The patch titled
Subject: lib/test_hmm.c: remove unused dmirror_zero_page
has been added to the -mm tree. Its filename is
hmm-test-remove-unused-dmirror_zero_page.patch
This patch should soon appear at
https://ozlabs.org/~akpm/mmots/broken-out/hmm-test-remove-unused-dmirror_zero_page.patch
and later at
https://ozlabs.org/~akpm/mmotm/broken-out/hmm-test-remove-unused-dmirror_zero_page.patch
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next and is updated
there every 3-4 working days
------------------------------------------------------
From: Ralph Campbell <rcampbell@xxxxxxxxxx>
Subject: lib/test_hmm.c: remove unused dmirror_zero_page
The variable dmirror_zero_page is unused in the HMM self test driver which
was probably intended to demonstrate how a driver could use
migrate_vma_setup() to share a single read-only device private zero page
similar to how the CPU does. However, this isn't needed for the self
tests so remove it.
Link: https://lkml.kernel.org/r/20200914213801.16520-1-rcampbell@xxxxxxxxxx
Signed-off-by: Ralph Campbell <rcampbell@xxxxxxxxxx>
Cc: Jerome Glisse <jglisse@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
lib/test_hmm.c | 14 --------------
1 file changed, 14 deletions(-)
--- a/lib/test_hmm.c~hmm-test-remove-unused-dmirror_zero_page
+++ a/lib/test_hmm.c
@@ -36,7 +36,6 @@
static const struct dev_pagemap_ops dmirror_devmem_ops;
static const struct mmu_interval_notifier_ops dmirror_min_ops;
static dev_t dmirror_dev;
-static struct page *dmirror_zero_page;
struct dmirror_device;
@@ -1127,17 +1126,6 @@ static int __init hmm_dmirror_init(void)
goto err_chrdev;
}
- /*
- * Allocate a zero page to simulate a reserved page of device private
- * memory which is always zero. The zero_pfn page isn't used just to
- * make the code here simpler (i.e., we need a struct page for it).
- */
- dmirror_zero_page = alloc_page(GFP_HIGHUSER | __GFP_ZERO);
- if (!dmirror_zero_page) {
- ret = -ENOMEM;
- goto err_chrdev;
- }
-
pr_info("HMM test module loaded. This is only for testing HMM.\n");
return 0;
@@ -1153,8 +1141,6 @@ static void __exit hmm_dmirror_exit(void
{
int id;
- if (dmirror_zero_page)
- __free_page(dmirror_zero_page);
for (id = 0; id < DMIRROR_NDEVICES; id++)
dmirror_device_remove(dmirror_devices + id);
unregister_chrdev_region(dmirror_dev, DMIRROR_NDEVICES);
_
Patches currently in -mm which might be from rcampbell@xxxxxxxxxx are
mm-thp-fix-__split_huge_pmd_locked-for-migration-pmd.patch
mm-test-use-the-new-skip-macro.patch
hmm-test-remove-unused-dmirror_zero_page.patch
mm-migrate-remove-cpages-in-migrate_vma_finalize.patch
mm-migrate-remove-obsolete-comment-about-device-public.patch
