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(cst-prg-69-142.cust.vodafone.cz. [46.135.69.142]) by smtp.gmail.com with ESMTPSA id a640c23a62f3a-acb3d128c9esm194762866b.108.2025.04.16.15.16.37 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 16 Apr 2025 15:16:39 -0700 (PDT) From: Mateusz Guzik To: brauner@kernel.org Cc: torvalds@linux-foundation.org, viro@zeniv.linux.org.uk, jack@suse.cz, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, Mateusz Guzik Subject: [PATCH 1/2] fs: touch up predicts in inode_permission() Date: Thu, 17 Apr 2025 00:16:25 +0200 Message-ID: <20250416221626.2710239-2-mjguzik@gmail.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20250416221626.2710239-1-mjguzik@gmail.com> References: <20250416221626.2710239-1-mjguzik@gmail.com> Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 The routine only encounters errors when people try to access things they can't, which is a negligible amount of calls. The only questionable bit might be the pre-existing predict around MAY_WRITE. Currently the routine is predominantly used for MAY_EXEC, so this makes some sense. I verified this straightens out the asm. Signed-off-by: Mateusz Guzik --- fs/namei.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/fs/namei.c b/fs/namei.c index daebc307c1a3..cff69c12d6fd 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -571,14 +571,14 @@ int inode_permission(struct mnt_idmap *idmap, int retval; retval = sb_permission(inode->i_sb, inode, mask); - if (retval) + if (unlikely(retval)) return retval; if (unlikely(mask & MAY_WRITE)) { /* * Nobody gets write access to an immutable file. */ - if (IS_IMMUTABLE(inode)) + if (unlikely(IS_IMMUTABLE(inode))) return -EPERM; /* @@ -586,16 +586,16 @@ int inode_permission(struct mnt_idmap *idmap, * written back improperly if their true value is unknown * to the vfs. */ - if (HAS_UNMAPPED_ID(idmap, inode)) + if (unlikely(HAS_UNMAPPED_ID(idmap, inode))) return -EACCES; } retval = do_inode_permission(idmap, inode, mask); - if (retval) + if (unlikely(retval)) return retval; retval = devcgroup_inode_permission(inode, mask); - if (retval) + if (unlikely(retval)) return retval; return security_inode_permission(inode, mask);