| Message ID | 20240423034643.141219-4-shikemeng@huaweicloud.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Improve visibility of writeback | expand |
on 4/23/2024 11:46 AM, Kemeng Shi wrote: > Fix two build problems: > 1. implicit declaration of function 'cgroup_ino'. > 2. unused variable 'stats'. > > After this fix, No build problem is found when CGROUPS is disabled. > The wb_stats could be successfully retrieved when CGROUP_WRITEBACK is > disabled: > cat wb_stats > WbCgIno: 1 > WbWriteback: 0 kB > WbReclaimable: 685440 kB > WbDirtyThresh: 195530960 kB > WbDirtied: 691488 kB > WbWritten: 6048 kB > WbWriteBandwidth: 102400 kBps > b_dirty: 2 > b_io: 0 > b_more_io: 0 > b_dirty_time: 0 > state: 5 > > cat wb_stats > WbCgIno: 1 > WbWriteback: 0 kB > WbReclaimable: 818944 kB > WbDirtyThresh: 195527484 kB > WbDirtied: 824992 kB > WbWritten: 6048 kB > WbWriteBandwidth: 102400 kBps > b_dirty: 2 > b_io: 0 > b_more_io: 0 > b_dirty_time: 0 > state: 5 > > Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com> Reported-by: SeongJae Park <sj@kernel.org> Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Sorry for missing reported-by tags. > --- > mm/backing-dev.c | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) > > diff --git a/mm/backing-dev.c b/mm/backing-dev.c > index 6ecd11bdce6e..e61bbb1bd622 100644 > --- a/mm/backing-dev.c > +++ b/mm/backing-dev.c > @@ -172,7 +172,11 @@ static void wb_stats_show(struct seq_file *m, struct bdi_writeback *wb, > "b_more_io: %10lu\n" > "b_dirty_time: %10lu\n" > "state: %10lx\n\n", > +#ifdef CONFIG_CGROUP_WRITEBACK > cgroup_ino(wb->memcg_css->cgroup), > +#else > + 1ul, > +#endif > K(stats->nr_writeback), > K(stats->nr_reclaimable), > K(stats->wb_thresh), > @@ -192,7 +196,6 @@ static int cgwb_debug_stats_show(struct seq_file *m, void *v) > unsigned long background_thresh; > unsigned long dirty_thresh; > struct bdi_writeback *wb; > - struct wb_stats stats; > > global_dirty_limits(&background_thresh, &dirty_thresh); > >
Hi Kemeng, On Tue, Apr 23, 2024 at 11:46:41AM +0800, Kemeng Shi wrote: > Fix two build problems: > 1. implicit declaration of function 'cgroup_ino'. I just ran into this as well, with defconfig on mm-everything: /home/hannes/src/linux/linux/mm/backing-dev.c: In function 'wb_stats_show': /home/hannes/src/linux/linux/mm/backing-dev.c:175:33: error: 'struct bdi_writeback' has no member named 'memcg_css' 175 | cgroup_ino(wb->memcg_css->cgroup), | ^~ make[3]: *** [/home/hannes/src/linux/linux/scripts/Makefile.build:244: mm/backing-dev.o] Error 1 > --- > mm/backing-dev.c | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) > > diff --git a/mm/backing-dev.c b/mm/backing-dev.c > index 6ecd11bdce6e..e61bbb1bd622 100644 > --- a/mm/backing-dev.c > +++ b/mm/backing-dev.c > @@ -172,7 +172,11 @@ static void wb_stats_show(struct seq_file *m, struct bdi_writeback *wb, > "b_more_io: %10lu\n" > "b_dirty_time: %10lu\n" > "state: %10lx\n\n", > +#ifdef CONFIG_CGROUP_WRITEBACK > cgroup_ino(wb->memcg_css->cgroup), > +#else > + 1ul, > +#endif > K(stats->nr_writeback), > K(stats->nr_reclaimable), > K(stats->wb_thresh), > @@ -192,7 +196,6 @@ static int cgwb_debug_stats_show(struct seq_file *m, void *v) > unsigned long background_thresh; > unsigned long dirty_thresh; > struct bdi_writeback *wb; > - struct wb_stats stats; > > global_dirty_limits(&background_thresh, &dirty_thresh); The fix looks right to me, but it needs to be folded into the previous patch. No patch should knowingly introduce an issue that is fixed later on. This will break bisection.
Hi Johannes, on 4/24/2024 9:27 PM, Johannes Weiner wrote: > Hi Kemeng, > > On Tue, Apr 23, 2024 at 11:46:41AM +0800, Kemeng Shi wrote: >> Fix two build problems: >> 1. implicit declaration of function 'cgroup_ino'. > > I just ran into this as well, with defconfig on mm-everything: Sorry for this. > > /home/hannes/src/linux/linux/mm/backing-dev.c: In function 'wb_stats_show': > /home/hannes/src/linux/linux/mm/backing-dev.c:175:33: error: 'struct bdi_writeback' has no member named 'memcg_css' > 175 | cgroup_ino(wb->memcg_css->cgroup), > | ^~ > make[3]: *** [/home/hannes/src/linux/linux/scripts/Makefile.build:244: mm/backing-dev.o] Error 1 > >> --- >> mm/backing-dev.c | 5 ++++- >> 1 file changed, 4 insertions(+), 1 deletion(-) >> >> diff --git a/mm/backing-dev.c b/mm/backing-dev.c >> index 6ecd11bdce6e..e61bbb1bd622 100644 >> --- a/mm/backing-dev.c >> +++ b/mm/backing-dev.c >> @@ -172,7 +172,11 @@ static void wb_stats_show(struct seq_file *m, struct bdi_writeback *wb, >> "b_more_io: %10lu\n" >> "b_dirty_time: %10lu\n" >> "state: %10lx\n\n", >> +#ifdef CONFIG_CGROUP_WRITEBACK >> cgroup_ino(wb->memcg_css->cgroup), >> +#else >> + 1ul, >> +#endif >> K(stats->nr_writeback), >> K(stats->nr_reclaimable), >> K(stats->wb_thresh), >> @@ -192,7 +196,6 @@ static int cgwb_debug_stats_show(struct seq_file *m, void *v) >> unsigned long background_thresh; >> unsigned long dirty_thresh; >> struct bdi_writeback *wb; >> - struct wb_stats stats; >> >> global_dirty_limits(&background_thresh, &dirty_thresh); > > The fix looks right to me, but it needs to be folded into the previous > patch. No patch should knowingly introduce an issue that is fixed > later on. This will break bisection. As I'm not sure if previous patch is already applied to tree, so I make this fix a individual patch and mentioned in cover letter that this could be folded if previous patch is not in tree or this could be applied individually to fix the introduced issue. As Androw told me that little fixups would be preferred instead of entire resend in current stage, I guess a new series with this patch foled should not be necessary. If a new series is still needed, please let me konw. I would like to it. Thanks.
diff --git a/mm/backing-dev.c b/mm/backing-dev.c index 6ecd11bdce6e..e61bbb1bd622 100644 --- a/mm/backing-dev.c +++ b/mm/backing-dev.c @@ -172,7 +172,11 @@ static void wb_stats_show(struct seq_file *m, struct bdi_writeback *wb, "b_more_io: %10lu\n" "b_dirty_time: %10lu\n" "state: %10lx\n\n", +#ifdef CONFIG_CGROUP_WRITEBACK cgroup_ino(wb->memcg_css->cgroup), +#else + 1ul, +#endif K(stats->nr_writeback), K(stats->nr_reclaimable), K(stats->wb_thresh), @@ -192,7 +196,6 @@ static int cgwb_debug_stats_show(struct seq_file *m, void *v) unsigned long background_thresh; unsigned long dirty_thresh; struct bdi_writeback *wb; - struct wb_stats stats; global_dirty_limits(&background_thresh, &dirty_thresh);
Fix two build problems: 1. implicit declaration of function 'cgroup_ino'. 2. unused variable 'stats'. After this fix, No build problem is found when CGROUPS is disabled. The wb_stats could be successfully retrieved when CGROUP_WRITEBACK is disabled: cat wb_stats WbCgIno: 1 WbWriteback: 0 kB WbReclaimable: 685440 kB WbDirtyThresh: 195530960 kB WbDirtied: 691488 kB WbWritten: 6048 kB WbWriteBandwidth: 102400 kBps b_dirty: 2 b_io: 0 b_more_io: 0 b_dirty_time: 0 state: 5 cat wb_stats WbCgIno: 1 WbWriteback: 0 kB WbReclaimable: 818944 kB WbDirtyThresh: 195527484 kB WbDirtied: 824992 kB WbWritten: 6048 kB WbWriteBandwidth: 102400 kBps b_dirty: 2 b_io: 0 b_more_io: 0 b_dirty_time: 0 state: 5 Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com> --- mm/backing-dev.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)