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x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: 63EDA4000F X-Rspam-User: X-Rspamd-Server: rspam02 X-Stat-Signature: cm68n79o5o3arzb638j8najwf784wbhj X-HE-Tag: 1685068133-964897 X-HE-Meta: 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 qNP/vC7N 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Thu, 25 May 2023 14:00:39 -0700 Nadav Amit wrote: > From: Nadav Amit > > Functions that are marked as "inline" are currently also not tracable. > This limits tracing functionality for many functions for no reason. > Apparently, this has been done for two reasons. > > First, as described in commit 5963e317b1e9d2a ("ftrace/x86: Do not > change stacks in DEBUG when calling lockdep"), it was intended to > prevent some functions that cannot be traced from being traced as these > functions were marked as inline (among others). > > Yet, this change has been done a decade ago, and according to Steven > Rostedt, ftrace should have improved and hopefully resolved nested > tracing issues by now. Arguably, if functions that should be traced - > for instance since they are used during tracing - still exist, they > should be marked as notrace explicitly. > > The second reason, which Steven raised, is that attaching "notrace" to > "inline" prevented tracing differences between different configs, which > caused various problem. This consideration is not very strong, and tying > "inline" and "notrace" does not seem very beneficial. The "inline" > keyword is just a hint, and many functions are currently not tracable > due to this reason. > > Disconnect "inline" from "notrace". FYI, I have a patch queued (still needs to go through testing) that already does this ;-) https://lore.kernel.org/all/20230502164102.1a51cdb4@gandalf.local.home/ -- Steve