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<div class=" wh_topic_content body "><main role="main"><article class="- topic/topic concept/concept topic concept" role="article" aria-labelledby="ariaid-title1"><span class="edit-link" style="font-size:12px; opacity:0.6; text-align:right; vertical-align:middle"><a target="_blank" href="http://172.16.35.88/tasks/jdssno1uvvbf2mltu9kb9v3if05d5gopuakboe8hlud18rma/edit/F:/aicdita/aicdita-cn/topics/sdk/mpp/mpp-heap_interface_intro.dita">Edit online</a></span><h1 class="- topic/title title topictitle1" id="ariaid-title1">MPP Heap 接口说明</h1><div class="date inPage">2 Dec 2024</div><div style="color: gray;">
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Read time: 3 minute(s)
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</div><div class="- topic/body concept/conbody body conbody"><p class="- topic/p p" data-ofbid="d354393e22__20250121172132">Mpp Heap 负责管理 mpp 中间件独占的 CMA 内存，并在 mpp 中间件需要物理内存时，将内存页面导出为 DMA-BUF。</p><section class="- topic/section section" id="mpp_heap_interface_intro__section_l31_nwh_d1c" data-ofbid="mpp_heap_interface_intro__section_l31_nwh_d1c"><h2 class="- topic/title title sectiontitle">mpp heap 特点</h2>
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<p class="- topic/p p" data-ofbid="d354393e29__20250121172132"><strong class="+ topic/ph hi-d/b ph b">解决内存碎片化</strong></p>
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<p class="- topic/p p" data-ofbid="d354393e33__20250121172132">CMA 内存允许多媒体模块和系统复用，在这种情况下，内存碎片化的情况不可避免（部分内存页面可能会被系统 pin 住，无法迁移）。而 mpp heap 管理的内存能确保只被
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mpp 中间件使用，避免了内存页面被 pin 住而导致碎片化的问题。</p>
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<ul class="- topic/ul ul" id="mpp_heap_interface_intro__ul_m31_nwh_d1c" data-ofbid="mpp_heap_interface_intro__ul_m31_nwh_d1c"><li class="- topic/li li" data-ofbid="d354393e37__20250121172132">
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<p class="- topic/p p" data-ofbid="d354393e39__20250121172132">mpp heap 的内存需要在用户态通过 <code class="+ topic/ph pr-d/codeph ph codeph">/dev/dmabuf/mpp</code> 节点来申请，这个节点是 ArtInChip
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平台扩展的私有节点，只有 mpp 中间件会访问。</p>
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</li><li class="- topic/li li" data-ofbid="d354393e45__20250121172132">
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<p class="- topic/p p" data-ofbid="d354393e47__20250121172132">对于系统来说，该块内存已被 alloc，系统不会再去访问，因此能达到 mpp 中间件独占的效果。</p>
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</li></ul>
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<div class="- topic/note note tip note_tip" id="mpp_heap_interface_intro__note_hsq_5wh_d1c" data-ofbid="mpp_heap_interface_intro__note_hsq_5wh_d1c"><span class="note__title">提示：</span>
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<p class="- topic/p p" data-ofbid="d354393e53__20250121172132">只要在调用 mpp 中间件的过程中，只要做到资源的申请与释放一一对应，就能解决内存碎片化问题。</p>
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</div>
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<p class="- topic/p p" data-ofbid="d354393e58__20250121172132"><strong class="+ topic/ph hi-d/b ph b">允许系统回收 mpp heap 内存</strong></p>
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<p class="- topic/p p" data-ofbid="d354393e62__20250121172132">mpp heap 管理的内存通过 <code class="+ topic/ph pr-d/codeph ph codeph">cma_alloc</code> 申请，在系统内存资源紧张，而又不需要 mpp 中间件的情况下 （例如 OTA
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升级），允许通过销毁 mpp heap 释放 CMA 内存给系统使用。</p>
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<div class="- topic/note note note note_note" id="mpp_heap_interface_intro__note_cbb_vwh_d1c" data-ofbid="mpp_heap_interface_intro__note_cbb_vwh_d1c"><span class="note__title">注：</span>
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<p class="- topic/p p" data-ofbid="d354393e70__20250121172132">mpp heap 一旦销毁，无法再次初始化，只能 reboot 系统。</p>
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</div>
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</section><section class="- topic/section section" id="mpp_heap_interface_intro__section_n31_nwh_d1c" data-ofbid="mpp_heap_interface_intro__section_n31_nwh_d1c"><h2 class="- topic/title title sectiontitle">mpp heap init</h2>
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<p class="- topic/p p" data-ofbid="d354393e79__20250121172132">初始化时，MPP Heap 从 CMA 内存中申请一大块物理连续内存，并创建一个 genpool 内存池进行管理。</p>
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<figure class="- topic/fig fig fignone" id="mpp_heap_interface_intro__fig_o3p_twh_d1c" data-ofbid="mpp_heap_interface_intro__fig_o3p_twh_d1c"><br/><div class="imagecenter"><img class="- topic/image image imagecenter" id="mpp_heap_interface_intro__image_o31_nwh_d1c" src="../../../images/mpp/mpp_heap_init.png" alt="mpp_heap_init"/></div><br/><figcaption data-caption-side="bottom" class="- topic/title title figcapcenter"><span class="figtitleprefix fig--title-label">图<span class="fig--title-label-number"> 1</span><span class="fig--title-label-punctuation">. </span></span><span class="fig--title">mpp_heap 初始化</span></figcaption></figure>
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</section><section class="- topic/section section" id="mpp_heap_interface_intro__section_p31_nwh_d1c" data-ofbid="mpp_heap_interface_intro__section_p31_nwh_d1c"><h2 class="- topic/title title sectiontitle">mpp heap export</h2>
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<p class="- topic/p p" data-ofbid="d354393e94__20250121172132">mpp heap 通过 <code class="+ topic/ph pr-d/codeph ph codeph">/dev/dmabuf/mpp</code> 节点，以 <code class="+ topic/ph pr-d/codeph ph codeph">ioctl</code> 的方式将管理的 CMA
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内存导出为标准的 DMA-BUF 文件句柄。</p>
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<p class="- topic/p p" data-ofbid="d354393e103__20250121172132">genpool 内存池是一个基于 bitmap 的管理算法，其最小分配单位为 4K，分配的内存无论 <strong class="+ topic/ph hi-d/b ph b">首地址</strong> 还是 <strong class="+ topic/ph hi-d/b ph b">大小</strong> ，都遵循
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<code class="+ topic/ph pr-d/codeph ph codeph">4K</code> 对齐。</p>
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<figure class="- topic/fig fig fignone" id="mpp_heap_interface_intro__fig_hcr_swh_d1c" data-ofbid="mpp_heap_interface_intro__fig_hcr_swh_d1c"><br/><div class="imagecenter"><img class="- topic/image image imagecenter" id="mpp_heap_interface_intro__image_q31_nwh_d1c" src="../../../images/mpp/mpp_heap_export.png" alt="mpp_heap_export"/></div><br/><figcaption data-caption-side="bottom" class="- topic/title title figcapcenter"><span class="figtitleprefix fig--title-label">图<span class="fig--title-label-number"> 2</span><span class="fig--title-label-punctuation">. </span></span><span class="fig--title">mpp_heap 导出 DMA-BUF</span></figcaption></figure>
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</section><section class="- topic/section section" id="mpp_heap_interface_intro__section_r31_nwh_d1c" data-ofbid="mpp_heap_interface_intro__section_r31_nwh_d1c"><h2 class="- topic/title title sectiontitle">mpp heap close</h2>
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<p class="- topic/p p" data-ofbid="d354393e127__20250121172132">只需要 <code class="+ topic/ph pr-d/codeph ph codeph">close</code> DMA-BUF 的文件句柄，即触发 mpp heap 的回收 DMA-BUF。</p>
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<div class="- topic/note note note note_note" id="mpp_heap_interface_intro__note_acy_rwh_d1c" data-ofbid="mpp_heap_interface_intro__note_acy_rwh_d1c"><span class="note__title">注：</span>
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<p class="- topic/p p" data-ofbid="d354393e135__20250121172132">当一块 DMA-BUF 还被多媒体模块占用时，close 操作无法触发 mpp heap 回收</p>
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</div>
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<figure class="- topic/fig fig fignone" id="mpp_heap_interface_intro__fig_lp3_rwh_d1c" data-ofbid="mpp_heap_interface_intro__fig_lp3_rwh_d1c"><br/><div class="imagecenter"><img class="- topic/image image imagecenter" id="mpp_heap_interface_intro__image_s31_nwh_d1c" src="../../../images/mpp/mpp_heap_close.png" alt="mpp_heap_close"/></div><br/><figcaption data-caption-side="bottom" class="- topic/title title figcapcenter"><span class="figtitleprefix fig--title-label">图<span class="fig--title-label-number"> 3</span><span class="fig--title-label-punctuation">. </span></span><span class="fig--title">mpp_heap 回收 DMA-BUF</span></figcaption></figure>
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</section><section class="- topic/section section" id="mpp_heap_interface_intro__section_t31_nwh_d1c" data-ofbid="mpp_heap_interface_intro__section_t31_nwh_d1c"><h2 class="- topic/title title sectiontitle">mpp heap destroy</h2>
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<p class="- topic/p p" data-ofbid="d354393e151__20250121172132">通过 <code class="+ topic/ph pr-d/codeph ph codeph">/dev/dmabuf/mpp</code> 节点，下发扩展的 <code class="+ topic/ph pr-d/codeph ph codeph">ioctl</code> 接口即可销毁 MPP Heap,
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将其中的 CMA 内存归还改系统。</p>
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<p class="- topic/p p" data-ofbid="d354393e160__20250121172132">mpp heap 一旦被销毁，无法再次初始化，只能 reboot。</p>
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<figure class="- topic/fig fig fignone" id="mpp_heap_interface_intro__fig_ptm_qwh_d1c" data-ofbid="mpp_heap_interface_intro__fig_ptm_qwh_d1c"><br/><div class="imagecenter"><img class="- topic/image image imagecenter" id="mpp_heap_interface_intro__image_u31_nwh_d1c" src="../../../images/mpp/mpp_heap_destroy.png" alt="mpp_heap_destroy"/></div><br/><figcaption data-caption-side="bottom" class="- topic/title title figcapcenter"><span class="figtitleprefix fig--title-label">图<span class="fig--title-label-number"> 4</span><span class="fig--title-label-punctuation">. </span></span><span class="fig--title">mpp heap 销毁</span></figcaption></figure>
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</section><section class="- topic/section section" id="mpp_heap_interface_intro__section_v31_nwh_d1c" data-ofbid="mpp_heap_interface_intro__section_v31_nwh_d1c"><h2 class="- topic/title title sectiontitle">mpp heap 接口</h2>
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<p class="- topic/p p" data-ofbid="d354393e175__20250121172132">接口如下 :</p>
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<pre class="+ topic/pre pr-d/codeblock pre codeblock language-c" id="mpp_heap_interface_intro__pre_w31_nwh_d1c" data-ofbid="mpp_heap_interface_intro__pre_w31_nwh_d1c">intdmabuf_device_open();voiddmabuf_device_close(intdma_fd);voiddmabuf_device_destroy(intdma_fd);intdmabuf_alloc(intdma_fd,intsize);</pre>
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<div class="table-container"><table class="- topic/table table frame-all" id="mpp_heap_interface_intro__table_x31_nwh_d1c" data-ofbid="mpp_heap_interface_intro__table_x31_nwh_d1c" data-cols="2"><caption></caption><colgroup><col style="width:50%"/><col style="width:50%"/></colgroup><thead class="- topic/thead thead"><tr class="- topic/row"><th class="- topic/entry entry colsep-1 rowsep-1" id="mpp_heap_interface_intro__table_x31_nwh_d1c__entry__1">函数原型</th><th class="- topic/entry entry colsep-0 rowsep-1" id="mpp_heap_interface_intro__table_x31_nwh_d1c__entry__2">int dmabuf_device_open()</th></tr></thead><tbody class="- topic/tbody tbody"><tr class="- topic/row"><td class="- topic/entry entry colsep-1 rowsep-1" headers="mpp_heap_interface_intro__table_x31_nwh_d1c__entry__1">功能说明</td><td class="- topic/entry entry colsep-0 rowsep-1" headers="mpp_heap_interface_intro__table_x31_nwh_d1c__entry__2">获取 mpp heap 的文件句柄</td></tr><tr class="- topic/row"><td class="- topic/entry entry colsep-1 rowsep-1" headers="mpp_heap_interface_intro__table_x31_nwh_d1c__entry__1">参数定义</td><td class="- topic/entry entry colsep-0 rowsep-1" headers="mpp_heap_interface_intro__table_x31_nwh_d1c__entry__2">void</td></tr><tr class="- topic/row"><td class="- topic/entry entry colsep-1 rowsep-1" headers="mpp_heap_interface_intro__table_x31_nwh_d1c__entry__1">返回值</td><td class="- topic/entry entry colsep-0 rowsep-1" headers="mpp_heap_interface_intro__table_x31_nwh_d1c__entry__2">dma_fd:成功<0:失败</td></tr><tr class="- topic/row"><td class="- topic/entry entry colsep-1 rowsep-0" headers="mpp_heap_interface_intro__table_x31_nwh_d1c__entry__1">注意事项</td><td class="- topic/entry entry colsep-0 rowsep-0" headers="mpp_heap_interface_intro__table_x31_nwh_d1c__entry__2">-</td></tr></tbody></table></div>
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<div class="table-container"><table class="- topic/table table frame-all" id="mpp_heap_interface_intro__table_y31_nwh_d1c" data-ofbid="mpp_heap_interface_intro__table_y31_nwh_d1c" data-cols="2"><caption></caption><colgroup><col style="width:25%"/><col style="width:75%"/></colgroup><thead class="- topic/thead thead"><tr class="- topic/row"><th class="- topic/entry entry colsep-1 rowsep-1" id="mpp_heap_interface_intro__table_y31_nwh_d1c__entry__1">函数原型</th><th class="- topic/entry entry colsep-0 rowsep-1" id="mpp_heap_interface_intro__table_y31_nwh_d1c__entry__2">void dmabuf_device_close(int dma_fd)</th></tr></thead><tbody class="- topic/tbody tbody"><tr class="- topic/row"><td class="- topic/entry entry colsep-1 rowsep-1" headers="mpp_heap_interface_intro__table_y31_nwh_d1c__entry__1">功能说明</td><td class="- topic/entry entry colsep-0 rowsep-1" headers="mpp_heap_interface_intro__table_y31_nwh_d1c__entry__2">释放 mpp heap 的文件句柄</td></tr><tr class="- topic/row"><td class="- topic/entry entry colsep-1 rowsep-1" headers="mpp_heap_interface_intro__table_y31_nwh_d1c__entry__1">参数定义</td><td class="- topic/entry entry colsep-0 rowsep-1" headers="mpp_heap_interface_intro__table_y31_nwh_d1c__entry__2">dma_fd: mpp heap 的文件句柄</td></tr><tr class="- topic/row"><td class="- topic/entry entry colsep-1 rowsep-1" headers="mpp_heap_interface_intro__table_y31_nwh_d1c__entry__1">返回值</td><td class="- topic/entry entry colsep-0 rowsep-1" headers="mpp_heap_interface_intro__table_y31_nwh_d1c__entry__2">void</td></tr><tr class="- topic/row"><td class="- topic/entry entry colsep-1 rowsep-0" headers="mpp_heap_interface_intro__table_y31_nwh_d1c__entry__1">注意事项</td><td class="- topic/entry entry colsep-0 rowsep-0" headers="mpp_heap_interface_intro__table_y31_nwh_d1c__entry__2">-</td></tr></tbody></table></div>
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<div class="table-container"><table class="- topic/table table frame-all" id="mpp_heap_interface_intro__table_z31_nwh_d1c" data-ofbid="mpp_heap_interface_intro__table_z31_nwh_d1c" data-cols="2"><caption></caption><colgroup><col style="width:25%"/><col style="width:75%"/></colgroup><thead class="- topic/thead thead"><tr class="- topic/row"><th class="- topic/entry entry colsep-1 rowsep-1" id="mpp_heap_interface_intro__table_z31_nwh_d1c__entry__1">函数原型</th><th class="- topic/entry entry colsep-0 rowsep-1" id="mpp_heap_interface_intro__table_z31_nwh_d1c__entry__2">void dmabuf_device_destroy(int dma_fd)</th></tr></thead><tbody class="- topic/tbody tbody"><tr class="- topic/row"><td class="- topic/entry entry colsep-1 rowsep-1" headers="mpp_heap_interface_intro__table_z31_nwh_d1c__entry__1">功能说明</td><td class="- topic/entry entry colsep-0 rowsep-1" headers="mpp_heap_interface_intro__table_z31_nwh_d1c__entry__2">销毁 mpp heap</td></tr><tr class="- topic/row"><td class="- topic/entry entry colsep-1 rowsep-1" headers="mpp_heap_interface_intro__table_z31_nwh_d1c__entry__1">参数定义</td><td class="- topic/entry entry colsep-0 rowsep-1" headers="mpp_heap_interface_intro__table_z31_nwh_d1c__entry__2">dma_fd: mpp heap 的文件句柄</td></tr><tr class="- topic/row"><td class="- topic/entry entry colsep-1 rowsep-1" headers="mpp_heap_interface_intro__table_z31_nwh_d1c__entry__1">返回值</td><td class="- topic/entry entry colsep-0 rowsep-1" headers="mpp_heap_interface_intro__table_z31_nwh_d1c__entry__2">void</td></tr><tr class="- topic/row"><td class="- topic/entry entry colsep-1 rowsep-0" headers="mpp_heap_interface_intro__table_z31_nwh_d1c__entry__1">注意事项</td><td class="- topic/entry entry colsep-0 rowsep-0" headers="mpp_heap_interface_intro__table_z31_nwh_d1c__entry__2">mpp heap 一旦被销毁，无法再次初始化，只能 reboot</td></tr></tbody></table></div>
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<div class="table-container"><table class="- topic/table table frame-all" id="mpp_heap_interface_intro__table_aj1_nwh_d1c" data-ofbid="mpp_heap_interface_intro__table_aj1_nwh_d1c" data-cols="2"><caption></caption><colgroup><col style="width:25%"/><col style="width:75%"/></colgroup><thead class="- topic/thead thead"><tr class="- topic/row"><th class="- topic/entry entry colsep-1 rowsep-1" id="mpp_heap_interface_intro__table_aj1_nwh_d1c__entry__1">函数原型</th><th class="- topic/entry entry colsep-0 rowsep-1" id="mpp_heap_interface_intro__table_aj1_nwh_d1c__entry__2">int dmabuf_alloc(int dma_fd, int size)</th></tr></thead><tbody class="- topic/tbody tbody"><tr class="- topic/row"><td class="- topic/entry entry colsep-1 rowsep-1" headers="mpp_heap_interface_intro__table_aj1_nwh_d1c__entry__1">功能说明</td><td class="- topic/entry entry colsep-0 rowsep-1" headers="mpp_heap_interface_intro__table_aj1_nwh_d1c__entry__2">通过 mpp heap 申请一块 DMA-BUF</td></tr><tr class="- topic/row"><td class="- topic/entry entry colsep-1 rowsep-1" headers="mpp_heap_interface_intro__table_aj1_nwh_d1c__entry__1">参数定义</td><td class="- topic/entry entry colsep-0 rowsep-1" headers="mpp_heap_interface_intro__table_aj1_nwh_d1c__entry__2">dma_fd: mpp heap 的文件句柄 size: DMA-BUF size</td></tr><tr class="- topic/row"><td class="- topic/entry entry colsep-1 rowsep-1" headers="mpp_heap_interface_intro__table_aj1_nwh_d1c__entry__1">返回值</td><td class="- topic/entry entry colsep-0 rowsep-1" headers="mpp_heap_interface_intro__table_aj1_nwh_d1c__entry__2">DMA-BUF fd:成功<0:失败</td></tr><tr class="- topic/row"><td class="- topic/entry entry colsep-1 rowsep-0" headers="mpp_heap_interface_intro__table_aj1_nwh_d1c__entry__1">注意事项</td><td class="- topic/entry entry colsep-0 rowsep-0" headers="mpp_heap_interface_intro__table_aj1_nwh_d1c__entry__2">-</td></tr></tbody></table></div>
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</section><section class="- topic/section section" id="mpp_heap_interface_intro__section_bj1_nwh_d1c" data-ofbid="mpp_heap_interface_intro__section_bj1_nwh_d1c"><h2 class="- topic/title title sectiontitle">mpp heap 设置</h2>
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<p class="- topic/p p" data-ofbid="d354393e315__20250121172132">mpp heap 管理的内存必须满足视频播放的最大需求。</p>
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<p class="- topic/p p" data-ofbid="d354393e318__20250121172132">视频播放内存可由 <a class="- topic/xref xref" href="../../../out/external-references/video_memory.html">video memory</a>得到结果。</p>
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<p class="- topic/p p" data-ofbid="d354393e325__20250121172132">mpp heap 中的内存从 CMA 预留内存中申请，但 CMA 内存不能只为 mpp heap 预留，还需要为
|
||
其他需要物理连续内存的模块预留，主要是显示，音频和通讯模块。</p>
|
||
<p class="- topic/p p" data-ofbid="d354393e328__20250121172132">注解</p>
|
||
<p class="- topic/p p" data-ofbid="d354393e332__20250121172132">如果 mpp heap 的 size 或 CMA 预留内存的 size 设置不合理，不仅影响 mpp heap 初始化，还可能影响其他模块运行。</p>
|
||
<p class="- topic/p p" data-ofbid="d354393e335__20250121172132"><strong class="+ topic/ph hi-d/b ph b">显示模块</strong></p>
|
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<p class="- topic/p p" data-ofbid="d354393e339__20250121172132">以 fb0 为 32 位 argb8888 格式，外接分辨率为 1024x600 的 LCD 为例：</p>
|
||
<p class="- topic/p p" data-ofbid="d354393e342__20250121172132">单 buffer 场景下需要 1024 * 600 * (32 / 8) = 2457600 byte, 约 <code class="+ topic/ph pr-d/codeph ph codeph">2.4M</code> CMA
|
||
内存</p>
|
||
<p class="- topic/p p" data-ofbid="d354393e348__20250121172132">双 buffer 场景下则需要 <code class="+ topic/ph pr-d/codeph ph codeph">4.8M</code></p>
|
||
<p class="- topic/p p" data-ofbid="d354393e353__20250121172132"><strong class="+ topic/ph hi-d/b ph b">音频模块</strong></p>
|
||
<p class="- topic/p p" data-ofbid="d354393e358__20250121172132">启用 ALSL 的场景下需要为音频模块预留 <code class="+ topic/ph pr-d/codeph ph codeph">1.5M</code> CMA 内存</p>
|
||
<p class="- topic/p p" data-ofbid="d354393e364__20250121172132">在 ALSL 加 I2S 的场景下则需要 <code class="+ topic/ph pr-d/codeph ph codeph">2.5M</code> CMA 内存</p>
|
||
<p class="- topic/p p" data-ofbid="d354393e370__20250121172132"><strong class="+ topic/ph hi-d/b ph b">通讯模块</strong></p>
|
||
<p class="- topic/p p" data-ofbid="d354393e374__20250121172132">WIFI, Bluetooth, USB 等通讯模块也会占用部分 CMA 内存，这个要根据实际场景进行推算。</p>
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<div class="- topic/note note tip note_tip" id="mpp_heap_interface_intro__note_rwl_mzh_d1c" data-ofbid="mpp_heap_interface_intro__note_rwl_mzh_d1c"><span class="note__title">提示：</span>
|
||
<p class="- topic/p p" data-ofbid="d354393e379__20250121172132">CMA 预留内存的大小 ≥ mpp heap + 其他模块，同时 CMA 预留内存大小遵循 <code class="+ topic/ph pr-d/codeph ph codeph">4M</code> 对齐。
|
||
为确保系统正常运行，在设置 CMA 预留内存时要保有一定的余量。</p>
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<div class=" wh_topic_toc "><div class="wh_topic_label">在本页上</div><ul><li class="section-item"><div class="section-title"><a href="#mpp_heap_interface_intro__section_l31_nwh_d1c" data-tocid="mpp_heap_interface_intro__section_l31_nwh_d1c">mpp heap 特点</a></div></li><li class="section-item"><div class="section-title"><a href="#mpp_heap_interface_intro__section_n31_nwh_d1c" data-tocid="mpp_heap_interface_intro__section_n31_nwh_d1c">mpp heap init</a></div></li><li class="section-item"><div class="section-title"><a href="#mpp_heap_interface_intro__section_p31_nwh_d1c" data-tocid="mpp_heap_interface_intro__section_p31_nwh_d1c">mpp heap export</a></div></li><li class="section-item"><div class="section-title"><a href="#mpp_heap_interface_intro__section_r31_nwh_d1c" data-tocid="mpp_heap_interface_intro__section_r31_nwh_d1c">mpp heap close</a></div></li><li class="section-item"><div class="section-title"><a href="#mpp_heap_interface_intro__section_t31_nwh_d1c" data-tocid="mpp_heap_interface_intro__section_t31_nwh_d1c">mpp heap destroy</a></div></li><li class="section-item"><div class="section-title"><a href="#mpp_heap_interface_intro__section_v31_nwh_d1c" data-tocid="mpp_heap_interface_intro__section_v31_nwh_d1c">mpp heap 接口</a></div></li><li class="section-item"><div class="section-title"><a href="#mpp_heap_interface_intro__section_bj1_nwh_d1c" data-tocid="mpp_heap_interface_intro__section_bj1_nwh_d1c">mpp heap 设置</a></div></li></ul></div>
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