| 1 | /* |
| 2 | * Copyright 2004 Sun Microsystems, Inc. All rights reserved. |
| 3 | * Use is subject to license terms. |
| 4 | */ |
| 5 | #pragma ident "@(#)README.lockstep 1.1 05/07/29 SMI" |
| 6 | |
| 7 | ## |
| 8 | ## Lockstep Execution (lockstep) |
| 9 | ## |
| 10 | ## This explains how to enable and use the lockstep feature |
| 11 | ## |
| 12 | |
| 13 | [-] Enabling this Features: |
| 14 | |
| 15 | See README.debug_hook for full details on how to enable this feature. |
| 16 | |
| 17 | [-] Lockstep Execution: |
| 18 | |
| 19 | Description: |
| 20 | This feature allows you to run 2 simulators in lockstep. This could be |
| 21 | used to run 2 copies of legion (one in 'master' mode and the other in |
| 22 | 'slave' mode) or to run legion in lockstep with another simulator or tool |
| 23 | (assuming the other simulator/tool implements the 'slave' side of the |
| 24 | lockstep feature). |
| 25 | |
| 26 | Each legion needs to have either a 'master' or a 'slave' lockstep |
| 27 | directive added in order to be able to run them in lockstep. |
| 28 | They must both be running on the same system and must have |
| 29 | been started by the same user-id. |
| 30 | |
| 31 | Format: |
| 32 | * debug_hook [lockstep] [mode] [start] |
| 33 | * |
| 34 | * [lockstep] - we've already parsed this. That's how we got here. |
| 35 | * [mode] - master or slave |
| 36 | * master writes its data to shm region and waits for |
| 37 | * slave to compare. Dump any mismatches when simulators |
| 38 | * fall out of lockstep. |
| 39 | * [start] - optional, when supplied we enter into lockstep mode |
| 40 | * from this instn count onwards |
| 41 | * |
| 42 | |
| 43 | Examples: |
| 44 | Each legion needs to have either a 'master' or a 'slave' lockstep |
| 45 | directive added to it's config file. Examples of both master and |
| 46 | slave formats are below: |
| 47 | |
| 48 | processor "niagara" { |
| 49 | clkfreq 5000000 ; |
| 50 | cores 1; |
| 51 | vthreads 1; |
| 52 | nglobals 4; |
| 53 | nwins 8; |
| 54 | rstv 0xfff0000020; |
| 55 | maxtl 7; |
| 56 | // Lockstep examples: |
| 57 | // debug_hook lockstep master; |
| 58 | // debug_hook lockstep slave; |
| 59 | // debug_hook lockstep master 0x10; |
| 60 | // debug_hook lockstep slave 0x10; |
| 61 | } |
| 62 | |
| 63 | Viewing Data: |
| 64 | There is no data to be viewed until the simulators fall out of lockstep |
| 65 | with each other. If this does happen, the instn and previous instn on |
| 66 | both simualtors will be dumped with the complete register dump of both |
| 67 | master and slave similators showing where the mismatch is. |
| 68 | |
| 69 | Modifying Source: |
| 70 | The source for the coverage feature is contained in |
| 71 | src/procs/sunsparc/debug/lockstep.c |
| 72 | |