diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2022-08-23 23:33:08 +0300 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2022-08-23 23:33:08 +0300 |
commit | 95607ad99b5a4e3e69e025621165753718a6ea98 (patch) | |
tree | 6eef14ae97c6ae6bd06b8be077a180810ce164cd /drivers | |
parent | 6234806f8c9fe93f8db99cb47fc079ce78aabbd5 (diff) | |
parent | 9c80e79906b4ca440d09e7f116609262bb747909 (diff) |
Merge tag 'mm-hotfixes-stable-2022-08-22' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull misc fixes from Andrew Morton:
"Thirteen fixes, almost all for MM.
Seven of these are cc:stable and the remainder fix up the changes
which went into this -rc cycle"
* tag 'mm-hotfixes-stable-2022-08-22' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
kprobes: don't call disarm_kprobe() for disabled kprobes
mm/shmem: shmem_replace_page() remember NR_SHMEM
mm/shmem: tmpfs fallocate use file_modified()
mm/shmem: fix chattr fsflags support in tmpfs
mm/hugetlb: support write-faults in shared mappings
mm/hugetlb: fix hugetlb not supporting softdirty tracking
mm/uffd: reset write protection when unregister with wp-mode
mm/smaps: don't access young/dirty bit if pte unpresent
mm: add DEVICE_ZONE to FOR_ALL_ZONES
kernel/sys_ni: add compat entry for fadvise64_64
mm/gup: fix FOLL_FORCE COW security issue and remove FOLL_COW
Revert "zram: remove double compression logic"
get_maintainer: add Alan to .get_maintainer.ignore
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/block/zram/zram_drv.c | 42 | ||||
-rw-r--r-- | drivers/block/zram/zram_drv.h | 1 |
2 files changed, 33 insertions, 10 deletions
diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c index 92cb929a45b7..226ea76cc819 100644 --- a/drivers/block/zram/zram_drv.c +++ b/drivers/block/zram/zram_drv.c @@ -1146,14 +1146,15 @@ static ssize_t bd_stat_show(struct device *dev, static ssize_t debug_stat_show(struct device *dev, struct device_attribute *attr, char *buf) { - int version = 2; + int version = 1; struct zram *zram = dev_to_zram(dev); ssize_t ret; down_read(&zram->init_lock); ret = scnprintf(buf, PAGE_SIZE, - "version: %d\n%8llu\n", + "version: %d\n%8llu %8llu\n", version, + (u64)atomic64_read(&zram->stats.writestall), (u64)atomic64_read(&zram->stats.miss_free)); up_read(&zram->init_lock); @@ -1351,7 +1352,7 @@ static int __zram_bvec_write(struct zram *zram, struct bio_vec *bvec, { int ret = 0; unsigned long alloced_pages; - unsigned long handle = 0; + unsigned long handle = -ENOMEM; unsigned int comp_len = 0; void *src, *dst, *mem; struct zcomp_strm *zstrm; @@ -1369,6 +1370,7 @@ static int __zram_bvec_write(struct zram *zram, struct bio_vec *bvec, } kunmap_atomic(mem); +compress_again: zstrm = zcomp_stream_get(zram->comp); src = kmap_atomic(page); ret = zcomp_compress(zstrm, src, &comp_len); @@ -1377,20 +1379,39 @@ static int __zram_bvec_write(struct zram *zram, struct bio_vec *bvec, if (unlikely(ret)) { zcomp_stream_put(zram->comp); pr_err("Compression failed! err=%d\n", ret); + zs_free(zram->mem_pool, handle); return ret; } if (comp_len >= huge_class_size) comp_len = PAGE_SIZE; - - handle = zs_malloc(zram->mem_pool, comp_len, - __GFP_KSWAPD_RECLAIM | - __GFP_NOWARN | - __GFP_HIGHMEM | - __GFP_MOVABLE); - + /* + * handle allocation has 2 paths: + * a) fast path is executed with preemption disabled (for + * per-cpu streams) and has __GFP_DIRECT_RECLAIM bit clear, + * since we can't sleep; + * b) slow path enables preemption and attempts to allocate + * the page with __GFP_DIRECT_RECLAIM bit set. we have to + * put per-cpu compression stream and, thus, to re-do + * the compression once handle is allocated. + * + * if we have a 'non-null' handle here then we are coming + * from the slow path and handle has already been allocated. + */ + if (IS_ERR((void *)handle)) + handle = zs_malloc(zram->mem_pool, comp_len, + __GFP_KSWAPD_RECLAIM | + __GFP_NOWARN | + __GFP_HIGHMEM | + __GFP_MOVABLE); if (IS_ERR((void *)handle)) { zcomp_stream_put(zram->comp); + atomic64_inc(&zram->stats.writestall); + handle = zs_malloc(zram->mem_pool, comp_len, + GFP_NOIO | __GFP_HIGHMEM | + __GFP_MOVABLE); + if (!IS_ERR((void *)handle)) + goto compress_again; return PTR_ERR((void *)handle); } @@ -1948,6 +1969,7 @@ static int zram_add(void) if (ZRAM_LOGICAL_BLOCK_SIZE == PAGE_SIZE) blk_queue_max_write_zeroes_sectors(zram->disk->queue, UINT_MAX); + blk_queue_flag_set(QUEUE_FLAG_STABLE_WRITES, zram->disk->queue); ret = device_add_disk(NULL, zram->disk, zram_disk_groups); if (ret) goto out_cleanup_disk; diff --git a/drivers/block/zram/zram_drv.h b/drivers/block/zram/zram_drv.h index 158c91e54850..80c3b43b4828 100644 --- a/drivers/block/zram/zram_drv.h +++ b/drivers/block/zram/zram_drv.h @@ -81,6 +81,7 @@ struct zram_stats { atomic64_t huge_pages_since; /* no. of huge pages since zram set up */ atomic64_t pages_stored; /* no. of pages currently stored */ atomic_long_t max_used_pages; /* no. of maximum pages stored */ + atomic64_t writestall; /* no. of write slow paths */ atomic64_t miss_free; /* no. of missed free */ #ifdef CONFIG_ZRAM_WRITEBACK atomic64_t bd_count; /* no. of pages in backing device */ |