Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932795AbZFQFGY (ORCPT ); Wed, 17 Jun 2009 01:06:24 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932783AbZFQFGJ (ORCPT ); Wed, 17 Jun 2009 01:06:09 -0400 Received: from mail-ew0-f210.google.com ([209.85.219.210]:46957 "EHLO mail-ew0-f210.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932778AbZFQFGI (ORCPT ); Wed, 17 Jun 2009 01:06:08 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=date:from:to:cc:subject:message-id:references:mime-version :content-type:content-disposition:in-reply-to:user-agent; b=DLKmSzCCbaRwe4Pj1lvKVth40pBO/Lagpkmszi5V+hq3FnbyIU+22jlNjlhxcbsaAb L0SLvMe6EtQk9QdqxI3ocTGImcZkQEeXrPtDAInRvnR4nBFwbqSij7EMzwrKiY0Z+wSP cdNkAqb2tZfi45y4UB1UUomOyZ8ty8UQAjrq4= Date: Wed, 17 Jun 2009 07:06:07 +0200 From: Frederic Weisbecker To: "K.Prasad" Cc: Ingo Molnar , Linux Kernel Mailing List Subject: Re: [Patch 1/2] ksym_tracer:Fix line-wrapping after removal of ksym tracer entry Message-ID: <20090617050605.GC7411@nowhere> References: <20090616225257.041883212@prasadkr_t60p.in.ibm.com> <20090616230504.GB14753@in.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20090616230504.GB14753@in.ibm.com> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2491 Lines: 83 On Wed, Jun 17, 2009 at 04:35:04AM +0530, K.Prasad wrote: > Removal of a ksym entry results in missing information and an early return with > TRACE_TYPE_PARTIAL_LINE code (minus the line return). This patch modifies the > output function to unconditionally add a line return irrespective of the > return code. > > Signed-off-by: K.Prasad > --- > kernel/trace/trace_ksym.c | 27 +++++++++++++++------------ > 1 file changed, 15 insertions(+), 12 deletions(-) > > Index: linux-2.6-tip.hbkpt/kernel/trace/trace_ksym.c > =================================================================== > --- linux-2.6-tip.hbkpt.orig/kernel/trace/trace_ksym.c > +++ linux-2.6-tip.hbkpt/kernel/trace/trace_ksym.c > @@ -391,29 +391,32 @@ static enum print_line_t ksym_trace_outp > > ret = trace_seq_printf(s, "%-15s %-5d %-3d %-20s ", field->p_name, > entry->pid, iter->cpu, field->ksym_name); > - if (!ret) > - return TRACE_TYPE_PARTIAL_LINE; > + if (!ret) { > + ret = TRACE_TYPE_PARTIAL_LINE; > + goto err_ret; > + } > > + ret = TRACE_TYPE_PARTIAL_LINE; > switch (field->ksym_hbp->info.type) { > case HW_BREAKPOINT_WRITE: > - ret = trace_seq_printf(s, " W "); > + if (!trace_seq_printf(s, " W ")) > + goto err_ret; > break; > case HW_BREAKPOINT_RW: > - ret = trace_seq_printf(s, " RW "); > + if (!trace_seq_printf(s, " RW ")) > + goto err_ret; > break; > default: > - return TRACE_TYPE_PARTIAL_LINE; > + goto err_ret; > } > > - if (!ret) > - return TRACE_TYPE_PARTIAL_LINE; > - > sprint_symbol(str, field->ip); > ret = trace_seq_printf(s, "%-20s\n", str); > - if (!ret) > - return TRACE_TYPE_PARTIAL_LINE; > - > - return TRACE_TYPE_HANDLED; > + if (ret) > + return TRACE_TYPE_HANDLED; > +err_ret: > + trace_seq_printf(s, "\n"); > + return ret; As told in my email just before, TRACE_TYPE_PARTIAL_LINE won't print a truncated line or a partial line. Instead, it will be ignored and entirely retried later. Then your newline will be ignored. ..unless we have a bug in trace.c I'm not sure what it the origin of the concatenated printed entries Ingo has reported. Did you reproduce it and then this patch fixed it? > } > > struct tracer ksym_tracer __read_mostly = > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/