From 7ab71f3244e9f970c29566c5a67e13d1fa38c387 Mon Sep 17 00:00:00 2001 From: Oleg Nesterov Date: Thu, 20 Jun 2013 17:50:13 +0200 Subject: [PATCH] hw_breakpoint: Simplify the "weight" usage in toggle_bp_slot() paths Change toggle_bp_slot() to make "weight" negative if !enable. This way we can always use "+ weight" without additional "if (enable)" check and toggle_bp_task_slot() no longer needs this arg. Reported-by: Vince Weaver Signed-off-by: Oleg Nesterov Acked-by: Frederic Weisbecker Link: http://lkml.kernel.org/r/20130620155013.GA6337@redhat.com Signed-off-by: Ingo Molnar --- kernel/events/hw_breakpoint.c | 20 ++++++++------------ 1 file changed, 8 insertions(+), 12 deletions(-) diff --git a/kernel/events/hw_breakpoint.c b/kernel/events/hw_breakpoint.c index dee0148..5cd4f6d 100644 --- a/kernel/events/hw_breakpoint.c +++ b/kernel/events/hw_breakpoint.c @@ -182,7 +182,7 @@ fetch_this_slot(struct bp_busy_slots *slots, int weight) /* * Add a pinned breakpoint for the given task in our constraint table */ -static void toggle_bp_task_slot(struct perf_event *bp, int cpu, bool enable, +static void toggle_bp_task_slot(struct perf_event *bp, int cpu, enum bp_type_idx type, int weight) { /* tsk_pinned[n-1] is the number of tasks having n>0 breakpoints */ @@ -190,10 +190,7 @@ static void toggle_bp_task_slot(struct perf_event *bp, int cpu, bool enable, int old_idx, new_idx; old_idx = task_bp_pinned(cpu, bp, type) - 1; - if (enable) - new_idx = old_idx + weight; - else - new_idx = old_idx - weight; + new_idx = old_idx + weight; if (old_idx >= 0) tsk_pinned[old_idx]--; @@ -211,22 +208,21 @@ toggle_bp_slot(struct perf_event *bp, bool enable, enum bp_type_idx type, int cpu = bp->cpu; struct task_struct *tsk = bp->hw.bp_target; + if (!enable) + weight = -weight; + /* Pinned counter cpu profiling */ if (!tsk) { - - if (enable) - per_cpu(nr_cpu_bp_pinned[type], bp->cpu) += weight; - else - per_cpu(nr_cpu_bp_pinned[type], bp->cpu) -= weight; + per_cpu(nr_cpu_bp_pinned[type], cpu) += weight; return; } /* Pinned counter task profiling */ if (cpu >= 0) { - toggle_bp_task_slot(bp, cpu, enable, type, weight); + toggle_bp_task_slot(bp, cpu, type, weight); } else { for_each_possible_cpu(cpu) - toggle_bp_task_slot(bp, cpu, enable, type, weight); + toggle_bp_task_slot(bp, cpu, type, weight); } if (enable) -- 2.7.4