From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 46DFD3EA85; Mon, 22 Jan 2024 16:07:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1705939643; cv=none; b=pxKpJFxMGmnwaxYq2MHfbWqVUXpt8OU7I6jC3IsOBqAVulJmotJCjGoPNXJQmQKU4j6Bim223BtcDucL0Qi9jc34N1/fqJpTLSzl0argAp9dYSGuTK2MGeXaEpWkA7xOEBBC8JHu5DPDP4e2wt6Rju4yAD2wYtySO3Mbe8quaUo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1705939643; c=relaxed/simple; bh=Y0YnSaZ7rJJoYHHQKixkCTtvD+62+VNE4Ysym1ByEns=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=uHABAz5PoBr4BEurcx+ljmp5HVrimzmD4pI+/N0XY04fqBlqzwOZuqKuQ7J2MSXvLXSgKVE3lw03w4sMbts3bI8mcBYu+FDnHYibf9x41Jmoe1uUa4oW5hYaNyRP4wgZcvbpEaJ2EFdydbfSFu3H3rUGzoNoIJ/E8Wsdkih7wJo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5EFA5C433F1; Mon, 22 Jan 2024 16:07:22 +0000 (UTC) Date: Mon, 22 Jan 2024 11:08:50 -0500 From: Steven Rostedt To: Ye Bin Cc: , , , Subject: Re: [PATCH v2 2/7] tracing/probes: add traceprobe_expand_dentry_args() helper Message-ID: <20240122110850.4978f510@gandalf.local.home> In-Reply-To: <20240122074015.4042575-3-yebin10@huawei.com> References: <20240122074015.4042575-1-yebin10@huawei.com> <20240122074015.4042575-3-yebin10@huawei.com> X-Mailer: Claws Mail 3.19.1 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit On Mon, 22 Jan 2024 15:40:10 +0800 Ye Bin wrote: > Add traceprobe_expand_dentry_args() to expand dentry args. this API is > prepare to support "%pd" print format for kprobe. > > Signed-off-by: Ye Bin > --- > kernel/trace/trace_probe.c | 34 ++++++++++++++++++++++++++++++++++ > kernel/trace/trace_probe.h | 2 ++ > 2 files changed, 36 insertions(+) > > diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c > index 4dc74d73fc1d..1599c0c3e6b7 100644 > --- a/kernel/trace/trace_probe.c > +++ b/kernel/trace/trace_probe.c > @@ -1565,6 +1565,40 @@ const char **traceprobe_expand_meta_args(int argc, const char *argv[], > return ERR_PTR(ret); > } > > +int traceprobe_expand_dentry_args(int argc, const char *argv[], char *buf, > + int bufsize) > +{ > + int i, used, ret; size_t idx; > + > + used = 0; > + for (i = 0; i < argc; i++) { > + if (str_has_suffix(argv[i], ":%pd")) { If we were to update str_has_suffix() as I said in my reply to the previous patch, then we could do: if (str_has_suffix(argv[i], ":%pd", &idx) { > + char *tmp = kstrdup(argv[i], GFP_KERNEL); > + char *equal; > + > + if (!tmp) > + return -ENOMEM; > + > + equal = strchr(tmp, '='); > + if (equal) > + *equal = '\0'; > + tmp[strlen(argv[i]) - 4] = '\0'; tmp[idx] = '\0'; -- Steve > + ret = snprintf(buf + used, bufsize - used, > + "%s%s+0x0(+0x%zx(%s)):string", > + equal ? tmp : "", equal ? "=" : "", > + offsetof(struct dentry, d_name.name), > + equal ? equal + 1 : tmp); > + kfree(tmp); > + if (ret >= bufsize - used) > + return -ENOMEM; > + argv[i] = buf + used; > + used += ret + 1; > + } > + } > + > + return 0; > +} > + > void traceprobe_finish_parse(struct traceprobe_parse_context *ctx) > { > clear_btf_context(ctx); > diff --git a/kernel/trace/trace_probe.h b/kernel/trace/trace_probe.h > index 850d9ecb6765..553371a4e0b1 100644 > --- a/kernel/trace/trace_probe.h > +++ b/kernel/trace/trace_probe.h > @@ -402,6 +402,8 @@ extern int traceprobe_parse_probe_arg(struct trace_probe *tp, int i, > const char **traceprobe_expand_meta_args(int argc, const char *argv[], > int *new_argc, char *buf, int bufsize, > struct traceprobe_parse_context *ctx); > +extern int traceprobe_expand_dentry_args(int argc, const char *argv[], char *buf, > + int bufsize); > > extern int traceprobe_update_arg(struct probe_arg *arg); > extern void traceprobe_free_probe_arg(struct probe_arg *arg);