From: Oleksandr Natalenko <oleksandr@redhat.com>
To: Minchan Kim <minchan@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>,
LKML <linux-kernel@vger.kernel.org>,
linux-mm <linux-mm@kvack.org>, Michal Hocko <mhocko@suse.com>,
Johannes Weiner <hannes@cmpxchg.org>,
Tim Murray <timmurray@google.com>,
Joel Fernandes <joel@joelfernandes.org>,
Suren Baghdasaryan <surenb@google.com>,
Daniel Colascione <dancol@google.com>,
Shakeel Butt <shakeelb@google.com>,
Sonny Rao <sonnyrao@google.com>,
Brian Geffon <bgeffon@google.com>
Subject: Re: [RFC 4/7] mm: factor out madvise's core functionality
Date: Mon, 20 May 2019 16:26:33 +0200 [thread overview]
Message-ID: <20190520142633.x5d27gk454qruc4o@butterfly.localdomain> (raw)
In-Reply-To: <20190520035254.57579-5-minchan@kernel.org>
Hi.
On Mon, May 20, 2019 at 12:52:51PM +0900, Minchan Kim wrote:
> This patch factor out madvise's core functionality so that upcoming
> patch can reuse it without duplication.
>
> It shouldn't change any behavior.
>
> Signed-off-by: Minchan Kim <minchan@kernel.org>
> ---
> mm/madvise.c | 168 +++++++++++++++++++++++++++------------------------
> 1 file changed, 89 insertions(+), 79 deletions(-)
>
> diff --git a/mm/madvise.c b/mm/madvise.c
> index 9a6698b56845..119e82e1f065 100644
> --- a/mm/madvise.c
> +++ b/mm/madvise.c
> @@ -742,7 +742,8 @@ static long madvise_dontneed_single_vma(struct vm_area_struct *vma,
> return 0;
> }
>
> -static long madvise_dontneed_free(struct vm_area_struct *vma,
> +static long madvise_dontneed_free(struct task_struct *tsk,
> + struct vm_area_struct *vma,
> struct vm_area_struct **prev,
> unsigned long start, unsigned long end,
> int behavior)
> @@ -754,8 +755,8 @@ static long madvise_dontneed_free(struct vm_area_struct *vma,
> if (!userfaultfd_remove(vma, start, end)) {
> *prev = NULL; /* mmap_sem has been dropped, prev is stale */
>
> - down_read(¤t->mm->mmap_sem);
> - vma = find_vma(current->mm, start);
> + down_read(&tsk->mm->mmap_sem);
> + vma = find_vma(tsk->mm, start);
> if (!vma)
> return -ENOMEM;
> if (start < vma->vm_start) {
> @@ -802,7 +803,8 @@ static long madvise_dontneed_free(struct vm_area_struct *vma,
> * Application wants to free up the pages and associated backing store.
> * This is effectively punching a hole into the middle of a file.
> */
> -static long madvise_remove(struct vm_area_struct *vma,
> +static long madvise_remove(struct task_struct *tsk,
> + struct vm_area_struct *vma,
> struct vm_area_struct **prev,
> unsigned long start, unsigned long end)
> {
> @@ -836,13 +838,13 @@ static long madvise_remove(struct vm_area_struct *vma,
> get_file(f);
> if (userfaultfd_remove(vma, start, end)) {
> /* mmap_sem was not released by userfaultfd_remove() */
> - up_read(¤t->mm->mmap_sem);
> + up_read(&tsk->mm->mmap_sem);
> }
> error = vfs_fallocate(f,
> FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE,
> offset, end - start);
> fput(f);
> - down_read(¤t->mm->mmap_sem);
> + down_read(&tsk->mm->mmap_sem);
> return error;
> }
>
> @@ -916,12 +918,13 @@ static int madvise_inject_error(int behavior,
> #endif
What about madvise_inject_error() and get_user_pages_fast() in it
please?
>
> static long
> -madvise_vma(struct vm_area_struct *vma, struct vm_area_struct **prev,
> - unsigned long start, unsigned long end, int behavior)
> +madvise_vma(struct task_struct *tsk, struct vm_area_struct *vma,
> + struct vm_area_struct **prev, unsigned long start,
> + unsigned long end, int behavior)
> {
> switch (behavior) {
> case MADV_REMOVE:
> - return madvise_remove(vma, prev, start, end);
> + return madvise_remove(tsk, vma, prev, start, end);
> case MADV_WILLNEED:
> return madvise_willneed(vma, prev, start, end);
> case MADV_COOL:
> @@ -930,7 +933,8 @@ madvise_vma(struct vm_area_struct *vma, struct vm_area_struct **prev,
> return madvise_cold(vma, start, end);
> case MADV_FREE:
> case MADV_DONTNEED:
> - return madvise_dontneed_free(vma, prev, start, end, behavior);
> + return madvise_dontneed_free(tsk, vma, prev, start,
> + end, behavior);
> default:
> return madvise_behavior(vma, prev, start, end, behavior);
> }
> @@ -974,68 +978,8 @@ madvise_behavior_valid(int behavior)
> }
> }
>
> -/*
> - * The madvise(2) system call.
> - *
> - * Applications can use madvise() to advise the kernel how it should
> - * handle paging I/O in this VM area. The idea is to help the kernel
> - * use appropriate read-ahead and caching techniques. The information
> - * provided is advisory only, and can be safely disregarded by the
> - * kernel without affecting the correct operation of the application.
> - *
> - * behavior values:
> - * MADV_NORMAL - the default behavior is to read clusters. This
> - * results in some read-ahead and read-behind.
> - * MADV_RANDOM - the system should read the minimum amount of data
> - * on any access, since it is unlikely that the appli-
> - * cation will need more than what it asks for.
> - * MADV_SEQUENTIAL - pages in the given range will probably be accessed
> - * once, so they can be aggressively read ahead, and
> - * can be freed soon after they are accessed.
> - * MADV_WILLNEED - the application is notifying the system to read
> - * some pages ahead.
> - * MADV_DONTNEED - the application is finished with the given range,
> - * so the kernel can free resources associated with it.
> - * MADV_FREE - the application marks pages in the given range as lazy free,
> - * where actual purges are postponed until memory pressure happens.
> - * MADV_REMOVE - the application wants to free up the given range of
> - * pages and associated backing store.
> - * MADV_DONTFORK - omit this area from child's address space when forking:
> - * typically, to avoid COWing pages pinned by get_user_pages().
> - * MADV_DOFORK - cancel MADV_DONTFORK: no longer omit this area when forking.
> - * MADV_WIPEONFORK - present the child process with zero-filled memory in this
> - * range after a fork.
> - * MADV_KEEPONFORK - undo the effect of MADV_WIPEONFORK
> - * MADV_HWPOISON - trigger memory error handler as if the given memory range
> - * were corrupted by unrecoverable hardware memory failure.
> - * MADV_SOFT_OFFLINE - try to soft-offline the given range of memory.
> - * MADV_MERGEABLE - the application recommends that KSM try to merge pages in
> - * this area with pages of identical content from other such areas.
> - * MADV_UNMERGEABLE- cancel MADV_MERGEABLE: no longer merge pages with others.
> - * MADV_HUGEPAGE - the application wants to back the given range by transparent
> - * huge pages in the future. Existing pages might be coalesced and
> - * new pages might be allocated as THP.
> - * MADV_NOHUGEPAGE - mark the given range as not worth being backed by
> - * transparent huge pages so the existing pages will not be
> - * coalesced into THP and new pages will not be allocated as THP.
> - * MADV_DONTDUMP - the application wants to prevent pages in the given range
> - * from being included in its core dump.
> - * MADV_DODUMP - cancel MADV_DONTDUMP: no longer exclude from core dump.
> - *
> - * return values:
> - * zero - success
> - * -EINVAL - start + len < 0, start is not page-aligned,
> - * "behavior" is not a valid value, or application
> - * is attempting to release locked or shared pages,
> - * or the specified address range includes file, Huge TLB,
> - * MAP_SHARED or VMPFNMAP range.
> - * -ENOMEM - addresses in the specified range are not currently
> - * mapped, or are outside the AS of the process.
> - * -EIO - an I/O error occurred while paging in data.
> - * -EBADF - map exists, but area maps something that isn't a file.
> - * -EAGAIN - a kernel resource was temporarily unavailable.
> - */
> -SYSCALL_DEFINE3(madvise, unsigned long, start, size_t, len_in, int, behavior)
> +static int madvise_core(struct task_struct *tsk, unsigned long start,
> + size_t len_in, int behavior)
> {
> unsigned long end, tmp;
> struct vm_area_struct *vma, *prev;
> @@ -1071,10 +1015,10 @@ SYSCALL_DEFINE3(madvise, unsigned long, start, size_t, len_in, int, behavior)
>
> write = madvise_need_mmap_write(behavior);
> if (write) {
> - if (down_write_killable(¤t->mm->mmap_sem))
> + if (down_write_killable(&tsk->mm->mmap_sem))
> return -EINTR;
> } else {
> - down_read(¤t->mm->mmap_sem);
> + down_read(&tsk->mm->mmap_sem);
> }
>
> /*
> @@ -1082,7 +1026,7 @@ SYSCALL_DEFINE3(madvise, unsigned long, start, size_t, len_in, int, behavior)
> * ranges, just ignore them, but return -ENOMEM at the end.
> * - different from the way of handling in mlock etc.
> */
> - vma = find_vma_prev(current->mm, start, &prev);
> + vma = find_vma_prev(tsk->mm, start, &prev);
> if (vma && start > vma->vm_start)
> prev = vma;
>
> @@ -1107,7 +1051,7 @@ SYSCALL_DEFINE3(madvise, unsigned long, start, size_t, len_in, int, behavior)
> tmp = end;
>
> /* Here vma->vm_start <= start < tmp <= (end|vma->vm_end). */
> - error = madvise_vma(vma, &prev, start, tmp, behavior);
> + error = madvise_vma(tsk, vma, &prev, start, tmp, behavior);
> if (error)
> goto out;
> start = tmp;
> @@ -1119,14 +1063,80 @@ SYSCALL_DEFINE3(madvise, unsigned long, start, size_t, len_in, int, behavior)
> if (prev)
> vma = prev->vm_next;
> else /* madvise_remove dropped mmap_sem */
> - vma = find_vma(current->mm, start);
> + vma = find_vma(tsk->mm, start);
> }
> out:
> blk_finish_plug(&plug);
> if (write)
> - up_write(¤t->mm->mmap_sem);
> + up_write(&tsk->mm->mmap_sem);
> else
> - up_read(¤t->mm->mmap_sem);
> + up_read(&tsk->mm->mmap_sem);
>
> return error;
> }
> +
> +/*
> + * The madvise(2) system call.
> + *
> + * Applications can use madvise() to advise the kernel how it should
> + * handle paging I/O in this VM area. The idea is to help the kernel
> + * use appropriate read-ahead and caching techniques. The information
> + * provided is advisory only, and can be safely disregarded by the
> + * kernel without affecting the correct operation of the application.
> + *
> + * behavior values:
> + * MADV_NORMAL - the default behavior is to read clusters. This
> + * results in some read-ahead and read-behind.
> + * MADV_RANDOM - the system should read the minimum amount of data
> + * on any access, since it is unlikely that the appli-
> + * cation will need more than what it asks for.
> + * MADV_SEQUENTIAL - pages in the given range will probably be accessed
> + * once, so they can be aggressively read ahead, and
> + * can be freed soon after they are accessed.
> + * MADV_WILLNEED - the application is notifying the system to read
> + * some pages ahead.
> + * MADV_DONTNEED - the application is finished with the given range,
> + * so the kernel can free resources associated with it.
> + * MADV_FREE - the application marks pages in the given range as lazy free,
> + * where actual purges are postponed until memory pressure happens.
> + * MADV_REMOVE - the application wants to free up the given range of
> + * pages and associated backing store.
> + * MADV_DONTFORK - omit this area from child's address space when forking:
> + * typically, to avoid COWing pages pinned by get_user_pages().
> + * MADV_DOFORK - cancel MADV_DONTFORK: no longer omit this area when forking.
> + * MADV_WIPEONFORK - present the child process with zero-filled memory in this
> + * range after a fork.
> + * MADV_KEEPONFORK - undo the effect of MADV_WIPEONFORK
> + * MADV_HWPOISON - trigger memory error handler as if the given memory range
> + * were corrupted by unrecoverable hardware memory failure.
> + * MADV_SOFT_OFFLINE - try to soft-offline the given range of memory.
> + * MADV_MERGEABLE - the application recommends that KSM try to merge pages in
> + * this area with pages of identical content from other such areas.
> + * MADV_UNMERGEABLE- cancel MADV_MERGEABLE: no longer merge pages with others.
> + * MADV_HUGEPAGE - the application wants to back the given range by transparent
> + * huge pages in the future. Existing pages might be coalesced and
> + * new pages might be allocated as THP.
> + * MADV_NOHUGEPAGE - mark the given range as not worth being backed by
> + * transparent huge pages so the existing pages will not be
> + * coalesced into THP and new pages will not be allocated as THP.
> + * MADV_DONTDUMP - the application wants to prevent pages in the given range
> + * from being included in its core dump.
> + * MADV_DODUMP - cancel MADV_DONTDUMP: no longer exclude from core dump.
> + *
> + * return values:
> + * zero - success
> + * -EINVAL - start + len < 0, start is not page-aligned,
> + * "behavior" is not a valid value, or application
> + * is attempting to release locked or shared pages,
> + * or the specified address range includes file, Huge TLB,
> + * MAP_SHARED or VMPFNMAP range.
> + * -ENOMEM - addresses in the specified range are not currently
> + * mapped, or are outside the AS of the process.
> + * -EIO - an I/O error occurred while paging in data.
> + * -EBADF - map exists, but area maps something that isn't a file.
> + * -EAGAIN - a kernel resource was temporarily unavailable.
> + */
> +SYSCALL_DEFINE3(madvise, unsigned long, start, size_t, len_in, int, behavior)
> +{
> + return madvise_core(current, start, len_in, behavior);
> +}
> --
> 2.21.0.1020.gf2820cf01a-goog
>
--
Best regards,
Oleksandr Natalenko (post-factum)
Senior Software Maintenance Engineer
next prev parent reply other threads:[~2019-05-20 14:26 UTC|newest]
Thread overview: 138+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-05-20 3:52 [RFC 0/7] introduce memory hinting API for external process Minchan Kim
2019-05-20 3:52 ` [RFC 1/7] mm: introduce MADV_COOL Minchan Kim
2019-05-20 8:16 ` Michal Hocko
2019-05-20 8:19 ` Michal Hocko
2019-05-20 15:08 ` Suren Baghdasaryan
2019-05-20 22:55 ` Minchan Kim
2019-05-20 22:54 ` Minchan Kim
2019-05-21 6:04 ` Michal Hocko
2019-05-21 9:11 ` Minchan Kim
2019-05-21 10:05 ` Michal Hocko
2019-05-28 8:53 ` Hillf Danton
2019-05-28 10:58 ` Minchan Kim
2019-05-20 3:52 ` [RFC 2/7] mm: change PAGEREF_RECLAIM_CLEAN with PAGE_REFRECLAIM Minchan Kim
2019-05-20 16:50 ` Johannes Weiner
2019-05-20 22:57 ` Minchan Kim
2019-05-20 3:52 ` [RFC 3/7] mm: introduce MADV_COLD Minchan Kim
2019-05-20 8:27 ` Michal Hocko
2019-05-20 23:00 ` Minchan Kim
2019-05-21 6:08 ` Michal Hocko
2019-05-21 9:13 ` Minchan Kim
2019-05-28 14:54 ` Hillf Danton
2019-05-30 0:45 ` Minchan Kim
2019-05-20 3:52 ` [RFC 4/7] mm: factor out madvise's core functionality Minchan Kim
2019-05-20 14:26 ` Oleksandr Natalenko [this message]
2019-05-21 1:26 ` Minchan Kim
2019-05-21 6:36 ` Oleksandr Natalenko
2019-05-21 6:50 ` Michal Hocko
2019-05-21 7:06 ` Oleksandr Natalenko
2019-05-21 10:52 ` Minchan Kim
2019-05-21 11:00 ` Michal Hocko
2019-05-21 11:24 ` Minchan Kim
2019-05-21 11:32 ` Michal Hocko
2019-05-21 10:49 ` Minchan Kim
2019-05-21 10:55 ` Michal Hocko
2019-05-20 3:52 ` [RFC 5/7] mm: introduce external memory hinting API Minchan Kim
2019-05-20 9:18 ` Michal Hocko
2019-05-21 2:41 ` Minchan Kim
2019-05-21 6:17 ` Michal Hocko
2019-05-21 10:32 ` Minchan Kim
2019-05-21 9:01 ` Christian Brauner
2019-05-21 11:35 ` Minchan Kim
2019-05-21 11:51 ` Christian Brauner
2019-05-21 15:31 ` Oleg Nesterov
2019-05-27 7:43 ` Minchan Kim
2019-05-27 15:12 ` Oleg Nesterov
2019-05-27 23:33 ` Minchan Kim
2019-05-28 7:23 ` Michal Hocko
2019-05-29 3:41 ` Hillf Danton
2019-05-30 0:38 ` Minchan Kim
2019-05-20 3:52 ` [RFC 6/7] mm: extend process_madvise syscall to support vector arrary Minchan Kim
2019-05-20 9:22 ` Michal Hocko
2019-05-21 2:48 ` Minchan Kim
2019-05-21 6:24 ` Michal Hocko
2019-05-21 10:26 ` Minchan Kim
2019-05-21 10:37 ` Michal Hocko
2019-05-27 7:49 ` Minchan Kim
2019-05-29 10:08 ` Daniel Colascione
2019-05-29 10:33 ` Michal Hocko
2019-05-30 2:17 ` Minchan Kim
2019-05-30 6:57 ` Michal Hocko
2019-05-30 8:02 ` Minchan Kim
2019-05-30 16:19 ` Daniel Colascione
2019-05-30 18:47 ` Michal Hocko
2019-05-29 4:14 ` Hillf Danton
2019-05-30 0:35 ` Minchan Kim
2019-05-20 3:52 ` [RFC 7/7] mm: madvise support MADV_ANONYMOUS_FILTER and MADV_FILE_FILTER Minchan Kim
2019-05-20 9:28 ` Michal Hocko
2019-05-21 2:55 ` Minchan Kim
2019-05-21 6:26 ` Michal Hocko
2019-05-27 7:58 ` Minchan Kim
2019-05-27 12:44 ` Michal Hocko
2019-05-28 3:26 ` Minchan Kim
2019-05-28 6:29 ` Michal Hocko
2019-05-28 8:13 ` Minchan Kim
2019-05-28 8:31 ` Daniel Colascione
2019-05-28 8:49 ` Minchan Kim
2019-05-28 9:08 ` Michal Hocko
2019-05-28 9:39 ` Daniel Colascione
2019-05-28 10:33 ` Michal Hocko
2019-05-28 11:21 ` Daniel Colascione
2019-05-28 11:49 ` Michal Hocko
2019-05-28 12:11 ` Daniel Colascione
2019-05-28 12:32 ` Michal Hocko
2019-05-28 10:32 ` Minchan Kim
2019-05-28 10:41 ` Michal Hocko
2019-05-28 11:12 ` Minchan Kim
2019-05-28 11:28 ` Michal Hocko
2019-05-28 11:42 ` Daniel Colascione
2019-05-28 11:56 ` Michal Hocko
2019-05-28 12:18 ` Daniel Colascione
2019-05-28 12:38 ` Michal Hocko
2019-05-28 12:10 ` Minchan Kim
2019-05-28 11:44 ` Minchan Kim
2019-05-28 11:51 ` Daniel Colascione
2019-05-28 12:06 ` Michal Hocko
2019-05-28 12:22 ` Minchan Kim
2019-05-28 11:28 ` Daniel Colascione
2019-05-21 15:33 ` Johannes Weiner
2019-05-22 1:50 ` Minchan Kim
2019-05-29 4:36 ` Hillf Danton
2019-05-30 1:00 ` Minchan Kim
2019-05-20 6:37 ` [RFC 0/7] introduce memory hinting API for external process Anshuman Khandual
2019-05-20 16:59 ` Tim Murray
2019-05-21 2:55 ` Anshuman Khandual
2019-05-21 5:14 ` Minchan Kim
2019-05-21 10:34 ` Michal Hocko
2019-05-28 10:50 ` Anshuman Khandual
2019-05-21 12:56 ` Shakeel Butt
2019-05-22 4:15 ` Brian Geffon
2019-05-22 4:23 ` Brian Geffon
2019-05-20 9:28 ` Michal Hocko
2019-05-20 14:42 ` Oleksandr Natalenko
2019-05-21 2:56 ` Minchan Kim
2019-05-20 16:46 ` Johannes Weiner
2019-05-21 4:39 ` Minchan Kim
2019-05-21 6:32 ` Michal Hocko
2019-05-21 1:44 ` Matthew Wilcox
2019-05-21 5:01 ` Minchan Kim
2019-05-21 6:34 ` Michal Hocko
2019-05-21 8:42 ` Christian Brauner
2019-05-21 11:05 ` Minchan Kim
2019-05-21 11:30 ` Christian Brauner
2019-05-21 11:39 ` Christian Brauner
2019-05-22 5:11 ` Daniel Colascione
2019-05-22 8:22 ` Christian Brauner
2019-05-22 13:16 ` Daniel Colascione
2019-05-22 14:52 ` Christian Brauner
2019-05-22 15:17 ` Daniel Colascione
2019-05-22 15:48 ` Christian Brauner
2019-05-22 15:57 ` Daniel Colascione
2019-05-22 16:01 ` Christian Brauner
2019-05-22 16:01 ` Daniel Colascione
2019-05-23 13:07 ` Minchan Kim
2019-05-27 8:06 ` Minchan Kim
2019-05-21 11:41 ` Minchan Kim
2019-05-21 12:04 ` Christian Brauner
2019-05-21 12:15 ` Oleksandr Natalenko
2019-05-21 12:53 ` Shakeel Butt
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