From 87f44bbc246c5244c76a701f8eefba7788bce64a Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Tue, 25 May 2010 11:02:55 +0200 Subject: [PATCH] perf, trace: Fix !x86 build bug Patch b7e2ecef92 (perf, trace: Optimize tracepoints by removing IRQ-disable from perf/tracepoint interaction) made the unfortunate mistake of assuming the world is x86 only, correct this. The problem was that perf_fetch_caller_regs() did local_save_flags() into regs->flags, and I re-used that to remove another local_save_flags(), forgetting !x86 doesn't have regs->flags. Do the reverse, remove the local_save_flags() from perf_fetch_caller_regs() and let the ftrace site do the local_save_flags() instead. Signed-off-by: Peter Zijlstra Acked-by: Paul Mackerras Cc: acme@redhat.com Cc: efault@gmx.de Cc: fweisbec@gmail.com Cc: rostedt@goodmis.org LKML-Reference: <1274778175.5882.623.camel@twins> Signed-off-by: Ingo Molnar --- arch/x86/kernel/cpu/perf_event.c | 6 +++++- kernel/trace/trace_event_perf.c | 4 +++- 2 files changed, 8 insertions(+), 2 deletions(-) diff --git a/arch/x86/kernel/cpu/perf_event.c b/arch/x86/kernel/cpu/perf_event.c index fd4db0db3708..c77586061bcb 100644 --- a/arch/x86/kernel/cpu/perf_event.c +++ b/arch/x86/kernel/cpu/perf_event.c @@ -1717,7 +1717,11 @@ void perf_arch_fetch_caller_regs(struct pt_regs *regs, unsigned long ip, int ski */ regs->bp = rewind_frame_pointer(skip + 1); regs->cs = __KERNEL_CS; - local_save_flags(regs->flags); + /* + * We abuse bit 3 to pass exact information, see perf_misc_flags + * and the comment with PERF_EFLAGS_EXACT. + */ + regs->flags = 0; } unsigned long perf_instruction_pointer(struct pt_regs *regs) diff --git a/kernel/trace/trace_event_perf.c b/kernel/trace/trace_event_perf.c index 26b8607a0abc..cb6f365016e4 100644 --- a/kernel/trace/trace_event_perf.c +++ b/kernel/trace/trace_event_perf.c @@ -157,6 +157,7 @@ __kprobes void *perf_trace_buf_prepare(int size, unsigned short type, struct pt_regs *regs, int *rctxp) { struct trace_entry *entry; + unsigned long flags; char *raw_data; int pc; @@ -174,7 +175,8 @@ __kprobes void *perf_trace_buf_prepare(int size, unsigned short type, memset(&raw_data[size - sizeof(u64)], 0, sizeof(u64)); entry = (struct trace_entry *)raw_data; - tracing_generic_entry_update(entry, regs->flags, pc); + local_save_flags(flags); + tracing_generic_entry_update(entry, flags, pc); entry->type = type; return raw_data; -- 2.20.1