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* [merged] lib-uninline-simple_strtoull.patch removed from -mm tree
@ 2021-07-06 19:22 akpm
  0 siblings, 0 replies; only message in thread
From: akpm @ 2021-07-06 19:22 UTC (permalink / raw)
  To: adobriyan, mm-commits


The patch titled
     Subject: lib: uninline simple_strtoull()
has been removed from the -mm tree.  Its filename was
     lib-uninline-simple_strtoull.patch

This patch was dropped because it was merged into mainline or a subsystem tree

------------------------------------------------------
From: Alexey Dobriyan <adobriyan@gmail.com>
Subject: lib: uninline simple_strtoull()

Gcc inlines simple_strtoull() too agressively.

Given that all 4 signatures match, everything very efficiently calls or
tailcalls into simple_strtoull():

	ffffffff81da0240 <simple_strtoll>:
	ffffffff81da0240:       80 3f 2d                cmp    BYTE PTR [rdi],0x2d
	ffffffff81da0243:       74 05                   je     ffffffff81da024a <simple_strtoll+0xa>
	ffffffff81da0245:       e9 76 ff ff ff          jmp    simple_strtoull
	ffffffff81da024a:       48 83 c7 01             add    rdi,0x1
	ffffffff81da024e:       e8 6d ff ff ff          call   simple_strtoull
	ffffffff81da0253:       48 f7 d8                neg    rax
	ffffffff81da0256:       c3                      ret

Space savings (on F34-ish .config)

	add/remove: 0/0 grow/shrink: 1/3 up/down: 52/-313 (-261)
	Function                                     old     new   delta
	vsscanf                                     2167    2219     +52
	simple_strtoul                                72       2     -70
	simple_strtoll                               143      23    -120
	simple_strtol                                143      20    -123

Link: https://lkml.kernel.org/r/YMO2zoOQk2eF34tn@localhost.localdomain
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 lib/vsprintf.c |    1 +
 1 file changed, 1 insertion(+)

--- a/lib/vsprintf.c~lib-uninline-simple_strtoull
+++ a/lib/vsprintf.c
@@ -61,6 +61,7 @@
  *
  * This function has caveats. Please use kstrtoull instead.
  */
+noinline
 unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base)
 {
 	unsigned long long result;
_

Patches currently in -mm which might be from adobriyan@gmail.com are



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2021-07-06 19:22 [merged] lib-uninline-simple_strtoull.patch removed from -mm tree akpm

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