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([94.75.70.14]) by smtp.gmail.com with ESMTPSA id p2-20020a056512328200b00516cd83e497sm1893187lfe.210.2024.04.17.03.05.06 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 17 Apr 2024 03:05:07 -0700 (PDT) X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" X-Inumbo-ID: 0a7aec8d-fca2-11ee-b909-491648fe20b8 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1713348338; x=1713953138; darn=lists.xenproject.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=Q5ULn7J+C23bytnZegqIYlqxigksIJAvnkht5gx5amU=; b=Yq0hfKRGbxWLDAj2fnlMRlhxR/jHNx/a/J70Q8AVIl2z0sSaHAGQ+C6Zg/XSKl6Gs+ Np0EnjaQDqoUmF4PFRK7BxVanwMZk36zaIHm3m92rdI4AvfbCM5JX7q0sl4UnpiCzOXT 7+apaDe9vBJ3P0mmVD1qCu67f+LNEGmBzejAT01k4u9PqsAAFcUAC4zsYUVXfsh6sRqm Lw0zQ/KqyK3kAB9CCjNFW4/6xIn3P/kSA1RCIF9cWlkK5Ym/7SPnOuyLvepTn8qTB1OF DKL35aS9Vq90hnMYwCp08J/rgBJL7l/4vBoa1XUp9hp6/KYxYxisi8QF+s4yv3XbE7uN Z5ag== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1713348338; x=1713953138; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=Q5ULn7J+C23bytnZegqIYlqxigksIJAvnkht5gx5amU=; b=mETPqGu+18VrUod1b8Fx6GrDEvncZgnX3Z1wv8Tm/YKi2Gkr08bI2A+uoPcEVaDpfg J0jHgLxjjnCO6yREgdTZi3fRyrKTNYQ2Yup2vRcRubxrOHmHJw41Pvml93d2xAuh/Izt N2Wc9GBg5mLX5/jgwFWE/G0oddGntRXY17mCq+19tvhrWsHDTwow9+g8oYJPvZnsOudM HeA6idIMwVWE29auCCE7JnpPxkYQfea1KcIcilBoFgiVyWX7TVgyFfADvRcLEZdyUdIQ DYGToFsLt9JC3m29DOqxEMqCK+G9zBsC5IWja58no/EvMKSyUSrJr3sJH5rRau6rpXqa Z2BA== X-Gm-Message-State: AOJu0YxaOBuhzTlv926910wFIBMa6fa3iO/06vJv88QNLQO6XgrtOTZC POmwqfinFFESiiBettbrqDv8zQSIeE1KhS+yjzc4y9xiJE+/MNp5x/TK0A== X-Google-Smtp-Source: AGHT+IFuNF9ms6azISaKCHmPIxauFJJF0/Y3ZA1fsWpaRswYHa+kDy29+3l8sQU3UTWlpJPMmPrhZA== X-Received: by 2002:ac2:4182:0:b0:516:d0c2:755 with SMTP id z2-20020ac24182000000b00516d0c20755mr8877498lfh.63.1713348308113; Wed, 17 Apr 2024 03:05:08 -0700 (PDT) From: Oleksii Kurochko To: xen-devel@lists.xenproject.org Cc: Oleksii Kurochko , Stefano Stabellini , Julien Grall , Bertrand Marquis , Michal Orzel , Volodymyr Babchuk , Andrew Cooper , George Dunlap , Jan Beulich , Shawn Anastasio , =?utf-8?q?Roger_Pau_Mon?= =?utf-8?q?n=C3=A9?= Subject: [PATCH v8 03/17] xen/bitops: implement fls{l}() in common logic Date: Wed, 17 Apr 2024 12:04:46 +0200 Message-ID: <60bc710b990ed1d45741888df7e97cf25d150e61.1713347222.git.oleksii.kurochko@gmail.com> X-Mailer: git-send-email 2.44.0 In-Reply-To: References: MIME-Version: 1.0 Return type was left 'int' because of the following compilation error: ./include/xen/kernel.h:18:21: error: comparison of distinct pointer types lacks a cast [-Werror] 18 | (void) (&_x == &_y); \ | ^~ common/page_alloc.c:1843:34: note: in expansion of macro 'min' 1843 | unsigned int inc_order = min(MAX_ORDER, flsl(e - s) - 1); generic_fls{l} was used instead of __builtin_clz{l}(x) as if x is 0, the result in undefined. Signed-off-by: Oleksii Kurochko --- The patch is almost independent from Andrew's patch series ( https://lore.kernel.org/xen-devel/20240313172716.2325427-1-andrew.cooper3@citrix.com/T/#t) except test_fls() function which IMO can be merged as a separate patch after Andrew's patch will be fully ready. --- Changes in V8: - do proper rebase: back definition of fls{l} to the current patch. - drop the changes which removed ffz() in PPC. it should be done not in this patch. - add a message after Signed-off. --- Changes in V7: - Code style fixes --- Changes in V6: - new patch for the patch series. --- xen/arch/arm/include/asm/arm32/bitops.h | 2 +- xen/arch/arm/include/asm/arm64/bitops.h | 6 ++---- xen/arch/arm/include/asm/bitops.h | 7 ++----- xen/arch/ppc/include/asm/bitops.h | 3 --- xen/arch/x86/include/asm/bitops.h | 6 ++++-- xen/common/bitops.c | 22 ++++++++++++++++++++++ xen/include/xen/bitops.h | 24 ++++++++++++++++++++++++ 7 files changed, 55 insertions(+), 15 deletions(-) diff --git a/xen/arch/arm/include/asm/arm32/bitops.h b/xen/arch/arm/include/asm/arm32/bitops.h index d0309d47c1..5552d4e945 100644 --- a/xen/arch/arm/include/asm/arm32/bitops.h +++ b/xen/arch/arm/include/asm/arm32/bitops.h @@ -1,7 +1,7 @@ #ifndef _ARM_ARM32_BITOPS_H #define _ARM_ARM32_BITOPS_H -#define flsl fls +#define arch_flsl fls /* * Little endian assembly bitops. nr = 0 -> byte 0 bit 0. diff --git a/xen/arch/arm/include/asm/arm64/bitops.h b/xen/arch/arm/include/asm/arm64/bitops.h index 0efde29068..5f5d97faa0 100644 --- a/xen/arch/arm/include/asm/arm64/bitops.h +++ b/xen/arch/arm/include/asm/arm64/bitops.h @@ -22,17 +22,15 @@ static /*__*/always_inline unsigned long __ffs(unsigned long word) */ #define ffz(x) __ffs(~(x)) -static inline int flsl(unsigned long x) +static inline int arch_flsl(unsigned long x) { uint64_t ret; - if (__builtin_constant_p(x)) - return generic_flsl(x); - asm("clz\t%0, %1" : "=r" (ret) : "r" (x)); return BITS_PER_LONG - ret; } +#define arch_flsl arch_flsl /* Based on linux/include/asm-generic/bitops/find.h */ diff --git a/xen/arch/arm/include/asm/bitops.h b/xen/arch/arm/include/asm/bitops.h index 8e16335e76..860d6d4689 100644 --- a/xen/arch/arm/include/asm/bitops.h +++ b/xen/arch/arm/include/asm/bitops.h @@ -78,17 +78,14 @@ bool clear_mask16_timeout(uint16_t mask, volatile void *p, * the clz instruction for much better code efficiency. */ -static inline int fls(unsigned int x) +static inline int arch_fls(unsigned int x) { int ret; - if (__builtin_constant_p(x)) - return generic_fls(x); - asm("clz\t%"__OP32"0, %"__OP32"1" : "=r" (ret) : "r" (x)); return 32 - ret; } - +#define arch_fls arch_fls #define arch_ffs(x) ({ unsigned int __t = (x); fls(ISOLATE_LSB(__t)); }) #define arch_ffsl(x) ({ unsigned long __t = (x); flsl(ISOLATE_LSB(__t)); }) diff --git a/xen/arch/ppc/include/asm/bitops.h b/xen/arch/ppc/include/asm/bitops.h index e2b6473c8c..ca308fd62b 100644 --- a/xen/arch/ppc/include/asm/bitops.h +++ b/xen/arch/ppc/include/asm/bitops.h @@ -119,9 +119,6 @@ static inline int test_and_set_bit(unsigned int nr, volatile void *addr) (volatile unsigned int *)addr + BITOP_WORD(nr)) != 0; } -#define flsl(x) generic_flsl(x) -#define fls(x) generic_fls(x) - /* Based on linux/include/asm-generic/bitops/ffz.h */ /* * ffz - find first zero in word. diff --git a/xen/arch/x86/include/asm/bitops.h b/xen/arch/x86/include/asm/bitops.h index 2b2d9219ef..5d5b9445c5 100644 --- a/xen/arch/x86/include/asm/bitops.h +++ b/xen/arch/x86/include/asm/bitops.h @@ -430,7 +430,7 @@ static always_inline unsigned int arch_ffsl(unsigned long x) * * This is defined the same way as ffs. */ -static inline int flsl(unsigned long x) +static always_inline int arch_flsl(unsigned long x) { long r; @@ -440,8 +440,9 @@ static inline int flsl(unsigned long x) "1:" : "=r" (r) : "rm" (x)); return (int)r+1; } +#define arch_flsl arch_flsl -static inline int fls(unsigned int x) +static always_inline int arch_fls(unsigned int x) { int r; @@ -451,6 +452,7 @@ static inline int fls(unsigned int x) "1:" : "=r" (r) : "rm" (x)); return r + 1; } +#define arch_fls arch_fls /** * hweightN - returns the hamming weight of a N-bit word diff --git a/xen/common/bitops.c b/xen/common/bitops.c index a8c32f6767..95bc47176b 100644 --- a/xen/common/bitops.c +++ b/xen/common/bitops.c @@ -62,9 +62,31 @@ static void test_ffs(void) CHECK(ffs64, (uint64_t)0x8000000000000000, 64); } +static void test_fls(void) +{ + /* unsigned int ffs(unsigned int) */ + CHECK(fls, 1, 1); + CHECK(fls, 3, 2); + CHECK(fls, 3U << 30, 32); + + /* unsigned int flsl(unsigned long) */ + CHECK(flsl, 1, 1); + CHECK(flsl, 1UL << (BITS_PER_LONG - 1), BITS_PER_LONG); +#if BITS_PER_LONG > 32 + CHECK(flsl, 3UL << 32, 34); +#endif + + /* unsigned int fls64(uint64_t) */ + CHECK(fls64, 1, 1); + CHECK(fls64, 0x00000000C0000000ULL, 32); + CHECK(fls64, 0x0000000180000000ULL, 33); + CHECK(fls64, 0xC000000000000000ULL, 64); +} + static int __init cf_check test_bitops(void) { test_ffs(); + test_fls(); return 0; } diff --git a/xen/include/xen/bitops.h b/xen/include/xen/bitops.h index a41ec44064..a7edee4a95 100644 --- a/xen/include/xen/bitops.h +++ b/xen/include/xen/bitops.h @@ -196,6 +196,30 @@ static always_inline bool test_bit(int nr, const volatile void *addr) test_bit(nr, addr); \ }) +static always_inline __pure int fls(unsigned int x) +{ + if ( __builtin_constant_p(x) ) + return generic_fls(x); + +#ifndef arch_fls +#define arch_fls generic_fls +#endif + + return arch_fls(x); +} + +static always_inline __pure int flsl(unsigned long x) +{ + if ( __builtin_constant_p(x) ) + return generic_flsl(x); + +#ifndef arch_flsl +#define arch_flsl generic_flsl +#endif + + return arch_flsl(x); +} + /* * Find First Set bit. Bits are labelled from 1. */