From b84fbc9fb1d943e2c5f4efe52ed0e3c93a4bdb6a Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Mon, 22 Jun 2009 13:57:40 +0200 Subject: [PATCH] perf_counter: Push inherit into perf_counter_alloc() Teach perf_counter_alloc() about inheritance so that we can optimize the inherit path in the next patch. Remove the child_counter->atrr.inherit = 1 line because the only way to get there is if parent_counter->attr.inherit == 1 and we copy the attrs. Signed-off-by: Peter Zijlstra Cc: Mike Galbraith Cc: Paul Mackerras Cc: Arnaldo Carvalho de Melo LKML-Reference: Signed-off-by: Ingo Molnar --- kernel/perf_counter.c | 14 ++++++-------- 1 file changed, 6 insertions(+), 8 deletions(-) diff --git a/kernel/perf_counter.c b/kernel/perf_counter.c index 7515c76..0a45490 100644 --- a/kernel/perf_counter.c +++ b/kernel/perf_counter.c @@ -3568,6 +3568,7 @@ perf_counter_alloc(struct perf_counter_attr *attr, int cpu, struct perf_counter_context *ctx, struct perf_counter *group_leader, + struct perf_counter *parent_counter, gfp_t gfpflags) { const struct pmu *pmu; @@ -3603,6 +3604,8 @@ perf_counter_alloc(struct perf_counter_attr *attr, counter->ctx = ctx; counter->oncpu = -1; + counter->parent = parent_counter; + counter->ns = get_pid_ns(current->nsproxy->pid_ns); counter->id = atomic64_inc_return(&perf_counter_id); @@ -3827,7 +3830,7 @@ SYSCALL_DEFINE5(perf_counter_open, } counter = perf_counter_alloc(&attr, cpu, ctx, group_leader, - GFP_KERNEL); + NULL, GFP_KERNEL); ret = PTR_ERR(counter); if (IS_ERR(counter)) goto err_put_context; @@ -3893,7 +3896,8 @@ inherit_counter(struct perf_counter *parent_counter, child_counter = perf_counter_alloc(&parent_counter->attr, parent_counter->cpu, child_ctx, - group_leader, GFP_KERNEL); + group_leader, parent_counter, + GFP_KERNEL); if (IS_ERR(child_counter)) return child_counter; get_ctx(child_ctx); @@ -3916,12 +3920,6 @@ inherit_counter(struct perf_counter *parent_counter, */ add_counter_to_ctx(child_counter, child_ctx); - child_counter->parent = parent_counter; - /* - * inherit into child's child as well: - */ - child_counter->attr.inherit = 1; - /* * Get a reference to the parent filp - we will fput it * when the child counter exits. This is safe to do because -- 2.7.4