> -----Original Message----- > From: owner-linux-mm@xxxxxxxxx [mailto:owner-linux-mm@xxxxxxxxx] On Behalf Of Sergey > Senozhatsky > Sent: Friday, August 15, 2014 2:12 PM > To: Chao Yu > Cc: minchan@xxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; linux-mm@xxxxxxxxx; ngupta@xxxxxxxxxx; > 'Jerome Marchand'; 'Sergey Senozhatsky'; 'Andrew Morton' > Subject: Re: [PATCH] zram: add num_discards for discarded pages stat > > On (08/15/14 11:27), Chao Yu wrote: > > Now we have supported handling discard request which is sended by filesystem, > > but no interface could be used to show information of discard. > > This patch adds num_discards to stat discarded pages, then export it to sysfs > > for displaying. > > > > a side question: we account discarded pages via slot free notify in > notify_free and via req_discard in num_discards. how about accounting > both of them in num_discards? because, after all, they account a number > of discarded pages (zram_free_page()). or there any particular reason we > want to distinguish. Yeah, I agree with you as I have no such reason unless there are our users' explicitly requirement for showing notify_free/num_discards separately later. How do you think of sending another patch to merge these two counts? One more thing is that I am missing to update document of zram, sorry about that, let me update it in v2. Thanks, Yu > > -ss > > > Signed-off-by: Chao Yu <chao2.yu@xxxxxxxxxxx> > > --- > > Documentation/ABI/testing/sysfs-block-zram | 10 ++++++++++ > > drivers/block/zram/zram_drv.c | 3 +++ > > drivers/block/zram/zram_drv.h | 1 + > > 3 files changed, 14 insertions(+) > > > > diff --git a/Documentation/ABI/testing/sysfs-block-zram > b/Documentation/ABI/testing/sysfs-block-zram > > index 70ec992..fa8936e 100644 > > --- a/Documentation/ABI/testing/sysfs-block-zram > > +++ b/Documentation/ABI/testing/sysfs-block-zram > > @@ -57,6 +57,16 @@ Description: > > The failed_writes file is read-only and specifies the number of > > failed writes happened on this device. > > > > + > > +What: /sys/block/zram<id>/num_discards > > +Date: August 2014 > > +Contact: Chao Yu <chao2.yu@xxxxxxxxxxx> > > +Description: > > + The num_discards file is read-only and specifies the number of > > + physical blocks which are discarded by this device. These blocks > > + are included in discard request which is sended by filesystem as > > + the blocks are no longer used. > > + > > What: /sys/block/zram<id>/max_comp_streams > > Date: February 2014 > > Contact: Sergey Senozhatsky <sergey.senozhatsky@xxxxxxxxx> > > diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c > > index d00831c..904e7a5 100644 > > --- a/drivers/block/zram/zram_drv.c > > +++ b/drivers/block/zram/zram_drv.c > > @@ -606,6 +606,7 @@ static void zram_bio_discard(struct zram *zram, u32 index, > > bit_spin_lock(ZRAM_ACCESS, &meta->table[index].value); > > zram_free_page(zram, index); > > bit_spin_unlock(ZRAM_ACCESS, &meta->table[index].value); > > + atomic64_inc(&zram->stats.num_discards); > > index++; > > n -= PAGE_SIZE; > > } > > @@ -866,6 +867,7 @@ ZRAM_ATTR_RO(num_reads); > > ZRAM_ATTR_RO(num_writes); > > ZRAM_ATTR_RO(failed_reads); > > ZRAM_ATTR_RO(failed_writes); > > +ZRAM_ATTR_RO(num_discards); > > ZRAM_ATTR_RO(invalid_io); > > ZRAM_ATTR_RO(notify_free); > > ZRAM_ATTR_RO(zero_pages); > > @@ -879,6 +881,7 @@ static struct attribute *zram_disk_attrs[] = { > > &dev_attr_num_writes.attr, > > &dev_attr_failed_reads.attr, > > &dev_attr_failed_writes.attr, > > + &dev_attr_num_discards.attr, > > &dev_attr_invalid_io.attr, > > &dev_attr_notify_free.attr, > > &dev_attr_zero_pages.attr, > > diff --git a/drivers/block/zram/zram_drv.h b/drivers/block/zram/zram_drv.h > > index e0f725c..2994aaf 100644 > > --- a/drivers/block/zram/zram_drv.h > > +++ b/drivers/block/zram/zram_drv.h > > @@ -86,6 +86,7 @@ struct zram_stats { > > atomic64_t num_writes; /* --do-- */ > > atomic64_t failed_reads; /* can happen when memory is too low */ > > atomic64_t failed_writes; /* can happen when memory is too low */ > > + atomic64_t num_discards; /* no. of discarded pages */ > > atomic64_t invalid_io; /* non-page-aligned I/O requests */ > > atomic64_t notify_free; /* no. of swap slot free notifications */ > > atomic64_t zero_pages; /* no. of zero filled pages */ > > -- > > 2.0.1.474.g72c7794 > > > > > > -- > To unsubscribe, send a message with 'unsubscribe linux-mm' in > the body to majordomo@xxxxxxxxx. For more info on Linux MM, > see: http://www.linux-mm.org/ . > Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a> -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>