57eb60c04d
The -f option is to filter out the information of blocks whose memory has not been released, I noticed some blocks should not be filtered out. Commit9cc7e96aa8("mm/page_owner: record timestamp and pid") records the allocation timestamp (ts_nsec) of all pages. Commit866b485262("mm/page_owner: record the timestamp of all pages during free") records the free timestamp (free_ts_nsec) of all pages. When the page is allocated for the first time, the initial value of free_ts_nsec is 0, and the corresponding time will be obtained when the page is released. But during reallocation the free_ts_nsec will not reset to 0 again. In particular, when page migration occurs, these two timestamps will be the same. Now page_owner_sort removes all text blocks whose free_ts_nsec is not 0 when using -f option. However, this way can only select pages allocated for the first time. If a freed page is reallocated, free_ts_nsec will be less than ts_nsec; if page migration occurs, the two timestamps will be equal. These cases should be considered as pages are not released. So I fix the function is_need() to keep text blocks that meet the above two conditions when using -f option. Link: https://lkml.kernel.org/r/20220812155515.30846-1-caoyixuan2019@email.szu.edu.cn Signed-off-by: Yixuan Cao <caoyixuan2019@email.szu.edu.cn> Cc: Chongxi Zhao <zhaochongxi2019@email.szu.edu.cn> Cc: Jiajian Ye <yejiajian2018@email.szu.edu.cn> Cc: Yuhong Feng <yuhongf@szu.edu.cn> Cc: Liam Mark <lmark@codeaurora.org> Cc: Georgi Djakov <georgi.djakov@linaro.org> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.