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a383308e50
list_for_each_entry_safe is able to handle an empty list. The only effect of avoiding the loop is not initializing the index variable. Drop list_empty tests in cases where these variables are not used. Note that list_for_each_entry_safe is defined in terms of list_first_entry, which indicates that it should not be used on an empty list. But in list_for_each_entry_safe, the element obtained by list_first_entry is not really accessed, only the address of its list_head field is compared to the address of the list head, so the list_first_entry is safe. The semantic patch that makes this change is as follows (with another variant for the no brace case): (http://coccinelle.lip6.fr/) <smpl> @@ expression x,e; iterator name list_for_each_entry_safe; statement S; identifier i,j; @@ -if (!(list_empty(x))) { list_for_each_entry_safe(i,j,x,...) S - } ... when != i when != j ( i = e; | ? j = e; ) </smpl> Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr> Link: https://lore.kernel.org/r/1595761112-11003-2-git-send-email-Julia.Lawall@inria.fr Signed-off-by: Mark Brown <broonie@kernel.org>