From 4477b39c32fdc03363affef4b11d48391e6dc9ff Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sun, 28 Jul 2024 13:03:48 -0700 Subject: minmax: add a few more MIN_T/MAX_T users Commit 3a7e02c040b1 ("minmax: avoid overly complicated constant expressions in VM code") added the simpler MIN_T/MAX_T macros in order to avoid some excessive expansion from the rather complicated regular min/max macros. The complexity of those macros stems from two issues: (a) trying to use them in situations that require a C constant expression (in static initializers and for array sizes) (b) the type sanity checking and MIN_T/MAX_T avoids both of these issues. Now, in the whole (long) discussion about all this, it was pointed out that the whole type sanity checking is entirely unnecessary for min_t/max_t which get a fixed type that the comparison is done in. But that still leaves min_t/max_t unnecessarily complicated due to worries about the C constant expression case. However, it turns out that there really aren't very many cases that use min_t/max_t for this, and we can just force-convert those. This does exactly that. Which in turn will then allow for much simpler implementations of min_t()/max_t(). All the usual "macros in all upper case will evaluate the arguments multiple times" rules apply. We should do all the same things for the regular min/max() vs MIN/MAX() cases, but that has the added complexity of various drivers defining their own local versions of MIN/MAX, so that needs another level of fixes first. Link: https://lore.kernel.org/all/b47fad1d0cf8449886ad148f8c013dae@AcuMS.aculab.com/ Cc: David Laight Cc: Lorenzo Stoakes Signed-off-by: Linus Torvalds --- net/ipv6/proc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net/ipv6') diff --git a/net/ipv6/proc.c b/net/ipv6/proc.c index 6d1d9221649d..752327b10dde 100644 --- a/net/ipv6/proc.c +++ b/net/ipv6/proc.c @@ -27,7 +27,7 @@ #include #define MAX4(a, b, c, d) \ - max_t(u32, max_t(u32, a, b), max_t(u32, c, d)) + MAX_T(u32, MAX_T(u32, a, b), MAX_T(u32, c, d)) #define SNMP_MIB_MAX MAX4(UDP_MIB_MAX, TCP_MIB_MAX, \ IPSTATS_MIB_MAX, ICMP_MIB_MAX) -- cgit