On Thu, Sep 01, 2022 at 03:34:49PM -0700, Dave Hansen wrote:
On 9/1/22 15:20, Jarkko Sakkinen wrote:
+kr:sgx_alloc_epc_page /(uint64)retval >= (uint64)(-4095)/ {
printf("sgx_alloc_epc_page: retval=%d\n", (int64)retval);+}
+kr:sgx_encl_page_alloc /(uint64)retval >= (uint64)(-4095)/ {
printf("sgx_encl_page_alloc: retval=%d\n", (int64)retval);+}
I guess this doesn't _hurt_, but it's also not exactly the easiest way to get this done. You need a whole bpf toolchain. You could also just do:
perf probe 'sgx_encl_page_alloc%return $retval'
Even *that* can be replicated in a few scant lines of shell code echoing into /sys/kernel/debug/tracing.
Thanks, I have not used perf that much. What if I replace this with a shell script using perf? How do you use that for two kretprobes?
The manpage is pretty good.
But, I'd proably be doing something along these lines:
perf probe 'sgx_encl_page_alloc%return ret=$retval' perf record -e probe:sgx_encl_page_alloc -aR \ --filter='ret >= 0xwhatever' sleep 1 perf script
There are probably shorter ways to do it, but I'm pretty sure that works.
Thanks, will give it a shot.
BR, Jarkko