| Message ID | 1606318341-29521-1-git-send-email-charante@codeaurora.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | mm: cma: improve pr_debug log in cma_release() | expand |
On Wed, Nov 25, 2020 at 9:02 PM Charan Teja Reddy <charante@codeaurora.org> wrote: > > It is required to print 'count' of pages, along with the pages, passed > to cma_release to debug the cases of mismatched count value passed > between cma_alloc() and cma_release() from a code path. > > As an example, consider the below scenario: > 1) CMA pool size is 4MB and > 2) User doing the erroneous step of allocating 2 pages but freeing 1 > page in a loop from this CMA pool. > The step 2 causes cma_alloc() to return NULL at one point of time > because of -ENOMEM condition. > > And the current pr_debug logs is not giving the info about these types > of allocation patterns because of count value not being printed in > cma_release(). > > We are printing the count value in the trace logs, just extend the same > to pr_debug logs too. > > Signed-off-by: Charan Teja Reddy <charante@codeaurora.org> Reviewed-by: Souptick Joarder <jrdr.linux@gmail.com> > --- > mm/cma.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/mm/cma.c b/mm/cma.c > index 7f415d7..07c904b 100644 > --- a/mm/cma.c > +++ b/mm/cma.c > @@ -512,7 +512,7 @@ bool cma_release(struct cma *cma, const struct page *pages, unsigned int count) > if (!cma || !pages) > return false; > > - pr_debug("%s(page %p)\n", __func__, (void *)pages); > + pr_debug("%s(page %p, count %zu)\n", __func__, (void *)pages, count); > > pfn = page_to_pfn(pages); > > -- > QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a > member of the Code Aurora Forum, hosted by The Linux Foundation > >
On 25.11.20 16:32, Charan Teja Reddy wrote: > It is required to print 'count' of pages, along with the pages, passed > to cma_release to debug the cases of mismatched count value passed > between cma_alloc() and cma_release() from a code path. > > As an example, consider the below scenario: > 1) CMA pool size is 4MB and > 2) User doing the erroneous step of allocating 2 pages but freeing 1 > page in a loop from this CMA pool. > The step 2 causes cma_alloc() to return NULL at one point of time > because of -ENOMEM condition. > > And the current pr_debug logs is not giving the info about these types > of allocation patterns because of count value not being printed in > cma_release(). > > We are printing the count value in the trace logs, just extend the same > to pr_debug logs too. > > Signed-off-by: Charan Teja Reddy <charante@codeaurora.org> > --- > mm/cma.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/mm/cma.c b/mm/cma.c > index 7f415d7..07c904b 100644 > --- a/mm/cma.c > +++ b/mm/cma.c > @@ -512,7 +512,7 @@ bool cma_release(struct cma *cma, const struct page *pages, unsigned int count) > if (!cma || !pages) > return false; > > - pr_debug("%s(page %p)\n", __func__, (void *)pages); > + pr_debug("%s(page %p, count %zu)\n", __func__, (void *)pages, count); > > pfn = page_to_pfn(pages); > > Reviewed-by: David Hildenbrand <david@redhat.com>
On 11/25/20 4:32 PM, Charan Teja Reddy wrote: > It is required to print 'count' of pages, along with the pages, passed > to cma_release to debug the cases of mismatched count value passed > between cma_alloc() and cma_release() from a code path. > > As an example, consider the below scenario: > 1) CMA pool size is 4MB and > 2) User doing the erroneous step of allocating 2 pages but freeing 1 > page in a loop from this CMA pool. > The step 2 causes cma_alloc() to return NULL at one point of time > because of -ENOMEM condition. > > And the current pr_debug logs is not giving the info about these types > of allocation patterns because of count value not being printed in > cma_release(). > > We are printing the count value in the trace logs, just extend the same > to pr_debug logs too. > > Signed-off-by: Charan Teja Reddy <charante@codeaurora.org> Acked-by: Vlastimil Babka <vbabka@suse.cz> > --- > mm/cma.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/mm/cma.c b/mm/cma.c > index 7f415d7..07c904b 100644 > --- a/mm/cma.c > +++ b/mm/cma.c > @@ -512,7 +512,7 @@ bool cma_release(struct cma *cma, const struct page *pages, unsigned int count) > if (!cma || !pages) > return false; > > - pr_debug("%s(page %p)\n", __func__, (void *)pages); > + pr_debug("%s(page %p, count %zu)\n", __func__, (void *)pages, count); > > pfn = page_to_pfn(pages); > >
diff --git a/mm/cma.c b/mm/cma.c index 7f415d7..07c904b 100644 --- a/mm/cma.c +++ b/mm/cma.c @@ -512,7 +512,7 @@ bool cma_release(struct cma *cma, const struct page *pages, unsigned int count) if (!cma || !pages) return false; - pr_debug("%s(page %p)\n", __func__, (void *)pages); + pr_debug("%s(page %p, count %zu)\n", __func__, (void *)pages, count); pfn = page_to_pfn(pages);
It is required to print 'count' of pages, along with the pages, passed to cma_release to debug the cases of mismatched count value passed between cma_alloc() and cma_release() from a code path. As an example, consider the below scenario: 1) CMA pool size is 4MB and 2) User doing the erroneous step of allocating 2 pages but freeing 1 page in a loop from this CMA pool. The step 2 causes cma_alloc() to return NULL at one point of time because of -ENOMEM condition. And the current pr_debug logs is not giving the info about these types of allocation patterns because of count value not being printed in cma_release(). We are printing the count value in the trace logs, just extend the same to pr_debug logs too. Signed-off-by: Charan Teja Reddy <charante@codeaurora.org> --- mm/cma.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)