• Frederic Weisbecker's avatar
    hw-breakpoints: Get the number of available registers on boot dynamically · feef47d0
    Frederic Weisbecker authored
    The breakpoint generic layer assumes that archs always know in advance
    the static number of address registers available to host breakpoints
    through the HBP_NUM macro.
    
    However this is not true for every archs. For example Arm needs to get
    this information dynamically to handle the compatiblity between
    different versions.
    
    To solve this, this patch proposes to drop the static HBP_NUM macro
    and let the arch provide the number of available slots through a
    new hw_breakpoint_slots() function. For archs that have
    CONFIG_HAVE_MIXED_BREAKPOINTS_REGS selected, it will be called once
    as the number of registers fits for instruction and data breakpoints
    together.
    For the others it will be called first to get the number of
    instruction breakpoint registers and another time to get the
    data breakpoint registers, the targeted type is given as a
    parameter of hw_breakpoint_slots().
    Reported-by: default avatarWill Deacon <will.deacon@arm.com>
    Signed-off-by: default avatarFrederic Weisbecker <fweisbec@gmail.com>
    Acked-by: default avatarPaul Mundt <lethal@linux-sh.org>
    Cc: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
    Cc: K. Prasad <prasad@linux.vnet.ibm.com>
    Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
    Cc: Paul Mackerras <paulus@samba.org>
    Cc: Jason Wessel <jason.wessel@windriver.com>
    Cc: Ingo Molnar <mingo@elte.hu>
    feef47d0
trace_ksym.c 11.9 KB