* Pavel Emelyanov ([EMAIL PROTECTED]) wrote: > Some time ago I posted a set of patches that consolidated > the seq files, walking the list_head-s. This set was merged > in the mm tree. /proc/diskstats and /proc/partitions files > were included in this set, but a bit later this part was > dropped because of conflicts with some other changes. > > Here's the fixed version against the latest git block repo. >
Hi Pavel, You might want to try implementing this patch on top of the sorted seq list patch I proposed there. It deals with a race between proc file read and list modification between iterations. http://lkml.org/lkml/2007/9/6/175 See this patch for a user implementation example and test code (/proc/modules) : http://lkml.org/lkml/2007/9/6/176 Mathieu > Signed-off-by: Pavel Emelyanov <[EMAIL PROTECTED]> > > --- > > diff --git a/block/genhd.c b/block/genhd.c > index 3af1e7a..27f7061 100644 > --- a/block/genhd.c > +++ b/block/genhd.c > @@ -264,39 +264,34 @@ void __init printk_all_partitions(void) > > #ifdef CONFIG_PROC_FS > /* iterator */ > -static void *part_start(struct seq_file *part, loff_t *pos) > +static void *disk_start(struct seq_file *part, loff_t *pos) > { > - struct list_head *p; > - loff_t l = *pos; > - > mutex_lock(&block_subsys_lock); > - list_for_each(p, &block_subsys.list) > - if (!l--) > - return list_entry(p, struct gendisk, kobj.entry); > - return NULL; > + return seq_list_start_head(&block_subsys.list, *pos); > } > > -static void *part_next(struct seq_file *part, void *v, loff_t *pos) > +static void *disk_next(struct seq_file *part, void *v, loff_t *pos) > { > - struct list_head *p = ((struct gendisk *)v)->kobj.entry.next; > - ++*pos; > - return p==&block_subsys.list ? NULL : > - list_entry(p, struct gendisk, kobj.entry); > + return seq_list_next(v, &block_subsys.list, pos); > } > > -static void part_stop(struct seq_file *part, void *v) > +static void disk_stop(struct seq_file *part, void *v) > { > mutex_unlock(&block_subsys_lock); > } > > static int show_partition(struct seq_file *part, void *v) > { > - struct gendisk *sgp = v; > + struct gendisk *sgp; > int n; > char buf[BDEVNAME_SIZE]; > > - if (&sgp->kobj.entry == block_subsys.list.next) > + if (v == &block_subsys.list) { > seq_puts(part, "major minor #blocks name\n\n"); > + return 0; > + } > + > + sgp = list_entry(v, struct gendisk, kobj.entry); > > /* Don't show non-partitionable removeable devices or empty devices */ > if (!get_capacity(sgp) || > @@ -325,9 +320,9 @@ static int show_partition(struct seq_fil > } > > struct seq_operations partitions_op = { > - .start =part_start, > - .next = part_next, > - .stop = part_stop, > + .start =disk_start, > + .next = disk_next, > + .stop = disk_stop, > .show = show_partition > }; > #endif > @@ -616,44 +611,22 @@ decl_subsys(block, &ktype_block, &block_ > */ > > /* iterator */ > -static void *diskstats_start(struct seq_file *part, loff_t *pos) > -{ > - loff_t k = *pos; > - struct list_head *p; > - > - mutex_lock(&block_subsys_lock); > - list_for_each(p, &block_subsys.list) > - if (!k--) > - return list_entry(p, struct gendisk, kobj.entry); > - return NULL; > -} > - > -static void *diskstats_next(struct seq_file *part, void *v, loff_t *pos) > -{ > - struct list_head *p = ((struct gendisk *)v)->kobj.entry.next; > - ++*pos; > - return p==&block_subsys.list ? NULL : > - list_entry(p, struct gendisk, kobj.entry); > -} > - > -static void diskstats_stop(struct seq_file *part, void *v) > -{ > - mutex_unlock(&block_subsys_lock); > -} > - > static int diskstats_show(struct seq_file *s, void *v) > { > - struct gendisk *gp = v; > + struct gendisk *gp; > char buf[BDEVNAME_SIZE]; > int n = 0; > > + if (v == &block_subsys.list) > /* > - if (&sgp->kobj.entry == block_subsys.kset.list.next) > seq_puts(s, "major minor name" > " rio rmerge rsect ruse wio wmerge " > "wsect wuse running use aveq" > "\n\n"); > */ > + return 0; > + > + gp = list_entry(v, struct gendisk, kobj.entry); > > preempt_disable(); > disk_round_stats(gp); > @@ -686,9 +659,9 @@ static int diskstats_show(struct seq_fil > } > > struct seq_operations diskstats_op = { > - .start = diskstats_start, > - .next = diskstats_next, > - .stop = diskstats_stop, > + .start = disk_start, > + .next = disk_next, > + .stop = disk_stop, > .show = diskstats_show > }; > > - > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to [EMAIL PROTECTED] > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ > -- Mathieu Desnoyers Computer Engineering Ph.D. Student, Ecole Polytechnique de Montreal OpenPGP key fingerprint: 8CD5 52C3 8E3C 4140 715F BA06 3F25 A8FE 3BAE 9A68 - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
