Re: [patch 00/11] Hardware Breakpoint interfaces

Ingo Molnar
2009-03-10T13:47:21Z

* prasad@linux.vnet.ibm.com <prasad@linux.vnet.ibm.com> wrote:

> Hi Ingo,

> Please find the revised set of patches that implement
> Hardware Breakpoint (or watchpoint) registers and an
> arch-specific implementation for x86/x86_64.

General structure looks good, with a good deal of details
that need to be addressed.

Firstly, as far as i can see this should work on 32-bit too,
correct?

Secondly, what about other architectures - will they build just
fine without any arch level glue code? kernel/hw_breakpoint.o
get build unconditionally - without any benefit to non-x86 code.
Perhaps an ARCH_HAS_HW_BREAKPOINTS Kconfig method would be
useful to add.

There's also a number of (small) style issues.
kernel/hw_breakpoint.c and other new .c files dont comply to the
customary comment style of:

/*
* Comment .....
* ...... goes here:
*/

also, the #include files section style should match that of
arch/x86/mm/fault.c - it's a conflict-avoidance style.

also, things like this:

static struct notifier_block hw_breakpoint_exceptions_nb = {
.notifier_call = hw_breakpoint_exceptions_notify,
.priority = 0x7fffffff /* we need to be notified first */
};

should be:

static struct notifier_block hw_breakpoint_exceptions_nb = {
.notifier_call = hw_breakpoint_exceptions_notify,
/* We need to be notified first: */
.priority = 0x7fffffff,
};

Ingo