to do this within a library because, AFAIK: ... I need mmap and the memory it returns to function as efficiently as, say, malloc, but am not neccessarily opposed to a file backed SHARED/NON-ANON mapping if there is someway to accomplish what I want with that also. ...
    (comp.os.linux.development.system)
  • Special handling of sysfs device resource files?
    ... I've modified it to map the ... In all cases, the open and mmap ... the alignment of mmap vs. the alignment of the BAR. ...
    (Linux-Kernel)