Commit 4dc0da86 authored by Avi Kivity's avatar Avi Kivity Committed by Ingo Molnar
Browse files

perf: Add context field to perf_event 



The perf_event overflow handler does not receive any caller-derived
argument, so many callers need to resort to looking up the perf_event
in their local data structure.  This is ugly and doesn't scale if a
single callback services many perf_events.

Fix by adding a context parameter to perf_event_create_kernel_counter()
(and derived hardware breakpoints APIs) and storing it in the perf_event.
The field can be accessed from the callback as event->overflow_handler_context.
All callers are updated.

Signed-off-by: default avatarAvi Kivity <avi@redhat.com>
Signed-off-by: default avatarPeter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1309362157-6596-2-git-send-email-avi@redhat.com


Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent 89d6c0b5

arch/arm/kernel/ptrace.c

+2 −1
Original line number Diff line number Diff line
@@ -479,7 +479,8 @@ static struct perf_event *ptrace_hbp_create(struct task_struct *tsk, int type) 
	attr.bp_type	= type;

	attr.disabled	= 1;



	return register_user_hw_breakpoint(&attr, ptrace_hbptriggered, tsk);

	return register_user_hw_breakpoint(&attr, ptrace_hbptriggered, NULL,

					   tsk);

}



static int ptrace_gethbpregs(struct task_struct *tsk, long num,

arch/powerpc/kernel/ptrace.c

+1 −1
Original line number Diff line number Diff line
@@ -973,7 +973,7 @@ int ptrace_set_debugreg(struct task_struct *task, unsigned long addr, 
								&attr.bp_type);



	thread->ptrace_bps[0] = bp = register_user_hw_breakpoint(&attr,

							ptrace_triggered, task);

					       ptrace_triggered, NULL, task);

	if (IS_ERR(bp)) {

		thread->ptrace_bps[0] = NULL;

		ptrace_put_breakpoints(task);

arch/sh/kernel/ptrace_32.c

+2 −1
Original line number Diff line number Diff line
@@ -91,7 +91,8 @@ static int set_single_step(struct task_struct *tsk, unsigned long addr) 
		attr.bp_len = HW_BREAKPOINT_LEN_2;

		attr.bp_type = HW_BREAKPOINT_R;



		bp = register_user_hw_breakpoint(&attr, ptrace_triggered, tsk);

		bp = register_user_hw_breakpoint(&attr, ptrace_triggered,

						 NULL, tsk);

		if (IS_ERR(bp))

			return PTR_ERR(bp);

arch/x86/kernel/kgdb.c

+1 −1
Original line number Diff line number Diff line
@@ -638,7 +638,7 @@ void kgdb_arch_late(void) 
	for (i = 0; i < HBP_NUM; i++) {

		if (breakinfo[i].pev)

			continue;

		breakinfo[i].pev = register_wide_hw_breakpoint(&attr, NULL);

		breakinfo[i].pev = register_wide_hw_breakpoint(&attr, NULL, NULL);

		if (IS_ERR((void * __force)breakinfo[i].pev)) {

			printk(KERN_ERR "kgdb: Could not allocate hw"

			       "breakpoints\nDisabling the kernel debugger\n");

arch/x86/kernel/ptrace.c

+2 −1
Original line number Diff line number Diff line
@@ -715,7 +715,8 @@ static int ptrace_set_breakpoint_addr(struct task_struct *tsk, int nr, 
		attr.bp_type = HW_BREAKPOINT_W;

		attr.disabled = 1;



		bp = register_user_hw_breakpoint(&attr, ptrace_triggered, tsk);

		bp = register_user_hw_breakpoint(&attr, ptrace_triggered,

						 NULL, tsk);



		/*

		 * CHECKME: the previous code returned -EIO if the addr wasn't

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