Commit 71a851b4 authored by Peter Zijlstra's avatar Peter Zijlstra Committed by Ingo Molnar
Browse files

perf_counter: Stop open coding unclone_ctx 



Instead of open coding the unclone context thingy, put it in
a common function.

Signed-off-by: default avatarPeter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent 984b838c

kernel/perf_counter.c

+17 −19
Original line number Diff line number Diff line
@@ -146,6 +146,14 @@ static void put_ctx(struct perf_counter_context *ctx) 
	}

}



static void unclone_ctx(struct perf_counter_context *ctx)

{

	if (ctx->parent_ctx) {

		put_ctx(ctx->parent_ctx);

		ctx->parent_ctx = NULL;

	}

}



/*

 * Get the perf_counter_context for a task and lock it.

 * This has to cope with with the fact that until it is locked,
@@ -1463,10 +1471,8 @@ static void perf_counter_enable_on_exec(struct task_struct *task) 
	/*

	 * Unclone this context if we enabled any counter.

	 */

	if (enabled && ctx->parent_ctx) {

		put_ctx(ctx->parent_ctx);

		ctx->parent_ctx = NULL;

	}

	if (enabled)

		unclone_ctx(ctx);



	spin_unlock(&ctx->lock);
@@ -1526,7 +1532,6 @@ __perf_counter_init_context(struct perf_counter_context *ctx, 


static struct perf_counter_context *find_get_context(pid_t pid, int cpu)

{

	struct perf_counter_context *parent_ctx;

	struct perf_counter_context *ctx;

	struct perf_cpu_context *cpuctx;

	struct task_struct *task;
@@ -1586,11 +1591,7 @@ static struct perf_counter_context *find_get_context(pid_t pid, int cpu) 
 retry:

	ctx = perf_lock_task_context(task, &flags);

	if (ctx) {

		parent_ctx = ctx->parent_ctx;

		if (parent_ctx) {

			put_ctx(parent_ctx);

			ctx->parent_ctx = NULL;		/* no longer a clone */

		}

		unclone_ctx(ctx);

		spin_unlock_irqrestore(&ctx->lock, flags);

	}
@@ -4255,15 +4256,12 @@ void perf_counter_exit_task(struct task_struct *child) 
	 */

	spin_lock(&child_ctx->lock);

	child->perf_counter_ctxp = NULL;

	if (child_ctx->parent_ctx) {

	/*

		 * This context is a clone; unclone it so it can't get

	 * If this context is a clone; unclone it so it can't get

	 * swapped to another process while we're removing all

	 * the counters from it.

	 */

		put_ctx(child_ctx->parent_ctx);

		child_ctx->parent_ctx = NULL;

	}

	unclone_ctx(child_ctx);

	spin_unlock(&child_ctx->lock);

	local_irq_restore(flags);