Add split lock #140
Add split lock #140
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splitlock/sl_test.c
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| free(line); | ||
| fclose(fp); | ||
| if (!ret) { | ||
| printf("Fail: no split_lock_detect in /proc/cpuinfo\n"); |
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Hi Tony,
How do you think changing his message to this:
"[ERR] no split_lock_detect in /proc/cpuinfo"
"split_lock_dect [FAIL]"
Split this message into two lines: one for the detailed information and the other for the result.
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Will modify it with split_lock_dect [FAIL]
splitlock/sl_test.c
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| ret = 0; | ||
| pclose(fp); | ||
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| printf("split lock detection:%d\n", ret); |
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split_lock_dect [PASS]
split_lock_dect [FAIL]
1, I believe signal catching is necessary to determine whether this test has passed or not.
2 From my perspective, it's insufficient to rely on reading "split lock detection" in dmesg to confirm the success of this test, as it could have been previously dumped.
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Will move dmesg check to the test script. When the default of split_lock_detect is on or it is set as warn, #AC will be triggered and output to dmesg. But if it is set as fatal, kernel will send SIGBUS on user-space, no #AC message is output.
| { | ||
| printf("Caught SIGBUS/#AC due to split locked access\n"); | ||
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| exit(-1); |
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confirm the exit code -1 or 0 ?
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catch_sigbus is a void function, it is to handle user space SIGBUS which is sent by kernel. For test purpose, print out a message is enough. To mark it is abnormal, use non zero is OK, whatever it is 1 or -1.
xinzhanz
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This test app will use "lock addl" instruction to trigger #AC in hardware and kernel. Signed-off-by: Tony Zhu <[email protected]>
This test includes two test items, the first one will check cpuinfo, the second one will call split lock test to trigger an execption. Signed-off-by: Tony Zhu <[email protected]>
This document introduces what is split lock and how to test it in user mode. Signed-off-by: Tony Zhu <[email protected]>
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A split lock is any atomic operation whose operand crosses two cache lines.
Add split test including test application, test items and the document.