Re: [PATCH RFC PKS/PMEM 22/58] fs/f2fs: Utilize new kmap_thread()

2020-10-12 Thread Ira Weiny
On Mon, Oct 12, 2020 at 09:02:54PM +0100, Matthew Wilcox wrote: > On Mon, Oct 12, 2020 at 12:53:54PM -0700, Ira Weiny wrote: > > On Mon, Oct 12, 2020 at 05:44:38PM +0100, Matthew Wilcox wrote: > > > On Mon, Oct 12, 2020 at 09:28:29AM -0700, Dave Hansen wrote: > > > > kmap_atomic() is always preferr

Re: [PATCH RFC PKS/PMEM 22/58] fs/f2fs: Utilize new kmap_thread()

2020-10-12 Thread Matthew Wilcox
On Mon, Oct 12, 2020 at 12:53:54PM -0700, Ira Weiny wrote: > On Mon, Oct 12, 2020 at 05:44:38PM +0100, Matthew Wilcox wrote: > > On Mon, Oct 12, 2020 at 09:28:29AM -0700, Dave Hansen wrote: > > > kmap_atomic() is always preferred over kmap()/kmap_thread(). > > > kmap_atomic() is _much_ more lightwe

Re: [PATCH RFC PKS/PMEM 22/58] fs/f2fs: Utilize new kmap_thread()

2020-10-12 Thread Ira Weiny
On Mon, Oct 12, 2020 at 05:44:38PM +0100, Matthew Wilcox wrote: > On Mon, Oct 12, 2020 at 09:28:29AM -0700, Dave Hansen wrote: > > kmap_atomic() is always preferred over kmap()/kmap_thread(). > > kmap_atomic() is _much_ more lightweight since its TLB invalidation is > > always CPU-local and never b

Re: [PATCH RFC PKS/PMEM 22/58] fs/f2fs: Utilize new kmap_thread()

2020-10-12 Thread Matthew Wilcox
On Mon, Oct 12, 2020 at 09:28:29AM -0700, Dave Hansen wrote: > kmap_atomic() is always preferred over kmap()/kmap_thread(). > kmap_atomic() is _much_ more lightweight since its TLB invalidation is > always CPU-local and never broadcast. > > So, basically, unless you *must* sleep while the mapping

Re: [PATCH RFC PKS/PMEM 22/58] fs/f2fs: Utilize new kmap_thread()

2020-10-12 Thread Dave Hansen
On 10/12/20 9:19 AM, Eric Biggers wrote: > On Sun, Oct 11, 2020 at 11:56:35PM -0700, Ira Weiny wrote: >>> And I still don't really understand. After this patchset, there is still >>> code >>> nearly identical to the above (doing a temporary mapping just for a memcpy) >>> that >>> would still be

Re: [PATCH RFC PKS/PMEM 22/58] fs/f2fs: Utilize new kmap_thread()

2020-10-12 Thread Eric Biggers
On Sun, Oct 11, 2020 at 11:56:35PM -0700, Ira Weiny wrote: > > > > And I still don't really understand. After this patchset, there is still > > code > > nearly identical to the above (doing a temporary mapping just for a memcpy) > > that > > would still be using kmap_atomic(). > > I don't unde

Re: [PATCH RFC PKS/PMEM 22/58] fs/f2fs: Utilize new kmap_thread()

2020-10-11 Thread Ira Weiny
On Fri, Oct 09, 2020 at 06:30:36PM -0700, Eric Biggers wrote: > On Sat, Oct 10, 2020 at 01:39:54AM +0100, Matthew Wilcox wrote: > > On Fri, Oct 09, 2020 at 02:34:34PM -0700, Eric Biggers wrote: > > > On Fri, Oct 09, 2020 at 12:49:57PM -0700, ira.we...@intel.com wrote: > > > > The kmap() calls in th

Re: [PATCH RFC PKS/PMEM 22/58] fs/f2fs: Utilize new kmap_thread()

2020-10-09 Thread James Bottomley
On Fri, 2020-10-09 at 14:34 -0700, Eric Biggers wrote: > On Fri, Oct 09, 2020 at 12:49:57PM -0700, ira.we...@intel.com wrote: > > From: Ira Weiny > > > > The kmap() calls in this FS are localized to a single thread. To > > avoid the over head of global PKRS updates use the new > > kmap_thread()

Re: [PATCH RFC PKS/PMEM 22/58] fs/f2fs: Utilize new kmap_thread()

2020-10-09 Thread Eric Biggers
On Sat, Oct 10, 2020 at 01:39:54AM +0100, Matthew Wilcox wrote: > On Fri, Oct 09, 2020 at 02:34:34PM -0700, Eric Biggers wrote: > > On Fri, Oct 09, 2020 at 12:49:57PM -0700, ira.we...@intel.com wrote: > > > The kmap() calls in this FS are localized to a single thread. To avoid > > > the over head

Re: [PATCH RFC PKS/PMEM 22/58] fs/f2fs: Utilize new kmap_thread()

2020-10-09 Thread Matthew Wilcox
On Fri, Oct 09, 2020 at 02:34:34PM -0700, Eric Biggers wrote: > On Fri, Oct 09, 2020 at 12:49:57PM -0700, ira.we...@intel.com wrote: > > The kmap() calls in this FS are localized to a single thread. To avoid > > the over head of global PKRS updates use the new kmap_thread() call. > > > > @@ -2410,

Re: [PATCH RFC PKS/PMEM 22/58] fs/f2fs: Utilize new kmap_thread()

2020-10-09 Thread Eric Biggers
On Fri, Oct 09, 2020 at 12:49:57PM -0700, ira.we...@intel.com wrote: > From: Ira Weiny > > The kmap() calls in this FS are localized to a single thread. To avoid > the over head of global PKRS updates use the new kmap_thread() call. > > Cc: Jaegeuk Kim > Cc: Chao Yu > Signed-off-by: Ira Weiny

[PATCH RFC PKS/PMEM 22/58] fs/f2fs: Utilize new kmap_thread()

2020-10-09 Thread ira . weiny
From: Ira Weiny The kmap() calls in this FS are localized to a single thread. To avoid the over head of global PKRS updates use the new kmap_thread() call. Cc: Jaegeuk Kim Cc: Chao Yu Signed-off-by: Ira Weiny --- fs/f2fs/f2fs.h | 8 1 file changed, 4 insertions(+), 4 deletions(-)