maxactive(NNNN) usage

[Jey Jay]

All,

Greetings,

Below is a sample script(maxactive not included).
===================================

probe kernel.function("vfs_read").call {
            printf("hai: %d\t", bytes_read)
}
probe kernel.function("vfs_read").return {
            printf("Testing.... Jay")
}

$/bin/staprun  maxactive05.ko -c 'ls'

----- probe hit report:
kernel.function("vfs_read@fs/read_write.c:353").call,
(maxactive05.stp:6:1), hits: 18, cycles: 0min/0avg/0max, from:
kernel.function("vfs_read").call, index: 0
WARNING: Skipped due to missed kretprobe/1 on
'kernel.function("vfs_read@fs/read_write.c:353").return': 3
WARNING: Number of errors: 0, skipped probes: 3

Below is a sample script(maxactive included).
=================================

probe kernel.function("vfs_read").call {
            printf("hai: %d\t", bytes_read)
}
probe kernel.function("vfs_read").return.maxactive(1000) {
            printf("Testing.... Jay")
}

$/bin/staprun  maxactive05.ko -c 'ls'

Note: It prints hai: 0 16 times.

----- probe hit report:
kernel.function("vfs_read@fs/read_write.c:353").call,
(maxactive05.stp:6:1), hits: 18, cycles: 0min/0avg/0max, from:
kernel.function("vfs_read").call, index: 0

But there is no response for .return. i.e I'm expecting
printf("Testing.... Jay") statement to be executed. Any guidance will
help me lot..

Thanks in advance.

Regards
Jeyaram