minmax: add in_range() macro

Patch series "New page table range API", v6.

This patchset changes the API used by the MM to set up page table entries.
The four APIs are:

    set_ptes(mm, addr, ptep, pte, nr)
    update_mmu_cache_range(vma, addr, ptep, nr)
    flush_dcache_folio(folio) 
    flush_icache_pages(vma, page, nr)

flush_dcache_folio() isn't technically new, but no architecture
implemented it, so I've done that for them.  The old APIs remain around
but are mostly implemented by calling the new interfaces.

The new APIs are based around setting up N page table entries at once. 
The N entries belong to the same PMD, the same folio and the same VMA, so
ptep++ is a legitimate operation, and locking is taken care of for you. 
Some architectures can do a better job of it than just a loop, but I have
hesitated to make too deep a change to architectures I don't understand
well.

One thing I have changed in every architecture is that PG_arch_1 is now a
per-folio bit instead of a per-page bit when used for dcache clean/dirty
tracking.  This was something that would have to happen eventually, and it
makes sense to do it now rather than iterate over every page involved in a
cache flush and figure out if it needs to happen.

The point of all this is better performance, and Fengwei Yin has measured
improvement on x86.  I suspect you'll see improvement on your architecture
too.  Try the new will-it-scale test mentioned here:
https://lore.kernel.org/linux-mm/20230206140639.538867-5-fengwei.yin@intel.com/
You'll need to run it on an XFS filesystem and have
CONFIG_TRANSPARENT_HUGEPAGE set.

This patchset is the basis for much of the anonymous large folio work
being done by Ryan, so it's received quite a lot of testing over the last
few months.


This patch (of 38):

Determine if a value lies within a range more efficiently (subtraction +
comparison vs two comparisons and an AND).  It also has useful (under some
circumstances) behaviour if the range exceeds the maximum value of the
type.  Convert all the conflicting definitions of in_range() within the
kernel; some can use the generic definition while others need their own
definition.

Link: https://lkml.kernel.org/r/20230802151406.3735276-1-willy@infradead.org
Link: https://lkml.kernel.org/r/20230802151406.3735276-2-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

2 files changed, 6 insertions, 6 deletions

diff --git a/net/tipc/core.h b/net/tipc/core.h
index 0a3f7a70a50a..7eccd97e0609 100644
--- a/net/tipc/core.h
+++ b/net/tipc/core.h
@@ -197,7 +197,7 @@ static inline int less(u16 left, u16 right)
 	return less_eq(left, right) && (mod(right) != mod(left));
 }
 
-static inline int in_range(u16 val, u16 min, u16 max)
+static inline int tipc_in_range(u16 val, u16 min, u16 max)
 {
 	return !less(val, min) && !more(val, max);
 }
diff --git a/net/tipc/link.c b/net/tipc/link.c
index 2eff1c7949cb..e33b4f29f77c 100644
--- a/net/tipc/link.c
+++ b/net/tipc/link.c
@@ -1623,7 +1623,7 @@ next_gap_ack:
 					  last_ga->bgack_cnt);
 			}
 			/* Check against the last Gap ACK block */
-			if (in_range(seqno, start, end))
+			if (tipc_in_range(seqno, start, end))
 				continue;
 			/* Update/release the packet peer is acking */
 			bc_has_acked = true;
@@ -2251,12 +2251,12 @@ static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb,
 		strncpy(if_name, data, TIPC_MAX_IF_NAME);
 
 		/* Update own tolerance if peer indicates a non-zero value */
-		if (in_range(peers_tol, TIPC_MIN_LINK_TOL, TIPC_MAX_LINK_TOL)) {
+		if (tipc_in_range(peers_tol, TIPC_MIN_LINK_TOL, TIPC_MAX_LINK_TOL)) {
 			l->tolerance = peers_tol;
 			l->bc_rcvlink->tolerance = peers_tol;
 		}
 		/* Update own priority if peer's priority is higher */
-		if (in_range(peers_prio, l->priority + 1, TIPC_MAX_LINK_PRI))
+		if (tipc_in_range(peers_prio, l->priority + 1, TIPC_MAX_LINK_PRI))
 			l->priority = peers_prio;
 
 		/* If peer is going down we want full re-establish cycle */
@@ -2299,13 +2299,13 @@ static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb,
 		l->rcv_nxt_state = msg_seqno(hdr) + 1;
 
 		/* Update own tolerance if peer indicates a non-zero value */
-		if (in_range(peers_tol, TIPC_MIN_LINK_TOL, TIPC_MAX_LINK_TOL)) {
+		if (tipc_in_range(peers_tol, TIPC_MIN_LINK_TOL, TIPC_MAX_LINK_TOL)) {
 			l->tolerance = peers_tol;
 			l->bc_rcvlink->tolerance = peers_tol;
 		}
 		/* Update own prio if peer indicates a different value */
 		if ((peers_prio != l->priority) &&
-		    in_range(peers_prio, 1, TIPC_MAX_LINK_PRI)) {
+		    tipc_in_range(peers_prio, 1, TIPC_MAX_LINK_PRI)) {
 			l->priority = peers_prio;
 			rc = tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
 		}