From f9188e023c248d73f5b4a589b480e065c1864068 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra <a.p.zijlstra@chello.nl> Date: Thu, 18 Jun 2009 22:20:52 +0200 Subject: perf_counter: Make callchain samples extensible Before exposing upstream tools to a callchain-samples ABI, tidy it up to make it more extensible in the future: Use markers in the IP chain to denote context, use (u64)-1..-4095 range for these context markers because we use them for ERR_PTR(), so these addresses are unlikely to be mapped. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> LKML-Reference: <new-submission> Signed-off-by: Ingo Molnar <mingo@elte.hu> --- arch/x86/kernel/cpu/perf_counter.c | 29 ++++++----------------------- 1 file changed, 6 insertions(+), 23 deletions(-) (limited to 'arch') diff --git a/arch/x86/kernel/cpu/perf_counter.c b/arch/x86/kernel/cpu/perf_counter.c index ce1ae3f1f86c..76dfef23f789 100644 --- a/arch/x86/kernel/cpu/perf_counter.c +++ b/arch/x86/kernel/cpu/perf_counter.c @@ -1555,9 +1555,9 @@ const struct pmu *hw_perf_counter_init(struct perf_counter *counter) */ static inline -void callchain_store(struct perf_callchain_entry *entry, unsigned long ip) +void callchain_store(struct perf_callchain_entry *entry, u64 ip) { - if (entry->nr < MAX_STACK_DEPTH) + if (entry->nr < PERF_MAX_STACK_DEPTH) entry->ip[entry->nr++] = ip; } @@ -1602,22 +1602,10 @@ static const struct stacktrace_ops backtrace_ops = { static void perf_callchain_kernel(struct pt_regs *regs, struct perf_callchain_entry *entry) { - unsigned long bp; - char *stack; - int nr = entry->nr; - + callchain_store(entry, PERF_CONTEXT_KERNEL); callchain_store(entry, regs->ip); - stack = ((char *)regs + sizeof(struct pt_regs)); -#ifdef CONFIG_FRAME_POINTER - get_bp(bp); -#else - bp = 0; -#endif - - dump_trace(NULL, regs, (void *)&stack, bp, &backtrace_ops, entry); - - entry->kernel = entry->nr - nr; + dump_trace(NULL, regs, NULL, 0, &backtrace_ops, entry); } /* @@ -1669,16 +1657,16 @@ perf_callchain_user(struct pt_regs *regs, struct perf_callchain_entry *entry) { struct stack_frame frame; const void __user *fp; - int nr = entry->nr; if (!user_mode(regs)) regs = task_pt_regs(current); fp = (void __user *)regs->bp; + callchain_store(entry, PERF_CONTEXT_USER); callchain_store(entry, regs->ip); - while (entry->nr < MAX_STACK_DEPTH) { + while (entry->nr < PERF_MAX_STACK_DEPTH) { frame.next_frame = NULL; frame.return_address = 0; @@ -1691,8 +1679,6 @@ perf_callchain_user(struct pt_regs *regs, struct perf_callchain_entry *entry) callchain_store(entry, frame.return_address); fp = frame.next_frame; } - - entry->user = entry->nr - nr; } static void @@ -1728,9 +1714,6 @@ struct perf_callchain_entry *perf_callchain(struct pt_regs *regs) entry = &__get_cpu_var(irq_entry); entry->nr = 0; - entry->hv = 0; - entry->kernel = 0; - entry->user = 0; perf_do_callchain(regs, entry); -- cgit v1.2.3