cvs commit: src/sys/dev/em if_em.c if_em.h if_em_osdep.h

[John Polstra]

jdp         2003/08/01 10:33:59 PDT

  FreeBSD src repository

  Modified files:
    sys/dev/em           if_em.c if_em.h if_em_osdep.h 
  Log:
  Add facilities for tuning the "em" driver's interrupt delays without
  recompiling the driver.  See the comments near the top of "if_em.h"
  for descriptions of these delays.  Four new loader tunables control
  the system-wide default values:
  
      hw.em.tx_int_delay
      hw.em.rx_int_delay
      hw.em.tx_abs_int_delay
      hw.em.rx_abs_int_delay
  
  The tunables are specified in microseconds.  The valid range is
  0-67108 usec., and 0 means that the timer is disabled.
  
  There are also four new sysctls (actually, a set of four for each
  "em" device in the system) to query and change the interrupt delays
  after the system is up:
  
      hw.em0.tx_int_delay
      hw.em0.rx_int_delay
      hw.em0.tx_abs_int_delay (not present for 82542/3/4 adapters)
      hw.em0.rx_abs_int_delay (not present for 82542/3/4 adapters)
  
  It seems to be OK to change these values even while the adapter is
  passing traffic.
  
  Approved by:    Prafulla Deuskar <pdeuskar at FreeBSD.ORG>
  MFC after:      4 weeks
  
  Revision  Changes    Path
  1.28      +108 -9    src/sys/dev/em/if_em.c
  1.19      +11 -4     src/sys/dev/em/if_em.h
  1.12      +28 -30    src/sys/dev/em/if_em_osdep.h