From 3c502e7a0255d82621ff25d60cc816624830497e Mon Sep 17 00:00:00 2001 From: Jason Wessel Date: Thu, 4 Nov 2010 17:33:01 -0500 Subject: perf,hw_breakpoint: Initialize hardware api earlier When using early debugging, the kernel does not initialize the hw_breakpoint API early enough and causes the late initialization of the kernel debugger to fail. The boot arguments are: earlyprintk=vga ekgdboc=kbd kgdbwait Then simply type "go" at the kdb prompt and boot. The kernel will later emit the message: kgdb: Could not allocate hwbreakpoints And at that point the kernel debugger will cease to work correctly. The solution is to initialize the hw_breakpoint at the same time that all the other perf call backs are initialized instead of using a core_initcall() initialization which happens well after the kernel debugger can make use of hardware breakpoints. Signed-off-by: Jason Wessel CC: Frederic Weisbecker CC: Ingo Molnar CC: Peter Zijlstra LKML-Reference: <4CD3396D.1090308@windriver.com> Signed-off-by: Frederic Weisbecker --- kernel/hw_breakpoint.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) (limited to 'kernel/hw_breakpoint.c') diff --git a/kernel/hw_breakpoint.c b/kernel/hw_breakpoint.c index 2c9120f0afca..e5325825aeb6 100644 --- a/kernel/hw_breakpoint.c +++ b/kernel/hw_breakpoint.c @@ -620,7 +620,7 @@ static struct pmu perf_breakpoint = { .read = hw_breakpoint_pmu_read, }; -static int __init init_hw_breakpoint(void) +int __init init_hw_breakpoint(void) { unsigned int **task_bp_pinned; int cpu, err_cpu; @@ -655,6 +655,5 @@ static int __init init_hw_breakpoint(void) return -ENOMEM; } -core_initcall(init_hw_breakpoint); -- cgit v1.2.2 From 2e80a82a49c4c7eca4e35734380f28298ba5db19 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Wed, 17 Nov 2010 23:17:36 +0100 Subject: perf: Dynamic pmu types Extend the perf_pmu_register() interface to allow for named and dynamic pmu types. Because we need to support the existing static types we cannot use dynamic types for everything, hence provide a type argument. If we want to enumerate the PMUs they need a name, provide one. Signed-off-by: Peter Zijlstra LKML-Reference: <20101117222056.259707703@chello.nl> Signed-off-by: Ingo Molnar --- kernel/hw_breakpoint.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'kernel/hw_breakpoint.c') diff --git a/kernel/hw_breakpoint.c b/kernel/hw_breakpoint.c index e5325825aeb6..086adf25a55e 100644 --- a/kernel/hw_breakpoint.c +++ b/kernel/hw_breakpoint.c @@ -641,7 +641,7 @@ int __init init_hw_breakpoint(void) constraints_initialized = 1; - perf_pmu_register(&perf_breakpoint); + perf_pmu_register(&perf_breakpoint, "breakpoint", PERF_TYPE_BREAKPOINT); return register_die_notifier(&hw_breakpoint_exceptions_nb); -- cgit v1.2.2