When we're searching for toplevel devpts mount into which
the toplevel /dev/ptmx device is pointing to we should use
mnt_id from mountinfo first, this is most reliable way to
detect mounting.
But on old kernels mnt_id may not be present so we should
try s_dev lookup then and here is a nit --
tcache_shrink_scan() tcache_destroy_pool
tcache_lru_isolate()
tcache_grab_pool()
...
page_cache_get_speculative() -->cnt == 2
...
tcache_put_pool() --> pool cnt zero
...
When there are more than 2 users of a page, __tcache_page_tree_delete()
fails to freeze it. We skip it and never try to freeze the page again.
In this case the page remains not invalidated, and tcache_node->nr_pages
never decremented. Later, we catch WARN_ON() reporting about this.
The patch
On 30.11.2017 16:43, Andrey Ryabinin wrote:
> Tcache code filled with BUG_ON() checks. However the most cases
> issues that BUG_ON() supposed to catch are not serious enough
> to kill machine. So relax it's to WARN_ON.
> Remove BUG_ON() in tcache_init_fs(), because it's useless.
> It's called from
Tcache code filled with BUG_ON() checks. However the most cases
issues that BUG_ON() supposed to catch are not serious enough
to kill machine. So relax it's to WARN_ON.
Remove BUG_ON() in tcache_init_fs(), because it's useless.
It's called from the only one place in the kernel, which looks
like
On 11/30/2017 04:24 PM, Kirill Tkhai wrote:
> On 30.11.2017 15:06, Andrey Ryabinin wrote:
>> Tcache code filled with BUG_ON() checks. However the most cases
>> issues that BUG_ON() supposed to catch are not serious enough
>> to kill machine. So relax it's to WARN_ON.
>> Remove BUG_ON() in
On 30.11.2017 15:06, Andrey Ryabinin wrote:
> Tcache code filled with BUG_ON() checks. However the most cases
> issues that BUG_ON() supposed to catch are not serious enough
> to kill machine. So relax it's to WARN_ON.
> Remove BUG_ON() in tcache_init_fs(), because it's useless.
> It's called from
Tcache code filled with BUG_ON() checks. However the most cases
issues that BUG_ON() supposed to catch are not serious enough
to kill machine. So relax it's to WARN_ON.
Remove BUG_ON() in tcache_init_fs(), because it's useless.
It's called from the only one place in the kernel, which looks
like
