Fix Wikipedia links containing ()

Based on: https://stackoverflow.com/questions/13824669/how-do-you-write-a-link-containing-a-closing-bracket-in-markdown-syntax

Signed-off-by: Radek Dostál <rd@radekdostal.com>

Cgroups/cgroups1.md

@@ -19,7 +19,7 @@ One `control group subsystem` represents one kind of resources like a processor
 * `freezer` - allows to suspend/resume for a task(s) from a group;
 * `net_cls` - allows to mark network packets from task(s) from a group;
 * `net_prio` - provides a way to dynamically set the priority of network traffic per network interface for a group;
-* `perf_event` - provides access to [perf events](https://en.wikipedia.org/wiki/Perf_(Linux)) to a group;
+* `perf_event` - provides access to [perf events](https://en.wikipedia.org/wiki/Perf_\(Linux\)) to a group;
 * `hugetlb` - activates support for [huge pages](https://www.kernel.org/doc/Documentation/vm/hugetlbpage.txt) for a group;
 * `pid` - sets limit to number of processes in a group.
 
@@ -174,7 +174,7 @@ print line
 ./cgroup_test_script.sh: line 5: /dev/tty: Operation not permitted
 ```
 
-Similar situation will be when you will run you [docker](https://en.wikipedia.org/wiki/Docker_(software)) containers for example:
+Similar situation will be when you will run you [docker](https://en.wikipedia.org/wiki/Docker_\(software\)) containers for example:
 
 ```
 ~$ docker ps
@@ -444,6 +444,6 @@ Links
 * [cgroups kernel documentation](https://www.kernel.org/doc/Documentation/cgroup-v1/cgroups.txt)
 * [cgroups v2](https://www.kernel.org/doc/Documentation/cgroup-v2.txt)
 * [bash](https://www.gnu.org/software/bash/)
-* [docker](https://en.wikipedia.org/wiki/Docker_(software))
-* [perf events](https://en.wikipedia.org/wiki/Perf_(Linux))
+* [docker](https://en.wikipedia.org/wiki/Docker_\(software\))
+* [perf events](https://en.wikipedia.org/wiki/Perf_\(Linux\))
 * [Previous chapter](https://0xax.gitbooks.io/linux-insides/content/MM/linux-mm-1.html)

SyncPrim/sync-6.md

@@ -4,7 +4,7 @@ Synchronization primitives in the Linux kernel. Part 6.
 Introduction
 --------------------------------------------------------------------------------
 
-This is the sixth part of the chapter which describes [synchronization primitives](https://en.wikipedia.org/wiki/Synchronization_(computer_science)) in the Linux kernel and in the previous parts we finished to consider different [readers-writer lock](https://en.wikipedia.org/wiki/Readers%E2%80%93writer_lock) synchronization primitives. We will continue to learn synchronization primitives in this part and start to consider a similar synchronization primitive which can be used to avoid the `writer starvation` problem. The name of this synchronization primitive is - `seqlock` or `sequential locks`.
+This is the sixth part of the chapter which describes [synchronization primitives](https://en.wikipedia.org/wiki/Synchronization_\(computer_science\)) in the Linux kernel and in the previous parts we finished to consider different [readers-writer lock](https://en.wikipedia.org/wiki/Readers%E2%80%93writer_lock) synchronization primitives. We will continue to learn synchronization primitives in this part and start to consider a similar synchronization primitive which can be used to avoid the `writer starvation` problem. The name of this synchronization primitive is - `seqlock` or `sequential locks`.
 
 We know from the previous [part](https://0xax.gitbooks.io/linux-insides/content/SyncPrim/sync-5.html) that [readers-writer lock](https://en.wikipedia.org/wiki/Readers%E2%80%93writer_lock) is a special lock mechanism which allows concurrent access for read-only operations, but an exclusive lock is needed for writing or modifying data. As we may guess, it may lead to a problem which is called `writer starvation`. In other words, a writer process can't acquire a lock as long as at least one reader process which acquired a lock holds it. So, in the situation when contention is high, it will lead to situation when a writer process which wants to acquire a lock will wait for it for a long time.
 
@@ -321,7 +321,7 @@ static inline void write_sequnlock_irq(seqlock_t *sl)
 
 As we may see, these functions differ only in the initialization of spinlock. They call `spin_lock_irq` and `spin_unlock_irq` instead of `spin_lock` and `spin_unlock`.
 
-Or for example `write_seqlock_irqsave` and `write_sequnlock_irqrestore` functions which are the same but used `spin_lock_irqsave` and `spin_unlock_irqsave` macro to use in [IRQ](https://en.wikipedia.org/wiki/Interrupt_request_(PC_architecture)) handlers.
+Or for example `write_seqlock_irqsave` and `write_sequnlock_irqrestore` functions which are the same but used `spin_lock_irqsave` and `spin_unlock_irqsave` macro to use in [IRQ](https://en.wikipedia.org/wiki/Interrupt_request_\(PC_architecture\)) handlers.
 
 That's all.
 
@@ -337,7 +337,7 @@ If you have questions or suggestions, feel free to ping me in twitter [0xAX](htt
 Links
 --------------------------------------------------------------------------------
 
-* [synchronization primitives](https://en.wikipedia.org/wiki/Synchronization_(computer_science))
+* [synchronization primitives](https://en.wikipedia.org/wiki/Synchronization_\(computer_science\))
 * [readers-writer lock](https://en.wikipedia.org/wiki/Readers%E2%80%93writer_lock) 
 * [spinlock](https://0xax.gitbooks.io/linux-insides/content/SyncPrim/sync-1.html)
 * [critical section](https://en.wikipedia.org/wiki/Critical_section)
@@ -348,5 +348,5 @@ Links
 * [Timers and time management in the Linux kernel](https://0xax.gitbooks.io/linux-insides/content/Timers/)
 * [interrupt handlers](https://en.wikipedia.org/wiki/Interrupt_handler)
 * [softirq](https://0xax.gitbooks.io/linux-insides/content/interrupts/interrupts-9.html)
-* [IRQ](https://en.wikipedia.org/wiki/Interrupt_request_(PC_architecture))
+* [IRQ](https://en.wikipedia.org/wiki/Interrupt_request_\(PC_architecture\))
 * [Previous part](https://0xax.gitbooks.io/linux-insides/content/SyncPrim/sync-5.html)

SysCall/syscall-5.md

@@ -216,7 +216,7 @@ At the next step we check that a file is not tried to be opened via [fanotify](h
 flags &= ~FMODE_NONOTIFY & ~O_CLOEXEC;
 ```
 
-We do this to not leak a [file descriptor](https://en.wikipedia.org/wiki/File_descriptor). By default, the new file descriptor is set to remain open across an `execve` system call, but the `open` system call supports `O_CLOEXEC` flag that can be used to change this default behaviour. So we do this to prevent leaking of a file descriptor when one thread opens a file to set `O_CLOEXEC` flag and in the same time the second process does a [fork](https://en.wikipedia.org/wiki/Fork_(system_call)) + [execve](https://en.wikipedia.org/wiki/Exec_(system_call)) and as you may remember that child will have copies of the parent's set of open file descriptors.
+We do this to not leak a [file descriptor](https://en.wikipedia.org/wiki/File_descriptor). By default, the new file descriptor is set to remain open across an `execve` system call, but the `open` system call supports `O_CLOEXEC` flag that can be used to change this default behaviour. So we do this to prevent leaking of a file descriptor when one thread opens a file to set `O_CLOEXEC` flag and in the same time the second process does a [fork](https://en.wikipedia.org/wiki/Fork_\(system_call\)) + [execve](https://en.wikipedia.org/wiki/Exec_\(system_call\)) and as you may remember that child will have copies of the parent's set of open file descriptors.
 
 At the next step we check that if our flags contains `O_SYNC` flag, we apply `O_DSYNC` flag too:
 
@@ -393,8 +393,8 @@ Links
 * [x86_64](https://en.wikipedia.org/wiki/X86-64)
 * [opendir](http://man7.org/linux/man-pages/man3/opendir.3.html)
 * [fanotify](http://man7.org/linux/man-pages/man7/fanotify.7.html)
-* [fork](https://en.wikipedia.org/wiki/Fork_(system_call))
-* [execve](https://en.wikipedia.org/wiki/Exec_(system_call))
+* [fork](https://en.wikipedia.org/wiki/Fork_\(system_call\))
+* [execve](https://en.wikipedia.org/wiki/Exec_\(system_call\))
 * [symlink](https://en.wikipedia.org/wiki/Symbolic_link)
 * [audit](https://linux.die.net/man/8/auditd)
 * [inode](https://en.wikipedia.org/wiki/Inode)