tjh.dev / kernel
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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 <David.Laight@aculab.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Linus Torvalds 4477b39c 7e2d0ba7

+10 -10
+1 -1
arch/x86/mm/pgtable.c
··· 110 110 #define UNSHARED_PTRS_PER_PGD \ 111 111 (SHARED_KERNEL_PMD ? KERNEL_PGD_BOUNDARY : PTRS_PER_PGD) 112 112 #define MAX_UNSHARED_PTRS_PER_PGD \ 113 - max_t(size_t, KERNEL_PGD_BOUNDARY, PTRS_PER_PGD) 113 + MAX_T(size_t, KERNEL_PGD_BOUNDARY, PTRS_PER_PGD) 114 114 115 115 116 116 static void pgd_set_mm(pgd_t *pgd, struct mm_struct *mm)
+2 -2
drivers/edac/sb_edac.c
··· 109 109 0x104, 0x10c, 0x114, 0x11c, /* 20-23 */ 110 110 }; 111 111 #define MAX_INTERLEAVE \ 112 - (max_t(unsigned int, ARRAY_SIZE(sbridge_interleave_list), \ 113 - max_t(unsigned int, ARRAY_SIZE(ibridge_interleave_list), \ 112 + (MAX_T(unsigned int, ARRAY_SIZE(sbridge_interleave_list), \ 113 + MAX_T(unsigned int, ARRAY_SIZE(ibridge_interleave_list), \ 114 114 ARRAY_SIZE(knl_interleave_list)))) 115 115 116 116 struct interleave_pkg {
+1 -1
drivers/gpu/drm/drm_color_mgmt.c
··· 532 532 { 533 533 struct drm_device *dev = plane->dev; 534 534 struct drm_property *prop; 535 - struct drm_prop_enum_list enum_list[max_t(int, DRM_COLOR_ENCODING_MAX, 535 + struct drm_prop_enum_list enum_list[MAX_T(int, DRM_COLOR_ENCODING_MAX, 536 536 DRM_COLOR_RANGE_MAX)]; 537 537 int i, len; 538 538
+3 -3
drivers/md/dm-integrity.c
··· 1776 1776 struct bio *bio = dm_bio_from_per_bio_data(dio, sizeof(struct dm_integrity_io)); 1777 1777 char *checksums; 1778 1778 unsigned int extra_space = unlikely(digest_size > ic->tag_size) ? digest_size - ic->tag_size : 0; 1779 - char checksums_onstack[max_t(size_t, HASH_MAX_DIGESTSIZE, MAX_TAG_SIZE)]; 1779 + char checksums_onstack[MAX_T(size_t, HASH_MAX_DIGESTSIZE, MAX_TAG_SIZE)]; 1780 1780 sector_t sector; 1781 1781 unsigned int sectors_to_process; 1782 1782 ··· 2064 2064 } while (++s < ic->sectors_per_block); 2065 2065 #ifdef INTERNAL_VERIFY 2066 2066 if (ic->internal_hash) { 2067 - char checksums_onstack[max_t(size_t, HASH_MAX_DIGESTSIZE, MAX_TAG_SIZE)]; 2067 + char checksums_onstack[MAX_T(size_t, HASH_MAX_DIGESTSIZE, MAX_TAG_SIZE)]; 2068 2068 2069 2069 integrity_sector_checksum(ic, logical_sector, mem + bv.bv_offset, checksums_onstack); 2070 2070 if (unlikely(memcmp(checksums_onstack, journal_entry_tag(ic, je), ic->tag_size))) { ··· 2837 2837 unlikely(from_replay) && 2838 2838 #endif 2839 2839 ic->internal_hash) { 2840 - char test_tag[max_t(size_t, HASH_MAX_DIGESTSIZE, MAX_TAG_SIZE)]; 2840 + char test_tag[MAX_T(size_t, HASH_MAX_DIGESTSIZE, MAX_TAG_SIZE)]; 2841 2841 2842 2842 integrity_sector_checksum(ic, sec + ((l - j) << ic->sb->log2_sectors_per_block), 2843 2843 (char *)access_journal_data(ic, i, l), test_tag);
+1 -1
drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
··· 2912 2912 u32 channels_to_check = tx_channel_count > rx_channel_count ? 2913 2913 tx_channel_count : rx_channel_count; 2914 2914 u32 chan; 2915 - int status[max_t(u32, MTL_MAX_TX_QUEUES, MTL_MAX_RX_QUEUES)]; 2915 + int status[MAX_T(u32, MTL_MAX_TX_QUEUES, MTL_MAX_RX_QUEUES)]; 2916 2916 2917 2917 /* Make sure we never check beyond our status buffer. */ 2918 2918 if (WARN_ON_ONCE(channels_to_check > ARRAY_SIZE(status)))
+1 -1
net/ipv4/proc.c
··· 44 44 #include <net/sock.h> 45 45 #include <net/raw.h> 46 46 47 - #define TCPUDP_MIB_MAX max_t(u32, UDP_MIB_MAX, TCP_MIB_MAX) 47 + #define TCPUDP_MIB_MAX MAX_T(u32, UDP_MIB_MAX, TCP_MIB_MAX) 48 48 49 49 /* 50 50 * Report socket allocation statistics [mea@utu.fi]
+1 -1
net/ipv6/proc.c
··· 27 27 #include <net/ipv6.h> 28 28 29 29 #define MAX4(a, b, c, d) \ 30 - max_t(u32, max_t(u32, a, b), max_t(u32, c, d)) 30 + MAX_T(u32, MAX_T(u32, a, b), MAX_T(u32, c, d)) 31 31 #define SNMP_MIB_MAX MAX4(UDP_MIB_MAX, TCP_MIB_MAX, \ 32 32 IPSTATS_MIB_MAX, ICMP_MIB_MAX) 33 33