The patch titled
Subject: zram: add pages_per_pool_page device attribute
has been added to the -mm mm-unstable branch. Its filename is
zram-add-pages_per_pool_page-device-attribute.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/zram-add-pages_per_pool_page-device-attribute.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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 via the mm-everything
branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
and is updated there every 2-3 working days
------------------------------------------------------
From: Sergey Senozhatsky <senozhatsky@xxxxxxxxxxxx>
Subject: zram: add pages_per_pool_page device attribute
Date: Thu, 27 Oct 2022 13:26:49 +0900
Add a new sysfs knob that allows user-space to set zsmalloc pages
per-zspage limit value on per-device basis.
Link: https://lkml.kernel.org/r/20221027042651.234524-8-senozhatsky@xxxxxxxxxxxx
Signed-off-by: Sergey Senozhatsky <senozhatsky@xxxxxxxxxxxx>
Cc: Alexey Romanov <avromanov@xxxxxxxxxxxxxx>
Cc: Minchan Kim <minchan@xxxxxxxxxx>
Cc: Nitin Gupta <ngupta@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
--- a/drivers/block/zram/zram_drv.c~zram-add-pages_per_pool_page-device-attribute
+++ a/drivers/block/zram/zram_drv.c
@@ -1180,6 +1180,45 @@ static ssize_t mm_stat_show(struct devic
return ret;
}
+static ssize_t pages_per_pool_page_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ u32 val;
+ struct zram *zram = dev_to_zram(dev);
+
+ down_read(&zram->init_lock);
+ val = zram->pages_per_pool_page;
+ up_read(&zram->init_lock);
+
+ return scnprintf(buf, PAGE_SIZE, "%d\n", val);
+}
+
+static ssize_t pages_per_pool_page_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t len)
+{
+ struct zram *zram = dev_to_zram(dev);
+ u32 val;
+
+ if (kstrtou32(buf, 10, &val))
+ return -EINVAL;
+
+ if (val < ZS_MIN_PAGES_PER_ZSPAGE || val > ZS_MAX_PAGES_PER_ZSPAGE)
+ return -EINVAL;
+
+ down_read(&zram->init_lock);
+ if (init_done(zram)) {
+ up_read(&zram->init_lock);
+ return -EINVAL;
+ }
+
+ zram->pages_per_pool_page = val;
+ up_read(&zram->init_lock);
+
+ return len;
+}
+
#ifdef CONFIG_ZRAM_WRITEBACK
#define FOUR_K(x) ((x) * (1 << (PAGE_SHIFT - 12)))
static ssize_t bd_stat_show(struct device *dev,
@@ -1248,7 +1287,7 @@ static bool zram_meta_alloc(struct zram
return false;
zram->mem_pool = zs_create_pool(zram->disk->disk_name,
- ZS_DEFAULT_PAGES_PER_ZSPAGE);
+ zram->pages_per_pool_page);
if (!zram->mem_pool) {
vfree(zram->table);
return false;
@@ -2174,6 +2213,7 @@ static DEVICE_ATTR_RW(writeback_limit_en
static DEVICE_ATTR_RW(recomp_algorithm);
static DEVICE_ATTR_WO(recompress);
#endif
+static DEVICE_ATTR_RW(pages_per_pool_page);
static struct attribute *zram_disk_attrs[] = {
&dev_attr_disksize.attr,
@@ -2201,6 +2241,7 @@ static struct attribute *zram_disk_attrs
&dev_attr_recomp_algorithm.attr,
&dev_attr_recompress.attr,
#endif
+ &dev_attr_pages_per_pool_page.attr,
NULL,
};
@@ -2238,6 +2279,7 @@ static int zram_add(void)
goto out_free_idr;
}
+ zram->pages_per_pool_page = ZS_DEFAULT_PAGES_PER_ZSPAGE;
zram->disk->major = zram_major;
zram->disk->first_minor = device_id;
zram->disk->minors = 1;
--- a/drivers/block/zram/zram_drv.h~zram-add-pages_per_pool_page-device-attribute
+++ a/drivers/block/zram/zram_drv.h
@@ -120,6 +120,8 @@ struct zram {
*/
u64 disksize; /* bytes */
const char *comp_algs[ZRAM_MAX_ZCOMPS];
+
+ u32 pages_per_pool_page;
/*
* Pages that compress to sizes equal or greater than this are stored
* uncompressed in memory.
_
Patches currently in -mm which might be from senozhatsky@xxxxxxxxxxxx are
zram-preparation-for-multi-zcomp-support.patch
zram-add-recompression-algorithm-sysfs-knob.patch
zram-factor-out-wb-and-non-wb-zram-read-functions.patch
zram-introduce-recompress-sysfs-knob.patch
documentation-add-recompression-documentation.patch
zram-add-recompression-algorithm-choice-to-kconfig.patch
zram-add-recompress-flag-to-read_block_state.patch
zram-clarify-writeback_store-comment.patch
zram-use-is_err_value-to-check-for-zs_malloc-errors.patch
zsmalloc-turn-zspage-order-into-runtime-variable.patch
zsmalloc-move-away-from-page-order-defines.patch
zsmalloc-make-huge-class-watermark-zs_pool-member.patch
zram-huge-size-watermark-cannot-be-global.patch
zsmalloc-pass-limit-on-pages-per-zspage-to-zs_create_pool.patch
zram-add-pages_per_pool_page-device-attribute.patch
documentation-document-zram-pages_per_pool_page-attribute.patch
zsmalloc-break-out-of-loop-when-found-perfect-zspage-order.patch
