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djwong@kernel.org, pavel@kernel.org, peterz@infradead.org, mingo@redhat.com, will@kernel.org, boqun.feng@gmail.com Date: Fri, 28 Mar 2025 08:38:55 -0400 In-Reply-To: <20250328-estrich-kaleidoskop-c677a5a3f551@brauner> References: <20250327140613.25178-1-James.Bottomley@HansenPartnership.com> <20250327140613.25178-4-James.Bottomley@HansenPartnership.com> <20250328-estrich-kaleidoskop-c677a5a3f551@brauner> Autocrypt: addr=James.Bottomley@HansenPartnership.com; prefer-encrypt=mutual; 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 8mT2Eh9SkH+YVOmaKsajgZgrBxA7fWmGoxXswEVxJIFj3vW7yNc0C5HaUdYa5iGOMs4kg2ht4s7yy7NRQuh7BifWjo6BQ6k4S1H+6axZucxhSV1L6zN9d+lr3Xo/vy1unzA== Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.50.3 Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 On Fri, 2025-03-28 at 12:56 +0100, Christian Brauner wrote: > On Thu, Mar 27, 2025 at 10:06:12AM -0400, James Bottomley wrote: > > Originally proposed by Amir as an extract from the android kernel: > >=20 > > https://lore.kernel.org/linux-fsdevel/CAA2m6vfatWKS1CQFpaRbii2AXiZFvQUj= VvYhGxWTSpz+2rxDyg@mail.gmail.com/ > >=20 > > Since suspend/resume requires a reverse iterator, I'm dusting it > > off. > >=20 > > Signed-off-by: James Bottomley > > > > --- > > =C2=A0fs/super.c | 48 +++++++++++++++++++++++++++++------------------- > > =C2=A01 file changed, 29 insertions(+), 19 deletions(-) > >=20 > > diff --git a/fs/super.c b/fs/super.c > > index 5a7db4a556e3..76785509d906 100644 > > --- a/fs/super.c > > +++ b/fs/super.c > > @@ -887,28 +887,38 @@ void drop_super_exclusive(struct super_block > > *sb) > > =C2=A0} > > =C2=A0EXPORT_SYMBOL(drop_super_exclusive); > > =C2=A0 > > +#define ITERATE_SUPERS(f, rev) \ >=20 > I'm not fond of the macro magic here. > I've taken some of your patches and massaging them. I'm not either, so if you have an alternative, I'm all ears. The problem I had is that list_for_each_entry() and _reverse are designed to take a code block, so it's very difficult to swap one for the other without macroizing. The internal logic is complex enough that I didn't want to duplicate it. Regards, James