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minmax: add a few more MIN_T/MAX_T users

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Commit 3a7e02c040 ("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>
This commit is contained in:
Linus Torvalds 2024-07-28 13:03:48 -07:00
parent 7e2d0ba732
commit 4477b39c32
7 changed files with 10 additions and 10 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
arch/x86/mm/pgtable.c
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@ -110,7 +110,7 @@ static inline void pgd_list_del(pgd_t *pgd)
#define UNSHARED_PTRS_PER_PGD \
(SHARED_KERNEL_PMD ? KERNEL_PGD_BOUNDARY : PTRS_PER_PGD)
#define MAX_UNSHARED_PTRS_PER_PGD \
max_t(size_t, KERNEL_PGD_BOUNDARY, PTRS_PER_PGD)
MAX_T(size_t, KERNEL_PGD_BOUNDARY, PTRS_PER_PGD)
static void pgd_set_mm(pgd_t *pgd, struct mm_struct *mm)

4
drivers/edac/sb_edac.c
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@ -109,8 +109,8 @@ static const u32 knl_interleave_list[] = {
0x104, 0x10c, 0x114, 0x11c, /* 20-23 */
};
#define MAX_INTERLEAVE \
(max_t(unsigned int, ARRAY_SIZE(sbridge_interleave_list), \
max_t(unsigned int, ARRAY_SIZE(ibridge_interleave_list), \
(MAX_T(unsigned int, ARRAY_SIZE(sbridge_interleave_list), \
MAX_T(unsigned int, ARRAY_SIZE(ibridge_interleave_list), \
ARRAY_SIZE(knl_interleave_list))))
struct interleave_pkg {

2
drivers/gpu/drm/drm_color_mgmt.c
View File

@ -532,7 +532,7 @@ int drm_plane_create_color_properties(struct drm_plane *plane,
{
struct drm_device *dev = plane->dev;
struct drm_property *prop;
struct drm_prop_enum_list enum_list[max_t(int, DRM_COLOR_ENCODING_MAX,
struct drm_prop_enum_list enum_list[MAX_T(int, DRM_COLOR_ENCODING_MAX,
DRM_COLOR_RANGE_MAX)];
int i, len;

6
drivers/md/dm-integrity.c
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@ -1776,7 +1776,7 @@ static void integrity_metadata(struct work_struct *w)
struct bio *bio = dm_bio_from_per_bio_data(dio, sizeof(struct dm_integrity_io));
char *checksums;
unsigned int extra_space = unlikely(digest_size > ic->tag_size) ? digest_size - ic->tag_size : 0;
char checksums_onstack[max_t(size_t, HASH_MAX_DIGESTSIZE, MAX_TAG_SIZE)];
char checksums_onstack[MAX_T(size_t, HASH_MAX_DIGESTSIZE, MAX_TAG_SIZE)];
sector_t sector;
unsigned int sectors_to_process;
@ -2064,7 +2064,7 @@ static bool __journal_read_write(struct dm_integrity_io *dio, struct bio *bio,
} while (++s < ic->sectors_per_block);
#ifdef INTERNAL_VERIFY
if (ic->internal_hash) {
char checksums_onstack[max_t(size_t, HASH_MAX_DIGESTSIZE, MAX_TAG_SIZE)];
char checksums_onstack[MAX_T(size_t, HASH_MAX_DIGESTSIZE, MAX_TAG_SIZE)];
integrity_sector_checksum(ic, logical_sector, mem + bv.bv_offset, checksums_onstack);
if (unlikely(memcmp(checksums_onstack, journal_entry_tag(ic, je), ic->tag_size))) {
@ -2837,7 +2837,7 @@ static void do_journal_write(struct dm_integrity_c *ic, unsigned int write_start
unlikely(from_replay) &&
#endif
ic->internal_hash) {
char test_tag[max_t(size_t, HASH_MAX_DIGESTSIZE, MAX_TAG_SIZE)];
char test_tag[MAX_T(size_t, HASH_MAX_DIGESTSIZE, MAX_TAG_SIZE)];
integrity_sector_checksum(ic, sec + ((l - j) << ic->sb->log2_sectors_per_block),
(char *)access_journal_data(ic, i, l), test_tag);

2
drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
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@ -2912,7 +2912,7 @@ static void stmmac_dma_interrupt(struct stmmac_priv *priv)
u32 channels_to_check = tx_channel_count > rx_channel_count ?
tx_channel_count : rx_channel_count;
u32 chan;
int status[max_t(u32, MTL_MAX_TX_QUEUES, MTL_MAX_RX_QUEUES)];
int status[MAX_T(u32, MTL_MAX_TX_QUEUES, MTL_MAX_RX_QUEUES)];
/* Make sure we never check beyond our status buffer. */
if (WARN_ON_ONCE(channels_to_check > ARRAY_SIZE(status)))

2
net/ipv4/proc.c
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@ -44,7 +44,7 @@
#include <net/sock.h>
#include <net/raw.h>
#define TCPUDP_MIB_MAX max_t(u32, UDP_MIB_MAX, TCP_MIB_MAX)
#define TCPUDP_MIB_MAX MAX_T(u32, UDP_MIB_MAX, TCP_MIB_MAX)
/*
* Report socket allocation statistics [mea@utu.fi]

2
net/ipv6/proc.c
View File

@ -27,7 +27,7 @@
#include <net/ipv6.h>
#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)