• Paul Mundt's avatar
    sh: Trivial trace_mark() instrumentation for core events. · 3d58695e
    Paul Mundt authored
    This implements a few trace points across events that are deemed
    interesting. This implements a number of trace points:
    
    	- The page fault handler / TLB miss
    	- IPC calls
    	- Kernel thread creation
    
    The original LTTng patch had the slow-path instrumented, which
    fails to account for the vast majority of events. In general
    placing this in the fast-path is not a huge performance hit, as
    we don't take page faults for kernel addresses.
    
    The other bits of interest are some of the other trap handlers, as
    well as the syscall entry/exit (which is better off being handled
    through the tracehook API). Most of the other trap handlers are corner
    cases where alternate means of notification exist, so there is little
    value in placing extra trace points in these locations.
    
    Based on top of the points provided both by the LTTng instrumentation
    patch as well as the patch shipping in the ST-Linux tree, albeit in a
    stripped down form.
    Signed-off-by: default avatarPaul Mundt <lethal@linux-sh.org>
    3d58695e
sys_sh.c 6.4 KB