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charset=us-ascii Content-Disposition: inline In-Reply-To: <14089609-5fb1-b082-716f-c2e129d27c48@suse.cz> User-Agent: Mutt/1.12.2 (2019-09-21) 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 Fri, Mar 06, 2020 at 12:14:19PM +0100, Vlastimil Babka wrote: > On 3/2/20 8:36 PM, Minchan Kim wrote: > > There is a demand[1] to support pid as well pidfd for process_madvise > > to reduce unnecessary syscall to get pidfd if the user has control of > > the target process(ie, they could guarantee the process is not gone > > or pid is not reused). > > > > This patch aims for supporting both options like waitid(2). So, the > > syscall is currently, > > > > int process_madvise(int which, pid_t pid, void *addr, > > size_t length, int advise, unsigned long flag); > > This is again halfway between kernel and userspace description, so if we stick > to userspace then it's: > > int process_madvise(idtype_t idtype, id_t id, void *addr, > size_t length, int advice, unsigned long flags); Yub. > > > > @which is actually idtype_t for userspace libray and currently, > > it supports P_PID and P_PIDFD. > > > > [1] https://lore.kernel.org/linux-mm/9d849087-3359-c4ab-fbec-859e8186c509@virtuozzo.com/ > > > > Cc: Christian Brauner > > Reviewed-by: Suren Baghdasaryan > > Suggested-by: Kirill Tkhai > > Signed-off-by: Minchan Kim > > Reviewed-by: Vlastimil Babka Thanks!