Re: [RFC PATCH v1 15/17] blk-cgroup: remove blkg radix tree preloading
Christoph Hellwig <[email protected]>
| Newsgroups | org.infradead.lists.linux-nvme,dev.linux.lists.dm-devel,org.kernel.vger.cgroups,org.kernel.vger.linux-bcache,org.kernel.vger.linux-block |
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| Message-ID | <[email protected]> |
On Sun, Jul 05, 2026 at 03:51:22AM +0800, Yu Kuai wrote: > From: Yu Kuai <[email protected]> > > blkg creation is now serialized by q->blkcg_mutex and no longer runs > under q->queue_lock. The radix tree is initialized with GFP_NOWAIT, so > radix_tree_insert() cannot sleep while blkcg->lock is held and the old > preload dance is no longer needed. > > Remove the preload calls and the associated unwind path. Isn't the GFP_NOWAIT a bit of a problem because it can fail way too easy? What about converting both the radix tree and list to an xarray using the internal xarray to deal with sleeping allocations?