• Robert Richter's avatar
    oprofile, x86: Reimplement nmi timer mode using perf event · dcfce4a0
    Robert Richter authored
    The legacy x86 nmi watchdog code was removed with the implementation
    of the perf based nmi watchdog. This broke Oprofile's nmi timer
    mode. To run nmi timer mode we relied on a continuous ticking nmi
    source which the nmi watchdog provided. The nmi tick was no longer
    available and current watchdog can not be used anymore since it runs
    with very long periods in the range of seconds. This patch
    reimplements the nmi timer mode using a perf counter nmi source.
    
    V2:
    * removing pr_info()
    * fix undefined reference to `__udivdi3' for 32 bit build
    * fix section mismatch of .cpuinit.data:nmi_timer_cpu_nb
    * removed nmi timer setup in arch/x86
    * implemented function stubs for op_nmi_init/exit()
    * made code more readable in oprofile_init()
    
    V3:
    * fix architectural initialization in oprofile_init()
    * fix CONFIG_OPROFILE_NMI_TIMER dependencies
    Acked-by: default avatarPeter Zijlstra <a.p.zijlstra@chello.nl>
    Signed-off-by: default avatarRobert Richter <robert.richter@amd.com>
    dcfce4a0
core.c 163 KB