From: Steven Rostedt <rostedt@goodmis.org>
To: LKML <linux-kernel@vger.kernel.org>
Cc: Ben Skeggs <bskeggs@redhat.com>, David Airlie <airlied@linux.ie>,
Daniel Vetter <daniel@ffwll.ch>,
Leon Romanovsky <leon@kernel.org>,
Doug Ledford <dledford@redhat.com>,
Jason Gunthorpe <jgg@ziepe.ca>,
"Darrick J. Wong" <darrick.wong@oracle.com>,
linux-xfs@vger.kernel.org, dri-devel@lists.freedesktop.org,
nouveau@lists.freedesktop.org, linux-rdma@vger.kernel.org,
Linus Torvalds <torvalds@linux-foundation.org>,
Andrew Morton <akpm@linux-foundation.org>
Subject: [RFC][PATCH] kernel.h: Add generic roundup_64() macro
Date: Thu, 23 May 2019 10:00:13 -0400 [thread overview]
Message-ID: <20190523100013.52a8d2a6@gandalf.local.home> (raw)
From: Steven Rostedt (VMware) <rostedt@goodmis.org>
In discussing a build failure on x86_32 due to the use of roundup() on
a 64 bit number, I realized that there's no generic equivalent
roundup_64(). It is implemented in two separate places in the kernel,
but there really should be just one that all can use.
Although the other implementations are a static inline function, this
implementation is a macro to allow the use of typeof(x) to denote the
type that is being used. If the build is on a 64 bit machine, then the
roundup_64() macro will just default back to roundup(). But for 32 bit
machines, it will use the version that is will not cause issues with
dividing a 64 bit number on a 32 bit machine.
Link: http://lkml.kernel.org/r/20190522145450.25ff483d@gandalf.local.home
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
---
diff --git a/drivers/gpu/drm/nouveau/nouveau_bo.c b/drivers/gpu/drm/nouveau/nouveau_bo.c
index 34a998012bf6..cdacfe1f732c 100644
--- a/drivers/gpu/drm/nouveau/nouveau_bo.c
+++ b/drivers/gpu/drm/nouveau/nouveau_bo.c
@@ -143,14 +143,6 @@ nouveau_bo_del_ttm(struct ttm_buffer_object *bo)
kfree(nvbo);
}
-static inline u64
-roundup_64(u64 x, u32 y)
-{
- x += y - 1;
- do_div(x, y);
- return x * y;
-}
-
static void
nouveau_bo_fixup_align(struct nouveau_bo *nvbo, u32 flags,
int *align, u64 *size)
diff --git a/fs/xfs/xfs_linux.h b/fs/xfs/xfs_linux.h
index edbd5a210df2..13de9d49bd52 100644
--- a/fs/xfs/xfs_linux.h
+++ b/fs/xfs/xfs_linux.h
@@ -207,13 +207,6 @@ static inline xfs_dev_t linux_to_xfs_dev_t(dev_t dev)
#define xfs_sort(a,n,s,fn) sort(a,n,s,fn,NULL)
#define xfs_stack_trace() dump_stack()
-static inline uint64_t roundup_64(uint64_t x, uint32_t y)
-{
- x += y - 1;
- do_div(x, y);
- return x * y;
-}
-
static inline uint64_t howmany_64(uint64_t x, uint32_t y)
{
x += y - 1;
diff --git a/include/linux/kernel.h b/include/linux/kernel.h
index 74b1ee9027f5..cd0063629357 100644
--- a/include/linux/kernel.h
+++ b/include/linux/kernel.h
@@ -115,6 +115,20 @@
(((x) + (__y - 1)) / __y) * __y; \
} \
)
+
+#if BITS_PER_LONG == 32
+# define roundup_64(x, y) ( \
+{ \
+ typeof(y) __y = y; \
+ typeof(x) __x = (x) + (__y - 1); \
+ do_div(__x, __y); \
+ __x * __y; \
+} \
+)
+#else
+# define roundup_64(x, y) roundup(x, y)
+#endif
+
/**
* rounddown - round down to next specified multiple
* @x: the value to round
next reply other threads:[~2019-05-23 14:00 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-05-23 14:00 Steven Rostedt [this message]
2019-05-23 15:10 ` [RFC][PATCH] kernel.h: Add generic roundup_64() macro Linus Torvalds
2019-05-23 15:27 ` Steven Rostedt
2019-05-23 16:51 ` Linus Torvalds
2019-05-23 17:36 ` Steven Rostedt
2019-05-23 21:19 ` Linus Torvalds
2019-05-24 15:11 ` Roger Willcocks
2019-05-24 15:26 ` Steven Rostedt
2019-05-24 16:30 ` Nikolay Borisov
2019-05-24 16:36 ` Steven Rostedt
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20190523100013.52a8d2a6@gandalf.local.home \
--to=rostedt@goodmis.org \
--cc=airlied@linux.ie \
--cc=akpm@linux-foundation.org \
--cc=bskeggs@redhat.com \
--cc=daniel@ffwll.ch \
--cc=darrick.wong@oracle.com \
--cc=dledford@redhat.com \
--cc=dri-devel@lists.freedesktop.org \
--cc=jgg@ziepe.ca \
--cc=leon@kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-rdma@vger.kernel.org \
--cc=linux-xfs@vger.kernel.org \
--cc=nouveau@lists.freedesktop.org \
--cc=torvalds@linux-foundation.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).