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Tue, 20 Feb 2024 07:16:48 +0000 (UTC) Received: from dovecot-director2.suse.de ([10.150.64.162]) by imap1.dmz-prg2.suse.org with ESMTPSA id A8MCCOBR1GUmRAAAD6G6ig (envelope-from ); Tue, 20 Feb 2024 07:16:48 +0000 Message-ID: <427e3fdb-5be2-4ff3-9bad-a21c49d0aab4@suse.de> Date: Tue, 20 Feb 2024 08:16:46 +0100 Precedence: bulk X-Mailing-List: linux-scsi@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [LSF/MM/BPF TOPIC] Reclaiming & documenting page flags Content-Language: en-US To: Matthew Wilcox , Mike Rapoport Cc: lsf-pc@lists.linux-foundation.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-block@vger.kernel.org, linux-ide@vger.kernel.org, linux-scsi@vger.kernel.org, linux-nvme@lists.infradead.org, bpf@vger.kernel.org References: From: Hannes Reinecke In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Spam-Level: Authentication-Results: smtp-out1.suse.de; dkim=pass header.d=suse.de header.s=susede2_rsa header.b=2ZP2VMC6; dkim=pass header.d=suse.de header.s=susede2_ed25519 header.b=yZBmTjiY X-Rspamd-Server: rspamd2.dmz-prg2.suse.org X-Spamd-Result: default: False [-4.50 / 50.00]; ARC_NA(0.00)[]; RCVD_VIA_SMTP_AUTH(0.00)[]; R_DKIM_ALLOW(-0.20)[suse.de:s=susede2_rsa,suse.de:s=susede2_ed25519]; XM_UA_NO_VERSION(0.01)[]; FROM_HAS_DN(0.00)[]; TO_DN_SOME(0.00)[]; TO_MATCH_ENVRCPT_ALL(0.00)[]; BAYES_HAM(-3.00)[100.00%]; MIME_GOOD(-0.10)[text/plain]; SPAMHAUS_XBL(0.00)[2a07:de40:b281:104:10:150:64:97:from]; NEURAL_HAM_LONG(-1.00)[-1.000]; RCVD_COUNT_THREE(0.00)[3]; DKIM_SIGNED(0.00)[suse.de:s=susede2_rsa,suse.de:s=susede2_ed25519]; DKIM_TRACE(0.00)[suse.de:+]; MX_GOOD(-0.01)[]; RCPT_COUNT_SEVEN(0.00)[10]; DBL_BLOCKED_OPENRESOLVER(0.00)[suse.de:dkim,suse.de:email]; FUZZY_BLOCKED(0.00)[rspamd.com]; FROM_EQ_ENVFROM(0.00)[]; MIME_TRACE(0.00)[0:+]; NEURAL_HAM_SHORT(-0.20)[-1.000]; RCVD_TLS_ALL(0.00)[]; MID_RHS_MATCH_FROM(0.00)[] X-Spam-Score: -4.50 X-Rspamd-Queue-Id: 335122203C X-Spam-Flag: NO On 2/19/24 21:13, Matthew Wilcox wrote: > On Wed, Feb 07, 2024 at 05:51:44PM +0200, Mike Rapoport wrote: >> On Sun, Feb 04, 2024 at 09:34:01PM +0000, Matthew Wilcox wrote: >>> I'm doing my best to write documentation as I go. I think we're a bit >>> better off than we were last year. Do we have scripts to tell us which >>> public functions (ie EXPORT_SYMBOL and static inline functions in header >>> files) have kernel-doc? And could we run them against kernels from, say, >>> April 2023, 2022, 2021, 2020, 2019 (and in two months against April 2024) >>> and see how we're doing in terms of percentage undocumented functions? >> >> We didn't have such script, but it was easy to compare "grep >> EXPORT_SYMBOL\|static inline" with ".. c:function" in kernel-doc. >> We do improve slowly, but we are still below 50% with kernel-doc for >> EXPORT_SYMBOL functions and slightly above 10% for static inlines. > > Thanks for doing this! Data is good ;-) > > I just came across an interesting example of a function which I believe > should NOT have kernel-doc. But it should have documentation for why it > doesn't have kernel-doc! Any thoughts about how we might accomplish that? > > The example is filemap_range_has_writeback(). It's EXPORT_SYMBOL_GPL() > and it's a helper function for filemap_range_needs_writeback(). > filemap_range_needs_writeback() has kernel-doc, but nobody should be > calling filemap_range_has_writeback() directly, so it shouldn't even > exist in the htmldocs. But we should have a comment on it saying > "Use filemap_range_needs_writeback(), don't use this", in case anyone > discovers it. And the existance of that comment should be enough to > tell our tools to not flag this as a function that needs kernel-doc. > > Or, indeed, coming up with a method of signalling "this is an internal function for a specific need, don't use otherwise". EXPORT_SYMBOL_INTERNAL? I would love to have it; it would solve _so_ many problems we're having wrt kABI... Cheers, Hannes -- Dr. Hannes Reinecke Kernel Storage Architect hare@suse.de +49 911 74053 688 SUSE Software Solutions GmbH, Frankenstr. 146, 90461 Nürnberg HRB 36809 (AG Nürnberg), GF: I. Totev, A. McDonald, W. Knoblich