device-dax: Avoid an unnecessary check in alloc_dev_dax_range() (ff8da37d) · Commits · 戴 / test

Swap the calling sequence of krealloc() and __request_region(), call the latter first. In this way, the value of dev_dax->nr_range does not need to be considered when __request_region() failed. Signed-off-by:

Zhen Lei <thunder.leizhen@huawei.com> Link: https://lore.kernel.org/r/20201219081840.1149-2-thunder.leizhen@huawei.com Signed-off-by:

Dan Williams <dan.j.williams@intel.com>

drivers/dax/bus.c

+6 −14

Original line number	Diff line number	Diff line
		@@ -772,22 +772,14 @@ static int alloc_dev_dax_range(struct dev_dax *dev_dax, u64 start,
		return 0;
		}

		ranges = krealloc(dev_dax->ranges, sizeof(*ranges)
		* (dev_dax->nr_range + 1), GFP_KERNEL);
		if (!ranges)
		alloc = __request_region(res, start, size, dev_name(dev), 0);
		if (!alloc)
		return -ENOMEM;

		alloc = __request_region(res, start, size, dev_name(dev), 0);
		if (!alloc) {
		/*
		* If this was an empty set of ranges nothing else
		* will release @ranges, so do it now.
		*/
		if (!dev_dax->nr_range) {
		kfree(ranges);
		ranges = NULL;
		}
		dev_dax->ranges = ranges;
		ranges = krealloc(dev_dax->ranges, sizeof(*ranges)
		* (dev_dax->nr_range + 1), GFP_KERNEL);
		if (!ranges) {
		__release_region(res, alloc->start, resource_size(alloc));
		return -ENOMEM;
		}

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