Date: Sun, 25 Feb 2018 10:14:35 +0000 (UTC) From: Hans Petter Selasky <hselasky@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-stable@freebsd.org, svn-src-stable-11@freebsd.org Subject: svn commit: r329951 - stable/11/sys/compat/linuxkpi/common/include/asm Message-ID: <201802251014.w1PAEZTa007024@repo.freebsd.org>
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Author: hselasky Date: Sun Feb 25 10:14:35 2018 New Revision: 329951 URL: https://svnweb.freebsd.org/changeset/base/329951 Log: MFC r329371: Allow the cmpxchg() macro in the LinuxKPI to work on pointers without generating compiler warnings, -Wint-conversion . Requested by: Johannes Lundberg <johalun0@gmail.com> Sponsored by: Mellanox Technologies Modified: stable/11/sys/compat/linuxkpi/common/include/asm/atomic.h Directory Properties: stable/11/ (props changed) Modified: stable/11/sys/compat/linuxkpi/common/include/asm/atomic.h ============================================================================== --- stable/11/sys/compat/linuxkpi/common/include/asm/atomic.h Sun Feb 25 08:56:44 2018 (r329950) +++ stable/11/sys/compat/linuxkpi/common/include/asm/atomic.h Sun Feb 25 10:14:35 2018 (r329951) @@ -159,36 +159,41 @@ atomic_cmpxchg(atomic_t *v, int old, int new) return (ret); } -#define cmpxchg(ptr, old, new) ({ \ - __typeof(*(ptr)) __ret; \ - \ - CTASSERT(sizeof(__ret) == 1 || sizeof(__ret) == 2 || \ - sizeof(__ret) == 4 || sizeof(__ret) == 8); \ - \ - __ret = (old); \ - switch (sizeof(__ret)) { \ - case 1: \ - while (!atomic_fcmpset_8((volatile int8_t *)(ptr), \ - (int8_t *)&__ret, (new)) && __ret == (old)) \ - ; \ - break; \ - case 2: \ - while (!atomic_fcmpset_16((volatile int16_t *)(ptr), \ - (int16_t *)&__ret, (new)) && __ret == (old)) \ - ; \ - break; \ - case 4: \ - while (!atomic_fcmpset_32((volatile int32_t *)(ptr), \ - (int32_t *)&__ret, (new)) && __ret == (old)) \ - ; \ - break; \ - case 8: \ - while (!atomic_fcmpset_64((volatile int64_t *)(ptr), \ - (int64_t *)&__ret, (new)) && __ret == (old)) \ - ; \ - break; \ - } \ - __ret; \ +#define cmpxchg(ptr, old, new) ({ \ + union { \ + __typeof(*(ptr)) val; \ + u8 u8[]; \ + u16 u16[]; \ + u32 u32[]; \ + u64 u64[]; \ + } __ret = { .val = (old) }, __new = { .val = (new) }; \ + \ + CTASSERT(sizeof(__ret.val) == 1 || sizeof(__ret.val) == 2 || \ + sizeof(__ret.val) == 4 || sizeof(__ret.val) == 8); \ + \ + switch (sizeof(__ret.val)) { \ + case 1: \ + while (!atomic_fcmpset_8((volatile u8 *)(ptr), \ + __ret.u8, __new.u8[0]) && __ret.val == (old)) \ + ; \ + break; \ + case 2: \ + while (!atomic_fcmpset_16((volatile u16 *)(ptr), \ + __ret.u16, __new.u16[0]) && __ret.val == (old)) \ + ; \ + break; \ + case 4: \ + while (!atomic_fcmpset_32((volatile u32 *)(ptr), \ + __ret.u32, __new.u32[0]) && __ret.val == (old)) \ + ; \ + break; \ + case 8: \ + while (!atomic_fcmpset_64((volatile u64 *)(ptr), \ + __ret.u64, __new.u64[0]) && __ret.val == (old)) \ + ; \ + break; \ + } \ + __ret.val; \ }) #define cmpxchg_relaxed(...) cmpxchg(__VA_ARGS__)
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