linux-kselftest.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Yury Norov <yury.norov@gmail.com>
To: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Yury Norov <yury.norov@gmail.com>,
	Andrew Morton <akpm@linux-foundation.org>,
	linux-kernel@vger.kernel.org, linux-mm@kvack.org,
	linux-arch@vger.kernel.org, linux-kselftest@vger.kernel.org,
	linux-mmc@vger.kernel.org, linux-perf-users@vger.kernel.org,
	kvm@vger.kernel.org,
	"James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>,
	Alexander Lobakin <alobakin@pm.me>,
	Alexander Shishkin <alexander.shishkin@linux.intel.com>,
	Alexey Klimov <aklimov@redhat.com>,
	Andrea Merello <andrea.merello@gmail.com>,
	Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
	Arnaldo Carvalho de Melo <acme@redhat.com>,
	Arnd Bergmann <arnd@arndb.de>, Ben Gardon <bgardon@google.com>,
	Benjamin Herrenschmidt <benh@kernel.crashing.org>,
	Brian Cain <bcain@codeaurora.org>,
	Catalin Marinas <catalin.marinas@arm.com>,
	Christoph Lameter <cl@linux.com>,
	Daniel Bristot de Oliveira <bristot@redhat.com>,
	David Hildenbrand <david@redhat.com>,
	Dennis Zhou <dennis@kernel.org>,
	Geert Uytterhoeven <geert@linux-m68k.org>,
	Heiko Carstens <hca@linux.ibm.com>,
	Ian Rogers <irogers@google.com>, Ingo Molnar <mingo@redhat.com>,
	Jaegeuk Kim <jaegeuk@kernel.org>,
	Jakub Kicinski <kuba@kernel.org>, Jiri Olsa <jolsa@redhat.com>,
	Joe Perches <joe@perches.com>, Jonas Bonn <jonas@southpole.se>,
	Leo Yan <leo.yan@linaro.org>, Mark Rutland <mark.rutland@arm.com>,
	Namhyung Kim <namhyung@kernel.org>,
	Palmer Dabbelt <palmer@dabbelt.com>,
	Paolo Bonzini <pbonzini@redhat.com>, Peter Xu <peterx@redhat.com>,
	Peter Zijlstra <peterz@infradead.org>,
	Petr Mladek <pmladek@suse.com>,
	Rasmus Villemoes <linux@rasmusvillemoes.dk>,
	Rich Felker <dalias@libc.org>,
	Samuel Mendoza-Jonas <sam@mendozajonas.com>,
	Sean Christopherson <seanjc@google.com>,
	Sergey Senozhatsky <senozhatsky@chromium.org>,
	Shuah Khan <shuah@kernel.org>,
	Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>,
	Steven Rostedt <rostedt@goodmis.org>, Tejun Heo <tj@kernel.org>,
	Thomas Bogendoerfer <tsbogend@alpha.franken.de>,
	Ulf Hansson <ulf.hansson@linaro.org>,
	Will Deacon <will@kernel.org>,
	Wolfram Sang <wsa+renesas@sang-engineering.com>,
	Yoshinori Sato <ysato@users.sourceforge.jp>
Subject: [PATCH 11/16] find: micro-optimize for_each_{set,clear}_bit()
Date: Fri,  1 Oct 2021 11:12:40 -0700	[thread overview]
Message-ID: <20211001181245.228419-12-yury.norov@gmail.com> (raw)
In-Reply-To: <20211001181245.228419-1-yury.norov@gmail.com>

The macros iterate thru all set/clear bits in a bitmap. They search a
first bit using find_first_bit(), and the rest bits using find_next_bit().

Since find_next_bit() is called shortly after find_first_bit(), we can
save few lines of I-cache by not using find_first_bit().

Signed-off-by: Yury Norov <yury.norov@gmail.com>
Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
---
 include/linux/find.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/include/linux/find.h b/include/linux/find.h
index 4500e8ab93e2..ae9ed52b52b8 100644
--- a/include/linux/find.h
+++ b/include/linux/find.h
@@ -280,7 +280,7 @@ unsigned long find_next_bit_le(const void *addr, unsigned
 #endif
 
 #define for_each_set_bit(bit, addr, size) \
-	for ((bit) = find_first_bit((addr), (size));		\
+	for ((bit) = find_next_bit((addr), (size), 0);		\
 	     (bit) < (size);					\
 	     (bit) = find_next_bit((addr), (size), (bit) + 1))
 
@@ -291,7 +291,7 @@ unsigned long find_next_bit_le(const void *addr, unsigned
 	     (bit) = find_next_bit((addr), (size), (bit) + 1))
 
 #define for_each_clear_bit(bit, addr, size) \
-	for ((bit) = find_first_zero_bit((addr), (size));	\
+	for ((bit) = find_next_zero_bit((addr), (size), 0);	\
 	     (bit) < (size);					\
 	     (bit) = find_next_zero_bit((addr), (size), (bit) + 1))
 
-- 
2.30.2


  parent reply	other threads:[~2021-10-01 18:14 UTC|newest]

Thread overview: 24+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-10-01 18:12 [PATCH RESEND 2 00/16] Resend bitmap patches Yury Norov
2021-10-01 18:12 ` [PATCH 01/16] bitops: protect find_first_{,zero}_bit properly Yury Norov
2021-10-01 18:12 ` [PATCH 02/16] bitops: move find_bit_*_le functions from le.h to find.h Yury Norov
2021-10-01 18:12 ` [PATCH 03/16] include: move find.h from asm_generic to linux Yury Norov
2021-10-02  9:23   ` Geert Uytterhoeven
2021-10-02 17:24     ` Yury Norov
2021-10-01 18:12 ` [PATCH 04/16] arch: remove GENERIC_FIND_FIRST_BIT entirely Yury Norov
2021-10-01 18:12 ` [PATCH 05/16] lib: add find_first_and_bit() Yury Norov
2021-10-01 18:12 ` [PATCH 06/16] cpumask: use find_first_and_bit() Yury Norov
2021-10-01 18:12 ` [PATCH 07/16] all: replace find_next{,_zero}_bit with find_first{,_zero}_bit where appropriate Yury Norov
2021-10-01 18:12 ` [PATCH 08/16] tools: sync tools/bitmap with mother linux Yury Norov
2021-10-01 18:12 ` [PATCH 09/16] cpumask: replace cpumask_next_* with cpumask_first_* where appropriate Yury Norov
2021-10-01 18:12 ` [PATCH 10/16] include/linux: move for_each_bit() macros from bitops.h to find.h Yury Norov
2021-10-01 18:12 ` Yury Norov [this message]
2021-10-01 18:12 ` [PATCH 12/16] Replace for_each_*_bit_from() with for_each_*_bit() where appropriate Yury Norov
2021-10-01 18:12 ` [PATCH 13/16] mm/percpu: micro-optimize pcpu_is_populated() Yury Norov
2021-10-01 18:12 ` [PATCH 14/16] bitmap: unify find_bit operations Yury Norov
2021-10-01 18:12 ` [PATCH 15/16] lib: bitmap: add performance test for bitmap_print_to_pagebuf Yury Norov
2021-10-01 18:12 ` [PATCH 16/16] vsprintf: rework bitmap_list_string Yury Norov
2021-10-02 22:47 ` [PATCH RESEND 2 00/16] Resend bitmap patches Stephen Rothwell
2021-10-02 23:10   ` Yury Norov
2021-10-02 23:41     ` Stephen Rothwell
2021-10-02 23:43     ` Stephen Rothwell
2021-10-05  5:40 [PATCH RESEND 3 00/16] Bitmap patches for 5.15 Yury Norov
2021-10-05  5:40 ` [PATCH 11/16] find: micro-optimize for_each_{set,clear}_bit() Yury Norov

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20211001181245.228419-12-yury.norov@gmail.com \
    --to=yury.norov@gmail.com \
    --cc=James.Bottomley@HansenPartnership.com \
    --cc=acme@redhat.com \
    --cc=aklimov@redhat.com \
    --cc=akpm@linux-foundation.org \
    --cc=alexander.shishkin@linux.intel.com \
    --cc=alobakin@pm.me \
    --cc=andrea.merello@gmail.com \
    --cc=andriy.shevchenko@linux.intel.com \
    --cc=arnd@arndb.de \
    --cc=bcain@codeaurora.org \
    --cc=benh@kernel.crashing.org \
    --cc=bgardon@google.com \
    --cc=bristot@redhat.com \
    --cc=catalin.marinas@arm.com \
    --cc=cl@linux.com \
    --cc=dalias@libc.org \
    --cc=david@redhat.com \
    --cc=dennis@kernel.org \
    --cc=geert@linux-m68k.org \
    --cc=hca@linux.ibm.com \
    --cc=irogers@google.com \
    --cc=jaegeuk@kernel.org \
    --cc=joe@perches.com \
    --cc=jolsa@redhat.com \
    --cc=jonas@southpole.se \
    --cc=kuba@kernel.org \
    --cc=kvm@vger.kernel.org \
    --cc=leo.yan@linaro.org \
    --cc=linux-arch@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-kselftest@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=linux-mmc@vger.kernel.org \
    --cc=linux-perf-users@vger.kernel.org \
    --cc=linux@rasmusvillemoes.dk \
    --cc=mark.rutland@arm.com \
    --cc=mingo@redhat.com \
    --cc=namhyung@kernel.org \
    --cc=palmer@dabbelt.com \
    --cc=pbonzini@redhat.com \
    --cc=peterx@redhat.com \
    --cc=peterz@infradead.org \
    --cc=pmladek@suse.com \
    --cc=rostedt@goodmis.org \
    --cc=sam@mendozajonas.com \
    --cc=seanjc@google.com \
    --cc=senozhatsky@chromium.org \
    --cc=sfr@canb.auug.org.au \
    --cc=shuah@kernel.org \
    --cc=stefan.kristiansson@saunalahti.fi \
    --cc=tj@kernel.org \
    --cc=tsbogend@alpha.franken.de \
    --cc=ulf.hansson@linaro.org \
    --cc=will@kernel.org \
    --cc=wsa+renesas@sang-engineering.com \
    --cc=ysato@users.sourceforge.jp \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).