23 lines
915 B
Plaintext
23 lines
915 B
Plaintext
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Basic instructions to use ctracer:
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1. build the kernel with CONFIG_DEBUG_INFO=y, i.e. gcc -g, that will
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insert the DWARF info needed by all the pahole tools, ctracer, etc.
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2. Run ctracer to generate the kprobes module:
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[acme@newtoy linux-2.6]$ ctracer fs/ext3/built-in.o inode > module.c
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3. build module.c following the instructions in Documentation/kprobes.txt
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4. load the resulting module, that will, as of now, just use printk, in the
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future will use relayfs like blktrace does, but for now you'll get:
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[root@qemu ~]# dmesg | tail
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[32178.442056] ext3_init_block_alloc_info: inode=cf5fecdc
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[32178.455011] ext3_new_blocks: inode=cf5fecdc
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[32178.480993] ext3_discard_reservation: inode=cf5fecdc
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[32200.609075] ext3_free_blocks: inode=cf5fecdc
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[32200.620973] ext3_discard_reservation: inode=cf5fecdc
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[32200.624582] ext3_discard_reservation: inode=cf5fecdc
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[32368.284849] ext3_free_blocks: inode=cf6e15ec
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