On 2020/5/7 2:43, Eric Biggers wrote: > On Wed, May 06, 2020 at 03:43:36PM +0800, Chao Yu wrote: >> On 2020/5/6 4:48, Eric Biggers wrote: >>> From: Eric Biggers <ebigg...@google.com> >>> >>> kmalloc() returns kmalloc'ed memory, and kvmalloc() returns either >>> kmalloc'ed or vmalloc'ed memory. But the f2fs wrappers, f2fs_kmalloc() >>> and f2fs_kvmalloc(), both return both kinds of memory. >>> >>> It's redundant to have two functions that do the same thing, and also >>> breaking the standard naming convention is causing bugs since people >>> assume it's safe to kfree() memory allocated by f2fs_kmalloc(). See >>> e.g. the various allocations in fs/f2fs/compress.c. >>> >>> Fix this by making f2fs_kmalloc() just use kmalloc(). And to avoid >>> re-introducing the allocation failures that the vmalloc fallback was >>> intended to fix, convert the largest allocations to use f2fs_kvmalloc(). >> >> I've submitted one patch since you suggested when commented in compression >> support patch. >> >> I remember Jaegeuk prefer to use f2fs_kvmalloc() to instead f2fs_kmalloc(), >> and keep the order of kmalloc - failed - kvmalloc. >> > > I think you're talking about > https://lkml.kernel.org/r/20191105030451.ga55...@jaegeuk-macbookpro.roam.corp.google.com? > > I think that making the large allocations use kvmalloc(), as this patch does, > is > good enough to address any memory allocation failures that may have been > encountered in the past. We don't need to switch all allocations to use > kvmalloc(), as there's no benefit for small allocations.
Yeah, I agreed, and in ENOMEM case, small-sized kvmalloc increases allocating path length unnecessarily. Thanks, > > - Eric > . > _______________________________________________ Linux-f2fs-devel mailing list Linux-f2fs-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel
