flush_dcache_page() is only a few lines, it is worth
inlining.
ia64, csky, mips, openrisc and riscv have a similar
flush_dcache_page() and inline it.
On pmac32_defconfig, we get a small size reduction.
On ppc64_defconfig, we get a very small size increase.
In both case that's in the noise (less than 0.1%).
text data bss dec hex filename
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18994829 59367321497624 26429185 1934701 vmlinux64.after
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Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/21c417488b70b7629dae316539fb7bb8bdef4fdd.1617895813.git.christophe.leroy@csgroup.eu
__flush_dcache_icache() is usable for non HIGHMEM pages on
every platform.
It is only for HIGHMEM pages that BOOKE needs kmap() and
BOOK3S needs flush_dcache_icache_phys().
So make flush_dcache_icache_phys() dependent on CONFIG_HIGHMEM and
call it only when it is a HIGHMEM page.
We could make flush_dcache_icache_phys() available at all time,
but as it is declared NOKPROBE_SYMBOL(), GCC doesn't optimise
it out when it is not used.
So define a stub for !CONFIG_HIGHMEM in order to remove the #ifdef in
flush_dcache_icache_page() and use IS_ENABLED() instead.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/79ed5d7914f497cd5fcd681ca2f4d50a91719455.1617895813.git.christophe.leroy@csgroup.eu
flush_dcache_icache_hugepage() is a static function, with
only one caller. That caller calls it when PageCompound() is true,
so bugging on !PageCompound() is useless if we can trust the
compiler a little. Remove the BUG_ON(!PageCompound()).
The number of elements of a page won't change over time, but
GCC doesn't know about it, so it gets the value at every iteration.
To avoid that, call compound_nr() outside the loop and save it in
a local variable.
Whether the page is a HIGHMEM page or not doesn't change over time.
But GCC doesn't know it so it does the test on every iteration.
Do the test outside the loop.
When the page is not a HIGHMEM page, page_address() will fallback on
lowmem_page_address(), so call lowmem_page_address() directly and
don't suffer the call to page_address() on every iteration.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/ab03712b70105fccfceef095aa03007de9295a40.1617895813.git.christophe.leroy@csgroup.eu
flush_coherent_icache() doesn't need the address anymore,
so it can be called immediately when entering the public
functions and doesn't need to be disseminated among
lower level functions.
And use page_to_phys() instead of open coding the calculation
of phys address to call flush_dcache_icache_phys().
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/5f063986e325d2efdd404b8f8c5f4bcbd4eb11a6.1617895813.git.christophe.leroy@csgroup.eu
