PJ40912: UPDATE LOCKC() CODE TO IMPROVE PERFORMANCE.

APAR status

• Closed as program error.

Error description

• See Problem Summary.
  

Local fix

• na
  

Problem summary

• APAR NUMBER:  PJ40912
  PRODUCT:  z/TPF
  FUNCTIONAL AREA:  INTER-ISTREAM COMMUNICATION
  SHIPPED IN PUT:  10
  
  ABSTRACT:
  The C function lockc() needs to be updated to improve
  performance.
  
  PACKAGE CONTENTS:
  Source Segments:
  (C) base/rt/clockc.asm
  
  Object Only Binaries:
  None.
  
  Configuration Independent Binaries:
  None.
  
  Support Files:
  None.
  
  OTHER BINARIES TO BUILD: YES
  (C) <sys>/obj/clockc.o
  (C) <sys>/stdlib/libCTAL.so
  (C) <sys>/stdload/CTAL.so
  
  COMMENTS:
  The LOCKC macro was updated to have a SYS=YES optional
  parameter that would use a CLI (compare logical immediate)
  instruction loop to check for a lock being held rather than a
  CS (Compare and Swap) instruction loop. This improved locking
  performance because checking the lock became read of the
  lockword's storage cache line rather than the repeated write of
  the line as done by CS. To improve the performance of the C
  function lockc(), a one-line change can be made in clockc.asm
  to use LOCKC with the SYS=YES parameter
  

Problem conclusion

• SOLUTION:
  The lockc macro call in clockc.asm was updated to use the
  SYS=YES parameter.
  
  COREQS: NO
  None.
  
  MIGRATION CONSIDERATIONS: NO
  None.
  
  BUILD COMMANDS AND INSTRUCTIONS: YES
  #maketpf commands for linux
  maketpf -f CTAL clockc.o
  maketpf CTAL link TPF_VERIFY_LINK_REFS=NO
  maketpf CTAL link
  
  UPDATED INFORMATION UNITS: NO
  None.
  
  See your IBM representative if you need additional information.
  
  DOWNLOAD INSTRUCTIONS:
  http://www.ibm.com/software/htp/tpf/maint/maintztpf.html
  
  APAR URL:
  http://www.ibm.com/software/htp/tpf/ztpfmaint/put10/PJ40912.htm
  

Temporary fix

Comments

APAR Information

• APAR is sysrouted FROM one or more of the following:

• APAR is sysrouted TO one or more of the following:

Fix information

• Fixed component name

  Z/TPF

• Fixed component ID

  5748T1501

Applicable component levels

• R110 PSY

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