From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.kernel.org ([198.145.29.99]) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1hRh7y-0004vY-Ix for linux-um@lists.infradead.org; Fri, 17 May 2019 17:58:44 +0000 MIME-Version: 1.0 In-Reply-To: <20190514221711.248228-5-brendanhiggins@google.com> References: <20190514221711.248228-1-brendanhiggins@google.com> <20190514221711.248228-5-brendanhiggins@google.com> Subject: Re: [PATCH v4 04/18] kunit: test: add kunit_stream a std::stream like logger From: Stephen Boyd Date: Fri, 17 May 2019 10:58:41 -0700 Message-Id: <20190517175841.F3396216FD@mail.kernel.org> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-um" Errors-To: linux-um-bounces+geert=linux-m68k.org@lists.infradead.org To: Brendan Higgins , frowand.list@gmail.com, gregkh@linuxfoundation.org, jpoimboe@redhat.com, keescook@google.com, kieran.bingham@ideasonboard.com, mcgrof@kernel.org, peterz@infradead.org, robh@kernel.org, shuah@kernel.org, tytso@mit.edu, yamada.masahiro@socionext.com Cc: pmladek@suse.com, linux-doc@vger.kernel.org, amir73il@gmail.com, Brendan Higgins , dri-devel@lists.freedesktop.org, Alexander.Levin@microsoft.com, linux-kselftest@vger.kernel.org, linux-nvdimm@lists.01.org, khilman@baylibre.com, knut.omang@oracle.com, wfg@linux.intel.com, joel@jms.id.au, rientjes@google.com, jdike@addtoit.com, dan.carpenter@oracle.com, devicetree@vger.kernel.org, linux-kbuild@vger.kernel.org, Tim.Bird@sony.com, linux-um@lists.infradead.org, rostedt@goodmis.org, julia.lawall@lip6.fr, kunit-dev@googlegroups.com, richard@nod.at, rdunlap@infradead.org, linux-kernel@vger.kernel.org, daniel@ffwll.ch, mpe@ellerman.id.au, linux-fsdevel@vger.kernel.org, logang@deltatee.com Quoting Brendan Higgins (2019-05-14 15:16:57) > diff --git a/kunit/kunit-stream.c b/kunit/kunit-stream.c > new file mode 100644 > index 0000000000000..1884f1b550888 > --- /dev/null > +++ b/kunit/kunit-stream.c > @@ -0,0 +1,152 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * C++ stream style string formatter and printer used in KUnit for outputting > + * KUnit messages. > + * > + * Copyright (C) 2019, Google LLC. > + * Author: Brendan Higgins > + */ > + > +#include > +#include > +#include > + > +static const char *kunit_stream_get_level(struct kunit_stream *this) > +{ > + unsigned long flags; > + const char *level; > + > + spin_lock_irqsave(&this->lock, flags); > + level = this->level; > + spin_unlock_irqrestore(&this->lock, flags); > + > + return level; Please remove this whole function and inline it to the one call-site. > +} > + > +void kunit_stream_set_level(struct kunit_stream *this, const char *level) > +{ > + unsigned long flags; > + > + spin_lock_irqsave(&this->lock, flags); > + this->level = level; > + spin_unlock_irqrestore(&this->lock, flags); I don't get the locking here. What are we protecting against? Are tests running in parallel using the same kunit_stream? If so, why is the level changeable in one call and then adding strings is done in a different function call? It would make sense to combine the level setting and string adding so that it's one atomic operation if it's truly a parallel operation, or remove the locking entirely. > +} > + > +void kunit_stream_add(struct kunit_stream *this, const char *fmt, ...) > +{ > + va_list args; > + struct string_stream *stream = this->internal_stream; > + > + va_start(args, fmt); > + > + if (string_stream_vadd(stream, fmt, args) < 0) > + kunit_err(this->test, "Failed to allocate fragment: %s\n", fmt); > + > + va_end(args); > +} > + > +void kunit_stream_append(struct kunit_stream *this, > + struct kunit_stream *other) > +{ > + struct string_stream *other_stream = other->internal_stream; > + const char *other_content; > + > + other_content = string_stream_get_string(other_stream); > + > + if (!other_content) { > + kunit_err(this->test, > + "Failed to get string from second argument for appending.\n"); > + return; > + } > + > + kunit_stream_add(this, other_content); > +} > + > +void kunit_stream_clear(struct kunit_stream *this) > +{ > + string_stream_clear(this->internal_stream); > +} > + > +void kunit_stream_commit(struct kunit_stream *this) Should this be rather called kunit_stream_flush()? > +{ > + struct string_stream *stream = this->internal_stream; > + struct string_stream_fragment *fragment; > + const char *level; > + char *buf; > + > + level = kunit_stream_get_level(this); > + if (!level) { > + kunit_err(this->test, > + "Stream was committed without a specified log level.\n"); Drop the full-stop? > + level = KERN_ERR; > + kunit_stream_set_level(this, level); > + } > + > + buf = string_stream_get_string(stream); > + if (!buf) { > + kunit_err(this->test, Can you grow a local variable for 'this->test'? It's used many times. Also, 'this' is not very kernel idiomatic. We usually name variables by their type instead of 'this' which is a keyword in other languages. Perhaps it could be named 'kstream'? > + "Could not allocate buffer, dumping stream:\n"); > + list_for_each_entry(fragment, &stream->fragments, node) { > + kunit_err(this->test, fragment->fragment); > + } > + kunit_err(this->test, "\n"); > + goto cleanup; > + } > + > + kunit_printk(level, this->test, buf); > + kfree(buf); > + > +cleanup: > + kunit_stream_clear(this); > +} > + > +static int kunit_stream_init(struct kunit_resource *res, void *context) > +{ > + struct kunit *test = context; > + struct kunit_stream *stream; > + > + stream = kzalloc(sizeof(*stream), GFP_KERNEL); Of course, here it's called 'stream', so maybe it should be 'kstream' here too. > + if (!stream) > + return -ENOMEM; > + > + res->allocation = stream; > + stream->test = test; > + spin_lock_init(&stream->lock); > + stream->internal_stream = new_string_stream(); Can new_string_stream() be renamed to alloc_string_stream()? Sorry, I just see so much C++ isms in here it's hard to read from the kernel developer perspective. > + > + if (!stream->internal_stream) { Nitpick: Please join this to the "allocation" event above instead of keeping it separated. > + kfree(stream); > + return -ENOMEM; > + } > + > + return 0; > +} > + > +static void kunit_stream_free(struct kunit_resource *res) > +{ > + struct kunit_stream *stream = res->allocation; > + > + if (!string_stream_is_empty(stream->internal_stream)) { > + kunit_err(stream->test, > + "End of test case reached with uncommitted stream entries.\n"); > + kunit_stream_commit(stream); > + } > + > + destroy_string_stream(stream->internal_stream); > + kfree(stream); > +} > + > +struct kunit_stream *kunit_new_stream(struct kunit *test) > +{ > + struct kunit_resource *res; > + > + res = kunit_alloc_resource(test, > + kunit_stream_init, > + kunit_stream_free, > + test); > + > + if (res) > + return res->allocation; > + else > + return NULL; Don't have if (...) return ...; else return ..., just return instead of else. _______________________________________________ linux-um mailing list linux-um@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-um