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Add table for FreeRTOS scheduling algorithm configuration #83

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add table for scheduler configuration
kar-rahul-aws Mar 8, 2024
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kar-rahul-aws Mar 14, 2024
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50 changes: 28 additions & 22 deletions ch04.md
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Expand Up @@ -1319,25 +1319,25 @@ observed behavior given by the execution sequence shown in Figure 4.12.
Continuous task 2 running
Continuous task 2 running
Periodic task is running
Continuous task 1 is running
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Expand Down Expand Up @@ -2159,15 +2159,21 @@ scheduling algorithm does not guarantee time is shared equally between
tasks of equal priority, only that *Ready* state tasks of equal priority
enter the *Running* state in turn.

<a name="tbl5" title="Table 5 The FreeRTOSConfig.h settings to configure the kernel scheduling algorithms"></a>

***
| Scheduling Algorithm | Prioritized | `configUSE_PREEMPTION` | `configUSE_TIME_SLICING` |
|---------------------------------|-------------|------------------------|--------------------------|
| Preemptive With Time Slicing | Yes | 1 | 1 |
| Preemptive Without Time Slicing | Yes | 1 | 0 |
| Co-Operative | No | 0 | Any |

***Table 5*** *The FreeRTOSConfig.h settings to configure the kernel scheduling algorithms*
* * *

### 4.12.3 Prioritized Preemptive Scheduling with Time Slicing

The configuration shown in the table below sets the FreeRTOS scheduler to use a
The configuration shown in the Table 5 sets the FreeRTOS scheduler to use a
scheduling algorithm called 'Fixed Priority Preemptive Scheduling with
Time Slicing', which is the scheduling algorithm used by most small RTOS
applications, and the algorithm used by all the examples presented in
Expand Down Expand Up @@ -2345,7 +2351,7 @@ same task selection and preemption algorithms as described in the
previous section, but does not use time slicing to share processing time
between tasks of equal priority.

The table below shows the FreeRTOSConfig.h settings that configure the FreeRTOS
The Table 5 shows the FreeRTOSConfig.h settings that configure the FreeRTOS
scheduler to use prioritized preemptive scheduling without time slicing.

As was demonstrated in Figure 4.19, if time slicing is used, and there is
Expand Down Expand Up @@ -2419,7 +2425,7 @@ Referring to Figure 4.21, which assumes `configIDLE_SHOULD_YIELD` is set to 0:
### 4.12.5 Cooperative Scheduling

This book focuses on preemptive scheduling, but FreeRTOS can also use
cooperative scheduling. The table below shows the FreeRTOSConfig.h settings
cooperative scheduling. The Table 5 shows the FreeRTOSConfig.h settings
that configure the FreeRTOS scheduler to use cooperative scheduling.

When using the cooperative scheduler (and therefore assuming
Expand Down
12 changes: 6 additions & 6 deletions ch09.md
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Expand Up @@ -365,12 +365,12 @@ A task will not enter the Blocked state if its unblock condition is met
at the time `xEventGroupWaitBits()` is called.

Examples of conditions that will result in a task either entering the
Blocked state, or exiting the Blocked state, are provided in Table 5.
Table 5 only shows the least significant four binary bits of the event
Blocked state, or exiting the Blocked state, are provided in Table 6.
Table 6 only shows the least significant four binary bits of the event
group and uxBitsToWaitFor values—the other bits of those two values are
assumed to be zero.

<a name="tbl5" title="Table 5 The Effect of the uxBitsToWaitFor and xWaitForAllBits Parameters"></a>
<a name="tbl6" title="Table 6 The Effect of the uxBitsToWaitFor and xWaitForAllBits Parameters"></a>

* * *
| Existing Event Group Value | uxBitsToWaitFor value | xWaitForAllBits value | Resultant Behavior |
Expand All @@ -380,7 +380,7 @@ assumed to be zero.
| 0100 | 0110 | pdFALSE | The calling task will not enter the Blocked state because xWaitForAllBits is pdFALSE, and one of the two bits specified by uxBitsToWaitFor is already set in the event group. |
| 0100 | 0110 | pdTRUE | The calling task will enter the Blocked state because xWaitForAllBits is pdTRUE, and only one of the two bits specified by uxBitsToWaitFor is already set in the event group. The task will leave the Blocked state when both bit 1 and bit 2 are set in the event group. |

***Table 5*** *The Effect of the uxBitsToWaitFor and xWaitForAllBits Parameters*
***Table 6*** *The Effect of the uxBitsToWaitFor and xWaitForAllBits Parameters*
* * *

The calling task specifies bits to test using the `uxBitsToWaitFor`
Expand Down Expand Up @@ -414,7 +414,7 @@ operation (uninterruptable by other tasks or interrupts).

For example, if the calling task wants to wait for event bit 0 and/or
event bit 2 to become set in the event group, then set `uxBitsToWaitFor`
to 0x05 (binary 0101). Refer to Table 5 for further examples.
to 0x05 (binary 0101). Refer to Table 6 for further examples.

- `xClearOnExit`

Expand Down Expand Up @@ -446,7 +446,7 @@ operation (uninterruptable by other tasks or interrupts).
`uxBitsToWaitFor` are set (or the timeout specified by the `xTicksToWait`
parameter expires).

Refer to Table 5 for examples.
Refer to Table 6 for examples.

- `xTicksToWait`

Expand Down
3 changes: 2 additions & 1 deletion toc.md
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Expand Up @@ -603,4 +603,5 @@
+ [Table 2 TickType\_t data type and the configTICK\_TYPE\_WIDTH\_IN\_BITS configuration](ch02.md#tbl2)
+ [Table 3 Macro prefixes](ch02.md#tbl3)
+ [Table 4 Common macro definitions](ch02.md#tbl4)
+ [Table 5 The Effect of the uxBitsToWaitFor and xWaitForAllBits Parameters](ch09.md#tbl5)
+ [Table 5 The FreeRTOSConfig.h settings to configure the kernel scheduling algorithms](ch04.md#tbl5)
+ [Table 6 The Effect of the uxBitsToWaitFor and xWaitForAllBits Parameters](ch09.md#tbl6)