[PATCH v2 06/19 5.15.y] minmax: add a few more MIN_T/MAX_T users
From: Eliav Farber <hidden>
Date: 2025-10-03 13:03:32
Also in:
amd-gfx, dri-devel, linux-arm-msm, linux-btrfs, linux-edac, linux-ext4, linux-hwmon, linux-input, linux-kselftest, linux-media, linux-mm, linux-scsi, linux-staging, linux-sunxi, linux-um, lkml, netfilter-devel, platform-driver-x86, stable
Subsystem:
device-mapper (lvm), drm drivers, drm drivers and misc gpu patches, edac-core, edac-sbridge, networking drivers, networking [general], stmmac ethernet driver, the rest, x86 architecture (32-bit and 64-bit), x86 mm · Maintainers:
Alasdair Kergon, Mike Snitzer, Mikulas Patocka, Benjamin Marzinski, David Airlie, Simona Vetter, Maarten Lankhorst, Maxime Ripard, Thomas Zimmermann, Borislav Petkov, Tony Luck, Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds, Thomas Gleixner, Ingo Molnar, Dave Hansen, Andy Lutomirski, Peter Zijlstra
From: Linus Torvalds <torvalds@linux-foundation.org>
[ Upstream commit 4477b39c32fdc03363affef4b11d48391e6dc9ff ]
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/ (local)
Cc: David Laight <redacted>
Cc: Lorenzo Stoakes <redacted>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Eliav Farber <redacted>
---
V1 -> V2:
Use `[ Upstream commit <HASH> ]` instead of `commit <HASH> upstream.`
like in all other patches.
arch/x86/mm/pgtable.c | 2 +-
drivers/edac/sb_edac.c | 4 ++--
drivers/gpu/drm/drm_color_mgmt.c | 2 +-
drivers/md/dm-integrity.c | 2 +-
drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 2 +-
net/ipv4/proc.c | 2 +-
net/ipv6/proc.c | 2 +-
7 files changed, 8 insertions(+), 8 deletions(-)
diff --git a/arch/x86/mm/pgtable.c b/arch/x86/mm/pgtable.c
index 3481b35cb4ec..e649161eb6fc 100644
--- a/arch/x86/mm/pgtable.c
+++ b/arch/x86/mm/pgtable.c@@ -107,7 +107,7 @@ 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)
diff --git a/drivers/edac/sb_edac.c b/drivers/edac/sb_edac.c
index 1522d4aa2ca6..714020e7405a 100644
--- a/drivers/edac/sb_edac.c
+++ b/drivers/edac/sb_edac.c@@ -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 {
diff --git a/drivers/gpu/drm/drm_color_mgmt.c b/drivers/gpu/drm/drm_color_mgmt.c
index bb14f488c8f6..1ff572d8744e 100644
--- a/drivers/gpu/drm/drm_color_mgmt.c
+++ b/drivers/gpu/drm/drm_color_mgmt.c@@ -528,7 +528,7 @@ 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;
diff --git a/drivers/md/dm-integrity.c b/drivers/md/dm-integrity.c
index e9d553eea9cd..8e2b00536c3e 100644
--- a/drivers/md/dm-integrity.c
+++ b/drivers/md/dm-integrity.c@@ -2536,7 +2536,7 @@ static void do_journal_write(struct dm_integrity_c *ic, unsigned 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);
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index 2478caeec763..21cc8cd9e023 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c@@ -2805,7 +2805,7 @@ 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)))
diff --git a/net/ipv4/proc.c b/net/ipv4/proc.c
index 4b9280a3b673..d849f61b7519 100644
--- a/net/ipv4/proc.c
+++ b/net/ipv4/proc.c@@ -43,7 +43,7 @@ #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]
diff --git a/net/ipv6/proc.c b/net/ipv6/proc.c
index d6306aa46bb1..e07c43bd5cb0 100644
--- a/net/ipv6/proc.c
+++ b/net/ipv6/proc.c@@ -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)
--
2.47.3