Commit 4477b39c authored by Linus Torvalds's avatar Linus Torvalds
Browse files

minmax: add a few more MIN_T/MAX_T users 

Commit 3a7e02c0 ("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: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 7e2d0ba7

arch/x86/mm/pgtable.c

+1 −1
Original line number Diff line number Diff line
@@ -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)

drivers/edac/sb_edac.c

+2 −2
Original line number Diff line number Diff line
@@ -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 {

drivers/gpu/drm/drm_color_mgmt.c

+1 −1
Original line number Diff line number Diff line
@@ -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;

drivers/md/dm-integrity.c

+3 −3
Original line number Diff line number Diff line
@@ -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);

drivers/net/ethernet/stmicro/stmmac/stmmac_main.c

+1 −1
Original line number Diff line number Diff line
@@ -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)))