From mboxrd@z Thu Jan 1 00:00:00 1970 From: linkerndbg@gmail.com (linkerndbg) Date: Sun, 5 Jun 2011 16:38:03 +0200 Subject: reading a core's current task from memory Message-ID: To: kernelnewbies@lists.kernelnewbies.org List-Id: kernelnewbies.lists.kernelnewbies.org Hi dear list members, I'm maintaining a Linux kernel debugger through jtag that has been doing quite well on unicore/SH4 systems so far, now I'd like to support ARM/SMP systems and do some improvements: I'm looking for a simple way to know which is the current task executing on one each core by accessing memory from jtag. Knowing a core's current when it is running kernel core is easy as the sp registers gives direct access to the current thread_info, now suppose a core is running a usermode code page, then sp and pc are virtual memory. through the jtag interface I can access any symbol which offset I know from the vmlinux symbol table, and any field which offset is not dependent of the configure options for a given kernel version. Sadly I can't easily access the per_cpu runqueues and the rq->curr field this way. I'd be grateful for any suggestion as of how to do ! many thanks, M.