* Re: [PATCH] Writeback page range hint [not found] <200408232138.i7NLcfJd019125@hera.kernel.org> @ 2004-08-24 1:07 ` Dave Jones 2004-08-24 1:14 ` Andrew Morton 2004-08-24 1:29 ` wli 0 siblings, 2 replies; 5+ messages in thread From: Dave Jones @ 2004-08-24 1:07 UTC (permalink / raw) To: Linux Kernel Mailing List; +Cc: Andrew Morton, suparna On Mon, Aug 23, 2004 at 07:59:27PM +0000, Linux Kernel wrote: > ChangeSet 1.2034, 2004/08/23 12:59:27-07:00, akpm@osdl.org > > [PATCH] Writeback page range hint > > Modify mpage_writepages to optionally only write back dirty pages within a > specified range in a file (as in the case of O_SYNC). Cheat a little to avoid > changes to prototypes of aops - just put the <start, end> hint into the > writeback_control struct instead. If <start, end> are not set, then default > to writing back all the mapping's dirty pages. FYI, this chunk... > long pages_skipped; /* Pages which were not written */ > - int nonblocking; /* Don't get stuck on request queues */ > - int encountered_congestion; /* An output: a queue is full */ > - int for_kupdate; /* A kupdate writeback */ > - int for_reclaim; /* Invoked from the page allocator */ > + > + /* > + * For a_ops->writepages(): is start or end are non-zero then this is > + * a hint that the filesystem need only write out the pages inside that > + * byterange. The byte at `end' is included in the writeout request. > + */ > + loff_t start; > + loff_t end; > + > + int nonblocking:1; /* Don't get stuck on request queues */ > + int encountered_congestion:1; /* An output: a queue is full */ > + int for_kupdate:1; /* A kupdate writeback */ > + int for_reclaim:1; /* Invoked from the page allocator */ Causes sparse spew.. include/linux/writeback.h:54:19: warning: dubious one-bit signed bitfield include/linux/writeback.h:55:30: warning: dubious one-bit signed bitfield include/linux/writeback.h:56:19: warning: dubious one-bit signed bitfield include/linux/writeback.h:57:19: warning: dubious one-bit signed bitfield Dave ^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH] Writeback page range hint 2004-08-24 1:07 ` [PATCH] Writeback page range hint Dave Jones @ 2004-08-24 1:14 ` Andrew Morton 2004-08-24 1:18 ` Dave Jones 2004-08-24 1:29 ` wli 1 sibling, 1 reply; 5+ messages in thread From: Andrew Morton @ 2004-08-24 1:14 UTC (permalink / raw) To: Dave Jones; +Cc: linux-kernel, suparna Dave Jones <davej@redhat.com> wrote: > > FYI, this chunk... > > > long pages_skipped; /* Pages which were not written */ > > - int nonblocking; /* Don't get stuck on request queues */ > > - int encountered_congestion; /* An output: a queue is full */ > > - int for_kupdate; /* A kupdate writeback */ > > - int for_reclaim; /* Invoked from the page allocator */ > > + > > + /* > > + * For a_ops->writepages(): is start or end are non-zero then this is > > + * a hint that the filesystem need only write out the pages inside that > > + * byterange. The byte at `end' is included in the writeout request. > > + */ > > + loff_t start; > > + loff_t end; > > + > > + int nonblocking:1; /* Don't get stuck on request queues */ > > + int encountered_congestion:1; /* An output: a queue is full */ > > + int for_kupdate:1; /* A kupdate writeback */ > > + int for_reclaim:1; /* Invoked from the page allocator */ > > Causes sparse spew.. > > include/linux/writeback.h:54:19: warning: dubious one-bit signed bitfield > include/linux/writeback.h:55:30: warning: dubious one-bit signed bitfield > include/linux/writeback.h:56:19: warning: dubious one-bit signed bitfield > include/linux/writeback.h:57:19: warning: dubious one-bit signed bitfield That's fussy of it. I assume this shuts it up? --- 25/include/linux/writeback.h~writeback-sparse-warning-fix 2004-08-23 18:12:09.669385176 -0700 +++ 25-akpm/include/linux/writeback.h 2004-08-23 18:12:44.064156376 -0700 @@ -51,10 +51,10 @@ struct writeback_control { loff_t start; loff_t end; - int nonblocking:1; /* Don't get stuck on request queues */ - int encountered_congestion:1; /* An output: a queue is full */ - int for_kupdate:1; /* A kupdate writeback */ - int for_reclaim:1; /* Invoked from the page allocator */ + unsigned int nonblocking:1; /* Don't get stuck on request queues */ + unsigned int encountered_congestion:1; /* An output: a queue is full */ + unsigned int for_kupdate:1; /* A kupdate writeback */ + unsigned int for_reclaim:1; /* Invoked from the page allocator */ }; /* _ ^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH] Writeback page range hint 2004-08-24 1:14 ` Andrew Morton @ 2004-08-24 1:18 ` Dave Jones 2004-08-24 1:21 ` Andrew Morton 0 siblings, 1 reply; 5+ messages in thread From: Dave Jones @ 2004-08-24 1:18 UTC (permalink / raw) To: Andrew Morton; +Cc: linux-kernel, suparna On Mon, Aug 23, 2004 at 06:14:00PM -0700, Andrew Morton wrote: > > > + int nonblocking:1; /* Don't get stuck on request queues */ > > > + int encountered_congestion:1; /* An output: a queue is full */ > > > + int for_kupdate:1; /* A kupdate writeback */ > > > + int for_reclaim:1; /* Invoked from the page allocator */ > > > > Causes sparse spew.. > > > > include/linux/writeback.h:54:19: warning: dubious one-bit signed bitfield > > include/linux/writeback.h:55:30: warning: dubious one-bit signed bitfield > > include/linux/writeback.h:56:19: warning: dubious one-bit signed bitfield > > include/linux/writeback.h:57:19: warning: dubious one-bit signed bitfield > > That's fussy of it. I assume this shuts it up? very likely (its 2am, and I'm feeling too lazy to check). though, is there any real reason why they are bitfields at all ? I'll double check it in the morning when the nightly sparse cron jobs mail me 8-) Dave ^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH] Writeback page range hint 2004-08-24 1:18 ` Dave Jones @ 2004-08-24 1:21 ` Andrew Morton 0 siblings, 0 replies; 5+ messages in thread From: Andrew Morton @ 2004-08-24 1:21 UTC (permalink / raw) To: Dave Jones; +Cc: linux-kernel, suparna Dave Jones <davej@redhat.com> wrote: > > On Mon, Aug 23, 2004 at 06:14:00PM -0700, Andrew Morton wrote: > > > > > + int nonblocking:1; /* Don't get stuck on request queues */ > > > > + int encountered_congestion:1; /* An output: a queue is full */ > > > > + int for_kupdate:1; /* A kupdate writeback */ > > > > + int for_reclaim:1; /* Invoked from the page allocator */ > > > > > > Causes sparse spew.. > > > > > > include/linux/writeback.h:54:19: warning: dubious one-bit signed bitfield > > > include/linux/writeback.h:55:30: warning: dubious one-bit signed bitfield > > > include/linux/writeback.h:56:19: warning: dubious one-bit signed bitfield > > > include/linux/writeback.h:57:19: warning: dubious one-bit signed bitfield > > > > That's fussy of it. I assume this shuts it up? > > very likely (its 2am, and I'm feeling too lazy to check). That's the middle of the working day. > though, is there any real reason why they are bitfields at all ? That should have been in the changelog. Bad Suparna. These structures are allocated on the stack in the (deep) writeback paths. Saving a few bytes there does seem to be worth the increased code size. ^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH] Writeback page range hint 2004-08-24 1:07 ` [PATCH] Writeback page range hint Dave Jones 2004-08-24 1:14 ` Andrew Morton @ 2004-08-24 1:29 ` wli 1 sibling, 0 replies; 5+ messages in thread From: wli @ 2004-08-24 1:29 UTC (permalink / raw) To: Dave Jones, Linux Kernel Mailing List, Andrew Morton, suparna On Tue, Aug 24, 2004 at 02:07:23AM +0100, Dave Jones wrote: > Causes sparse spew.. > include/linux/writeback.h:54:19: warning: dubious one-bit signed bitfield > include/linux/writeback.h:55:30: warning: dubious one-bit signed bitfield > include/linux/writeback.h:56:19: warning: dubious one-bit signed bitfield > include/linux/writeback.h:57:19: warning: dubious one-bit signed bitfield Does this help? Index: mm4-2.6.8.1/include/linux/writeback.h =================================================================== --- mm4-2.6.8.1.orig/include/linux/writeback.h 2004-08-23 16:11:10.318739856 -0700 +++ mm4-2.6.8.1/include/linux/writeback.h 2004-08-23 18:26:45.790960088 -0700 @@ -51,10 +51,10 @@ loff_t start; loff_t end; - int nonblocking:1; /* Don't get stuck on request queues */ - int encountered_congestion:1; /* An output: a queue is full */ - int for_kupdate:1; /* A kupdate writeback */ - int for_reclaim:1; /* Invoked from the page allocator */ + unsigned nonblocking:1, /* Don't get stuck on request queues */ + encountered_congestion:1, /* An output: a queue is full */ + for_kupdate:1, /* A kupdate writeback */ + for_reclaim:1; /* Invoked from the page allocator */ }; /* ^ permalink raw reply [flat|nested] 5+ messages in thread
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[not found] <200408232138.i7NLcfJd019125@hera.kernel.org>
2004-08-24 1:07 ` [PATCH] Writeback page range hint Dave Jones
2004-08-24 1:14 ` Andrew Morton
2004-08-24 1:18 ` Dave Jones
2004-08-24 1:21 ` Andrew Morton
2004-08-24 1:29 ` wli
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